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Verbal declarative memory impairments in specific language impairment are related to working memory deficits

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Lum, Jarrad A.G.; Ullman, Michael T.; Conti-Ramsden, Gina

2015-01-01

This study examined verbal declarative memory functioning in SLI and its relationship to working memory. Encoding, recall, and recognition of verbal information was examined in children with SLI who had below average working memory (SLILow WM), children with SLI who had average working memory (SLIAvg. WM) and, a group of non-language impaired children with average working memory (TDAvg. WM). The SLILow WM group was significantly worse than both the SLIAvg. WM and TDAvg. WM groups at encoding ...
Working Memory and Developmental Language Impairments

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Henry, Lucy A.; Botting, Nicola

2017-01-01

Children with developmental language impairments (DLI) are often reported to show difficulties with working memory. This review describes the four components of the well-established working memory model, and considers whether there is convincing evidence for difficulties within each component in children with DLI. The emphasis is on the most…
Short-term and working memory impairments in aphasia.

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Potagas, Constantin; Kasselimis, Dimitrios; Evdokimidis, Ioannis

2011-08-01

The aim of the present study is to investigate short-term memory and working memory deficits in aphasics in relation to the severity of their language impairment. Fifty-eight aphasic patients participated in this study. Based on language assessment, an aphasia score was calculated for each patient. Memory was assessed in two modalities, verbal and spatial. Mean scores for all memory tasks were lower than normal. Aphasia score was significantly correlated with performance on all memory tasks. Correlation coefficients for short-term memory and working memory were approximately of the same magnitude. According to our findings, severity of aphasia is related with both verbal and spatial memory deficits. Moreover, while aphasia score correlated with lower scores in both short-term memory and working memory tasks, the lack of substantial difference between corresponding correlation coefficients suggests a possible primary deficit in information retention rather than impairment in working memory. Copyright © 2011 Elsevier Ltd. All rights reserved.
Working, declarative and procedural memory in specific language impairment

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Lum, Jarrad A.G.; Conti-Ramsden, Gina; Page, Debra; Ullman, Michael T.

2012-01-01

According to the Procedural Deficit Hypothesis (PDH), abnormalities of brain structures underlying procedural memory largely explain the language deficits in children with specific language impairment (SLI). These abnormalities are posited to result in core deficits of procedural memory, which in turn explain the grammar problems in the disorder. The abnormalities are also likely to lead to problems with other, non-procedural functions, such as working memory, that rely at least partly on the affected brain structures. In contrast, declarative memory is expected to remain largely intact, and should play an important compensatory role for grammar. These claims were tested by examining measures of working, declarative and procedural memory in 51 children with SLI and 51 matched typically-developing (TD) children (mean age 10). Working memory was assessed with the Working Memory Test Battery for Children, declarative memory with the Children’s Memory Scale, and procedural memory with a visuo-spatial Serial Reaction Time task. As compared to the TD children, the children with SLI were impaired at procedural memory, even when holding working memory constant. In contrast, they were spared at declarative memory for visual information, and at declarative memory in the verbal domain after controlling for working memory and language. Visuo-spatial short-term memory was intact, whereas verbal working memory was impaired, even when language deficits were held constant. Correlation analyses showed neither visuo-spatial nor verbal working memory was associated with either lexical or grammatical abilities in either the SLI or TD children. Declarative memory correlated with lexical abilities in both groups of children. Finally, grammatical abilities were associated with procedural memory in the TD children, but with declarative memory in the children with SLI. These findings replicate and extend previous studies of working, declarative and procedural memory in SLI. Overall, we
Working memory and novel word learning in children with hearing impairment and children with specific language impairment.

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Hansson, K; Forsberg, J; Löfqvist, A; Mäki-Torkko, E; Sahlén, B

2004-01-01

Working memory is considered to influence a range of linguistic skills, i.e. vocabulary acquisition, sentence comprehension and reading. Several studies have pointed to limitations of working memory in children with specific language impairment. Few studies, however, have explored the role of working memory for language deficits in children with hearing impairment. The first aim was to compare children with mild-to-moderate bilateral sensorineural hearing impairment, children with a preschool diagnosis of specific language impairment and children with normal language development, aged 9-12 years, for language and working memory. The special focus was on the role of working memory in learning new words for primary school age children. The assessment of working memory included tests of phonological short-term memory and complex working memory. Novel word learning was assessed according to the methods of. In addition, a range of language tests was used to assess language comprehension, output phonology and reading. Children with hearing impairment performed significantly better than children with a preschool diagnosis of specific language impairment on tasks assessing novel word learning, complex working memory, sentence comprehension and reading accuracy. No significant correlation was found between phonological short-term memory and novel word learning in any group. The best predictor of novel word learning in children with specific language impairment and in children with hearing impairment was complex working memory. Furthermore, there was a close relationship between complex working memory and language in children with a preschool diagnosis of specific language impairment but not in children with hearing impairment. Complex working memory seems to play a significant role in vocabulary acquisition in primary school age children. The interpretation is that the results support theories suggesting a weakened influence of phonological short-term memory on novel word
Working memory limitations in children with severe language impairment.

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van Daal, John; Verhoeven, Ludo; van Leeuwe, Jan; van Balkom, Hans

2008-01-01

In the present study, the relations of various aspects of working memory to various aspects of language problems in a clinical sample of 97 Dutch speaking 5-year-old children with severe language problems were studied. The working memory and language abilities of the children were examined using an extensive battery of tests. Working memory was operationalized according to the model of Baddeley. Confirmative factor analyses revealed three memory factors: phonological, visual and central executive. Language was construed as a multifactorial construct, and confirmative factor analyses revealed four factors: lexical-semantic abilities, phonological abilities, syntactic abilities and speech production abilities. Moderate to high correlations were found between the memory and language factors. Structural equation modelling was used to further explore the relations between the different factors. Phonological memory was found to predict phonological abilities; central-executive memory predicted lexical-semantic abilities; and visual memory predicted speech production abilities. Phonological abilities also predicted syntactic abilities. Both the theoretical and clinical implications of the findings are discussed. The reader will be introduced to the concepts of multifactorial components of working memory as well as language impairment. Secondly the reader will recognize that working memory and language impairment factors can be related. Particular emphasis will be placed on phonological memory, central-executive memory and visual memory and their possible prediction of specific components of language impairment.
Working, declarative and procedural memory in specific language impairment

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Lum, J. A. G.; Conti-Ramsden, G.; Page, D.

2012-01-01

at declarative memory for visual information, and at declarative memory in the verbal domain after controlling for working memory and language. Visuo-spatial short-term memory was intact, whereas verbal working memory was impaired, even when language deficits were held constant. Correlation analyses showed......According to the Procedural Deficit Hypothesis (PDH), abnormalities of brain structures underlying procedural memory largely explain the language deficits in children with specific language impairment (SLI). These abnormalities are posited to result in core deficits of procedural memory, which...... in turn explain the grammar problems in the disorder. The abnormalities are also likely to lead to problems with other, non-procedural functions, such as working memory, that rely at least partly on the affected brain structures. In contrast, declarative memory is expected to remain largely intact...
Structural correlates of impaired working memory in hippocampal sclerosis

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Winston, Gavin P; Stretton, Jason; Sidhu, Meneka K; Symms, Mark R; Thompson, Pamela J; Duncan, John S

2013-01-01

Purpose: Temporal lobe epilepsy (TLE) has been considered to impair long-term memory, whilst not affecting working memory, but recent evidence suggests that working memory is compromised. Functional MRI (fMRI) studies demonstrate that working memory involves a bilateral frontoparietal network the activation of which is disrupted in hippocampal sclerosis (HS). A specific role of the hippocampus to deactivate during working memory has been proposed with this mechanism faulty in patients with HS. Structural correlates of disrupted working memory in HS have not been explored. Methods: We studied 54 individuals with medically refractory TLE and unilateral HS (29 left) and 28 healthy controls. Subjects underwent 3T structural MRI, a visuospatial n-back fMRI paradigm and diffusion tensor imaging (DTI). Working memory capacity assessed by three span tasks (digit span backwards, gesture span, motor sequences) was combined with performance in the visuospatial paradigm to give a global working memory measure. Gray and white matter changes were investigated using voxel-based morphometry and voxel-based analysis of DTI, respectively. Key Findings: Individuals with left or right HS performed less well than healthy controls on all measures of working memory. fMRI demonstrated a bilateral frontoparietal network during the working memory task with reduced activation of the right parietal lobe in both patient groups. In left HS, gray matter loss was seen in the ipsilateral hippocampus and parietal lobe, with maintenance of the gray matter volume of the contralateral parietal lobe associated with better performance. White matter integrity within the frontoparietal network, in particular the superior longitudinal fasciculus and cingulum, and the contralateral temporal lobe, was associated with working memory performance. In right HS, gray matter loss was also seen in the ipsilateral hippocampus and parietal lobe. Working memory performance correlated with the gray matter volume of
Working memory and reward association learning impairments in obesity.

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Coppin, Géraldine; Nolan-Poupart, Sarah; Jones-Gotman, Marilyn; Small, Dana M

2014-12-01

Obesity has been associated with impaired executive functions including working memory. Less explored is the influence of obesity on learning and memory. In the current study we assessed stimulus reward association learning, explicit learning and memory and working memory in healthy weight, overweight and obese individuals. Explicit learning and memory did not differ as a function of group. In contrast, working memory was significantly and similarly impaired in both overweight and obese individuals compared to the healthy weight group. In the first reward association learning task the obese, but not healthy weight or overweight participants consistently formed paradoxical preferences for a pattern associated with a negative outcome (fewer food rewards). To determine if the deficit was specific to food reward a second experiment was conducted using money. Consistent with Experiment 1, obese individuals selected the pattern associated with a negative outcome (fewer monetary rewards) more frequently than healthy weight individuals and thus failed to develop a significant preference for the most rewarded patterns as was observed in the healthy weight group. Finally, on a probabilistic learning task, obese compared to healthy weight individuals showed deficits in negative, but not positive outcome learning. Taken together, our results demonstrate deficits in working memory and stimulus reward learning in obesity and suggest that obese individuals are impaired in learning to avoid negative outcomes. Copyright © 2014 Elsevier Ltd. All rights reserved.
Rethinking the Connection between Working Memory and Language Impairment

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Archibald, Lisa M. D.; Harder Griebeling, Katherine

2016-01-01

Background: Working memory deficits have been found for children with specific language impairment (SLI) on tasks imposing increasing short-term memory load with or without additional, consistent (and simple) processing load. Aims: To examine the processing function of working memory in children with low language (LL) by employing tasks imposing…
Phonological working memory and auditory processing speed in children with specific language impairment

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Fatemeh Haresabadi

2015-02-01

Full Text Available Background and Aim: Specific language impairment (SLI, one variety of developmental language disorder, has attracted much interest in recent decades. Much research has been conducted to discover why some children have a specific language impairment. So far, research has failed to identify a reason for this linguistic deficiency. Some researchers believe language disorder causes defects in phonological working memory and affects auditory processing speed. Therefore, this study reviews the results of research investigating these two factors in children with specific language impairment.Recent Findings: Studies have shown that children with specific language impairment face constraints in phonological working memory capacity. Memory deficit is one possible cause of linguistic disorder in children with specific language impairment. However, in these children, disorder in information processing speed is observed, especially regarding the auditory aspect.Conclusion: Much more research is required to adequately explain the relationship between phonological working memory and auditory processing speed with language. However, given the role of phonological working memory and auditory processing speed in language acquisition, a focus should be placed on phonological working memory capacity and auditory processing speed in the assessment and treatment of children with a specific language impairment.
Impaired contingent attentional capture predicts reduced working memory capacity in schizophrenia.

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Jutta S Mayer

Full Text Available Although impairments in working memory (WM are well documented in schizophrenia, the specific factors that cause these deficits are poorly understood. In this study, we hypothesized that a heightened susceptibility to attentional capture at an early stage of visual processing would result in working memory encoding problems. 30 patients with schizophrenia and 28 demographically matched healthy participants were presented with a search array and asked to report the orientation of the target stimulus. In some of the trials, a flanker stimulus preceded the search array that either matched the color of the target (relevant-flanker capture or appeared in a different color (irrelevant-flanker capture. Working memory capacity was determined in each individual using the visual change detection paradigm. Patients needed considerably more time to find the target in the no-flanker condition. After adjusting the individual exposure time, both groups showed equivalent capture costs in the irrelevant-flanker condition. However, in the relevant-flanker condition, capture costs were increased in patients compared to controls when the stimulus onset asynchrony between the flanker and the search array was high. Moreover, the increase in relevant capture costs correlated negatively with working memory capacity. This study demonstrates preserved stimulus-driven attentional capture but impaired contingent attentional capture associated with low working memory capacity in schizophrenia. These findings suggest a selective impairment of top-down attentional control in schizophrenia, which may impair working memory encoding.
Impaired contingent attentional capture predicts reduced working memory capacity in schizophrenia.

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Mayer, Jutta S; Fukuda, Keisuke; Vogel, Edward K; Park, Sohee

2012-01-01

Although impairments in working memory (WM) are well documented in schizophrenia, the specific factors that cause these deficits are poorly understood. In this study, we hypothesized that a heightened susceptibility to attentional capture at an early stage of visual processing would result in working memory encoding problems. 30 patients with schizophrenia and 28 demographically matched healthy participants were presented with a search array and asked to report the orientation of the target stimulus. In some of the trials, a flanker stimulus preceded the search array that either matched the color of the target (relevant-flanker capture) or appeared in a different color (irrelevant-flanker capture). Working memory capacity was determined in each individual using the visual change detection paradigm. Patients needed considerably more time to find the target in the no-flanker condition. After adjusting the individual exposure time, both groups showed equivalent capture costs in the irrelevant-flanker condition. However, in the relevant-flanker condition, capture costs were increased in patients compared to controls when the stimulus onset asynchrony between the flanker and the search array was high. Moreover, the increase in relevant capture costs correlated negatively with working memory capacity. This study demonstrates preserved stimulus-driven attentional capture but impaired contingent attentional capture associated with low working memory capacity in schizophrenia. These findings suggest a selective impairment of top-down attentional control in schizophrenia, which may impair working memory encoding.
Dissociation of working memory impairments and attention-deficit/hyperactivity disorder in the brain.

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Mattfeld, Aaron T; Whitfield-Gabrieli, Susan; Biederman, Joseph; Spencer, Thomas; Brown, Ariel; Fried, Ronna; Gabrieli, John D E

2016-01-01

Prevailing neuropsychological models of attention-deficit/hyperactivity disorder (ADHD) propose that ADHD arises from deficits in executive functions such as working memory, but accumulating clinical evidence suggests a dissociation between ADHD and executive dysfunctions. This study examined whether ADHD and working memory capacity are behaviorally and neurobiologically separable using functional magnetic resonance imaging (fMRI). Participants diagnosed with ADHD in childhood who subsequently remitted or persisted in their diagnosis as adults were characterized at follow-up in adulthood as either impaired or unimpaired in spatial working memory relative to controls who never had ADHD. ADHD participants with impaired spatial working memory performed worse than controls and ADHD participants with unimpaired working memory during an n-back working memory task while being scanned. Both controls and ADHD participants with unimpaired working memory exhibited significant linearly increasing activation in the inferior frontal junction, precuneus, lingual gyrus, and cerebellum as a function of working-memory load, and these activations did not differ significantly between these groups. ADHD participants with impaired working memory exhibited significant hypoactivation in the same regions, which was significantly different than both control participants and ADHD participants with unimpaired working memory. These findings support both a behavioral and neurobiological dissociation between ADHD and working memory capacity.
Dissociation of working memory impairments and attention-deficit/hyperactivity disorder in the brain

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Aaron T. Mattfeld

2016-01-01

Full Text Available Prevailing neuropsychological models of attention-deficit/hyperactivity disorder (ADHD propose that ADHD arises from deficits in executive functions such as working memory, but accumulating clinical evidence suggests a dissociation between ADHD and executive dysfunctions. This study examined whether ADHD and working memory capacity are behaviorally and neurobiologically separable using functional magnetic resonance imaging (fMRI. Participants diagnosed with ADHD in childhood who subsequently remitted or persisted in their diagnosis as adults were characterized at follow-up in adulthood as either impaired or unimpaired in spatial working memory relative to controls who never had ADHD. ADHD participants with impaired spatial working memory performed worse than controls and ADHD participants with unimpaired working memory during an n-back working memory task while being scanned. Both controls and ADHD participants with unimpaired working memory exhibited significant linearly increasing activation in the inferior frontal junction, precuneus, lingual gyrus, and cerebellum as a function of working-memory load, and these activations did not differ significantly between these groups. ADHD participants with impaired working memory exhibited significant hypoactivation in the same regions, which was significantly different than both control participants and ADHD participants with unimpaired working memory. These findings support both a behavioral and neurobiological dissociation between ADHD and working memory capacity.
Dissociation of working memory impairments and attention-deficit/hyperactivity disorder in the brain

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Mattfeld, Aaron T.; Whitfield-Gabrieli, Susan; Biederman, Joseph; Spencer, Thomas; Brown, Ariel; Fried, Ronna; Gabrieli, John D.E.

2015-01-01

Prevailing neuropsychological models of attention-deficit/hyperactivity disorder (ADHD) propose that ADHD arises from deficits in executive functions such as working memory, but accumulating clinical evidence suggests a dissociation between ADHD and executive dysfunctions. This study examined whether ADHD and working memory capacity are behaviorally and neurobiologically separable using functional magnetic resonance imaging (fMRI). Participants diagnosed with ADHD in childhood who subsequently remitted or persisted in their diagnosis as adults were characterized at follow-up in adulthood as either impaired or unimpaired in spatial working memory relative to controls who never had ADHD. ADHD participants with impaired spatial working memory performed worse than controls and ADHD participants with unimpaired working memory during an n-back working memory task while being scanned. Both controls and ADHD participants with unimpaired working memory exhibited significant linearly increasing activation in the inferior frontal junction, precuneus, lingual gyrus, and cerebellum as a function of working-memory load, and these activations did not differ significantly between these groups. ADHD participants with impaired working memory exhibited significant hypoactivation in the same regions, which was significantly different than both control participants and ADHD participants with unimpaired working memory. These findings support both a behavioral and neurobiological dissociation between ADHD and working memory capacity. PMID:26900567
Impairments of spatial working memory and attention following acute psychosocial stress.

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Olver, James S; Pinney, Myra; Maruff, Paul; Norman, Trevor R

2015-04-01

Few studies have investigated the effect of an acute psychosocial stress paradigm on impaired attention and working memory in humans. Further, the duration of any stress-related cognitive impairment remains unclear. The aim of this study was to examine the effect of an acute psychosocial stress paradigm, the Trier Social Stress, on cognitive function in healthy volunteers. Twenty-three healthy male and female subjects were exposed to an acute psychosocial stress task. Physiological measures (salivary cortisol, heart rate and blood pressure) and subjective stress ratings were measured at baseline, in anticipation of stress, immediately post-stress and after a period of rest. A neuropsychological test battery including spatial working memory and verbal memory was administered at each time point. Acute psychosocial stress produced significant increases in cardiovascular and subjective measures in the anticipatory and post-stress period, which recovered to baseline after rest. Salivary cortisol steadily declined over the testing period. Acute psychosocial stress impaired delayed verbal recall, attention and spatial working memory. Attention remained impaired, and delayed verbal recall continued to decline after rest. Acute psychosocial stress is associated with an impairment of a broad range of cognitive functions in humans and with prolonged abnormalities in attention and memory. Copyright © 2014 John Wiley & Sons, Ltd.
[GLIATILIN CORRECTION OF WORKING AND REFERENCE SPATIAL MEMORY IMPAIRMENT IN AGED RATS].

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Tyurenkov, I N; Volotova, E V; Kurkin, D V

2015-01-01

This work was aimed at evaluating the influence of gliatilin administration on the spatial memory in aged rats. Cognitive function and spatial memory in animals was evaluated using radial (8-beam) maze test. Errors of working spatial memory and reference memory were used as indicators of impaired cognitive function. It was found that aged (24-month) rats compared with younger (6-months) age group exhibited cognitive impairment, as manifested by deterioration of short- and long-term memory processes. Course administration of gliatilin in rats of the older age group at a dose of 100 mg/kg resulted in significant improvement of the working and reference spatial memory in aged rats.
WORKING MEMORY IMPAIRMENT AS AN ENDOPHENOTYPIC MARKER OF A SCHIZOPHRENIA DIATHESIS.

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Park, Sohee; Gooding, Diane C

2014-09-01

This chapter focuses on the viability of working memory impairment as an endophenotypic marker of a schizophrenia diathesis. It begins with an introduction of the construct of working memory. It follows with a review of the operational criteria for defining an endophenotype. Research findings regarding the working memory performance of schizophrenia and schizophrenia-spectrum patients, first-degree relatives of schizophrenia patients and healthy controls, are reviewed in terms of the criteria for being considered an endophenotypic marker. Special attention is paid to specific components of the working memory deficit (namely, encoding, maintenance, and manipulation), in terms of which aspects are likely to be the best candidates for endophenotypes. We consider the extant literature regarding working memory performance in bipolar disorder and major depression in order to address the issue of relative specificity to schizophrenia. Despite some unresolved issues, it appears that working memory impairment is a very promising candidate for an endophenotypic marker of a schizophrenia diathesis but not for mood disorders. Throughout this chapter, we identify future directions for research in this exciting and dynamic area of research and evaluate the contribution of working memory research to our understanding of schizophrenia.
Working memory impairment as an endophenotypic marker of a schizophrenia diathesis

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Sohee Park

2014-09-01

Full Text Available This review focuses on the viability of working memory impairment as an endophenotypic marker of a schizophrenia diathesis. It begins with an introduction of the construct of working memory. It follows with a consideration of the operational criteria for defining an endophenotype. Research findings regarding the working memory performance of schizophrenia and schizophrenia-spectrum patients, first-degree relatives of schizophrenia patients and healthy controls, are reviewed in terms of the criteria for being considered an endophenotypic marker. Special attention is paid to specific components of the working memory deficit (namely, encoding, maintenance, and manipulation, in terms of which aspects are likely to be the best candidates for endophenotypes. We examine the extant literature regarding working memory performance in bipolar disorder and major depression in order to address the issue of relative specificity to schizophrenia. Despite some unresolved issues, it appears that working memory impairment is a very promising candidate for an endophenotypic marker of a schizophrenia diathesis but not for mood disorders. Throughout this review, we identify future directions for research in this exciting and dynamic area of research and evaluate the contribution of working memory research to our understanding of schizophrenia.

Glucocorticoids in the prefrontal cortex enhance memory consolidation and impair working memory by a common neural mechanism

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Barsegyan, Areg; Mackenzie, Scott M.; Kurose, Brian D.; McGaugh, James L.; Roozendaal, Benno

2010-01-01

It is well established that acute administration of adrenocortical hormones enhances the consolidation of memories of emotional experiences and, concurrently, impairs working memory. These different glucocorticoid effects on these two memory functions have generally been considered to be independently regulated processes. Here we report that a glucocorticoid receptor agonist administered into the medial prefrontal cortex (mPFC) of male Sprague-Dawley rats both enhances memory consolidation and impairs working memory. Both memory effects are mediated by activation of a membrane-bound steroid receptor and depend on noradrenergic activity within the mPFC to increase levels of cAMP-dependent protein kinase. These findings provide direct evidence that glucocorticoid effects on both memory consolidation and working memory share a common neural influence within the mPFC. PMID:20810923
Working Memory Functioning in Children with Learning Disorders and Specific Language Impairment

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Schuchardt, Kirsten; Bockmann, Ann-Katrin; Bornemann, Galina; Maehler, Claudia

2013-01-01

Purpose: On the basis of Baddeley's working memory model (1986), we examined working memory functioning in children with learning disorders with and without specific language impairment (SLI). We pursued the question whether children with learning disorders exhibit similar working memory deficits as children with additional SLI. Method: In…
Brain injury impairs working memory and prefrontal circuit function

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Colin James Smith

2015-11-01

Full Text Available More than 2.5 million Americans suffer a traumatic brain injury (TBI each year. Even mild to moderate traumatic brain injury causes long-lasting neurological effects. Despite its prevalence, no therapy currently exists to treat the underlying cause of cognitive impairment suffered by TBI patients. Following lateral fluid percussion injury (LFPI, the most widely used experimental model of TBI, we investigated alterations in working memory and excitatory/inhibitory synaptic balance in the prefrontal cortex. LFPI impaired working memory as assessed with a T-maze behavioral task. Field excitatory postsynaptic potentials recorded in the prefrontal cortex were reduced in slices derived from brain-injured mice. Spontaneous and miniature excitatory postsynaptic currents onto layer 2/3 neurons were more frequent in slices derived from LFPI mice while inhibitory currents onto layer 2/3 neurons were smaller after LFPI. Additionally, an increase in action potential threshold and concomitant decrease in firing rate was observed in layer 2/3 neurons in slices from injured animals. Conversely, no differences in excitatory or inhibitory synaptic transmission onto layer 5 neurons were observed; however, layer 5 neurons demonstrated a decrease in input resistance and action potential duration after LFPI. These results demonstrate synaptic and intrinsic alterations in prefrontal circuitry that may underlie working memory impairment caused by TBI.
Comparison of reading comprehension and working memory in hearing-impaired and normal-hearing children

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Mohammad Rezaei

2013-03-01

Full Text Available Background and Aim: Reading is the most important human need for learning. In normal-hearing people working memory is a predictor of reading comprehension. In this study the relationship between working memory and reading comprehension skills was studied in hearing-impaired children, and then compared with the normal-hearing group.Methods: This was a descriptive-analytic study. The working memory and reading comprehension skills of 18 (8 male, 10 female sever hearing-impaired children in year five of exceptional schools were compared by means of a reading test with 18 hearing children as control group. The subjects in the control group were of the same gender and educational level of the sample group.Results: The children with hearing loss performed similarly to the normal-hearing children in tasks related to auditory-verbal memory of sounds (reverse, visual-verbal memory of letters, and visual-verbal memory of pictures. However, they showed lower levels of performance in reading comprehension (p<0.001. Moreover, no significant relationship was observed between working memory and reading comprehension skills.Conclusion: Findings indicated that children with hearing loss have a significant impairment in the reading comprehension skill. Impairment in language knowledge and vocabulary may be the main cause of poor reading comprehension in these children. In hearing-impaired children working memory is not a strong predictor of reading comprehension.
Impulsivity, Working Memory, and Impaired Control over Alcohol: A Latent Variable Analysis

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Wardell, Jeffrey D.; Quilty, Lena C.; Hendershot, Christian S.

2017-01-01

Impaired control over alcohol is an important risk factor for heavy drinking among young adults and may mediate, in part, the association between personality risk and alcohol problems. Research suggests that trait impulsivity is associated with impaired control over alcohol; however, few studies of this association have included a range of impulsivity facets. The purpose of this study was to examine specific pathways from higher-order impulsivity factors to alcohol problems mediated via impaired control over alcohol. We also examined the moderating role of working memory in these associations. Young heavy drinkers (N=300) completed two multidimensional impulsivity measures (UPPS-P and BIS-11) along with self-report measures of impaired control over alcohol, alcohol use, and alcohol problems. Working memory was assessed using a computerized digit span task. Results showed that the impulsivity facets loaded onto two higher-order factors that were labeled response and reflection impulsivity. Response impulsivity predicted unique variance in self-reported impaired control and alcohol problems, whereas reflection impulsivity predicted unique variance in heavy drinking frequency only. Further, significant indirect associations were observed from response and reflection impulsivity to alcohol problems mediated via impaired control and heavy drinking frequency, respectively. Working memory and sensation seeking were not uniquely associated with the alcohol variables, and no support was found for the moderating role of working memory. The results help to clarify associations among impulsivity, impaired control, and alcohol problems, suggesting that impaired control may play a specific role in the pathway to alcohol problems from response impulsivity but not from reflection impulsivity. PMID:27269291
Working, declarative and procedural memory in specific language impairment

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Lum, Jarrad A.G.; Conti-Ramsden, Gina; Page, Debra; Ullman, Michael T.

2012-01-01

According to the Procedural Deficit Hypothesis (PDH), abnormalities of brain structures underlying procedural memory largely explain the language deficits in children with specific language impairment (SLI). These abnormalities are posited to result in core deficits of procedural memory, which in turn explain the grammar problems in the disorder. The abnormalities are also likely to lead to problems with other, non-procedural functions, such as working memory, that rely at least partly on the...
Impaired theta-gamma coupling during working memory performance in schizophrenia.

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Barr, Mera S; Rajji, Tarek K; Zomorrodi, Reza; Radhu, Natasha; George, Tony P; Blumberger, Daniel M; Daskalakis, Zafiris J

2017-11-01

Working memory deficits represent a core feature of schizophrenia. These deficits have been associated with dysfunctional dorsolateral prefrontal cortex (DLPFC) cortical oscillations. Theta-gamma coupling describes the modulation of gamma oscillations by theta phasic activity that has been directly associated with the ordering of information during working memory performance. Evaluating theta-gamma coupling may provide greater insight into the neural mechanisms mediating working memory deficits in this disorder. Thirty-eight patients diagnosed with schizophrenia or schizoaffective disorder and 38 healthy controls performed the verbal N-Back task administered at 4 levels, while EEG was recorded. Theta (4-7Hz)-gamma (30-50Hz) coupling was calculated for target and non-target correct trials for each working memory load. The relationship between theta-gamma coupling and accuracy was determined. Theta-gamma coupling was significantly and selectively impaired during correct responses to target letters among schizophrenia patients compared to healthy controls. A significant and positive relationship was found between theta-gamma coupling and 3-Back accuracy in controls, while this relationship was not observed in patients. These findings suggest that impaired theta-gamma coupling contribute to working memory dysfunction in schizophrenia. Future work is needed to evaluate the predictive utility of theta-gamma coupling as a neurophysiological marker for functional outcomes in this disorder. Copyright © 2017. Published by Elsevier B.V.
Verbal working memory and reading abilities among students with visual impairment.

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Argyropoulos, Vassilios; Masoura, Elvira; Tsiakali, Thomai K; Nikolaraizi, Magda; Lappa, Christina

2017-05-01

This study investigated the relationship between working memory (WM) and reading abilities among students with visual impairment (VI). Seventy-five students with VI (visually impairment and blindness), aged 10-15 years old participated in the study, of whom 44 were visually impaired and 31 were blind. The participants' reading ability was assessed with the standardized reading ability battery Test-A (Padeliadu & Antoniou, 2008) and their verbal working memory ability was assessed with the listening recall task from the Working Memory Test Battery for Children (Pickering et al., 2001). Data analysis indicated a strong correlation between verbal WM and decoding, reading comprehension and overall reading ability among the participants with VI, while no correlation was found between reading fluency and verbal WM. The present study points out the important role of verbal WM in reading among students who are VI and carries implications for the education of those individuals. Copyright © 2017 Elsevier Ltd. All rights reserved.
Abnormal neural activation patterns underlying working memory impairment in chronic phencyclidine-treated mice.

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Yosefu Arime

Full Text Available Working memory impairment is a hallmark feature of schizophrenia and is thought be caused by dysfunctions in the prefrontal cortex (PFC and associated brain regions. However, the neural circuit anomalies underlying this impairment are poorly understood. The aim of this study is to assess working memory performance in the chronic phencyclidine (PCP mouse model of schizophrenia, and to identify the neural substrates of working memory. To address this issue, we conducted the following experiments for mice after withdrawal from chronic administration (14 days of either saline or PCP (10 mg/kg: (1 a discrete paired-trial variable-delay task in T-maze to assess working memory, and (2 brain-wide c-Fos mapping to identify activated brain regions relevant to this task performance either 90 min or 0 min after the completion of the task, with each time point examined under working memory effort and basal conditions. Correct responses in the test phase of the task were significantly reduced across delays (5, 15, and 30 s in chronic PCP-treated mice compared with chronic saline-treated controls, suggesting delay-independent impairments in working memory in the PCP group. In layer 2-3 of the prelimbic cortex, the number of working memory effort-elicited c-Fos+ cells was significantly higher in the chronic PCP group than in the chronic saline group. The main effect of working memory effort relative to basal conditions was to induce significantly increased c-Fos+ cells in the other layers of prelimbic cortex and the anterior cingulate and infralimbic cortex regardless of the different chronic regimens. Conversely, this working memory effort had a negative effect (fewer c-Fos+ cells in the ventral hippocampus. These results shed light on some putative neural networks relevant to working memory impairments in mice chronically treated with PCP, and emphasize the importance of the layer 2-3 of the prelimbic cortex of the PFC.
Physical Performance Is Associated with Working Memory in Older People with Mild to Severe Cognitive Impairment

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K. M. Volkers

2014-01-01

Full Text Available Background. Physical performances and cognition are positively related in cognitively healthy people. The aim of this study was to examine whether physical performances are related to specific cognitive functioning in older people with mild to severe cognitive impairment. Methods. This cross-sectional study included 134 people with a mild to severe cognitive impairment (mean age 82 years. Multiple linear regression was performed, after controlling for covariates and the level of global cognition, with the performances on mobility, strength, aerobic fitness, and balance as predictors and working memory and episodic memory as dependent variables. Results. The full models explain 49–57% of the variance in working memory and 40–43% of episodic memory. Strength, aerobic fitness, and balance are significantly associated with working memory, explaining 3–7% of its variance, irrespective of the severity of the cognitive impairment. Physical performance is not related to episodic memory in older people with mild to severe cognitive impairment. Conclusions. Physical performance is associated with working memory in older people with cognitive impairment. Future studies should investigate whether physical exercise for increased physical performance can improve cognitive functioning. This trial is registered with ClinicalTrials.gov NTR1482.
Selective noradrenaline depletion impairs working memory and hippocampal neurogenesis.

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Coradazzi, Marino; Gulino, Rosario; Fieramosca, Francesco; Falzacappa, Lucia Verga; Riggi, Margherita; Leanza, Giampiero

2016-12-01

Noradrenergic neurons in the locus coeruleus play a role in learning and memory, and their loss is an early event in Alzheimer's disease pathogenesis. Moreover, noradrenaline may sustain hippocampal neurogenesis; however, whether are these events related is still unknown. Four to five weeks following the selective immunotoxic ablation of locus coeruleus neurons, young adult rats underwent reference and working memory tests, followed by postmortem quantitative morphological analyses to assess the extent of the lesion, as well as the effects on proliferation and/or survival of neural progenitors in the hippocampus. When tested in the Water Maze task, lesioned animals exhibited no reference memory deficit, whereas working memory abilities were seen significantly impaired, as compared with intact or sham-lesioned controls. Stereological analyses confirmed a dramatic noradrenergic neuron loss associated to reduced proliferation, but not survival or differentiation, of 5-bromo-2'deoxyuridine-positive progenitors in the dentate gyrus. Thus, ascending noradrenergic afferents may be involved in more complex aspects of cognitive performance (i.e., working memory) possibly via newly generated progenitors in the hippocampus. Copyright © 2016 Elsevier Inc. All rights reserved.
Distinguishing between impairments of working memory and inhibitory control in cases of early dementia.

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Crawford, Trevor J; Higham, Steve

2016-01-29

Dementia (most notably, Alzheimer's Disease) is often associated with impairments of both working memory and inhibitory control. However, it is unclear whether these are functionally distinct impairments. We addressed the issue of whether working memory and inhibitory control can be dissociated, using data from a sample of patients who were recruited in a longitudinal study (Crawford et al., 2013, 2015). The first case revealed a preserved working memory capacity together with poor inhibitory control in the anti-saccade task. A longitudinal follow-up revealed that the defective inhibitory control emerged 12-months before the dementia was evident on the mini-mental state examination assessment. A second case revealed a poor working memory together with a well-preserved level of inhibitory control. The dissociation of working memory and inhibitory control was confirmed statistically in 7 additional cases. These findings yield converging evidence that working memory and inhibitory control are distinct cognitive operations and challenges the Kimberg and Farah (2000) cognitive model of working memory. Copyright © 2015 Elsevier Ltd. All rights reserved.
Working Memory Capacity and Language Processes in Children with Specific Language Impairment

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Marton, Klara; Schwartz, Richard G.

2003-01-01

This study examined the interaction between working memory and language comprehension in children with specific language impairment (SLI), focusing on the function of the central executive component and its interaction with the phonological loop (A. D. Baddeley, 1986) in complex working memory tasks. Thirteen children with SLI and 13 age-matched…
Inactivation of Primate Prefrontal Cortex Impairs Auditory and Audiovisual Working Memory.

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Plakke, Bethany; Hwang, Jaewon; Romanski, Lizabeth M

2015-07-01

The prefrontal cortex is associated with cognitive functions that include planning, reasoning, decision-making, working memory, and communication. Neurophysiology and neuropsychology studies have established that dorsolateral prefrontal cortex is essential in spatial working memory while the ventral frontal lobe processes language and communication signals. Single-unit recordings in nonhuman primates has shown that ventral prefrontal (VLPFC) neurons integrate face and vocal information and are active during audiovisual working memory. However, whether VLPFC is essential in remembering face and voice information is unknown. We therefore trained nonhuman primates in an audiovisual working memory paradigm using naturalistic face-vocalization movies as memoranda. We inactivated VLPFC, with reversible cortical cooling, and examined performance when faces, vocalizations or both faces and vocalization had to be remembered. We found that VLPFC inactivation impaired subjects' performance in audiovisual and auditory-alone versions of the task. In contrast, VLPFC inactivation did not disrupt visual working memory. Our studies demonstrate the importance of VLPFC in auditory and audiovisual working memory for social stimuli but suggest a different role for VLPFC in unimodal visual processing. The ventral frontal lobe, or inferior frontal gyrus, plays an important role in audiovisual communication in the human brain. Studies with nonhuman primates have found that neurons within ventral prefrontal cortex (VLPFC) encode both faces and vocalizations and that VLPFC is active when animals need to remember these social stimuli. In the present study, we temporarily inactivated VLPFC by cooling the cortex while nonhuman primates performed a working memory task. This impaired the ability of subjects to remember a face and vocalization pair or just the vocalization alone. Our work highlights the importance of the primate VLPFC in the processing of faces and vocalizations in a manner that
Interference impacts working memory in mild cognitive impairment

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Sara Aurtenetxe

2016-10-01

Full Text Available Mild cognitive impairment (MCI is considered a transitional stage between healthy aging and dementia, specifically Alzheimer’s disease (AD. The most common cognitive impairment of MCI includes episodic memory loss and difficulties in working memory (WM. Interference can deplete WM, and an optimal WM performance requires an effective control of attentional resources between the memoranda and the incoming stimuli. Difficulties in handling interference lead to forgetting. However, the interplay between interference and WM in MCI is not well understood and needs further investigation. The current study investigated the effect of interference during a WM task in 20 MCIs and 20 healthy elder volunteers. Participants performed a delayed match-to-sample paradigm which consisted in two interference conditions, distraction and interruption, and one control condition without any interference. Results evidenced a disproportionate impact of interference on the WM performance of MCIs, mainly in the presence of interruption. These findings demonstrate that interference, and more precisely interruption, is an important proxy for memory-related deficits in MCI. Thus the current findings reveal novel evidence regarding the causes of WM forgetting in MCI patients, associated with difficulties in the mechanisms of attentional control.
Theta-Gamma Coupling and Working Memory in Alzheimer’s Dementia and Mild Cognitive Impairment

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Michelle S. Goodman

2018-04-01

Full Text Available Working memory deficits are common among individuals with Alzheimer’s dementia (AD or mild cognitive impairment (MCI. Yet, little is known about the mechanisms underlying these deficits. Theta-gamma coupling—the modulation of high-frequency gamma oscillations by low-frequency theta oscillations—is a neurophysiologic process underlying working memory. We assessed the relationship between theta-gamma coupling and working memory deficits in AD and MCI. We hypothesized that: (1 individuals with AD would display the most significant working memory impairments followed by MCI and finally healthy control (HC participants; and (2 there would be a significant association between working memory performance and theta-gamma coupling across all participants. Ninety-eight participants completed the N-back working memory task during an electroencephalography (EEG recording: 33 with AD (mean ± SD age: 76.5 ± 6.2, 34 with MCI (mean ± SD age: 74.8 ± 5.9 and 31 HCs (mean ± SD age: 73.5 ± 5.2. AD participants performed significantly worse than control and MCI participants on the 1- and 2-back conditions. Regarding theta-gamma coupling, AD participants demonstrated the lowest level of coupling followed by the MCI and finally control participants on the 2-back condition. Finally, a linear regression analysis demonstrated that theta-gamma coupling (β = 0.69, p < 0.001 was the most significant predictor of 2-back performance. Our results provide evidence for a relationship between altered theta-gamma coupling and working memory deficits in individuals with AD and MCI. They also provide insight into a potential mechanism underlying working memory impairments in these individuals.
Working Memory and Learning in Children with Developmental Coordination Disorder and Specific Language Impairment

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Alloway, Tracy Packiam; Archibald, Lisa

2008-01-01

The authors compared 6- to 11-year-olds with developmental coordination disorder (DCD) and those with specific language impairment (SLI) on measures of memory (verbal and visuospatial short-term and working memory) and learning (reading and mathematics). Children with DCD with typical language skills were impaired in all four areas of memory…
Electrophysiological Repetition Effects in Persons with Mild Cognitive Impairment depend upon Working Memory Demand.

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Broster, Lucas S; Jenkins, Shonna L; Holmes, Sarah D; Edwards, Matthew G; Jicha, Gregory A; Jiang, Yang

2018-05-07

Forms of implicit memory, including repetition effects, are preserved relative to explicit memory in clinical Alzheimer's disease. Consequently, cognitive interventions for persons with Alzheimer's disease have been developed that leverage this fact. However, despite the clinical robustness of behavioral repetition effects, altered neural mechanisms of repetition effects are studied as biomarkers of both clinical Alzheimer's disease and pre-morbid Alzheimer's changes in the brain. We hypothesized that the clinical preservation of behavioral repetition effects results in part from concurrent operation of discrete memory systems. We developed two experiments that included probes of emotional repetition effects differing in that one included an embedded working memory task. We found that neural repetition effects manifested in patients with amnestic mild cognitive impairment, the earliest form of clinical Alzheimer's disease, during emotional working memory tasks, but they did not manifest during the task that lacked the embedded working memory manipulation. Specifically, the working memory task evoked neural repetition effects in the P600 time-window, but the same neural mechanism was only minimally implicated in the task without a working memory component. We also found that group differences in behavioral repetition effects were smaller in the experiment with a working memory task. We suggest that cross-domain cognitive challenge can expose "defunct" neural capabilities of individuals with amnestic mild cognitive impairment. Copyright © 2018. Published by Elsevier Ltd.
Complex Sentence Comprehension and Working Memory in Children with Specific Language Impairment

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Montgomery, James W.; Evans, Julia L.

2009-01-01

Purpose: This study investigated the association of 2 mechanisms of working memory (phonological short-term memory [PSTM], attentional resource capacity/allocation) with the sentence comprehension of school-age children with specific language impairment (SLI) and 2 groups of control children. Method: Twenty-four children with SLI, 18 age-matched…
Does emotional memory enhancement assist the memory-impaired?

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Lucas S. Broster

2012-03-01

Full Text Available We review recent work on emotional memory enhancement in older adults and patients with mild cognitive impairment or Alzheimer dementia and evaluate the viability of incorporating emotional components into cognitive rehabilitation for these groups. First, we identify converging evidence regarding the effects of emotional valence on working memory in healthy aging. Second, we introduce work that suggests a more complex role for emotional memory enhancement in aging and identify a model capable of unifying disparate research findings. Third, we identify neuroimaging evidence that the amygdala may play a key role in mediating emotional memory enhancement in mild cognitive impairment and early Alzheimer dementia. Finally, we assess the theoretical feasibility of incorporating emotional content into cognitive rehabilitation given all available evidence.

Dynamic working memory performance in individuals with single-domain amnestic mild cognitive impairment.

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Guild, Emma B; Vasquez, Brandon P; Maione, Andrea M; Mah, Linda; Ween, Jon; Anderson, Nicole D

2014-01-01

Previous studies have observed poorer working memory performance in individuals with amnestic mild cognitive impairment than in healthy older adults. It is unclear, however, whether these difficulties are true only of the multiple-domain clinical subtype in whom poorer executive functioning is common. The current study examined working memory, as measured by the self-ordered pointing task (SOPT) and an n-back task, in healthy older adults and adults with single-domain amnestic mild cognitive impairment (aMCI). Individuals with single-domain aMCI committed more errors and required longer to develop an organizational strategy on the SOPT. The single-domain aMCI group did not differ from healthy older adults on the 1-back or 2-back, but had poorer discrimination on the 3-back task. This is, to our knowledge, the first characterization of dynamic working memory performance in a single-domain aMCI group. These results lend support for the idea that clinical amnestic MCI subtypes may reflect different stages on a continuum of progression to dementia and question whether standardized measures of working memory (span tasks) are sensitive enough to capture subtle changes in performance.
Select overexpression of homer1a in dorsal hippocampus impairs spatial working memory

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Tansu Celikel

2007-10-01

Full Text Available Long Homer proteins forge assemblies of signaling components involved in glutamate receptor signaling in postsynaptic excitatory neurons, including those underlying synaptic transmission and plasticity. The short immediate-early gene (IEG Homer1a can dynamically uncouple these physical associations by functional competition with long Homer isoforms. To examine the consequences of Homer1amediated uncoupling for synaptic plasticity and behavior, we generated forebrain-specific tetracycline (tet controlled expression of Venus-tagged Homer1a (H1aV in mice. We report that sustained overexpression of H1aV impaired spatial working but not reference memory. Most notably, a similar impairment was observed when H1aV expression was restricted to the dorsal hippocampus (HP, which identifies this structure as the principal cortical area for spatial working memory. Interestingly, H1aV overexpression also abolished maintenance of CA3-CA1 long-term potentiation (LTP. These impairments, generated by sustained high Homer1a levels, identify a requirement for long Homer forms in synaptic plasticity and temporal encoding of spatial memory.
Working memory and sentence comprehension of Hong Kong Chinese children with specific language impairment.

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Siu, Elaine; Man, David W K

2006-09-01

Children with Specific Language Impairment present with delayed language development, but do not have a history of hearing impairment, mental deficiency, or associated social or behavioral problems. Non-word repetition was suggested as an index to reflect the capacity of phonological working memory. There is a paucity of such studies among Hong Kong Chinese children. This preliminary study aimed to examine the relationship between phonological working memory and Specific Language Impairment, through the processes of non-word repetition and sentence comprehension, of children with Specific Language Impairment and pre-school children with normal language development. Both groups of children were screened by a standardized language test. A list of Cantonese (the commonest dialect used in Hong Kong) multisyllabic nonsense utterances and a set of 18 sentences were developed for this study. t-tests and Pearson correlation were used to study the relationship between non-word repetition, working memory and specific language impairment. Twenty-three pre-school children with Specific Language Impairment (mean age = 68.30 months; SD = 6.90) and another 23 pre-school children (mean age = 67.30 months; SD = 6.16) participated in the study. Significant difference performance was found between the Specific Language Impairment group and normal language group in the multisyllabic nonsense utterances repetition task and the sentence comprehension task. Length effect was noted in Specific Language Impairment group children, which is consistent with the findings of other literature. In addition, correlations were also observed between the number of nonsense utterances repeated and the number of elements comprehended. Cantonese multisyllabic nonsense utterances might be worth further developing as a screening tool for the early detection of children with Specific Language Impairment.
Acute cannabinoids impair working memory through astroglial CB1 receptor modulation of hippocampal LTD.

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Han, Jing; Kesner, Philip; Metna-Laurent, Mathilde; Duan, Tingting; Xu, Lin; Georges, Francois; Koehl, Muriel; Abrous, Djoher Nora; Mendizabal-Zubiaga, Juan; Grandes, Pedro; Liu, Qingsong; Bai, Guang; Wang, Wei; Xiong, Lize; Ren, Wei; Marsicano, Giovanni; Zhang, Xia

2012-03-02

Impairment of working memory is one of the most important deleterious effects of marijuana intoxication in humans, but its underlying mechanisms are presently unknown. Here, we demonstrate that the impairment of spatial working memory (SWM) and in vivo long-term depression (LTD) of synaptic strength at hippocampal CA3-CA1 synapses, induced by an acute exposure of exogenous cannabinoids, is fully abolished in conditional mutant mice lacking type-1 cannabinoid receptors (CB(1)R) in brain astroglial cells but is conserved in mice lacking CB(1)R in glutamatergic or GABAergic neurons. Blockade of neuronal glutamate N-methyl-D-aspartate receptors (NMDAR) and of synaptic trafficking of glutamate α-amino-3-hydroxy-5-methyl-isoxazole propionic acid receptors (AMPAR) also abolishes cannabinoid effects on SWM and LTD induction and expression. We conclude that the impairment of working memory by marijuana and cannabinoids is due to the activation of astroglial CB(1)R and is associated with astroglia-dependent hippocampal LTD in vivo. Copyright Â© 2012 Elsevier Inc. All rights reserved.
The strengths and weaknesses in verbal short-term memory and visual working memory in children with hearing impairment and additional language learning difficulties.

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Willis, Suzi; Goldbart, Juliet; Stansfield, Jois

2014-07-01

To compare verbal short-term memory and visual working memory abilities of six children with congenital hearing-impairment identified as having significant language learning difficulties with normative data from typically hearing children using standardized memory assessments. Six children with hearing loss aged 8-15 years were assessed on measures of verbal short-term memory (Non-word and word recall) and visual working memory annually over a two year period. All children had cognitive abilities within normal limits and used spoken language as the primary mode of communication. The language assessment scores at the beginning of the study revealed that all six participants exhibited delays of two years or more on standardized assessments of receptive and expressive vocabulary and spoken language. The children with hearing-impairment scores were significantly higher on the non-word recall task than the "real" word recall task. They also exhibited significantly higher scores on visual working memory than those of the age-matched sample from the standardized memory assessment. Each of the six participants in this study displayed the same pattern of strengths and weaknesses in verbal short-term memory and visual working memory despite their very different chronological ages. The children's poor ability to recall single syllable words in relation to non-words is a clinical indicator of their difficulties in verbal short-term memory. However, the children with hearing-impairment do not display generalized processing difficulties and indeed demonstrate strengths in visual working memory. The poor ability to recall words, in combination with difficulties with early word learning may be indicators of children with hearing-impairment who will struggle to develop spoken language equal to that of their normally hearing peers. This early identification has the potential to allow for target specific intervention that may remediate their difficulties. Copyright © 2014. Published
Event-related potentials elicited during working memory are altered in mild cognitive impairment.

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López Zunini, Rocío A; Knoefel, Frank; Lord, Courtney; Dzuali, Fiatsogbe; Breau, Michael; Sweet, Lisa; Goubran, Rafik; Taler, Vanessa

2016-11-01

Persons with Mild Cognitive Impairment (MCI) can experience deficits in working memory. In the present study, we investigated working memory in persons with MCI and cognitively healthy older adults using event-related potentials (ERPs). Participants performed an n-back working memory task with baseline (0-back), low load (1-back), and high load (2-back) working memory conditions. MCI participants' performance was less accurate than that of healthy older adults in both the 1-back and 2-back conditions, and reaction times were longer in MCI than control participants in the 0-back, 1-back and 2-back conditions. ERP analyses revealed delayed P200 and N200 latencies and smaller P300 amplitudes in MCI relative to control participants in the 0-back, 1-back and 2-back conditions. Deterioration in working memory performance concomitant with marked electrophysiological alterations suggests that persons with MCI exhibit deficits in several cognitive processes that include early attention, stimulus discrimination and classification, and updating and manipulation of information held in working memory. Copyright © 2016 Elsevier B.V. All rights reserved.
Timing and gender determine if acute pain impairs working memory performance.

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Hood, Anna; Pulvers, Kim; Spady, Thomas J

2013-11-01

The effects of pain on memory are complex, and little is known about the vulnerability of working memory (WM) performance when individuals complete a WM test while concurrently experiencing pain. Here, we subjected 78 healthy nonsmoking participants to either acute pain or a control condition while we administered a WM test. In this context, we also tested WM 20 minutes after pain in order to determine if timing of pain affected WM performance, and assessed objective and subjective measures of pain. We hypothesized that pain would impair WM performance during pain. Further, women's WM performance would be impaired more than men. Importantly, there was an interaction between gender and condition, with women exposed to pain experiencing impairments during but not after the cold pressor task. Our data imply that timing and gender are critically important in whether acute pain is costly to WM performance. Our findings have interesting clinical, professional, and educational implications, and understanding the influence of pain could help to improve the interpretation of WM tests in these diverse settings. Results of this study support the growing body of work that attests to the detrimental effect of pain on WM performance. Further, this study provides new evidence that concurrently experiencing cold pressor pain impairs WM in regularly menstruating women and women taking a contraceptive. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.
Free recall behaviour in children with and without spelling impairment: the impact of working memory subcapacities.

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Malstädt, Nadine; Hasselhorn, Marcus; Lehmann, Martin

2012-11-01

This study examined supraspan free recall in children with and without spelling impairment. A repeated free recall task involving overt rehearsal and three computer-based adaptive working memory tasks were administered to 54 eight-year-old children. Children without spelling impairments tended to recall more items than did those children with spelling deficits. Video analyses revealed that recall behaviour was similar in impaired and unimpaired children, indicating that both groups applied similar learning activities. Group differences in number of recalled items were attributed to differences in working memory subcapacities between children with and without spelling impairment, especially with regard to central executive and phonological loop functioning. Copyright © 2012 John Wiley & Sons, Ltd.
Moving the hands and feet specifically impairs working memory for arm- and leg-related action words.

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Shebani, Zubaida; Pulvermüller, Friedemann

2013-01-01

Language and action systems of the human brain are functionally interwoven. Speaking about actions and understanding action-related speech sparks the motor system of the human brain and, conversely, motor system activation has an influence on the comprehension of action words and sentences. Although previous research has shown that motor systems become active when we understand language, a major question still remains whether these motor system activations are necessary for processing action words. We here report that rhythmic movements of either the hands or the feet lead to a differential impairment of working memory for concordant arm- and leg-related action words, with hand/arm movements predominantly impairing working memory for words used to speak about arm actions and foot/leg movements primarily impairing leg-related word memory. The resulting cross-over double dissociation demonstrates that body part specific and meaning-related processing resources in specific cortical motor systems are shared between overt movements and working memory for action-related words, thus documenting a genuine motor locus of semantic meaning. Copyright © 2011. Published by Elsevier Srl.
Assessing Working Memory in Children: The Comprehensive Assessment Battery for Children - Working Memory (CABC-WM).

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Cabbage, Kathryn; Brinkley, Shara; Gray, Shelley; Alt, Mary; Cowan, Nelson; Green, Samuel; Kuo, Trudy; Hogan, Tiffany P

2017-06-12

The Comprehensive Assessment Battery for Children - Working Memory (CABC-WM) is a computer-based battery designed to assess different components of working memory in young school-age children. Working memory deficits have been identified in children with language-based learning disabilities, including dyslexia 1 , 2 and language impairment 3 , 4 , but it is not clear whether these children exhibit deficits in subcomponents of working memory, such as visuospatial or phonological working memory. The CABC-WM is administered on a desktop computer with a touchscreen interface and was specifically developed to be engaging and motivating for children. Although the long-term goal of the CABC-WM is to provide individualized working memory profiles in children, the present study focuses on the initial success and utility of the CABC-WM for measuring central executive, visuospatial, phonological loop, and binding constructs in children with typical development. Immediate next steps are to administer the CABC-WM to children with specific language impairment, dyslexia, and comorbid specific language impairment and dyslexia.
Postencephalitic amnesia with long term-working memory impairment: A case report

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Beatriz Baldivia

Full Text Available Abstract Herpes simplex virus encephalitis (HSVE is an inflammation of the brain parenchyma caused by virus, leading to focal necrosis in medial temporal lobes, hippocampal complex and basal forebrain. Cognitively, HSVE is associated to many dysfunctions which vary according to the extent of the lesion. Episodic memory impairment is the most common sequelae following HSVE episodes, although others can occur. The aim of this case report was to describe the cognitive profile of a 42 year-old man who had extensive bilateral damage to the medial temporal lobe, insular bilateral and orbitofrontal cortices due to HSVE. Severe anterograde and retrograde amnesia, naming deficits, perseverative behaviors and confabulations were observed on neuropsychological assessment. We discussed the concept of long term-working memory based on this evaluation. These cognitive impairments corroborated HSVE previous findings in the literature.
High-calorie food-cues impair working memory performance in high and low food cravers.

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Meule, Adrian; Skirde, Ann Kathrin; Freund, Rebecca; Vögele, Claus; Kübler, Andrea

2012-10-01

The experience of food craving can lead to cognitive impairments. Experimentally induced chocolate craving exhausts cognitive resources and, therefore, impacts working memory, particularly in trait chocolate cravers. In the current study, we investigated the effects of exposure to food-cues on working memory task performance in a group with frequent and intense (high cravers, n=28) and less pronounced food cravings (low cravers, n=28). Participants performed an n-back task that contained either pictures of high-calorie sweets, high-calorie savory foods, or neutral objects. Current subjective food craving was assessed before and after the task. All participants showed slower reaction times and made more omission errors in response to food-cues, particularly savory foods. There were no differences in task performance between groups. State cravings did not differ between groups before the task, but increased more in high cravers compared to low cravers during the task. Results support findings about food cravings impairing visuo-spatial working memory performance independent of trait cravings. They further show that this influence is not restricted to chocolate, but also applies to high-calorie savory foods. Limiting working memory capacity may be especially crucial in persons who are more prone to high-calorie food-cues and experience such cravings habitually. Copyright © 2012 Elsevier Ltd. All rights reserved.
Shared neuroanatomical substrates of impaired phonological working memory across reading disability and autism

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Lu, Chunming; Qi, Zhenghan; Harris, Adrianne; Weil, Lisa Wisman; Han, Michelle; Halverson, Kelly; Perrachione, Tyler K.; Kjelgaard, Margaret; Wexler, Kenneth; Tager-Flusberg, Helen; Gabrieli, John D. E.

2016-01-01

Background Individuals with reading disability and individuals with autism spectrum disorder (ASD) are characterized, respectively, by their difficulties in reading and social communication, but both groups often have impaired phonological working memory (PWM). It is not known whether the impaired PWM reflects distinct or shared neuroanatomical abnormalities in these two diagnostic groups. Methods White-matter structural connectivity via diffusion weighted imaging was examined in 64 children,...
Children with Chromosome 22q11.2 Deletion Syndrome Exhibit Impaired Spatial Working Memory

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Wong, Ling M.; Riggins, Tracy; Harvey, Danielle; Cabaral, Margarita; Simon, Tony J.

2014-01-01

Individuals with chromosome 22q11.2 deletion syndrome (22q11.2DS) have been shown to have impairments in processing spatiotemporal information. The authors examined whether children with 22q11.2DS exhibit impairments in spatial working memory performance due to these weaknesses, even when controlling for maintenance of attention. Children with…
Prevalence and diagnostic validity of motivational impairments and deficits in visuospatial short-term memory and working memory in ADHD subtypes

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Dovis, S.; van der Oord, S.; Huizenga, H.M.; Wiers, R.W.; Prins, P.J.M.

2015-01-01

Deficits in working memory (WM) and reinforcement sensitivity are thought to give rise to symptoms in the combined (ADHD-C) and inattentive subtype (ADHD-I) of ADHD. Children with ADHD are especially impaired on visuospatial WM, which is composed of short-term memory (STM) and a central executive.
Associative working memory and subsequent episodic memory in Alzheimer's disease.

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Geldorp, B. van; Konings, E.P.; Tilborg, I.A. Van; Kessels, R.P.C.

2012-01-01

Recent studies indicate deficits in associative working memory in patients with medial-temporal lobe amnesia. However, it is unclear whether these deficits reflect working memory processing or are due to hippocampally mediated long-term memory impairment. We investigated associative working memory
Associative working memory and subsequent episodic memory in Alzheimer's disease

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Geldorp, B. van; Konings, E.P.C.; Tilborg, I.A.D.A. van; Kessels, R.P.C.

2012-01-01

Recent studies indicate deficits in associative working memory in patients with medial-temporal lobe amnesia. However, it is unclear whether these deficits reflect working memory processing or are due to hippocampally mediated long-term memory impairment. We investigated associative working memory
Novel fMRI working memory paradigm accurately detects cognitive impairment in Multiple Sclerosis

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Nelson, Flavia; Akhtar, Mohammad A.; Zúñiga, Edward; Perez, Carlos A.; Hasan, Khader M.; Wilken, Jeffrey; Wolinsky, Jerry S.; Narayana, Ponnada A.; Steinberg, Joel L.

2016-01-01

Background Cognitive impairment (CI) cannot be diagnosed by MRI. Functional MRI (fMRI) paradigms such as the immediate/delayed memory task (I/DMT), detect varying degrees of working memory. Preliminary findings using I/DMT, showed differences in Blood Oxygenation Level Dependent (BOLD) activation between impaired (MSCI, n=12) and non-impaired (MSNI, n=9) MS patients. Objectives To confirm CI detection based on I/DMT’ BOLD activation in a larger cohort of MS patients. The role of T2 lesion volume (LV) and EDSS in magnitude of BOLD signal were also sought. Methods Fifty patients [EDSS mean (m) = 3.2, DD m =12 yr., age m =40yr.] underwent the Minimal Assessment of Cognitive Function in MS (MACFIMS) and the I/DMT. Working-memory activation (WMa) represents BOLD signal during DMT minus signal during IMT. CI was based on MACFIMS. Results 10 MSNI, 30 MSCI and 4 borderline patients were included in analyses. ANOVA showed MSNI had significantly greater WMa than MSCI, in the left (L) prefrontal cortex and L supplementary motor area (p = 0.032). Regression analysis showed significant inverse correlations between WMa and T2 LV/EDSS in similar areas (p = 0.005, 0.004 respectively). Conclusion I/DMT-based BOLD activation detects CI in MS, larger studies are needed to confirm these findings. PMID:27613119
Spatial working memory in aging and mild cognitive impairment: effects of task load and contextual cueing.

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Kessels, Roy P C; Meulenbroek, Olga; Fernández, Guillén; Olde Rikkert, Marcel G M

2010-09-01

Mild Cognitive Impairment (MCI) is characterized by episodic memory deficits, while aspects of working memory may also be implicated, but studies into this latter domain are scarce and results are inconclusive. Using a computerized search paradigm, this study compares 25 young adults, 25 typically aging older adults and 15 amnestic MCI patients as to their working-memory capacities for object-location information and potential differential effects of memory load and additional context cues. An age-related deficit in visuospatial working-memory maintenance was found that became more pronounced with increasing task demands. The MCI group additionally showed reduced maintenance of bound information, i.e., object-location associations, again especially at elevated memory load. No effects of contextual cueing were found. The current findings indicate that working memory should be considered when screening patients for suspected MCI and monitoring its progression.
Working Memory, Long-Term Memory, and Medial Temporal Lobe Function

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Jeneson, Annette; Squire, Larry R.

2012-01-01

Early studies of memory-impaired patients with medial temporal lobe (MTL) damage led to the view that the hippocampus and related MTL structures are involved in the formation of long-term memory and that immediate memory and working memory are independent of these structures. This traditional idea has recently been revisited. Impaired performance…

Working Memory and Neurofeedback.

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YuLeung To, Eric; Abbott, Kathy; Foster, Dale S; Helmer, D'Arcy

2016-01-01

Impairments in working memory are typically associated with impairments in other cognitive faculties such as attentional processes and short-term memory. This paper briefly introduces neurofeedback as a treatment modality in general, and, more specifically, we review several of the current modalities successfully used in neurofeedback (NF) for the treatment of working memory deficits. Two case studies are presented to illustrate how neurofeedback is applied in treatment. The development of Low Resolution Electromagnetic Tomography (LORETA) and its application in neurofeedback now makes it possible to specifically target deep cortical/subcortical brain structures. Developments in neuroscience concerning neural networks, combined with highly specific yet practical NF technologies, makes neurofeedback of particular interest to neuropsychological practice, including the emergence of specific methodologies for treating very difficult working memory (WM) problems.
Spatial working memory in aging and mild cognitive impairment: effects of task load and contextual cueing.

NARCIS (Netherlands)

Kessels, R.P.C.; Meulenbroek, O.V.; Fernandez, G.S.E.; Olde Rikkert, M.G.M.

2010-01-01

Mild Cognitive Impairment (MCI) is characterized by episodic memory deficits, while aspects of working memory may also be implicated, but studies into this latter domain are scarce and results are inconclusive. Using a computerized search paradigm, this study compares 25 young adults, 25 typically
Spatial Working Memory in Aging and Mild Cognitive Impairment: Effects of Task Load and Contextual Cueing

NARCIS (Netherlands)

Kessels, R.P.C.; Meulenbroek, O.V.; Fernandez, G.S.E.; Olde Rikkert, M.G.M.

2010-01-01

Mild Cognitive Impairment (MCI) is characterized by episodic memory deficits, while aspects of working memory may also be implicated, but studies into this latter domain are scarce and results are inconclusive. Using a computerized search paradigm, this study compares 25 young adults, 25 typically
Happiness increases verbal and spatial working memory capacity where sadness does not: Emotion, working memory and executive control.

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Storbeck, Justin; Maswood, Raeya

2016-08-01

The effects of emotion on working memory and executive control are often studied in isolation. Positive mood enhances verbal and impairs spatial working memory, whereas negative mood enhances spatial and impairs verbal working memory. Moreover, positive mood enhances executive control, whereas negative mood has little influence. We examined how emotion influences verbal and spatial working memory capacity, which requires executive control to coordinate between holding information in working memory and completing a secondary task. We predicted that positive mood would improve both verbal and spatial working memory capacity because of its influence on executive control. Positive, negative and neutral moods were induced followed by completing a verbal (Experiment 1) or spatial (Experiment 2) working memory operation span task to assess working memory capacity. Positive mood enhanced working memory capacity irrespective of the working memory domain, whereas negative mood had no influence on performance. Thus, positive mood was more successful holding information in working memory while processing task-irrelevant information, suggesting that the influence mood has on executive control supersedes the independent effects mood has on domain-specific working memory.
A single night of sleep loss impairs objective but not subjective working memory performance in a sex-dependent manner.

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Rångtell, Frida H; Karamchedu, Swathy; Andersson, Peter; Liethof, Lisanne; Olaya Búcaro, Marcela; Lampola, Lauri; Schiöth, Helgi B; Cedernaes, Jonathan; Benedict, Christian

2018-01-31

Acute sleep deprivation can lead to judgement errors and thereby increases the risk of accidents, possibly due to an impaired working memory. However, whether the adverse effects of acute sleep loss on working memory are modulated by auditory distraction in women and men are not known. Additionally, it is unknown whether sleep loss alters the way in which men and women perceive their working memory performance. Thus, 24 young adults (12 women using oral contraceptives at the time of investigation) participated in two experimental conditions: nocturnal sleep (scheduled between 22:30 and 06:30 hours) versus one night of total sleep loss. Participants were administered a digital working memory test in which eight-digit sequences were learned and retrieved in the morning after each condition. Learning of digital sequences was accompanied by either silence or auditory distraction (equal distribution among trials). After sequence retrieval, each trial ended with a question regarding how certain participants were of the correctness of their response, as a self-estimate of working memory performance. We found that sleep loss impaired objective but not self-estimated working memory performance in women. In contrast, both measures remained unaffected by sleep loss in men. Auditory distraction impaired working memory performance, without modulation by sleep loss or sex. Being unaware of cognitive limitations when sleep-deprived, as seen in our study, could lead to undesirable consequences in, for example, an occupational context. Our findings suggest that sleep-deprived young women are at particular risk for overestimating their working memory performance. © 2018 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.
Working memory, long-term memory, and medial temporal lobe function

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Jeneson, Annette; Squire, Larry R.

2012-01-01

Early studies of memory-impaired patients with medial temporal lobe (MTL) damage led to the view that the hippocampus and related MTL structures are involved in the formation of long-term memory and that immediate memory and working memory are independent of these structures. This traditional idea has recently been revisited. Impaired performance in patients with MTL lesions on tasks with short retention intervals, or no retention interval, and neuroimaging findings with similar tasks have been interpreted to mean that the MTL is sometimes needed for working memory and possibly even for visual perception itself. We present a reappraisal of this interpretation. Our main conclusion is that, if the material to be learned exceeds working memory capacity, if the material is difficult to rehearse, or if attention is diverted, performance depends on long-term memory even when the retention interval is brief. This fundamental notion is better captured by the terms subspan memory and supraspan memory than by the terms short-term memory and long-term memory. We propose methods for determining when performance on short-delay tasks must depend on long-term (supraspan) memory and suggest that MTL lesions impair performance only when immediate memory and working memory are insufficient to support performance. In neuroimaging studies, MTL activity during encoding is influenced by the memory load and correlates positively with long-term retention of the material that was presented. The most parsimonious and consistent interpretation of all the data is that subspan memoranda are supported by immediate memory and working memory and are independent of the MTL. PMID:22180053
Inhibition of connexin43 hemichannels impairs spatial short-term memory without affecting spatial working memory

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Laura Walrave

2016-12-01

Full Text Available Astrocytes are active players in higher brain function as they can release gliotransmitters, which are essential for synaptic plasticity. Various mechanisms have been proposed for gliotransmission, including vesicular mechanisms as well as non-vesicular ones, for example by passive diffusion via connexin hemichannels (HCs. We here investigated whether interfering with connexin43 (Cx43 HCs influenced hippocampal spatial memory. We made use of the peptide Gap19 that blocks HCs but not gap junction channels and is specific for Cx43. To this end, we microinfused transactivator of transcription linked Gap19 (TAT-Gap19 into the brain ventricle of male NMRI mice and assessed spatial memory in a Y maze. We found that the in vivo blockade of Cx43 HCs did not affect the locomotor activity or spatial working memory in a spontaneous alternation Y maze task. Cx43 blockade did however significantly impair the spatial short-term memory in a delayed spontaneous alternation Y maze task. These results indicate that Cx43 HCs play a role in spatial short-term memory.
Maintenance and manipulation of information in schizophrenia: further evidence for impairment in the central executive component of working memory.

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Kim, Junghoon; Glahn, David C; Nuechterlein, Keith H; Cannon, Tyrone D

2004-06-01

Impairments in working memory (WM) have been proposed to underlie various cognitive and functional impairments in schizophrenia. However, the nature and extent of the dysfunction remain unclear. The present study attempted to examine the integrity of sub-components of working memory in schizophrenia within the framework of the multiple-component working memory model proposed by Baddeley. Two sets of visuospatial and verbal delayed-response tasks were developed which had comparable formats and difficulties across domains. In Experiment 1, demands on the central executive (CE) were manipulated by requiring subjects either (1) to simultaneously maintain and transform information (maintenance-and-manipulation condition) or (2) just to maintain this information (maintenance-only condition). In Experiment 2, the amount of information to be maintained over the delay was parametrically varied to evaluate demands on the temporary maintenance component of working memory. Patients (N=16) performed worse than controls (N=16) in both conditions of Experiment 1; however, simultaneous maintenance and manipulation was associated with a significantly greater performance reduction in the patients. In Experiment 2, both patients (N=15) and controls (N=15) declined in performance, at equivalent rates, with increasing memory load. Parallel findings were observed for the verbal and visuospatial tasks. These results suggest that while both maintenance and central executive aspects of working memory are impaired in schizophrenic patients, the central executive may be more severely affected.
[Working memory for music in patients with mild cognitive impairment and early stage Alzheimer's disease].

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Kerer, Manuela; Marksteiner, Josef; Hinterhuber, Hartmann; Mazzola, Guerino; Kemmler, Georg; Bliem, Harald R; Weiss, Elisabeth M

2013-01-01

A variety of studies demonstrated that some forms of memory for music are spared in dementia, but only few studies have investigated patients with early stages of dementia. In this pilot-study we tested working memory for music in patients with mild cognitive impairment (MCI) and early stage Alzheimer's disease (AD) with a newly created test. The test probed working memory using 7 gradually elongated tone-lines and 6 chords which were each followed by 3 similar items and 1 identical item. The participants of the study, namely 10 patients with MCI, 10 patients with early stage AD and 23 healthy subjects were instructed to select the identical tone-line or chord. Subjects with MCI and early AD showed significantly reduced performance than controls in most of the presented tasks. In recognizing chords MCI- participants surprisingly showed an unimpaired performance. The gradual increase of the impairment during the preclinical phase of AD seems to spare this special ability in MCI.
Working memory span in mild cognitive impairment. Influence of processing speed and cognitive reserve.

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Facal, David; Juncos-Rabadán, Onésimo; Pereiro, Arturo X; Lojo-Seoane, Cristina

2014-04-01

Mild cognitive impairment (MCI) often includes episodic memory impairment, but can also involve other types of cognitive decline. Although previous studies have shown poorer performance of MCI patients in working memory (WM) span tasks, different MCI subgroups were not studied. In the present exploratory study, 145 participants underwent extensive cognitive evaluation, which included three different WM span tasks, and were classified into the following groups: multiple-domain amnestic MCI (mda-MCI), single-domain amnestic MCI (sda-MCI), and controls. General linear model was conducted by considering the WM span tasks as the within-subject factor; the group (mda-MCI, sda-MCI, and controls) as the inter-subject factor; and processing speed, vocabulary and age as covariates. Multiple linear regression models were also used to test the influence of processing speed, vocabulary, and other cognitive reserve (CR) proxies. Results indicate different levels of impairment of WM, with more severe impairment in mda-MCI patients. The differences were still present when processing resources and CR were controlled. Between-group differences can be understood as a manifestation of the greater severity and widespread memory impairment in mda-MCI patients and may contribute to a better understanding of continuum from normal controls to mda-MCI patients. Processing speed and CR have a limited influence on WM scores, reducing but not removing differences between groups.
Assessing Working Memory in Children: The Comprehensive Assessment Battery for Children – Working Memory (CABC-WM)

OpenAIRE

Cabbage, Kathryn; Brinkley, Shara; Gray, Shelley; Alt, Mary; Cowan, Nelson; Green, Samuel; Kuo, Trudy; Hogan, Tiffany P.

2017-01-01

The Comprehensive Assessment Battery for Children - Working Memory (CABC-WM) is a computer-based battery designed to assess different components of working memory in young school-age children. Working memory deficits have been identified in children with language-based learning disabilities, including dyslexia1 2 and language impairment3 4, but it is not clear whether these children exhibit deficits in subcomponents of working memory, such as visuospatial or phonological working memory. The C...
Intrahemispheric theta rhythm desynchronization impairs working memory.

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Alekseichuk, Ivan; Pabel, Stefanie Corinna; Antal, Andrea; Paulus, Walter

2017-01-01

There is a growing interest in large-scale connectivity as one of the crucial factors in working memory. Correlative evidence has revealed the anatomical and electrophysiological players in the working memory network, but understanding of the effective role of their connectivity remains elusive. In this double-blind, placebo-controlled study we aimed to identify the causal role of theta phase connectivity in visual-spatial working memory. The frontoparietal network was over- or de-synchronized in the anterior-posterior direction by multi-electrode, 6 Hz transcranial alternating current stimulation (tACS). A decrease in memory performance and increase in reaction time was caused by frontoparietal intrahemispheric desynchronization. According to the diffusion drift model, this originated in a lower signal-to-noise ratio, known as the drift rate index, in the memory system. The EEG analysis revealed a corresponding decrease in phase connectivity between prefrontal and parietal areas after tACS-driven desynchronization. The over-synchronization did not result in any changes in either the behavioral or electrophysiological levels in healthy participants. Taken together, we demonstrate the feasibility of manipulating multi-site large-scale networks in humans, and the disruptive effect of frontoparietal desynchronization on theta phase connectivity and visual-spatial working memory.
Impairment on a self-ordered working memory task in patients with early-acquired hippocampal atrophy.

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Geva, Sharon; Cooper, Janine M; Gadian, David G; Mishkin, Mortimer; Vargha-Khadem, Faraneh

2016-08-01

One of the features of both adult-onset and developmental forms of amnesia resulting from bilateral medial temporal lobe damage, or even from relatively selective damage to the hippocampus, is the sparing of working memory. Recently, however, a number of studies have reported deficits on working memory tasks in patients with damage to the hippocampus and in macaque monkeys with neonatal hippocampal lesions. These studies suggest that successful performance on working memory tasks with high memory load require the contribution of the hippocampus. Here we compared performance on a working memory task (the Self-ordered Pointing Task), between patients with early onset hippocampal damage and a group of healthy controls. Consistent with the findings in the monkeys with neonatal lesions, we found that the patients were impaired on the task, but only on blocks of trials with intermediate memory load. Importantly, only intermediate to high memory load blocks yielded significant correlations between task performance and hippocampal volume. Additionally, we found no evidence of proactive interference in either group, and no evidence of an effect of time since injury on performance. We discuss the role of the hippocampus and its interactions with the prefrontal cortex in serving working memory. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Impairment on a self-ordered working memory task in patients with early-acquired hippocampal atrophy

Directory of Open Access Journals (Sweden)

Sharon Geva

2016-08-01

Full Text Available One of the features of both adult-onset and developmental forms of amnesia resulting from bilateral medial temporal lobe damage, or even from relatively selective damage to the hippocampus, is the sparing of working memory. Recently, however, a number of studies have reported deficits on working memory tasks in patients with damage to the hippocampus and in macaque monkeys with neonatal hippocampal lesions. These studies suggest that successful performance on working memory tasks with high memory load require the contribution of the hippocampus. Here we compared performance on a working memory task (the Self-ordered Pointing Task, between patients with early onset hippocampal damage and a group of healthy controls. Consistent with the findings in the monkeys with neonatal lesions, we found that the patients were impaired on the task, but only on blocks of trials with intermediate memory load. Importantly, only intermediate to high memory load blocks yielded significant correlations between task performance and hippocampal volume. Additionally, we found no evidence of proactive interference in either group, and no evidence of an effect of time since injury on performance. We discuss the role of the hippocampus and its interactions with the prefrontal cortex in serving working memory.
Free Recall Behaviour in Children with and without Spelling Impairment: The Impact of Working Memory Subcapacities

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Malstadt, Nadine; Hasselhorn, Marcus; Lehmann, Martin

2012-01-01

This study examined supraspan free recall in children with and without spelling impairment. A repeated free recall task involving overt rehearsal and three computer-based adaptive working memory tasks were administered to 54 eight-year-old children. Children without spelling impairments tended to recall more items than did those children with…
Prevalence and diagnostic validity of motivational impairments and deficits in visuospatial short-term memory and working memory in ADHD subtypes.

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Dovis, Sebastiaan; Van der Oord, Saskia; Huizenga, Hilde M; Wiers, Reinout W; Prins, Pier J M

2015-05-01

Deficits in working memory (WM) and reinforcement sensitivity are thought to give rise to symptoms in the combined (ADHD-C) and inattentive subtype (ADHD-I) of ADHD. Children with ADHD are especially impaired on visuospatial WM, which is composed of short-term memory (STM) and a central executive. Although deficits in visuospatial WM and reinforcement sensitivity appear characteristic of children with ADHD on a group-level, the prevalence and diagnostic validity of these impairments is still largely unknown. Moreover, studies investigating this did not control for the interaction between motivational impairments and cognitive performance in children with ADHD, and did not differentiate between ADHD subtypes. Visuospatial WM and STM tasks were administered in a standard (feedback-only) and a high-reinforcement (feedback + 10 euros) condition, to 86 children with ADHD-C, 27 children with ADHD-I (restrictive subtype), and 62 typically developing controls (aged 8-12). Reinforcement sensitivity was indexed as the difference in performance between the reinforcement conditions. WM and STM impairments were most prevalent in ADHD-C. In ADHD-I, only WM impairments, not STM impairments, were more prevalent than in controls. Motivational impairments were not common (22% impaired) and equally prevalent in both subtypes. Memory and motivation were found to represent independent neuropsychological domains. Impairment on WM, STM, and/or motivation was associated with more inattention symptoms, medication-use, and lower IQ scores. Similar results were found for analyses of diagnostic validity. The majority of children with ADHD-C is impaired on visuospatial WM. In ADHD-I, STM impairments are not more common than in controls. Within both ADHD subtypes only a minority has an abnormal sensitivity to reinforcement.
Extensive Lesions of Cholinergic Basal Forebrain Neurons Do Not Impair Spatial Working Memory

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Vuckovich, Joseph A.; Semel, Mara E.; Baxter, Mark G.

2004-01-01

A recent study suggests that lesions to all major areas of the cholinergic basal forebrain in the rat (medial septum, horizontal limb of the diagonal band of Broca, and nucleus basalis magnocellularis) impair a spatial working memory task. However, this experiment used a surgical technique that may have damaged cerebellar Purkinje cells. The…
Novel fMRI working memory paradigm accurately detects cognitive impairment in multiple sclerosis.

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Nelson, Flavia; Akhtar, Mohammad A; Zúñiga, Edward; Perez, Carlos A; Hasan, Khader M; Wilken, Jeffrey; Wolinsky, Jerry S; Narayana, Ponnada A; Steinberg, Joel L

2017-05-01

Cognitive impairment (CI) cannot be diagnosed by magnetic resonance imaging (MRI). Functional magnetic resonance imaging (fMRI) paradigms, such as the immediate/delayed memory task (I/DMT), detect varying degrees of working memory (WM). Preliminary findings using I/DMT showed differences in blood oxygenation level dependent (BOLD) activation between impaired (MSCI, n = 12) and non-impaired (MSNI, n = 9) multiple sclerosis (MS) patients. The aim of the study was to confirm CI detection based on I/DMT BOLD activation in a larger cohort of MS patients. The role of T2 lesion volume (LV) and Expanded Disability Status Scale (EDSS) in magnitude of BOLD signal was also sought. A total of 50 patients (EDSS mean ( m) = 3.2, disease duration (DD) m = 12 years, and age m = 40 years) underwent the Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) and I/DMT. Working memory activation (WMa) represents BOLD signal during DMT minus signal during IMT. CI was based on MACFIMS. A total of 10 MSNI, 30 MSCI, and 4 borderline patients were included in the analyses. Analysis of variance (ANOVA) showed MSNI had significantly greater WMa than MSCI, in the left prefrontal cortex and left supplementary motor area ( p = 0.032). Regression analysis showed significant inverse correlations between WMa and T2 LV/EDSS in similar areas ( p = 0.005, 0.004, respectively). I/DMT-based BOLD activation detects CI in MS. Larger studies are needed to confirm these findings.
Assessment and Treatment of Short-Term and Working Memory Impairments in Stroke Aphasia: A Practical Tutorial

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Salis, Christos; Kelly, Helen; Code, Chris

2015-01-01

Background: Aphasia following stroke refers to impairments that affect the comprehension and expression of spoken and/or written language, and co-occurring cognitive deficits are common. In this paper we focus on short-term and working memory impairments that impact on the ability to retain and manipulate auditory-verbal information. Evidence from…
Component deficits of visual neglect: "Magnetic" attraction of attention vs. impaired spatial working memory.

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Toba, Monica N; Rabuffetti, Marco; Duret, Christophe; Pradat-Diehl, Pascale; Gainotti, Guido; Bartolomeo, Paolo

2018-01-31

Visual neglect is a disabling consequence of right hemisphere damage, whereby patients fail to detect left-sided objects. Its precise mechanisms are debated, but there is some consensus that distinct component deficits may variously associate and interact in different patients. Here we used a touch-screen based procedure to study two putative component deficits of neglect, rightward "magnetic" attraction of attention and impaired spatial working memory, in a group of 47 right brain-damaged patients, of whom 33 had signs of left neglect. Patients performed a visual search task on three distinct conditions, whereby touched targets could (1) be tagged, (2) disappear or (3) show no change. Magnetic attraction of attention was defined as more left neglect on the tag condition than on the disappear condition, where right-sided disappeared targets could not capture patients' attention. Impaired spatial working memory should instead produce more neglect on the no change condition, where no external cue indicated that a target had already been explored, than on the tag condition. Using a specifically developed analysis algorithm, we identified significant differences of performance between the critical conditions. Neglect patients as a group performed better on the disappear condition than on the no change condition and also better in the tag condition comparing with the no change condition. No difference was found between the tag condition and the disappear condition. Some of our neglect patients had dissociated patterns of performance, with predominant magnetic attraction or impaired spatial working memory. Anatomical results issued from both grey matter analysis and fiber tracking were consistent with the typical patterns of fronto-parietal and occipito-frontal disconnection in neglect, but did not identify lesional patterns specifically associated with one or another deficit, thus suggesting the possible co-localization of attentional and working memory processes in

Working memory and organizational skills problems in ADHD.

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Kofler, Michael J; Sarver, Dustin E; Harmon, Sherelle L; Moltisanti, Allison; Aduen, Paula A; Soto, Elia F; Ferretti, Nicole

2018-01-01

This study tested model-driven predictions regarding working memory's role in the organizational problems associated with ADHD. Children aged 8-13 (M = 10.33, SD = 1.42) with and without ADHD (N = 103; 39 girls; 73% Caucasian/Non-Hispanic) were assessed on multiple, counterbalanced working memory tasks. Parents and teachers completed norm-referenced measures of organizational problems (Children's Organizational Skills Scale; COSS). Results confirmed large magnitude working memory deficits (d = 1.24) and organizational problems in ADHD (d = 0.85). Bias-corrected, bootstrapped conditional effects models linked impaired working memory with greater parent- and teacher-reported inattention, hyperactivity/impulsivity, and organizational problems. Working memory predicted organization problems across all parent and teacher COSS subscales (R 2 = .19-.23). Approximately 38%-57% of working memory's effect on organization problems was conveyed by working memory's association with inattentive behavior. Unique effects of working memory remained significant for both parent- and teacher-reported task planning, as well as for teacher-reported memory/materials management and overall organization problems. Attention problems uniquely predicted worse organizational skills. Hyperactivity was unrelated to parent-reported organizational skills, but predicted better teacher-reported task planning. Children with ADHD exhibit multisetting, broad-based organizational impairment. These impaired organizational skills are attributable in part to performance deficits secondary to working memory dysfunction, both directly and indirectly via working memory's role in regulating attention. Impaired working memory in ADHD renders it extraordinarily difficult for these children to consistently anticipate, plan, enact, and maintain goal-directed actions. © 2017 Association for Child and Adolescent Mental Health.
A Meta-Analysis of Working Memory Impairments in Children with Attention-Deficit/hyperactivity Disorder.

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Martinussen, Rhonda; Hayden, Jill; Hogg-Johnson, Sheilah; Tannock, Rosemary

2005-01-01

Objective: To determine the empirical evidence for deficits in working memory (WM) processes in children and adolescents with attention-deficit/hyperactivity disorder (ADHD). Method: Exploratory meta-analytic procedures were used to investigate whether children with ADHD exhibit WM impairments. Twenty-six empirical research studies published from…
Chronic Stress Impairs Prefrontal Cortex-Dependent Response Inhibition and Spatial Working Memory

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Mika, Agnieszka; Mazur, Gabriel J.; Hoffman, Ann N.; Talboom, Joshua S.; Bimonte-Nelson, Heather A.; Sanabria, Federico; Conrad, Cheryl D.

2012-01-01

Chronic stress leads to neurochemical and structural alterations in the prefrontal cortex (PFC) that correspond to deficits in PFC-mediated behaviors. The present study examined the effects of chronic restraint stress on response inhibition (using a response-withholding task, fixed-minimum interval schedule of reinforcement, or FMI), and working memory (using a radial arm water maze, RAWM). Adult male Sprague Dawley rats were first trained on the RAWM and subsequently trained on FMI. Following acquisition of FMI, rats were assigned to a restraint stress (6h/d/28d in wire mesh restrainers) or control condition. Immediately after chronic stress, rats were tested on FMI and subsequently on RAWM. FMI results suggest that chronic stress reduces response inhibition capacity and motivation to initiate the task on selective conditions when food reward was not obtained on the preceding trial. RAWM results suggest that chronic stress produces transient deficits in working memory without altering previously consolidated reference memory. Behavioral measures from FMI failed to correlate with metrics from RAWM except for one in which changes in FMI timing precision negatively correlated with changes in RAWM working memory errors for the controls, a finding that was not observed following chronic stress. Fisher’s r to z transformation revealed no significant differences between control and stress with correlation coefficients. These findings are the first to show that chronic stress impairs both response inhibition and working memory, two behaviors that have never been direct compared within the same animals following chronic stress, using FMI, an appetitive task, and RAWM, a non-appetitive task. PMID:22905921
Syntactic comprehension and working memory in children with specific language impairment, autism or Down syndrome.

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Fortunato-Tavares, Talita; Andrade, Claudia R F; Befi-Lopes, Debora; Limongi, Suelly O; Fernandes, Fernanda D M; Schwartz, Richard G

2015-07-01

This study examined syntactic assignment for predicates and reflexives as well as working memory effects in the sentence comprehension of children with Specific Language Impairment (SLI), Down syndrome (DS), high functioning Autism (HFA) and Typical Language Development (TLD). Fifty-seven children (35 boys and 22 girls) performed a computerised picture-selection sentence comprehension task. Predicate attachment and reflexive antecedent assignment (with working memory manipulations) were investigated. The results showed that SLI, HFA and DS children exhibited poorer overall performance than TLD children. Children with SLI exhibited similar performance to the DS and HFA children only when working memory demands were higher. We conclude that children with SLI, HFA and DS differ from children with TLD in their comprehension of predicate and reflexive structures where the knowledge of syntactic assignment is required. Working memory manipulation had different effects on syntactic comprehension depending on language disorder. Intelligence was not an explanatory factor for the differences observed in performance.
Stereotype threat can both enhance and impair older adults' memory.

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Barber, Sarah J; Mather, Mara

2013-12-01

Negative stereotypes about aging can impair older adults' memory via stereotype threat; however, the mechanisms underlying this phenomenon are unclear. In two experiments, we tested competing predictions derived from two theoretical accounts of stereotype threat: executive-control interference and regulatory fit. Older adults completed a working memory test either under stereotype threat about age-related memory declines or not under such threat. Monetary incentives were manipulated such that recall led to gains or forgetting led to losses. The executive-control-interference account predicts that stereotype threat decreases the availability of executive-control resources and hence should impair working memory performance. The regulatory-fit account predicts that threat induces a prevention focus, which should impair performance when gains are emphasized but improve performance when losses are emphasized. Results were consistent only with the regulatory-fit account. Although stereotype threat significantly impaired older adults' working memory performance when remembering led to gains, it significantly improved performance when forgetting led to losses.
Stress-Induced Impairment of a Working Memory Task: Role of Spiking Rate and Spiking History Predicted Discharge

Science.gov (United States)

Devilbiss, David M.; Jenison, Rick L.; Berridge, Craig W.

2012-01-01

Stress, pervasive in society, contributes to over half of all work place accidents a year and over time can contribute to a variety of psychiatric disorders including depression, schizophrenia, and post-traumatic stress disorder. Stress impairs higher cognitive processes, dependent on the prefrontal cortex (PFC) and that involve maintenance and integration of information over extended periods, including working memory and attention. Substantial evidence has demonstrated a relationship between patterns of PFC neuron spiking activity (action-potential discharge) and components of delayed-response tasks used to probe PFC-dependent cognitive function in rats and monkeys. During delay periods of these tasks, persistent spiking activity is posited to be essential for the maintenance of information for working memory and attention. However, the degree to which stress-induced impairment in PFC-dependent cognition involves changes in task-related spiking rates or the ability for PFC neurons to retain information over time remains unknown. In the current study, spiking activity was recorded from the medial PFC of rats performing a delayed-response task of working memory during acute noise stress (93 db). Spike history-predicted discharge (SHPD) for PFC neurons was quantified as a measure of the degree to which ongoing neuronal discharge can be predicted by past spiking activity and reflects the degree to which past information is retained by these neurons over time. We found that PFC neuron discharge is predicted by their past spiking patterns for nearly one second. Acute stress impaired SHPD, selectively during delay intervals of the task, and simultaneously impaired task performance. Despite the reduction in delay-related SHPD, stress increased delay-related spiking rates. These findings suggest that neural codes utilizing SHPD within PFC networks likely reflects an additional important neurophysiological mechanism for maintenance of past information over time. Stress
The impact of specific language impairment on working memory children with ADHD combined subtype

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Jonsdottir, S.; Bouma, A.; Sergeant, J.A.; Scherder, E.J.A.

2005-01-01

The objective of this study was to examine the impact of comorbid specific language impairment (SLI) on verbal and spatial working memory in children with DSM-IV combined subtype Attention Deficit Hyperactivity Disorder (ADHD-C). Participants were a clinical sample of 81/2- to 121/2-year-old
Reduced amygdala reactivity and impaired working memory during dissociation in borderline personality disorder.

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Krause-Utz, Annegret; Winter, Dorina; Schriner, Friederike; Chiu, Chui-De; Lis, Stefanie; Spinhoven, Philip; Bohus, Martin; Schmahl, Christian; Elzinga, Bernet M

2017-05-19

Affective hyper-reactivity and impaired cognitive control of emotional material are core features of borderline personality disorder (BPD). A high percentage of individuals with BPD experience stress-related dissociation, including emotional numbing and memory disruptions. So far little is known about how dissociation influences the neural processing of emotional material in the context of a working memory task in BPD. We aimed to investigate whole-brain activity and amygdala functional connectivity (FC) during an Emotional Working Memory Task (EWMT) after dissociation induction in un-medicated BPD patients compared to healthy controls (HC). Using script-driven imagery, dissociation was induced in 17 patients ('BPD_D'), while 12 patients ('BPD_N') and 18 HC were exposed to neutral scripts during fMRI. Afterwards, participants performed the EWMT with neutral vs. negative IAPS pictures vs. no distractors. Main outcome measures were behavioral performance (reaction times, errors) and whole-brain activity during the EWMT. Psychophysiological interaction analysis was used to examine amygdala connectivity during emotional distraction. BPD patients after dissociation induction showed overall WM impairments, a deactivation in bilateral amygdala, and lower activity in left cuneus, lingual gyrus, and posterior cingulate than BPD_N, along with stronger left inferior frontal gyrus activity than HC. Furthermore, reduced amygdala FC with fusiform gyrus and stronger amygdala FC with right middle/superior temporal gyrus and left inferior parietal lobule was observed in BPD_D. Findings suggest that dissociation affects reactivity to emotionally salient material and WM. Altered activity in areas associated with emotion processing, memory, and self-referential processes may contribute to dissociative states in BPD.
Visual working memory capacity and the medial temporal lobe.

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Jeneson, Annette; Wixted, John T; Hopkins, Ramona O; Squire, Larry R

2012-03-07

Patients with medial temporal lobe (MTL) damage are sometimes impaired at remembering visual information across delays as short as a few seconds. Such impairments could reflect either impaired visual working memory capacity or impaired long-term memory (because attention has been diverted or because working memory capacity has been exceeded). Using a standard change-detection task, we asked whether visual working memory capacity is intact or impaired after MTL damage. Five patients with hippocampal lesions and one patient with large MTL lesions saw an array of 1, 2, 3, 4, or 6 colored squares, followed after 3, 4, or 8 s by a second array where one of the colored squares was cued. The task was to decide whether the cued square had the same color as the corresponding square in the first array or a different color. At the 1 s delay typically used to assess working memory capacity, patients performed as well as controls at all array sizes. At the longer delays, patients performed as well as controls at small array sizes, thought to be within the capacity limit, and worse than controls at large array sizes, thought to exceed the capacity limit. The findings suggest that visual working memory capacity in humans is intact after damage to the MTL structures and that damage to these structures impairs performance only when visual working memory is insufficient to support performance.
Similar verbal memory impairments in schizophrenia and healthy aging. Implications for understanding of neural mechanisms.

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Silver, Henry; Bilker, Warren B

2015-03-30

Memory is impaired in schizophrenia patients but it is not clear whether this is specific to the illness and whether different types of memory (verbal and nonverbal) or memories in different cognitive domains (executive, object recognition) are similarly affected. To study relationships between memory impairments and schizophrenia we compared memory functions in 77 schizophrenia patients, 58 elderly healthy individuals and 41 young healthy individuals. Tests included verbal associative and logical memory and memory in executive and object recognition domains. We compared relationships of memory functions to each other and to other cognitive functions including psychomotor speed and verbal and spatial working memory. Compared to the young healthy group, schizophrenia patients and elderly healthy individuals showed similar severe impairment in logical memory and in the ability to learn new associations (NAL), and similar but less severe impairment in spatial working memory and executive and object memory. Verbal working memory was significantly more impaired in schizophrenia patients than in the healthy elderly. Verbal episodic memory impairment in schizophrenia may share common mechanisms with similar impairment in healthy aging. Impairment in verbal working memory in contrast may reflect mechanisms specific to schizophrenia. Study of verbal explicit memory impairment tapped by the NAL index may advance understanding of abnormal hippocampus dependent mechanisms common to schizophrenia and aging. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Exploration of a 'double-jeopardy' hypothesis within working memory profiles for children with specific language impairment.

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Briscoe, J; Rankin, P M

2009-01-01

Children with specific language impairment (SLI) often experience difficulties in the recall and repetition of verbal information. Archibald and Gathercole (2006) suggested that children with SLI are vulnerable across two separate components of a tripartite model of working memory (Baddeley and Hitch 1974). However, the hierarchical relationship between the 'slave' systems (temporary storage) and the central executive components places a particular challenge for interpreting working memory profiles within a tripartite model. This study aimed to examine whether a 'double-jeopardy' assumption is compatible with a hierarchical relationship between the phonological loop and central executive components of the working memory model in children with SLI. If a strong double-jeopardy assumption is valid for children with SLI, it was predicted that raw scores of working memory tests thought to tap phonological loop and central executive components of tripartite working memory would be lower than the scores of children matched for chronological age and those of children matched for language level, according to independent sources of constraint. In contrast, a hierarchical relationship would imply that a weakness in a slave component of working memory (the phonological loop) would also constrain performance on tests tapping a super-ordinate component (central executive). This locus of constraint would predict that scores of children with SLI on working memory tests that tap the central executive would be weaker relative to the scores of chronological age-matched controls only. Seven subtests of the Working Memory Test Battery for Children (Digit recall, Word recall, Non-word recall, Word matching, Listening recall, Backwards digit recall and Block recall; Pickering and Gathercole 2001) were administered to 14 children with SLI recruited via language resource bases and specialist schools, as well as two control groups matched on chronological age and vocabulary level
Load-sensitive impairment of working memory for biological motion in schizophrenia.

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Lee, Hannah; Kim, Jejoong

2017-01-01

Impaired working memory (WM) is a core cognitive deficit in schizophrenia. Nevertheless, past studies have reported that patients may also benefit from increasing salience of memory stimuli. Such efficient encoding largely depends upon precise perception. Thus an investigation on the relationship between perceptual processing and WM would be worthwhile. Here, we used biological motion (BM), a socially relevant stimulus that schizophrenics have difficulty discriminating from similar meaningless motions, in a delayed-response task. Non-BM stimuli and static polygons were also used for comparison. In each trial, one of the three types of stimuli was presented followed by two probes, with a short delay in between. Participants were asked to indicate whether one of them was identical to the memory item or both were novel. The number of memory items was one or two. Healthy controls were more accurate in recognizing BM than non-BM regardless of memory loads. Patients with schizophrenia exhibited similar accuracy patterns to those of controls in the Load 1 condition only. These results suggest that information contained in BM could facilitate WM encoding in general, but the effect is vulnerable to the increase of cognitive load in schizophrenia, implying inefficient encoding driven by imprecise perception.
Assessing Working Memory in Mild Cognitive Impairment with Serial Order Recall.

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Emrani, Sheina; Libon, David J; Lamar, Melissa; Price, Catherine C; Jefferson, Angela L; Gifford, Katherine A; Hohman, Timothy J; Nation, Daniel A; Delano-Wood, Lisa; Jak, Amy; Bangen, Katherine J; Bondi, Mark W; Brickman, Adam M; Manly, Jennifer; Swenson, Rodney; Au, Rhoda

2018-01-01

Working memory (WM) is often assessed with serial order tests such as repeating digits backward. In prior dementia research using the Backward Digit Span Test (BDT), only aggregate test performance was examined. The current research tallied primacy/recency effects, out-of-sequence transposition errors, perseverations, and omissions to assess WM deficits in patients with mild cognitive impairment (MCI). Memory clinic patients (n = 66) were classified into three groups: single domain amnestic MCI (aMCI), combined mixed domain/dysexecutive MCI (mixed/dys MCI), and non-MCI where patients did not meet criteria for MCI. Serial order/WM ability was assessed by asking participants to repeat 7 trials of five digits backwards. Serial order position accuracy, transposition errors, perseverations, and omission errors were tallied. A 3 (group)×5 (serial position) repeated measures ANOVA yielded a significant group×trial interaction. Follow-up analyses found attenuation of the recency effect for mixed/dys MCI patients. Mixed/dys MCI patients scored lower than non-MCI patients for serial position 3 (p Mixed/dys MCI patients also produced more transposition errors than both groups (p order parameters obtained from the BDT may provide a useful operational definition as well as additional diagnostic information regarding working memory deficits in MCI.
KCNQ channels regulate age-related memory impairment.

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Sonia Cavaliere

Full Text Available In humans KCNQ2/3 heteromeric channels form an M-current that acts as a brake on neuronal excitability, with mutations causing a form of epilepsy. The M-current has been shown to be a key regulator of neuronal plasticity underlying associative memory and ethanol response in mammals. Previous work has shown that many of the molecules and plasticity mechanisms underlying changes in alcohol behaviour and addiction are shared with those of memory. We show that the single KCNQ channel in Drosophila (dKCNQ when mutated show decrements in associative short- and long-term memory, with KCNQ function in the mushroom body α/βneurons being required for short-term memory. Ethanol disrupts memory in wildtype flies, but not in a KCNQ null mutant background suggesting KCNQ maybe a direct target of ethanol, the blockade of which interferes with the plasticity machinery required for memory formation. We show that as in humans, Drosophila display age-related memory impairment with the KCNQ mutant memory defect mimicking the effect of age on memory. Expression of KCNQ normally decreases in aging brains and KCNQ overexpression in the mushroom body neurons of KCNQ mutants restores age-related memory impairment. Therefore KCNQ is a central plasticity molecule that regulates age dependent memory impairment.
Adult ADHD and working memory: neural evidence of impaired encoding.

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Kim, Soyeon; Liu, Zhongxu; Glizer, Daniel; Tannock, Rosemary; Woltering, Steven

2014-08-01

To investigate neural and behavioural correlates of visual encoding during a working memory (WM) task in young adults with and without Attention-Deficit/Hyperactivity Disorder (ADHD). A sample of 30 college students currently meeting a diagnosis of ADHD and 25 typically developing students, matched on age and gender, performed a delayed match-to-sample task with low and high memory load conditions. Dense-array electroencephalography was recorded. Specifically, the P3, an event related potential (ERP) associated with WM, was examined because of its relation with attentional allocation during WM. Task performance (accuracy, reaction time) as well as performance on other neuropsychological tasks of WM was analyzed. Neural differences were found between the groups. Specifically, the P3 amplitude was smaller in the ADHD group compared to the comparison group for both load conditions at parietal-occipital sites. Lower scores on behavioural working memory tasks were suggestive of impaired behavioural WM performance in the ADHD group. Findings from this study provide the first evidence of neural differences in the encoding stage of WM in young adults with ADHD, suggesting ineffective allocation of attentional resources involved in encoding of information in WM. These findings, reflecting alternate neural functioning of WM, may explain some of the difficulties related to WM functioning that college students with ADHD report in their every day cognitive functioning. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
Declarative and Procedural Memory in Danish Speaking Children with Specific Language Impairment

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Lum, Jarrad A. G.; Bleses, Dorthe

2012-01-01

It has been proposed that the language problems in specific language impairment (SLI) arise from basal ganglia abnormalities that lead to impairments with procedural and working memory but not declarative memory. In SLI, this profile of memory functioning has been hypothesized to underlie grammatical impairment but leave lexical knowledge…
High visual working memory capacity in trait social anxiety.

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Moriya, Jun; Sugiura, Yoshinori

2012-01-01

Working memory capacity is one of the most important cognitive functions influencing individual traits, such as attentional control, fluid intelligence, and also psychopathological traits. Previous research suggests that anxiety is associated with impaired cognitive function, and studies have shown low verbal working memory capacity in individuals with high trait anxiety. However, the relationship between trait anxiety and visual working memory capacity is still unclear. Considering that people allocate visual attention more widely to detect danger under threat, visual working memory capacity might be higher in anxious people. In the present study, we show that visual working memory capacity increases as trait social anxiety increases by using a change detection task. When the demand to inhibit distractors increased, however, high visual working memory capacity diminished in individuals with social anxiety, and instead, impaired filtering of distractors was predicted by trait social anxiety. State anxiety was not correlated with visual working memory capacity. These results indicate that socially anxious people could potentially hold a large amount of information in working memory. However, because of an impaired cognitive function, they could not inhibit goal-irrelevant distractors and their performance decreased under highly demanding conditions.
The impact of specific language impairment on working memory in children with ADHD combined type

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Jondottir, S.; Bouma, A.; Sergeant, J.A.; Scherder, E.J.A.

2005-01-01

The objective of this study was to examine the impact of comorbid specific language impairment (SLI) on verbal and spatial working memory in children with DSM-IV combined subtype Attention Deficit Hyperactivity Disorder (ADHD-C). Participants were a clinical sample of 81/2- to 121/2-year-old
Developmental dyscalculia is related to visuo-spatial memory and inhibition impairment.

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Szucs, Denes; Devine, Amy; Soltesz, Fruzsina; Nobes, Alison; Gabriel, Florence

2013-01-01

Developmental dyscalculia is thought to be a specific impairment of mathematics ability. Currently dominant cognitive neuroscience theories of developmental dyscalculia suggest that it originates from the impairment of the magnitude representation of the human brain, residing in the intraparietal sulcus, or from impaired connections between number symbols and the magnitude representation. However, behavioral research offers several alternative theories for developmental dyscalculia and neuro-imaging also suggests that impairments in developmental dyscalculia may be linked to disruptions of other functions of the intraparietal sulcus than the magnitude representation. Strikingly, the magnitude representation theory has never been explicitly contrasted with a range of alternatives in a systematic fashion. Here we have filled this gap by directly contrasting five alternative theories (magnitude representation, working memory, inhibition, attention and spatial processing) of developmental dyscalculia in 9-10-year-old primary school children. Participants were selected from a pool of 1004 children and took part in 16 tests and nine experiments. The dominant features of developmental dyscalculia are visuo-spatial working memory, visuo-spatial short-term memory and inhibitory function (interference suppression) impairment. We hypothesize that inhibition impairment is related to the disruption of central executive memory function. Potential problems of visuo-spatial processing and attentional function in developmental dyscalculia probably depend on short-term memory/working memory and inhibition impairments. The magnitude representation theory of developmental dyscalculia was not supported. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.
Effect of episodic and working memory impairments on semantic and cognitive procedural learning at alcohol treatment entry.

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Pitel, Anne Lise; Witkowski, Thomas; Vabret, François; Guillery-Girard, Bérengère; Desgranges, Béatrice; Eustache, Francis; Beaunieux, Hélène

2007-02-01

Chronic alcoholism is known to impair the functioning of episodic and working memory, which may consequently reduce the ability to learn complex novel information. Nevertheless, semantic and cognitive procedural learning have not been properly explored at alcohol treatment entry, despite its potential clinical relevance. The goal of the present study was therefore to determine whether alcoholic patients, immediately after the weaning phase, are cognitively able to acquire complex new knowledge, given their episodic and working memory deficits. Twenty alcoholic inpatients with episodic memory and working memory deficits at alcohol treatment entry and a control group of 20 healthy subjects underwent a protocol of semantic acquisition and cognitive procedural learning. The semantic learning task consisted of the acquisition of 10 novel concepts, while subjects were administered the Tower of Toronto task to measure cognitive procedural learning. Analyses showed that although alcoholic subjects were able to acquire the category and features of the semantic concepts, albeit slowly, they presented impaired label learning. In the control group, executive functions and episodic memory predicted semantic learning in the first and second halves of the protocol, respectively. In addition to the cognitive processes involved in the learning strategies invoked by controls, alcoholic subjects seem to attempt to compensate for their impaired cognitive functions, invoking capacities of short-term passive storage. Regarding cognitive procedural learning, although the patients eventually achieved the same results as the controls, they failed to automate the procedure. Contrary to the control group, the alcoholic groups' learning performance was predicted by controlled cognitive functions throughout the protocol. At alcohol treatment entry, alcoholic patients with neuropsychological deficits have difficulty acquiring novel semantic and cognitive procedural knowledge. Compared with

Memory rehabilitation for the working memory of patients with multiple sclerosis (MS).

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Mousavi, Shokoufeh; Zare, Hossein; Etemadifar, Masoud; Taher Neshatdoost, Hamid

2018-05-01

The main cognitive impairments in multiple sclerosis (MS) affect the working memory, processing speed, and performances that are in close interaction with one another. Cognitive problems in MS are influenced to a lesser degree by disease recovery medications or treatments,but cognitive rehabilitation is considered one of the promising methods for cure. There is evidence regarding the effectiveness of cognitive rehabilitation for MS patients in various stages of the disease. Since the impairment in working memory is one of the main MS deficits, a particular training that affects this cognitive domain can be of a great value. This study aims to determine the effectiveness of memory rehabilitation on the working memory performance of MS patients. Sixty MS patients with cognitive impairment and similar in terms of demographic characteristics, duration of disease, neurological problems, and mental health were randomly assigned to three groups: namely, experimental, placebo, and control. Patients' cognitive evaluation incorporated baseline assessments immediately post-intervention and 5 weeks post-intervention. The experimental group received a cognitive rehabilitation program in one-hour sessions on a weekly basis for 8 weeks. The placebo group received relaxation techniques on a weekly basis; the control group received no intervention. The results of this study showed that the cognitive rehabilitation program had a positive effect on the working memory performance of patients with MS in the experimental group. These results were achieved in immediate evaluation (post-test) and follow-up 5 weeks after intervention. There was no significant difference in working memory performance between the placebo group and the control group. According to the study, there is evidence for the effectiveness of a memory rehabilitation program for the working memory of patients with MS. Cognitive rehabilitation can improve working memory disorders and have a positive effect on the
Forgetting what you have checked: a link between working memory impairment and checking behaviors in obsessive-compulsive disorder.

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Jaafari, N; Frasca, M; Rigalleau, F; Rachid, F; Gil, R; Olié, J-P; Guehl, D; Burbaud, P; Aouizerate, B; Rotgé, J-Y; Vibert, N

2013-02-01

Compulsive checking behaviors are common in obsessive-compulsive disorder (OCD). Several authors have suggested that these checking rituals could be related to memory deficits. Our aim was to test whether patients with OCD show working memory impairment in relation to their checking behavior. We evaluated the verbal and visuospatial components of patients' and controls' working memory using the reading span and backward location span tests. Checking behaviors were measured by recording participants' eye movements during an image comparison task using a non-invasive, infra-red TOBII 1750 eyetracker. Participants were seated, head-free, in a natural position in front of the eyetracker screen where the images were displayed. Patients with OCD made more gaze moves to compare images than controls. Both patients' working memory spans were reduced, and the patients' deficit in the comparison task was negatively related to their working memory spans. This work demonstrates that checking behavior in OCD is linked to a general reduction of the patients' verbal and visuospatial working memory span. Copyright © 2011 Elsevier Masson SAS. All rights reserved.
The impact of specific language impairment on working memory in children with ADHD combined subtype

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Jonsdottir, S; Bouma, A; Sergeant, JA; Scherder, EJA

The objective of this study was to examine the impact of comorbid specific language impairment (SLI) on verbal and spatial working memory in children with DSM-IV combined subtype Attention Deficit Hyperactivity Disorder (ADHD-C). Participants were a clinical sample of 8 1/2- to 12 1/2-year-old
Impaired long-term memory retention and working memory in sdy mutant mice with a deletion in Dtnbp1, a susceptibility gene for schizophrenia

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Takao Keizo

2008-10-01

Full Text Available Abstract Background Schizophrenia is a complex genetic disorder caused by multiple genetic and environmental factors. The dystrobrevin-binding protein 1 (DTNBP1: dysbindin-1 gene is a major susceptibility gene for schizophrenia. Genetic variations in DTNBP1 are associated with cognitive functions, general cognitive ability and memory function, and clinical features of patients with schizophrenia including negative symptoms and cognitive decline. Since reduced expression of dysbindin-1 has been observed in postmortem brains of patients with schizophrenia, the sandy (sdy mouse, which has a deletion in the Dtnbp1 gene and expresses no dysbindin-1 protein, could be an animal model of schizophrenia. To address this issue, we have carried out a comprehensive behavioral analysis of the sdy mouse in this study. Results In a rotarod test, sdy mice did not exhibit motor learning whilst the wild type mice did. In a Barnes circular maze test both sdy mice and wild type mice learned to selectively locate the escape hole during the course of the training period and in the probe trial conducted 24 hours after last training. However, sdy mice did not locate the correct hole in the retention probe tests 7 days after the last training trial, whereas wild type mice did, indicating impaired long-term memory retention. A T-maze forced alternation task, a task of working memory, revealed no effect of training in sdy mice despite the obvious effect of training in wild type mice, suggesting a working memory deficit. Conclusion Sdy mouse showed impaired long-term memory retention and working memory. Since genetic variation in DTNBP1 is associated with both schizophrenia and memory function, and memory function is compromised in patients with schizophrenia, the sdy mouse may represent a useful animal model to investigate the mechanisms of memory dysfunction in the disorder.
Working Memory Capacity and Its Relation to Stroop Interference and Facilitation Effects in Individuals with Mild Cognitive Impairment

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Sung, Jee Eun; Kim, Jin Hee; Jeong, Jee Hyang; Kang, Heejin

2012-01-01

Purpose: The purposes of the study were to investigate (a) the task-specific differences in short-term memory (STM) and working memory capacity (WMC) in individuals with mild cognitive impairment (MCI) and normal elderly adults (NEAs), (b) the Stroop interference and facilitation effects, and (c) the relationship of STM and WMC to the Stroop…
The Nature of Individual Differences in Working Memory Capacity: Active Maintenance in Primary Memory and Controlled Search from Secondary Memory

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Unsworth, Nash; Engle, Randall W.

2007-01-01

Studies examining individual differences in working memory capacity have suggested that individuals with low working memory capacities demonstrate impaired performance on a variety of attention and memory tasks compared with individuals with high working memory capacities. This working memory limitation can be conceived of as arising from 2…
The Auditory-Visual Speech Benefit on Working Memory in Older Adults with Hearing Impairment

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Jana B. Frtusova

2016-04-01

Full Text Available This study examined the effect of auditory-visual (AV speech stimuli on working memory in hearing impaired participants (HIP in comparison to age- and education-matched normal elderly controls (NEC. Participants completed a working memory n-back task (0- to 2-back in which sequences of digits were presented in visual-only (i.e., speech-reading, auditory-only (A-only, and AV conditions. Auditory event-related potentials (ERP were collected to assess the relationship between perceptual and working memory processing. The behavioural results showed that both groups were faster in the AV condition in comparison to the unisensory conditions. The ERP data showed perceptual facilitation in the AV condition, in the form of reduced amplitudes and latencies of the auditory N1 and/or P1 components, in the HIP group. Furthermore, a working memory ERP component, the P3, peaked earlier for both groups in the AV condition compared to the A-only condition. In general, the HIP group showed a more robust AV benefit; however, the NECs showed a dose-response relationship between perceptual facilitation and working memory improvement, especially for facilitation of processing speed. Two measures, reaction time and P3 amplitude, suggested that the presence of visual speech cues may have helped the HIP to counteract the demanding auditory processing, to the level that no group differences were evident during the AV modality despite lower performance during the A-only condition. Overall, this study provides support for the theory of an integrated perceptual-cognitive system. The practical significance of these findings is also discussed.
Spearmint Extract Improves Working Memory in Men and Women with Age-Associated Memory Impairment.

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Herrlinger, Kelli A; Nieman, Kristin M; Sanoshy, Kristen D; Fonseca, Brenda A; Lasrado, Joanne A; Schild, Arianne L; Maki, Kevin C; Wesnes, Keith A; Ceddia, Michael A

2018-01-01

The purpose of this study was to investigate the effects of supplementation with a spearmint (Mentha spicata L.) extract, high in polyphenols including rosmarinic acid, on cognitive performance, sleep, and mood in individuals with age-associated memory impairment (AAMI). Subjects with AAMI (N = 90; 67% female; age = 59.4 ± 0.6 years) were randomly assigned (n = 30/group) to consume 900, 600, or 0 mg/day (two capsules, once daily) spearmint extract for 90 days, in this double-blind, placebo-controlled trial. Assessments were completed for cognition (days 0, 45, and 90), sleep (days 0 and 90), and mood (days 0 and 90) by using the Cognitive Drug Research (CDR) System ™ , Leeds Sleep Evaluation Questionnaire (LSEQ), and Profile of Mood States (POMS ™ ), respectively. Quality of working memory and spatial working memory accuracy improved after supplementation with 900 mg/day spearmint extract by 15% (p = 0.0469) and 9% (p = 0.0456), respectively, versus placebo. Subjects consuming 900 mg/day spearmint extract reported improvement in their ability to fall asleep, relative to subjects consuming placebo (p = 0.0046). Overall treatment effects were evident for vigor-activity (p = 0.0399), total mood disturbance (p = 0.0374), and alertness and behavior following wakefulness (p = 0.0415), with trends observed for improvements after spearmint supplementation relative to placebo. These results suggest that the distinct spearmint extract may be a beneficial nutritional intervention for cognitive health in older subjects with AAMI.
Psychosocial stress impairs working memory at high loads: An association with cortisol levels and memory retrieval

NARCIS (Netherlands)

Oei, N.Y.L.; Everaerd, W.T.A.M.; Elzinga, B.M.; van Well, S.; Bermond, B.

2006-01-01

Stress and cortisol are known to impair memory retrieval of well-consolidated declarative material. The effects of cortisol on memory retrieval may in particular be due to glucocorticoid (GC) receptors in the hippocampus and prefrontal cortex (PFC). Therefore, effects of stress and cortisol should
Procedural and Declarative Memory in Children with and without Specific Language Impairment

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Lum, Jarrad A. G.; Gelgic, Celin; Conti-Ramsden, Gina

2010-01-01

Background: Much evidence has accumulated to indicate memory deficits in children with specific language impairment. However, most research has focused on working memory impairments in these children. Less is known about the functioning of other memory systems in this population. Aims: This study examined procedural and declarative memory in young…
Functional MRI Study of Working Memory Impairment in Patients with Symptomatic Carotid Artery Disease

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Shasha Zheng

2014-01-01

Full Text Available The neuropsychological tests in patients with internal carotid artery (ICA demonstrated cognitive deficits associated with frontal lobe dysfunction, but the pathophysiological mechanism of memory impairment is not fully understood. This study evaluated relationship between degree of ICA stenosis and frontal activations induced by working memory (WM task using fMRI. The fMRI data of 21 patients with unilateral ICA stenosis (left/right, 11/10 and 21 controls were analyzed. In comparison with controls, ICA patients demonstrated significant activations in middle frontal gyrus (MFG bilaterally, particularly in left MFG. In right ICA stenosis, there was slightly less MFG activation than that of controls. Importantly, lower MFG activity was associated with higher stenosis of ipsilateral ICA. For left ICA stenosis, weaker activation in left MFG was negatively correlated with degree of stenosis. Similarly, for right ICA stenosis, there was a significant negative correlation between right ICA stenosis and weaker activation of right MFG. Cognitive impairments in ICA stenosis were associated with frontal lobe dysfunctions. Left ICA stenosis had worse WM impairments than right ICA stenosis, which was affected by the degree of stenosis.
Working memory binding and episodic memory formation in aging, mild cognitive impairment, and Alzheimer's dementia.

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van Geldorp, Bonnie; Heringa, Sophie M; van den Berg, Esther; Olde Rikkert, Marcel G M; Biessels, Geert Jan; Kessels, Roy P C

2015-01-01

Recent studies indicate that in both normal and pathological aging working memory (WM) performance deteriorates, especially when associations have to be maintained. However, most studies typically do not assess the relationship between WM and episodic memory formation. In the present study, we examined WM and episodic memory formation in normal aging and in patients with early Alzheimer's disease (mild cognitive impairment, MCI; and Alzheimer's dementia, AD). In the first study, 26 young adults (mean age 29.6 years) were compared to 18 middle-aged adults (mean age 52.2 years) and 25 older adults (mean age 72.8 years). We used an associative delayed-match-to-sample WM task, which requires participants to maintain two pairs of faces and houses presented on a computer screen for short (3 s) or long (6 s) maintenance intervals. After the WM task, an unexpected subsequent associative memory task was administered (two-alternative forced choice). In the second study, 27 patients with AD and 19 patients with MCI were compared to 25 older controls, using the same paradigm as that in Experiment 1. Older adults performed worse than both middle-aged and young adults. No effect of delay was observed in the healthy adults, and pairs that were processed during long maintenance intervals were not better remembered in the subsequent memory task. In the MCI and AD patients, longer maintenance intervals hampered the task performance. Also, both patient groups performed significantly worse than controls on the episodic memory task as well as the associative WM task. Aging and AD present with a decline in WM binding, a finding that extends similar results in episodic memory. Longer delays in the WM task did not affect episodic memory formation. We conclude that WM deficits are found when WM capacity is exceeded, which may occur during associative processing.
Cognitive Correlates of Perseverations in Individuals with Memory Impairment.

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Kavé, Gitit; Heinik, Jeremia

2017-02-01

This study examines which cognitive measure best accounts for perseverations in individuals with memory impairment. The sample included 85 individuals, of whom 21 had subjective memory concerns, 27 had mild cognitive impairment, and 37 had Alzheimer's disease. Participants produced responses on a semantic category fluency task and on the ideational fluency (IF) task from the Cambridge Cognitive Examination-Revised. Measures of word finding, working memory, and abstract thinking were also assessed. Significant group differences in percentage of perseverations emerged on both tasks. No cognitive measure accounted for the percentage of perseverations on the semantic fluency task. A measure of abstract thinking was the best predictor of the percentage of perseverations on the IF task, followed by a measure of working memory. The underlying cognitive mechanisms that lead to perseverations differ across tasks, with perseverations on the IF task reflecting both conceptual deficits and working memory limitations. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Impaired Processing of Serial Order Determines Working Memory Impairments in Alzheimer's Disease.

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De Belder, Maya; Santens, Patrick; Sieben, Anne; Fias, Wim

2017-01-01

Working memory (WM) problems are commonly observed in Alzheimer's disease (AD), but the affected mechanisms leading to impaired WM are still insufficiently understood. The ability to efficiently process serial order in WM has been demonstrated to be fundamental to fluent daily life functioning. The decreased capability to mentally process serial position in WM has been put forward as the underlying explanation for generally compromised WM performance. Determine which mechanisms, such as order processing, are responsible for deficient WM functioning in AD. A group of AD patients (n = 32) and their partners (n = 25), assigned to the control group, were submitted to an extensive battery of neuropsychological and experimental tasks, assessing general cognitive state and functioning of several aspects related to serial order WM. The results revealed an impaired ability to bind item information to serial position within WM in AD patients compared to controls. It was additionally observed that AD patients experienced specific difficulties with directing spatial attention when searching for item information stored in WM. The processing of serial order and the allocation of attentional resources are both disrupted, explaining the generally reduced WM functioning in AD patients. Further studies should now clarify whether this observation could explain disease-related problems for other cognitive functions such as verbal expression, auditory comprehension, or planning.
Exploration of a "Double-Jeopardy" Hypothesis within Working Memory Profiles for Children with Specific Language Impairment

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Briscoe, J.; Rankin, P. M.

2009-01-01

Background: Children with specific language impairment (SLI) often experience difficulties in the recall and repetition of verbal information. Archibald and Gathercole (2006) suggested that children with SLI are vulnerable across two separate components of a tripartite model of working memory (Baddeley and Hitch 1974). However, the hierarchical…
Chronic Underactivity of Medial Frontal Cortical β2-Containing Nicotinic Receptors Increases Clozapine-Induced Working Memory Impairment in Female Rats

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Levin, Edward D.; Perkins, Abigail; Brotherton, Terrell; Qazi, Melissa; Berez, Chantal; Montalvo-Ortiz, Janitza; Davis, Kasey; Williams, Paul; Christopher, N. Channelle

2009-01-01

Nicotinic receptor decreases in the frontal cortex and hippocampus are important mediators of cognitive impairment in both schizophrenia and Alzheimer's disease. Drug treatments for these diseases should take into account the impacts of compromised brain function on drug response. This study investigated the impact of compromised nicotinic receptor activity in the frontal cortex in rats on memory function. Since both Alzheimer's disease and schizophrenia can involve psychosis, antipsychotic drugs are often given. The impacts of antipsychotic drugs on cognitive function have been found to be quite variable. It is the hypothesis of this and previous studies that the cognitive effects of antispychotic drugs on cognitive function depend on the integrity of brain systems involved in cognition. Previously in studies of the hippocampus, we found that chronic inhibition of β2-containing nicotinic receptors with dihydro-β-erythrodine (DHβE) impaired working memory and that this effect was attenuated by the antipsychotic drug clozapine. In contrast, chronic hippocampal α7 nicotinic receptor blockade with methyllycaconitine (MLA) potentiated the clozapine-induced memory impairment which is seen in rats without compromised nicotinic receptor activity. The current study determined medial frontal cortical α7 and β2-containing nicotinic receptor involvement in memory and the interactions with antipsychotic drug therapy with clozapine. Chronic DHβE and MLA infusion effects and interactions with systemic clozapine were assessed in female rats tested for memory on the radial-arm maze. Antipsychotic drug interactions with chronic systemic nicotine were investigated because nicotinic procognitive treatment has been proposed. The same local infusion DHβE dose that impaired memory with hippocampal infusion did not impair memory when infused in the medial frontal cortex. Frontal DHβE infusion potentiated clozapine-induced memory impairment, whereas previously the memory
Chronic underactivity of medial frontal cortical beta2-containing nicotinic receptors increases clozapine-induced working memory impairment in female rats.

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Levin, Edward D; Perkins, Abigail; Brotherton, Terrell; Qazi, Melissa; Berez, Chantal; Montalvo-Ortiz, Janitza; Davis, Kasey; Williams, Paul; Christopher, N Channelle

2009-03-17

Nicotinic receptor decreases in the frontal cortex and hippocampus are important mediators of cognitive impairment in both schizophrenia and Alzheimer's disease. Drug treatments for these diseases should take into account the impacts of compromised brain function on drug response. This study investigated the impact of compromised nicotinic receptor activity in the frontal cortex in rats on memory function. Since both Alzheimer's disease and schizophrenia can involve psychosis, antipsychotic drugs are often given. The impacts of antipsychotic drugs on cognitive function have been found to be quite variable. It is the hypothesis of this and previous studies that the cognitive effects of antispychotic drugs on cognitive function depend on the integrity of brain systems involved in cognition. Previously in studies of the hippocampus, we found that chronic inhibition of beta2-containing nicotinic receptors with dihydro-beta-erythrodine (DHbetaE) impaired working memory and that this effect was attenuated by the antipsychotic drug clozapine. In contrast, chronic hippocampal alpha7 nicotinic receptor blockade with methyllycaconitine (MLA) potentiated the clozapine-induced memory impairment which is seen in rats without compromised nicotinic receptor activity. The current study determined medial frontal cortical alpha7 and beta2-containing nicotinic receptor involvement in memory and the interactions with antipsychotic drug therapy with clozapine. Chronic DHbetaE and MLA infusion effects and interactions with systemic clozapine were assessed in female rats tested for memory on the radial-arm maze. Antipsychotic drug interactions with chronic systemic nicotine were investigated because nicotinic procognitive treatment has been proposed. The same local infusion DHbetaE dose that impaired memory with hippocampal infusion did not impair memory when infused in the medial frontal cortex. Frontal DHbetaE infusion potentiated clozapine-induced memory impairment, whereas previously
Transcranial Stimulation of the Dorsolateral Prefrontal Cortex Prevents Stress-Induced Working Memory Deficits.

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Bogdanov, Mario; Schwabe, Lars

2016-01-27

Stress is known to impair working memory performance. This disruptive effect of stress on working memory has been linked to a decrease in the activity of the dorsolateral prefrontal cortex (dlPFC). In the present experiment, we tested whether transcranial direct current stimulation (tDCS) of the dlPFC can prevent stress-induced working memory impairments. We tested 120 healthy participants in a 2 d, sham-controlled, double-blind between-subjects design. Participants completed a test of their individual baseline working memory capacity on day 1. On day 2, participants were exposed to either a stressor or a control manipulation before they performed a visuospatial and a verbal working memory task. While participants completed the tasks, anodal, cathodal, or sham tDCS was applied over the right dlPFC. Stress impaired working memory performance in both tasks, albeit to a lesser extent in the verbal compared with the visuospatial working memory task. This stress-induced working memory impairment was prevented by anodal, but not sham or cathodal, stimulation of the dlPFC. Compared with sham or cathodal stimulation, anodal tDCS led to significantly better working memory performance in both tasks after stress. Our findings indicate a causal role of the dlPFC in working memory impairments after acute stress and point to anodal tDCS as a promising tool to reduce cognitive deficits related to working memory in stress-related mental disorders, such as depression, schizophrenia, or post-traumatic stress disorder. Working memory deficits are prominent in stress-related mental disorders, such as depression, schizophrenia, or post-traumatic stress disorder. Similar working memory impairments have been observed in healthy individuals exposed to acute stress. So far, attempts to prevent such stress-induced working memory deficits focused mainly on pharmacological interventions. Here, we tested the idea that transcranial direct current stimulation of the dorsolateral prefrontal
Working memory impairment in probands with schizoaffective disorder and first degree relatives of schizophrenia probands extend beyond deficits predicted by generalized neuropsychological impairment.

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Kristian Hill, S; Buchholz, Alison; Amsbaugh, Hayley; Reilly, James L; Rubin, Leah H; Gold, James M; Keefe, Richard S E; Pearlson, Godfrey D; Keshavan, Matcheri S; Tamminga, Carol A; Sweeney, John A

2015-08-01

Working memory impairment is well established in psychotic disorders. However, the relative magnitude, diagnostic specificity, familiality pattern, and degree of independence from generalized cognitive deficits across psychotic disorders remain unclear. Participants from the Bipolar and Schizophrenia Network on Intermediate Phenotypes (B-SNIP) study included probands with schizophrenia (N=289), psychotic bipolar disorder (N=227), schizoaffective disorder (N=165), their first-degree relatives (N=315, N=259, N=193, respectively), and healthy controls (N=289). All were administered the WMS-III Spatial Span working memory test and the Brief Assessment of Cognition in Schizophrenia (BACS) battery. All proband groups displayed significant deficits for both forward and backward span compared to controls. However, after covarying for generalized cognitive impairments (BACS composite), all proband groups showed a 74% or greater effect size reduction with only schizoaffective probands showing residual backward span deficits compared to controls. Significant familiality was seen in schizophrenia and bipolar pedigrees. In relatives, both forward and backward span deficits were again attenuated after covarying BACS scores and residual backward span deficits were seen in relatives of schizophrenia patients. Overall, both probands and relatives showed a similar pattern of robust working memory deficits that were largely attenuated when controlling for generalized cognitive deficits. Copyright © 2015 Elsevier B.V. All rights reserved.
Memory Impairment in Children with Language Impairment

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Baird, Gillian; Dworzynski, Katharina; Slonims, Vicky; Simonoff, Emily

2010-01-01

Aim: The aim of this study was to assess whether any memory impairment co-occurring with language impairment is global, affecting both verbal and visual domains, or domain specific. Method: Visual and verbal memory, learning, and processing speed were assessed in children aged 6 years to 16 years 11 months (mean 9y 9m, SD 2y 6mo) with current,…

Reduced prefrontal activation during working and long-term memory tasks and impaired patient-reported cognition among cancer survivors postchemotherapy compared with healthy controls.

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Wang, Lei; Apple, Alexandra C; Schroeder, Matthew P; Ryals, Anthony J; Voss, Joel L; Gitelman, Darren; Sweet, Jerry J; Butt, Zeeshan A; Cella, David; Wagner, Lynne I

2016-01-15

Patients who receive adjuvant chemotherapy have reported cognitive impairments that may last for years after the completion of treatment. Working memory-related and long-term memory-related changes in this population are not well understood. The objective of this study was to demonstrate that cancer-related cognitive impairments are associated with the under recruitment of brain regions involved in working and recognition memory compared with controls. Oncology patients (n = 15) who were receiving adjuvant chemotherapy and had evidence of cognitive impairment according to neuropsychological testing and self-report and a group of age-matched, education group-matched, cognitively normal control participants (n = 14) underwent functional magnetic resonance imaging. During functional magnetic resonance imaging, participants performed a nonverbal n-back working memory task and a visual recognition task. On the working memory task, when 1-back and 2-back data were averaged and contrasted with 0-back data, significantly reduced activation was observed in the right dorsolateral prefrontal cortex for oncology patients versus controls. On the recognition task, oncology patients displayed decreased activity of the left-middle hippocampus compared with controls. Neuroimaging results were not associated with patient-reported cognition. Decreased recruitment of brain regions associated with the encoding of working memory and recognition memory was observed in the oncology patients compared with the control group. These results suggest that there is a reduction in neural functioning postchemotherapy and corroborate patient-reported cognitive difficulties after cancer treatment, although a direct association was not observed. Cancer 2016;122:258-268. © 2015 American Cancer Society. © 2015 American Cancer Society.
Impaired inhibition and working memory in response to internet-related words among adolescents with internet addiction: A comparison with attention-deficit/hyperactivity disorder.

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Nie, Jia; Zhang, Wei; Chen, Jia; Li, Wendi

2016-02-28

Impairments in response inhibition and working memory functions have been found to be closely associated with internet addiction (IA) symptoms and attention-deficit/hyperactivity disorder (ADHD) symptoms. In this study, we examined response inhibition and working memory processes with two different materials (internet-related and internet-unrelated stimuli) among adolescents with IA, ADHD and co-morbid IA/ADHD. Twenty-four individuals with IA, 28 individuals with ADHD, 17 individuals with IA/ADHD, and 26 matched normal controls (NC) individuals were recruited. All participants were measured with a Stop-Signal Task and 2-Back Task under the same experimental conditions. In comparison to the NC group, subjects with IA, ADHD and IA/ADHD demonstrated impaired inhibition and working memory. In addition, in comparison to internet-unrelated conditions, IA and co-morbid subjects performed worse on the internet-related condition in the Stop trials during the stop-signal task, and they showed better working memory on the internet-related condition in the 2-Back Task. The findings of our study suggest individuals with IA and IA/ADHD may be impaired in inhibition and working memory functions that might be linked to poor inhibition specifically related to internet-related stimuli, which will advance our understanding of IA and contribute to prevention and intervention strategies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Working memory load impairs the evaluation of behavioral errors in the medial frontal cortex.

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Maier, Martin E; Steinhauser, Marco

2017-10-01

Early error monitoring in the medial frontal cortex enables error detection and the evaluation of error significance, which helps prioritize adaptive control. This ability has been assumed to be independent from central capacity, a limited pool of resources assumed to be involved in cognitive control. The present study investigated whether error evaluation depends on central capacity by measuring the error-related negativity (Ne/ERN) in a flanker paradigm while working memory load was varied on two levels. We used a four-choice flanker paradigm in which participants had to classify targets while ignoring flankers. Errors could be due to responding either to the flankers (flanker errors) or to none of the stimulus elements (nonflanker errors). With low load, the Ne/ERN was larger for flanker errors than for nonflanker errors-an effect that has previously been interpreted as reflecting differential significance of these error types. With high load, no such effect of error type on the Ne/ERN was observable. Our findings suggest that working memory load does not impair the generation of an Ne/ERN per se but rather impairs the evaluation of error significance. They demonstrate that error monitoring is composed of capacity-dependent and capacity-independent mechanisms. © 2017 Society for Psychophysiological Research.
Impaired working memory capacity is not caused by failures of selective attention in schizophrenia.

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Erickson, Molly A; Hahn, Britta; Leonard, Carly J; Robinson, Benjamin; Gray, Brad; Luck, Steven J; Gold, James

2015-03-01

The cognitive impairments associated with schizophrenia have long been known to involve deficits in working memory (WM) capacity. To date, however, the causes of WM capacity deficits remain unknown. The present study examined selective attention impairments as a putative contributor to observed capacity deficits in this population. To test this hypothesis, we used an experimental paradigm that assesses the role of selective attention in WM encoding and has been shown to involve the prefrontal cortex and the basal ganglia. In experiment 1, participants were required to remember the locations of 3 or 5 target items (red circles). In another condition, 3-target items were accompanied by 2 distractor items (yellow circles), which participants were instructed to ignore. People with schizophrenia (PSZ) exhibited significant impairment in memory for the locations of target items, consistent with reduced WM capacity, but PSZ and healthy control subjects did not differ in their ability to filter the distractors. This pattern was replicated in experiment 2 for distractors that were more salient. Taken together, these results demonstrate that reduced WM capacity in PSZ is not attributable to a failure of filtering irrelevant distractors. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Patients with chronic insomnia have selective impairments in memory that are modulated by cortisol.

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Chen, Gui-Hai; Xia, Lan; Wang, Fang; Li, Xue-Wei; Jiao, Chuan-An

2016-10-01

Memory impairment is a frequent complaint in insomniacs; however, it is not consistently demonstrated. It is unknown whether memory impairment in insomniacs involves neuroendocrine dysfunction. The participants in this study were selected from the clinical setting and included 21 patients with chronic insomnia disorder (CID), 25 patients with insomnia and comorbid depressive disorder (CDD), and 20 control participants without insomnia. We evaluated spatial working and reference memory, object working and reference memory, and object recognition memory using the Nine Box Maze Test. We also evaluated serum neuroendocrine hormone levels. Compared to the controls, the CID patients made significantly more errors in spatial working and object recognition memory (p memory types (p memory (r = .534, p = .033) and negatively correlated with the errors in object recognition memory (r = -.659, p = .006) in the CID patients. The results suggest that the CID patients had selective memory impairment, which may be mediated by increased cortisol levels. © 2016 Society for Psychophysiological Research.
Frequency-dependent brain regional homogeneity alterations in patients with mild cognitive impairment during working memory state relative to resting state

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Pengyun eWang

2016-03-01

Full Text Available Several studies have reported working memory deficits in patients with mild cognitive impairment (MCI. However, previous studies investigating the neural mechanisms of MCI have primarily focused on brain activity alterations during working memory tasks. No study to date has compared brain network alterations in the working memory state between MCI patients and normal control subjects. Therefore, using the index of regional homogeneity (ReHo, we explored brain network impairments in MCI patients during a working memory task relative to the resting state, and identified frequency-dependent effects in separate frequency bands.Our results indicate that, in MCI patients, ReHo is altered in the posterior cingulate cortex in the slow-3 band (0.073–0.198 Hz, and in the bottom of the right occipital lobe and part of the right cerebellum, the right thalamus, a diffusing region in the bilateral prefrontal cortex, the left and right parietal-occipital regions, and the right angular gyrus in the slow-5 band (0.01–0.027 Hz. Furthermore, in normal controls, the value of ReHo in clusters belonging to the default mode network decreased, while the value of ReHo in clusters belonging to the attentional network increased during the task state. However, this pattern was reversed in MCI patients, and was associated with decreased working memory performance. In addition, we identified altered functional connectivity of the abovementioned regions with other parts of the brain in MCI patients.This is the first study to compare frequency-dependent alterations of ReHo in MCI patients between resting and working memory states. The results provide a new perspective regarding the neural mechanisms of working memory deficits in MCI patients, and extend our knowledge of altered brain patterns in resting and task-evoked states.
Episodic and working memory deficits in alcoholic Korsakoff patients: the continuity theory revisited.

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Pitel, Anne Lise; Beaunieux, Hélène; Witkowski, Thomas; Vabret, François; de la Sayette, Vincent; Viader, Fausto; Desgranges, Béatrice; Eustache, Francis

2008-07-01

The exact nature of episodic and working memory impairments in alcoholic Korsakoff patients (KS) remains unclear, as does the specificity of these neuropsychological deficits compared with those of non-Korsakoff alcoholics (AL). The goals of the present study were therefore to (1) specify the nature of episodic and working memory impairments in KS, (2) determine the specificity of the KS neuropsychological profile compared with the AL profile, and (3) observe the distribution of individual performances within the 2 patient groups. We investigated episodic memory (encoding and retrieval abilities, contextual memory and state of consciousness associated with memories), the slave systems of working memory (phonological loop, visuospatial sketchpad and episodic buffer) and executive functions (inhibition, flexibility, updating and integration abilities) in 14 strictly selected KS, 40 AL and 55 control subjects (CS). Compared with CS, KS displayed impairments of episodic memory encoding and retrieval, contextual memory, recollection, the slave systems of working memory and executive functions. Although episodic memory was more severely impaired in KS than in AL, the single specificity of the KS profile was a disproportionately large encoding deficit. Apart from organizational and updating abilities, the slave systems of working memory and inhibition, flexibility and integration abilities were impaired to the same extent in both alcoholic groups. However, some KS were unable to complete the most difficult executive tasks. There was only a partial overlap of individual performances by KS and AL for episodic memory and a total mixture of the 2 groups for working memory. Korsakoff's syndrome encompasses impairments of the different episodic and working memory components. AL and KS displayed similar profiles of episodic and working memory deficits, in accordance with neuroimaging investigations showing similar patterns of brain damage in both alcoholic groups.
Do TRPC channels support working memory? Comparing modulations of TRPC channels and working memory through G-protein coupled receptors and neuromodulators.

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Reboreda, Antonio; Theissen, Frederik M; Valero-Aracama, Maria J; Arboit, Alberto; Corbu, Mihaela A; Yoshida, Motoharu

2018-03-01

Working memory is a crucial ability we use in daily life. However, the cellular mechanisms supporting working memory still remain largely unclear. A key component of working memory is persistent neural firing which is believed to serve short-term (hundreds of milliseconds up to tens of seconds) maintenance of necessary information. In this review, we will focus on the role of transient receptor potential canonical (TRPC) channels as a mechanism underlying persistent firing. Many years of in vitro work have been suggesting a crucial role of TRPC channels in working memory and temporal association tasks. If TRPC channels are indeed a central mechanism for working memory, manipulations which impair or facilitate working memory should have a similar effect on TRPC channel modulation. However, modulations of working memory and TRPC channels were never systematically compared, and it remains unanswered whether TRPC channels indeed contribute to working memory in vivo or not. In this article, we review the effects of G-protein coupled receptors (GPCR) and neuromodulators, including acetylcholine, noradrenalin, serotonin and dopamine, on working memory and TRPC channels. Based on comparisons, we argue that GPCR and downstream signaling pathways that activate TRPC, generally support working memory, while those that suppress TRPC channels impair it. However, depending on the channel types, areas, and systems tested, this is not the case in all studies. Further work to clarify involvement of specific TRPC channels in working memory tasks and how they are affected by neuromodulators is still necessary in the future. Copyright © 2018 Elsevier B.V. All rights reserved.
Working memory limitations in children with severe language impairment

NARCIS (Netherlands)

Daal, J.G.H.L. van; Verhoeven, L.T.W.; Leeuwe, J.F.J. van; Balkom, L.J.M. van

2008-01-01

In the present study, the relations of various aspects of working memory to various aspects of language problems in a clinical sample of 97 Dutch speaking 5-year-old children with severe language problems were studied. The working memory and language abilities of the children were examined using an
Developmental Associations between Working Memory and Language in Children with Specific Language Impairment: A Longitudinal Study

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Vugs, Brigitte; Hendriks, Marc; Cuperus, Juliane; Knoors, Harry; Verhoeven, Ludo

2017-01-01

Purpose: This longitudinal study examined differences in the development of working memory (WM) between children with specific language impairment (SLI) and typically developing (TD) children. Further, it explored to what extent language at ages 7-8 years could be predicted by measures of language and/or WM at ages 4-5 years. Method: Thirty…
Aging accelerates memory extinction and impairs memory restoration in Drosophila.

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Chen, Nannan; Guo, Aike; Li, Yan

2015-05-15

Age-related memory impairment (AMI) is a phenomenon observed from invertebrates to human. Memory extinction is proposed to be an active inhibitory modification of memory, however, whether extinction is affected in aging animals remains to be elucidated. Employing a modified paradigm for studying memory extinction in fruit flies, we found that only the stable, but not the labile memory component was suppressed by extinction, thus effectively resulting in higher memory loss in aging flies. Strikingly, young flies were able to fully restore the stable memory component 3 h post extinction, while aging flies failed to do so. In conclusion, our findings reveal that both accelerated extinction and impaired restoration contribute to memory impairment in aging animals. Copyright © 2015 Elsevier Inc. All rights reserved.
Relationships between divided attention and working memory impairment in people with schizophrenia.

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Gray, Bradley E; Hahn, Britta; Robinson, Benjamin; Harvey, Alex; Leonard, Carly J; Luck, Steven J; Gold, James M

2014-11-01

Recent studies suggest that people with schizophrenia (PSZ) have difficulty distributing their attention broadly. Other research suggests that PSZ have reduced working memory (WM) capacity. This study tested whether these findings reflect a common underlying deficit. We measured the ability to distribute attention by means of the Useful Field of View (UFOV) task, in which participants must distribute attention so that they can discriminate a foveal target and simultaneously localize a peripheral target. Participants included 50 PSZ and 52 healthy control subjects. We found that PSZ exhibited severe impairments in UFOV performance, that UFOV performance was highly correlated with WM capacity in PSZ (r = -.61), and that UFOV impairments could not be explained by either impaired low-level processing or a generalized deficit. These results suggest that a common mechanism explains deficits in the ability to distribute attention broadly, reduced WM capacity, and other aspects of impaired cognition in schizophrenia. We hypothesize that this mechanism may involve abnormal local circuit dynamics that cause a hyperfocusing of resources onto a small number of internal representations. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Intrahippocampal Administration of Amyloid-β1–42 Oligomers Acutely Impairs Spatial Working Memory, Insulin Signaling, and Hippocampal Metabolism

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Pearson-Leary, Jiah; McNay, Ewan C.

2017-01-01

Increasing evidence suggests that abnormal brain accumulation of amyloid-β1–42 (Aβ1–42) oligomers plays a causal role in Alzheimer’s disease (AD), and in particular may cause the cognitive deficits that are the hallmark of AD. In vitro, Aβ1–42 oligomers impair insulin signaling and suppress neural functioning. We previously showed that endogenous insulin signaling is an obligatory component of normal hippocampal function, and that disrupting this signaling led to a rapid impairment of spatial working memory, while delivery of exogenous insulin to the hippocampus enhanced both memory and metabolism; diet-induced insulin resistance both impaired spatial memory and prevented insulin from increasing metabolism or cognitive function. Hence, we tested the hypothesis that Aβ1–42 oligomers could acutely impair hippocampal metabolic and cognitive processes in vivo in the rat. Our findings support this hypothesis: Aβ1–42 oligomers impaired spontaneous alternation behavior while preventing the task-associated dip in hippocampal ECF glucose observed in control animals. In addition, Aβ1–42 oligomers decreased plasma membrane translocation of the insulin-sensitive glucose transporter 4 (GluT4), and impaired insulin signaling as measured by phosphorylation of Akt. These data show in vivo that Aβ1–42 oligomers can rapidly impair hippocampal cognitive and metabolic processes, and provide support for the hypothesis that elevated Aβ1–42 leads to cognitive impairment via interference with hippocampal insulin signaling. PMID:22430529
Effects of Ganglioside on Working Memory and the Default Mode Network in Individuals with Subjective Cognitive Impairment: A Randomized Controlled Trial.

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Jeon, Yujin; Kim, Binna; Kim, Jieun E; Kim, Bori R; Ban, Soonhyun; Jeong, Jee Hyang; Kwon, Oran; Rhie, Sandy Jeong; Ahn, Chang-Won; Kim, Jong-Hoon; Jung, Sung Ug; Park, Soo-Hyun; Lyoo, In Kyoon; Yoon, Sujung

2016-01-01

This randomized, double-blind, placebo-controlled trial examined whether the administration of ganglioside, an active ingredient of deer bone extract, can improve working memory performance by increasing gray matter volume and functional connectivity in the default mode network (DMN) in individuals with subjective cognitive impairment. Seventy-five individuals with subjective cognitive impairment were chosen to receive either ganglioside (330[Formula: see text][Formula: see text]g/day or 660[Formula: see text][Formula: see text]g/day) or a placebo for 8 weeks. Changes in working memory performance with treatment of either ganglioside or placebo were assessed as cognitive outcome measures. Using voxel-based morphometry and functional connectivity analyses, changes in gray matter volume and functional connectivity in the DMN were also assessed as brain outcome measures. Improvement in working memory performance was greater in the ganglioside group than in the placebo group. The ganglioside group, relative to the placebo group, showed greater increases in gray matter volume and functional connectivity in the DMN. A significant relationship between increased functional connectivity of the precuneus and improved working memory performance was observed in the ganglioside group. The current findings suggest that ganglioside has cognitive-enhancing effects in individuals with subjective cognitive impairment. Ganglioside-induced increases in gray matter volume and functional connectivity in the DMN may partly be responsible for the potential nootropic effects of ganglioside. The clinical trial was registered with ClinicalTrials.gov (identifier: NCT02379481).
Dual-tasking and gait in people with Mild Cognitive Impairment. The effect of working memory

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Phillips Natalie A

2009-09-01

Full Text Available Abstract Background Cognition and mobility in older adults are closely associated and they decline together with aging. Studies evaluating associations between cognitive factors and gait performance in people with Mild Cognitive Impairment (MCI are scarce. In this study, our aim was to determine whether specific cognitive factors have a more identifiable effect on gait velocity during dual-tasking in people with MCI. Methods Fifty-five participants, mean age 77.7 (SD = 5.9, 45% women, with MCI were evaluated for global cognition, working memory, executive function, and attention. Gait Velocity (GV was measured under a single-task condition (single GV and under two dual-task conditions: 1 while counting backwards (counting GV, 2 while naming animals (verbal GV. Multivariable linear regression analysis was used to examine associations with an alpha-level of 0.05. Results Participants experienced a reduction in GV while engaging in dual-task challenges (p Conclusion In older adults with MCI, low working memory performance was associated with slow GV. Dual-task conditions showed the strongest associations with gait slowing. Our findings suggest that cortical control of gait is associated with decline in working memory in people with MCI.
Interactions between working memory and language in young children with specific language impairment (SLI).

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Vugs, Brigitte; Knoors, Harry; Cuperus, Juliane; Hendriks, Marc; Verhoeven, Ludo

2016-01-01

The underlying structure of working memory (WM) in young children with and without specific language impairment (SLI) was examined. The associations between the components of WM and the language abilities of young children with SLI were then analyzed. The Automated Working Memory Assessment and four linguistic tasks were administered to 58 children with SLI and 58 children without SLI, aged 4-5 years. The WM of the children was best represented by a model with four separate but interacting components of verbal storage, visuospatial storage, verbal central executive (CE), and visuospatial CE. The associations between the four components of WM did not differ significantly for the two groups of children. However, the individual components of WM showed varying associations with the language abilities of the children with SLI. The verbal CE component of WM was moderately to strongly associated with all the language abilities in children with SLI: receptive vocabulary, expressive vocabulary, verbal comprehension, and syntactic development. These results show verbal CE to be involved in a wide range of linguistic skills; the limited ability of young children with SLI to simultaneously store and process verbal information may constrain their acquisition of linguistic skills. Attention should thus be paid to the language problems of children with SLI, but also to the WM impairments that can contribute to their language problems.
Impaired short-term memory for pitch in congenital amusia.

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Tillmann, Barbara; Lévêque, Yohana; Fornoni, Lesly; Albouy, Philippe; Caclin, Anne

2016-06-01

Congenital amusia is a neuro-developmental disorder of music perception and production. The hypothesis is that the musical deficits arise from altered pitch processing, with impairments in pitch discrimination (i.e., pitch change detection, pitch direction discrimination and identification) and short-term memory. The present review article focuses on the deficit of short-term memory for pitch. Overall, the data discussed here suggest impairments at each level of processing in short-term memory tasks; starting with the encoding of the pitch information and the creation of the adequate memory trace, the retention of the pitch traces over time as well as the recollection and comparison of the stored information with newly incoming information. These impairments have been related to altered brain responses in a distributed fronto-temporal network, associated with decreased connectivity between these structures, as well as in abnormalities in the connectivity between the two auditory cortices. In contrast, amusic participants׳ short-term memory abilities for verbal material are preserved. These findings show that short-term memory deficits in congenital amusia are specific to pitch, suggesting a pitch-memory system that is, at least partly, separated from verbal memory. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2015 Elsevier B.V. All rights reserved.
Andrographolide - A promising therapeutic agent, negatively regulates glial cell derived neurodegeneration of prefrontal cortex, hippocampus and working memory impairment.

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Das, Sudeshna; Mishra, K P; Ganju, Lilly; Singh, S B

2017-12-15

Over activation of glial cell derived innate immune factors induces neuro-inflammation that results in neurodegenerative disease, like working memory impairment. In this study, we have investigated the role of andrographolide, a major constituent of Andrographis paniculata plant, in reduction of reactive glial cell derived working memory impairment. Real time PCR, Western bloting, flow cytometric and immunofluorescence studies demonstrated that andrographolide inhibited lipopolysaccharide (LPS)-induced overexpression of HMGB1, TLR4, NFκB, COX-2, iNOS, and release of inflammatory mediators in primary mix glial culture, adult mice prefrontal cortex and hippocampus region. Active microglial and reactive astrocytic makers were also downregulated after andrographolide treatment. Andrographolide suppressed overexpression of microglial MIP-1α, P2X7 receptor and its downstream signaling mediators including-inflammasome NLRP3, caspase1 and mature IL-1β. Furthermore, in vivo maze studies suggested that andrographolide treatment reversed LPS-induced behavioural and working memory disturbances including regulation of expression of protein markers like PKC, p-CREB, amyloid beta, APP, p-tau, synapsin and PSD-95. Andrographolide, by lowering expression of pro apoptotic genes and enhancing the expression of anti-apoptotic gene showed its anti-apoptotic nature that in turn reduces neurodegeneration. Morphology studies using Nissl and FJB staining also showed the neuroprotective effect of andrographolide in the prefrontal cortex region. The above studies indicated that andrographolide prevented neuroinflammation-associated neurodegeneration and improved synaptic plasticity markers in cortical as well as hippocampal region which suggests that andrographolide could be a novel pharmacological countermeasure for the treatment of neuroinflammation and neurological disorders related to memory impairment. Copyright © 2017 Elsevier B.V. All rights reserved.
Multimodal MRI reveals structural connectivity differences in 22q11 deletion syndrome related to impaired spatial working memory

NARCIS (Netherlands)

O'Hanlon, Erik; Howley, Sarah; Prasad, Sarah; McGrath, Jane; Leemans, Alexander; McDonald, Colm; Garavan, Hugh; Murphy, Kieran C

2016-01-01

INTRODUCTION: Impaired spatial working memory is a core cognitive deficit observed in people with 22q11 Deletion syndrome (22q11DS) and has been suggested as a candidate endophenotype for schizophrenia. However, to date, the neuroanatomical mechanisms describing its structural and functional
The relationship among unawareness of memory impairment, depression, and dementia in older adults with memory impairment in Singapore.

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Liu, Jianlin; Abdin, Edimansyah; Vaingankar, Janhavi A; Shafie, Saleha B; Jeyagurunathan, Anitha; Shahwan, Shazana; Magadi, Harish; Ng, Li Ling; Chong, Siow Ann; Subramaniam, Mythily

2017-11-01

Previous research has studied the relationships among unawareness of memory impairment, depression, and dementia in older adults with severe dementia, but it has not considered the associations and clinical implications at earlier stages of memory impairment. This study therefore sought to examine the relationship among unawareness of memory impairment, depression, and dementia in older adults with memory impairment in Singapore. The participants were 751 older adults with memory impairment in Singapore. They were assessed for objective and subjective memory loss, depression, and dementia severity. Participants' subjective memory loss was determined based on a self-appraisal question on memory, and their objective memory loss was calculated based on their performance on three cognitive tasks. Unawareness was assessed based on the contrast between subjective and objective memory loss. Descriptive statistics revealed a high prevalence of unawareness (80.4%). Logistic regression analysis revealed that gender and marital status were significantly associated with unawareness. Men (odds ratio (OR) = 2.5) and those who were divorced or separated (OR = 23.0) were more likely to be unaware than women and those who were married, respectively. After chronic conditions and demographic characteristics were controlled for, multivariate logistic regression analyses revealed that older adults with depression were less likely (OR = 0.2) to be unaware than those without depression. Unawareness was also related with dementia severity; older adults with questionable (OR = 0.3) and mild dementia (OR = 0.4) were less likely to be unaware than someone without dementia. Unawareness of memory impairment was common among older adults with memory impairment. However, unawareness may be the result of denial as a strategy for coping with memory loss of which the older adult is aware. Psychological care should be integrated into the overall treatment management of dementia to

Age-related decline in verbal learning is moderated by demographic factors, working memory capacity, and presence of amnestic mild cognitive impairment.

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Constantinidou, Fofi; Zaganas, Ioannis; Papastefanakis, Emmanouil; Kasselimis, Dimitrios; Nidos, Andreas; Simos, Panagiotis G

2014-09-01

Age-related memory changes are highly varied and heterogeneous. The study examined the rate of decline in verbal episodic memory as a function of education level, auditory attention span and verbal working memory capacity, and diagnosis of amnestic mild cognitive impairment (a-MCI). Data were available on a community sample of 653 adults aged 17-86 years and 70 patients with a-MCI recruited from eight broad geographic areas in Greece and Cyprus. Measures of auditory attention span and working memory capacity (digits forward and backward) and verbal episodic memory (Auditory Verbal Learning Test [AVLT]) were used. Moderated mediation regressions on data from the community sample did not reveal significant effects of education level on the rate of age-related decline in AVLT indices. The presence of a-MCI was a significant moderator of the direct effect of Age on both immediate and delayed episodic memory indices. The rate of age-related decline in verbal episodic memory is normally mediated by working memory capacity. Moreover, in persons who display poor episodic memory capacity (a-MCI group), age-related memory decline is expected to advance more rapidly for those who also display relatively poor verbal working memory capacity.
Negative affect impairs associative memory but not item memory.

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Bisby, James A; Burgess, Neil

2013-12-17

The formation of associations between items and their context has been proposed to rely on mechanisms distinct from those supporting memory for a single item. Although emotional experiences can profoundly affect memory, our understanding of how it interacts with different aspects of memory remains unclear. We performed three experiments to examine the effects of emotion on memory for items and their associations. By presenting neutral and negative items with background contexts, Experiment 1 demonstrated that item memory was facilitated by emotional affect, whereas memory for an associated context was reduced. In Experiment 2, arousal was manipulated independently of the memoranda, by a threat of shock, whereby encoding trials occurred under conditions of threat or safety. Memory for context was equally impaired by the presence of negative affect, whether induced by threat of shock or a negative item, relative to retrieval of the context of a neutral item in safety. In Experiment 3, participants were presented with neutral and negative items as paired associates, including all combinations of neutral and negative items. The results showed both above effects: compared to a neutral item, memory for the associate of a negative item (a second item here, context in Experiments 1 and 2) is impaired, whereas retrieval of the item itself is enhanced. Our findings suggest that negative affect impairs associative memory while recognition of a negative item is enhanced. They support dual-processing models in which negative affect or stress impairs hippocampal-dependent associative memory while the storage of negative sensory/perceptual representations is spared or even strengthened.
Impaired visual, working, and verbal memory in first-episode, drug-naive patients with major depressive disorder in a Chinese population.

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Chen, Ce; Jiang, Wen-Hui; Wang, Wei; Ma, Xian-Cang; Li, Ye; Wu, Jin; Hashimoto, Kenji; Gao, Cheng-Ge

2018-01-01

Cognitive impairment has been observed in patients with major depressive disorder (MDD). However, it remains unclear whether the deficits in specific cognitive domains are present in first-episode, drug-naïve patients or medicated patients. In the present study, using the CogState battery (CSB) Chinese language version, we evaluated the visual, working, and verbal memory in first-episode drug-naive patients and medicated patients with MDD in a Chinese population. We measured the cognitive function in first-episode drug-naïve patients (n = 36), medicated MDD patients (n = 71), and age- and sex-matched healthy control subjects (n = 59) in a Chinese population. The CSB composite scores in both first-episode drug-naive patients and medicated patients were significantly poorer than those in the healthy control subjects. The CSB sub-scores, including visual, working, and verbal memory were also significantly poorer in both patient groups than those in the healthy control subjects. In contrast, processing speed, attention/vigilance, executive function, spatial working memory, and social cognition were no different from healthy controls, whereas the executive function was significantly better in the medicated patients than in the healthy control subjects and first-episode drug-naïve patients. These findings suggest an impairment in the visual, working, and verbal memory in first-episode, drug-naive MDD patients in a Chinese population.
Predictors of verbal working memory in children with cerebral palsy.

NARCIS (Netherlands)

Peeters, M.; Verhoeven, L.; Moor, J.M.H. de

2009-01-01

The goal of the present study was to examine the precursors of verbal working memory in 52 children with cerebral palsy with varying degrees of speech impairments in the first grade of special education. Following Baddeley's model of working memory, children's verbal working memory was measured by
Predictors of verbal working memory in children with cerebral palsy

NARCIS (Netherlands)

Peeters, M.H.J.; Verhoeven, L.T.W.; Moor, J.M.H. de

2009-01-01

The goal of the present study was to examine the precursors of verbal working memory in 52 children with cerebral palsy with varying degrees of speech impairments in the first grade of special education. Following Baddeley's model of working memory, children's verbal working memory was measured by
The impact of specific language impairment on working memory children with ADHD combined subtype

OpenAIRE

Jonsdottir, S.; Bouma, A.; Sergeant, J.A.; Scherder, E.J.A.

2005-01-01

The objective of this study was to examine the impact of comorbid specific language impairment (SLI) on verbal and spatial working memory in children with DSM-IV combined subtype Attention Deficit Hyperactivity Disorder (ADHD-C). Participants were a clinical sample of 81/2- to 121/2-year-old children diagnosed with ADHD-C. A group of ADHD-C with SLI was compared to a group of ADHD-C without SLI, and a group of normal children, matched on age and nonverbal intelligence. The results show that A...
Cancer 'survivor-care': II. Disruption of prefrontal brain activation top-down control of working memory capacity as possible mechanism for chemo-fog/brain (chemotherapy-associated cognitive impairment).

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Raffa, R B

2013-08-01

Cancer chemotherapy-associated cognitive impairments (termed 'chemo-fog' or 'chemo-brain'), particularly in memory, have been self-reported or identified in cancer survivors previously treated with chemotherapy. Although a variety of deficits have been detected, a consistent theme is a detriment in visuospatial working memory. The parietal cortex, a major site of storage of such memory, is implicated in chemotherapy-induced damage. However, if the findings of two recent publications are combined, the (pre)frontal cortex might be an equally viable target. Two recent studies, one postulating a mechanism for 'top-down control' of working memory capacity and another visualizing chemotherapy-induced alterations in brain activation during working memory processing, are reviewed and integrated. A computational model and the proposal that the prefrontal cortex plays a role in working memory via top-down control of parietal working memory capacity is consistent with a recent demonstration of decreased frontal hyperactivation following chemotherapy. Chemotherapy-associated impairment of visuospatial working memory might include the (pre)frontal cortex in addition to the parietal cortex. This provides new opportunity for basic science and clinical investigation. © 2013 John Wiley & Sons Ltd.
A model of memory impairment in schizophrenia: cognitive and clinical factors associated with memory efficiency and memory errors.

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Brébion, Gildas; Bressan, Rodrigo A; Ohlsen, Ruth I; David, Anthony S

2013-12-01

Memory impairments in patients with schizophrenia have been associated with various cognitive and clinical factors. Hallucinations have been more specifically associated with errors stemming from source monitoring failure. We conducted a broad investigation of verbal memory and visual memory as well as source memory functioning in a sample of patients with schizophrenia. Various memory measures were tallied, and we studied their associations with processing speed, working memory span, and positive, negative, and depressive symptoms. Superficial and deep memory processes were differentially associated with processing speed, working memory span, avolition, depression, and attention disorders. Auditory/verbal and visual hallucinations were differentially associated with specific types of source memory error. We integrated all the results into a revised version of a previously published model of memory functioning in schizophrenia. The model describes the factors that affect memory efficiency, as well as the cognitive underpinnings of hallucinations within the source monitoring framework. © 2013.
Dieting and Food Cue-Related Working Memory Performance

OpenAIRE

Meule, Adrian

2016-01-01

Executive functioning (e.g., working memory) is tightly intertwined with self-regulation. For example, food cue-elicited craving has been found to impair working memory performance. Furthermore, current dieters have been found to show lower working memory performance than non-dieters. Recent research, however, suggests that it is crucial to consider dieting success in addition to current dieting status or restrained eating in order to reveal cognitive mechanisms that are associated with succe...
Comparison of visual working memory in deaf and hearing-impaired students with normal counterparts: A research in people without sign language

Directory of Open Access Journals (Sweden)

Farideh Tangestani Zadeh

2015-02-01

Full Text Available Background and Aim: The hearing defects in deaf and hearing-impaired students also affect their cognitive skills such as memory in addition to communication skills. Hence, the aim of this study was to compare visual working memory in deaf and hearing-impaired students with that in normal counterparts.Method: In the present study, which was a causal-comparative study using the André Rey test, 30 deaf and 30 hearing-impaired students were compared with 30 students in a normal group, and they were matched based on gender, intelligence, educational grade, and socioeconomic status.Findings: Findings show that there is significant difference between the three groups’ subjects (p0.05.Conclusion: Function of deaf or hard-of-hearing students in the visual working memory task was weaker in comparison with the normal counterparts, while the two deaf and hard-of-hearing groups have similar functions. With a better identification and understanding of the factors that affect the development of this cognitive ability, we can offer new methods of teaching and reduce many of the disadvantages of this group of people in the different fields of cognitive science.
Mutation of Dcdc2 in mice leads to impairments in auditory processing and memory ability.

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Truong, D T; Che, A; Rendall, A R; Szalkowski, C E; LoTurco, J J; Galaburda, A M; Holly Fitch, R

2014-11-01

Dyslexia is a complex neurodevelopmental disorder characterized by impaired reading ability despite normal intellect, and is associated with specific difficulties in phonological and rapid auditory processing (RAP), visual attention and working memory. Genetic variants in Doublecortin domain-containing protein 2 (DCDC2) have been associated with dyslexia, impairments in phonological processing and in short-term/working memory. The purpose of this study was to determine whether sensory and behavioral impairments can result directly from mutation of the Dcdc2 gene in mice. Several behavioral tasks, including a modified pre-pulse inhibition paradigm (to examine auditory processing), a 4/8 radial arm maze (to assess/dissociate working vs. reference memory) and rotarod (to examine sensorimotor ability and motor learning), were used to assess the effects of Dcdc2 mutation. Behavioral results revealed deficits in RAP, working memory and reference memory in Dcdc2(del2/del2) mice when compared with matched wild types. Current findings parallel clinical research linking genetic variants of DCDC2 with specific impairments of phonological processing and memory ability. © 2014 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.
Delay-dependent working memory impairment in young-adult and aged 5-HT1BKO mice as assessed in a radial-arm water maze.

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Wolff, Mathieu; Benhassine, Narimane; Costet, Pierre; Hen, Rene; Segu, Louis; Buhot, Marie-Christine

2003-01-01

Serotonin (5-HT) plays a modulatory role in mnemonic functions, especially by interacting with the cholinergic system. The 5-HT1B receptor is a key target of this interaction. The 5-HT1B receptor knockout mice were found previously to exhibit a facilitation in hippocampal-dependent spatial reference memory learning. In the present study, we submitted mice to a delayed spatial working memory task, allowing the introduction of various delays between an exposure trial and a test trial. The 5-HT1BKO and wild-type mice learned the task in a radial-arm water maze (returning to the most recent presented arm containing the escape platform), and exhibited a high level of performance at delays of 0 and 5 min. However, at the delay of 60 min, only 5-HT1BKO mice exhibited an impairment. At a delay of 90 min, all mice were impaired. Treatment by scopolamine (0.8 mg/kg) induced the same pattern of performance in wild type as did the mutation for short (5 min, no impairment) and long (60 min, impairment) delays. The 22-month-old wild-type and knockout mice exhibited an impairment at short delays (5 and 15 min). The effect of the mutation affected both young-adult and aged mice at delays of 15, 30, and 60 min. Neurobiological data show that stimulation of the 5-HT1B receptor inhibits the release of acetylcholine in the hippocampus, but stimulates this in the frontal cortex. This dual function might, at least in part, explain the opposite effect of the mutation on reference memory (facilitation) and delay-dependent working memory (impairment). These results support the idea that cholinergic-serotonergic interactions play an important role in memory processes.
The relation between receptive grammar and procedural, declarative, and working memory in specific language impairment

OpenAIRE

Conti-Ramsden, Gina; Ullman, Michael T.; Lum, Jarrad A. G.

2015-01-01

What memory systems underlie grammar in children, and do these differ between typically developing children and children with specific language impairment (SLI)? Whilst there is substantial evidence linking certain memory deficits to the language problems in children with SLI, few studies have investigated multiple memory systems simultaneously, examining not only possible memory deficits but also memory abilities that may play a compensatory role. This study examined the extent to which proc...
Effects of noise and working memory capacity on memory processing of speech for hearing-aid users.

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Ng, Elaine Hoi Ning; Rudner, Mary; Lunner, Thomas; Pedersen, Michael Syskind; Rönnberg, Jerker

2013-07-01

It has been shown that noise reduction algorithms can reduce the negative effects of noise on memory processing in persons with normal hearing. The objective of the present study was to investigate whether a similar effect can be obtained for persons with hearing impairment and whether such an effect is dependent on individual differences in working memory capacity. A sentence-final word identification and recall (SWIR) test was conducted in two noise backgrounds with and without noise reduction as well as in quiet. Working memory capacity was measured using a reading span (RS) test. Twenty-six experienced hearing-aid users with moderate to moderately severe sensorineural hearing loss. Noise impaired recall performance. Competing speech disrupted memory performance more than speech-shaped noise. For late list items the disruptive effect of the competing speech background was virtually cancelled out by noise reduction for persons with high working memory capacity. Noise reduction can reduce the adverse effect of noise on memory for speech for persons with good working memory capacity. We argue that the mechanism behind this is faster word identification that enhances encoding into working memory.
Working memory and attention are still impaired after three years in patients with stress-related exhaustion.

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Jonsdottir, Ingibjörg H; Nordlund, Arto; Ellbin, Susanne; Ljung, Thomas; Glise, Kristina; Währborg, Peter; Sjörs, Anna; Wallin, Anders

2017-12-01

Cognitive impairment is one of the most pronounced symptoms reported by patients with stress-related mental health problems. Impairments related to executive function and to some extent speed and attention are therefore common in patients with stress-related burnout/exhaustion. In this paper we present a follow-up of cognitive performance in patients with stress-related exhaustion several years after they initially sought medical care. Thirty patients and 27 healthy controls, mean age 49 years (SD 6.5) and 55 years (SD 6.7) respectively, were included, all of whom had undergone baseline measurements of neuropsychological functioning. The mean follow-up time was three years. Half of the patients still reported mental health problems at follow-up and over time no major changes in cognitive performance were noted. The patients still performed significantly poorer than controls with regard to cognitive functions, mainly related to speed, attention and memory function. Long-lasting impairment of cognitive functions related to speed, attention and memory function noted in patients with stress-related exhaustion should be acknowledged and taken into consideration during treatment and when discussing a return to work. Follow-up periods longer than three years are needed to explore the persistence of the cognitive impairment. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.
Predictors of Verbal Working Memory in Children with Cerebral Palsy

Science.gov (United States)

Peeters, Marieke; Verhoeven, Ludo; de Moor, Jan

2009-01-01

The goal of the present study was to examine the precursors of verbal working memory in 52 children with cerebral palsy with varying degrees of speech impairments in the first grade of special education. Following Baddeley's model of working memory, children's verbal working memory was measured by means of a forced-recognition task. As precursors…
Extent and neural basis of semantic memory impairment in mild cognitive impairment.

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Barbeau, Emmanuel J; Didic, Mira; Joubert, Sven; Guedj, Eric; Koric, Lejla; Felician, Olivier; Ranjeva, Jean-Philippe; Cozzone, Patrick; Ceccaldi, Mathieu

2012-01-01

An increasing number of studies indicate that semantic memory is impaired in mild cognitive impairment (MCI). However, the extent and the neural basis of this impairment remain unknown. The aim of the present study was: 1) to evaluate whether all or only a subset of semantic domains are impaired in MCI patients; and 2) to assess the neural substrate of the semantic impairment in MCI patients using voxel-based analysis of MR grey matter density and SPECT perfusion. 29 predominantly amnestic MCI patients and 29 matched control subjects participated in this study. All subjects underwent a full neuropsychological assessment, along with a battery of five tests evaluating different domains of semantic memory. A semantic memory composite Z-score was established on the basis of this battery and was correlated with MRI grey matter density and SPECT perfusion measures. MCI patients were found to have significantly impaired performance across all semantic tasks, in addition to their anterograde memory deficit. Moreover, no temporal gradient was found for famous faces or famous public events and knowledge for the most remote decades was also impaired. Neuroimaging analyses revealed correlations between semantic knowledge and perirhinal/entorhinal areas as well as the anterior hippocampus. Therefore, the deficits in the realm of semantic memory in patients with MCI is more widespread than previously thought and related to dysfunction of brain areas beyond the limbic-diencephalic system involved in episodic memory. The severity of the semantic impairment may indicate a decline of semantic memory that began many years before the patients first consulted.
Working memory capacity predicts the beneficial effect of selective memory retrieval.

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Schlichting, Andreas; Aslan, Alp; Holterman, Christoph; Bäuml, Karl-Heinz T

2015-01-01

Selective retrieval of some studied items can both impair and improve recall of the other items. This study examined the role of working memory capacity (WMC) for the two effects of memory retrieval. Participants studied an item list consisting of predefined target and nontarget items. After study of the list, half of the participants performed an imagination task supposed to induce a change in mental context, whereas the other half performed a counting task which does not induce such context change. Following presentation of a second list, memory for the original list's target items was tested, either with or without preceding retrieval of the list's nontarget items. Consistent with previous work, preceding nontarget retrieval impaired target recall in the absence of the context change, but improved target recall in its presence. In particular, there was a positive relationship between WMC and the beneficial, but not the detrimental effect of memory retrieval. On the basis of the view that the beneficial effect of memory retrieval reflects context-reactivation processes, the results indicate that individuals with higher WMC are better able to capitalise on retrieval-induced context reactivation than individuals with lower WMC.
Effects of emotional content on working memory capacity.

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Garrison, Katie E; Schmeichel, Brandon J

2018-02-13

Emotional events tend to be remembered better than neutral events, but emotional states and stimuli may also interfere with cognitive processes that underlie memory performance. The current study investigated the effects of emotional content on working memory capacity (WMC), which involves both short term storage and executive attention control. We tested competing hypotheses in a preregistered experiment (N = 297). The emotional enhancement hypothesis predicts that emotional stimuli attract attention and additional processing resources relative to neutral stimuli, thereby making it easier to encode and store emotional information in WMC. The emotional impairment hypothesis, by contrast, predicts that emotional stimuli interfere with attention control and the active maintenance of information in working memory. Participants completed a common measure of WMC (the operation span task; Turner, M. L., & Engle, R. W. [1989]. Is working memory capacity task dependent? Journal of Memory and Language, 28, 127-154) that included either emotional or neutral words. Results revealed that WMC was reduced for emotional words relative to neutral words, consistent with the emotional impairment hypothesis.
Positive emotion can protect against source memory impairment.

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MacKenzie, Graham; Powell, Tim F; Donaldson, David I

2015-01-01

Despite widespread belief that memory is enhanced by emotion, evidence also suggests that emotion can impair memory. Here we test predictions inspired by object-based binding theory, which states that memory enhancement or impairment depends on the nature of the information to be retrieved. We investigated emotional memory in the context of source retrieval, using images of scenes that were negative, neutral or positive in valence. At study each scene was paired with a colour and during retrieval participants reported the source colour for recognised scenes. Critically, we isolated effects of valence by equating stimulus arousal across conditions. In Experiment 1 colour borders surrounded scenes at study: memory impairment was found for both negative and positive scenes. Experiment 2 used colours superimposed over scenes at study: valence affected source retrieval, with memory impairment for negative scenes only. These findings challenge current theories of emotional memory by showing that emotion can impair memory for both intrinsic and extrinsic source information, even when arousal is equated between emotional and neutral stimuli, and by dissociating the effects of positive and negative emotion on episodic memory retrieval.

A metacognitive visuospatial working memory training for children

Directory of Open Access Journals (Sweden)

Sara Caviola

2009-10-01

Full Text Available The paper studies whether visuospatial working memory (VSWM and, specifically, recall of sequential-spatial information, can be improved by metacognitive training. Twenty-two fourth-grade children were involved in seven sessions of sequential-spatial memory training, while twenty-four children attended lessons given by their teacher. The posttraining evaluation demonstrated a specific improvement of performances in the Corsi blocks task, considered a sequential-spatial working memory task. However, no benefits of training were observed in either a verbal working memory task or a simultaneous-spatial working memory task. The results have important theoretical implications, in the study of VSWM components, and educational implications, in catering for children with specific VSWM impairments.
Working memory and flexibility in awareness and attention.

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Bunting, Michael F; Cowan, Nelson

2005-06-01

We argue that attention and awareness form the basis of one type of working-memory storage. In contrast to models of working memory in which storage and retrieval occur effortlessly, we document that an attention-demanding goal conflict within a retrieval cue impairs recall from working memory. In a conceptual span task, semantic and color-name cues prompted recall of four consecutive words from a twelve-word list. The first-four, middle-four, and final-four words belonged to different semantic categories (e.g., body parts, animals, and tools) and were shown in different colors (e.g., red, blue, and green). In Experiment 1, the color of the cue matched that of cued items 75% of the time, and the rare mismatch impaired recall. In Experiment 2, though, the color of the cue matched that of the cued items only 25% of the time, and the now-more-frequent mismatches no longer mattered. These results are difficult to explain with passive storage alone and indicate that a processing difficulty impedes recall from working memory, presumably by distracting attention away from its storage function.
GABA level, gamma oscillation, and working memory performance in schizophrenia.

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Chen, Chi-Ming A; Stanford, Arielle D; Mao, Xiangling; Abi-Dargham, Anissa; Shungu, Dikoma C; Lisanby, Sarah H; Schroeder, Charles E; Kegeles, Lawrence S

2014-01-01

A relationship between working memory impairment, disordered neuronal oscillations, and abnormal prefrontal GABA function has been hypothesized in schizophrenia; however, in vivo GABA measurements and gamma band neural synchrony have not yet been compared in schizophrenia. This case-control pilot study (N = 24) compared baseline and working memory task-induced neuronal oscillations acquired with high-density electroencephalograms (EEGs) to GABA levels measured in vivo with magnetic resonance spectroscopy. Working memory performance, baseline GABA level in the left dorsolateral prefrontal cortex (DLPFC), and measures of gamma oscillations from EEGs at baseline and during a working memory task were obtained. A major limitation of this study is a relatively small sample size for several analyses due to the integration of diverse methodologies and participant compliance. Working memory performance was significantly lower for patients than for controls. During the working memory task, patients (n = 7) had significantly lower amplitudes in gamma oscillations than controls (n = 9). However, both at rest and across working memory stages, there were significant correlations between gamma oscillation amplitude and left DLPFC GABA level. Peak gamma frequency during the encoding stage of the working memory task (n = 16) significantly correlated with GABA level and working memory performance. Despite gamma band amplitude deficits in patients across working memory stages, both baseline and working memory-induced gamma oscillations showed strong dependence on baseline GABA levels in patients and controls. These findings suggest a critical role for GABA function in gamma band oscillations, even under conditions of system and cognitive impairments as seen in schizophrenia.
Shared neuroanatomical substrates of impaired phonological working memory across reading disability and autism.

Science.gov (United States)

Lu, Chunming; Qi, Zhenghan; Harris, Adrianne; Weil, Lisa Wisman; Han, Michelle; Halverson, Kelly; Perrachione, Tyler K; Kjelgaard, Margaret; Wexler, Kenneth; Tager-Flusberg, Helen; Gabrieli, John D E

2016-03-01

Individuals with reading disability or individuals with autism spectrum disorder (ASD) are characterized, respectively, by their difficulties in reading or social communication, but both groups often have impaired phonological working memory (PWM). It is not known whether the impaired PWM reflects distinct or shared neuroanatomical abnormalities in these two diagnostic groups. White-matter structural connectivity via diffusion weighted imaging was examined in sixty-four children, ages 5-17 years, with reading disability, ASD, or typical development (TD), who were matched in age, gender, intelligence, and diffusion data quality. Children with reading disability and children with ASD exhibited reduced PWM compared to children with TD. The two diagnostic groups showed altered white-matter microstructure in the temporo-parietal portion of the left arcuate fasciculus (AF) and in the temporo-occipital portion of the right inferior longitudinal fasciculus (ILF), as indexed by reduced fractional anisotropy and increased radial diffusivity. Moreover, the structural integrity of the right ILF was positively correlated with PWM ability in the two diagnostic groups, but not in the TD group. These findings suggest that impaired PWM is transdiagnostically associated with shared neuroanatomical abnormalities in ASD and reading disability. Microstructural characteristics in left AF and right ILF may play important roles in the development of PWM. The right ILF may support a compensatory mechanism for children with impaired PWM.
Toxoplasma gondii impairs memory in infected seniors.

Science.gov (United States)

Gajewski, Patrick D; Falkenstein, Michael; Hengstler, Jan G; Golka, Klaus

2014-02-01

Almost 30% of humans present a Toxoplasma gondii positive antibody status and its prevalence increases with age. The central nervous system is the main target. However, little is known about the influence of asymptomatic i.e. latent Toxoplasmosis on cognitive functions in humans. To investigate neurocognitive dysfunctions in asymptomatic older adults with T. gondii positive antibody status a double-blinded neuropsychological study was conducted. The participants were classified from a population-based sample (N=131) of healthy participants with an age of 65 years and older into two groups with 42 individuals each: Toxoplasmosis positive (T-pos; IgG>50 IU/ml) and Toxoplasmosis negative (T-neg; IgG=0 IU/ml). The outcome measures were a computer-based working-memory test (2-back) and several standardized psychometric tests of memory and executive cognitive functions. T-pos seniors showed an impairment of different aspects of memory. The rate of correctly detected target symbols in a 2-back task was decreased by nearly 9% (P=0.020), corresponding to a performance reduction of about 35% in working memory relative to the T-neg group. Moreover, T-pos seniors had a lower performance in a verbal memory test, both regarding immediate recall (10% reduction; P=0.022), delayed recognition (6%; P=0.037) and recall from long-term memory assessed by the word fluency tests (12%; P=0.029). In contrast, executive functions were not affected. The effects remained mostly unchanged after controlling for medication. The impairment of memory functions in T-pos seniors was accompanied by a decreased self-reported quality of life. Because of the high prevalence of asymptomatic Toxoplasmosis and an increasing population of older adults this finding is of high relevance for public health. Copyright © 2013 Elsevier Inc. All rights reserved.
The relationship between working memory and episodic memory disorders in transient global amnesia.

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Quinette, Peggy; Guillery-Girard, Bérengère; Noël, Audrey; de la Sayette, Vincent; Viader, Fausto; Desgranges, Béatrice; Eustache, Francis

2006-01-01

In a previous study, we investigated the relationship between the disorders of both episodic memory and working memory in the acute phase of transient global amnesia (TGA). Since executive functions were spared, another dysfunction may be responsible for the binding and maintenance of multimodal informations and contribute to the encoding disorders observed in some patients [Quinette, P., Guillery, B., Desgranges, B., de la Sayette, V., Viader, F., & Eustache, F. (2003). Working memory and executive functions in transient global amnesia. Brain, 126, 1917-1934.]. The aim of this present study was to assess the functions of binding and maintenance of multimodal information during TGA and explore their involvement in episodic memory disorders. We therefore conducted a more thorough investigation of working memory in 16 new patients during the acute phase of TGA using two tasks designed to assess the binding process and both dimensions of the maintenance, namely the active storage and the memory load ability. We also investigated the nature of the episodic memory impairment in distinguishing between the performance of patients with preferential encoding deficits and those of patients with preferential storage disorders on the episodic memory task. This distinction was closely related to the severity of amnesia, i.e. an encoding disorder was observed rather in the early phase of TGA. The results showed that while the functions of binding and maintenance of multimodal information were intact in patients with storage disorders, they were impaired in the case of encoding deficits. These results are interpreted in the recent framework of episodic buffer proposed by Baddeley [Baddeley, A. D. (2000). The episodic buffer: A new component of working memory? Trends in Cognitive Sciences, 4, 417-423] that represents an interface between working memory and episodic memory.
Novel 5-HT5A receptor antagonists ameliorate scopolamine-induced working memory deficit in mice and reference memory impairment in aged rats.

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Yamazaki, Mayako; Okabe, Mayuko; Yamamoto, Noriyuki; Yarimizu, Junko; Harada, Katsuya

2015-03-01

Despite the human 5-HT5A receptor being cloned in 1994, the biological function of this receptor has not been extensively characterized due to a lack of specific ligands. We recently reported that the selective 5-HT5A receptor antagonist ASP5736 ameliorated cognitive impairment in several animal models of schizophrenia. Given that areas of the brain with high levels of 5-HT5A receptor expression, such as the hippocampus and cerebral cortex, have important functions in cognition and memory, we evaluated the chemically diverse, potent and brain-penetrating 5-HT5A receptor antagonists ASP5736, AS2030680, and AS2674723 in rodent models of cognitive dysfunction associated with dementia. Each of these compounds exhibited a high affinity for recombinant 5-HT5A receptors that was comparable to that of the non-selective ligand of this receptor, lysergic acid diethylamide (LSD). Although each compound had a low affinity for other receptors, 5-HT5A was the only receptor for which all three compounds had a high affinity. Each of the three compounds ameliorated scopolamine-induced working memory deficit in mice and improved reference memory impairment in aged rats at similar doses. Further, ASP5736 decreased the binding of LSD to 5-HT5A receptors in the olfactory bulb of rats in a dose-dependent manner and occupied 15%-50% of brain 5-HT5A receptors at behaviorally effective doses. These results indicate that the 5-HT5A receptor is involved in learning and memory and that treatment with 5-HT5A receptor antagonists might be broadly effective for cognitive impairment associated with not only schizophrenia but also dementia. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.
History of concussion impacts electrophysiological correlates of working memory.

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Hudac, Caitlin M; Cortesa, Cathryn S; Ledwidge, Patrick S; Molfese, Dennis L

2017-10-10

Sports-related concussions occur in approximately 21% of college athletes with implications for long-term cognitive impairments in working memory. Working memory involves the capacity to maintain short-term information and integrate with higher-order cognitive processing for planning and behavior execution, critical skills for optimal cognitive and athletic performance. This study quantified working memory impairments in 36 American football college athletes (18-23years old) using event-related potentials (ERPs). Despite performing similarly in a standard 2-back working memory task, athletes with history of concussion exhibited larger P1 and P3 amplitudes compared to Controls. Concussion History group latencies were slower for the P1 and faster for the N2. Source estimation analyses indicated that previously concussed athletes engaged different brain regions compared to athletes with no concussion history. These findings suggest that ERPs may be a sensitive and objective measure to detect long-term cognitive consequences of concussion. Copyright © 2017 Elsevier B.V. All rights reserved.
The impact of specific language impairment on working memory in children with ADHD combined type

OpenAIRE

Jondottir, S.; Bouma, A.; Sergeant, J.A.; Scherder, E.J.A.

2005-01-01

The objective of this study was to examine the impact of comorbid specific language impairment (SLI) on verbal and spatial working memory in children with DSM-IV combined subtype Attention Deficit Hyperactivity Disorder (ADHD-C). Participants were a clinical sample of 81/2- to 121/2-year-old children diagnosed with ADHD-C. A group of ADHD-C with SLI was compared to a group of ADHD-C without SLI, and a group of normal children, matched on age and nonverbal intelligence. The results show that A...
Improving everyday memory performance after acquired brain injury: An RCT on recollection and working memory training.

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Richter, Kim Merle; Mödden, Claudia; Eling, Paul; Hildebrandt, Helmut

2018-04-26

To show the effectiveness of a combined recognition and working memory training on everyday memory performance in patients suffering from organic memory disorders. In this double-blind, randomized controlled Study 36 patients with organic memory impairments, mainly attributable to stroke, were assigned to either the experimental or the active control group. In the experimental group a working memory training was combined with a recollection training based on the repetition-lag procedure. Patients in the active control group received the memory therapy usually provided in the rehabilitation center. Both groups received nine hours of therapy. Prior (T0) and subsequent (T1) to the therapy, patients were evaluated on an everyday memory test (EMT) as well as on a neuropsychological test battery. Based on factor analysis of the neuropsychological test scores at T0 we calculated composite scores for working memory, verbal learning and word fluency. After treatment, the intervention group showed a significantly greater improvement for WM performance compared with the active control group. More importantly, performance on the EMT also improved significantly in patients receiving the recollection and working memory training compared with patients with standard memory training. Our results show that combining working memory and recollection training significantly improves performance on everyday memory tasks, demonstrating far transfer effects. The present study argues in favor of a process-based approach for treating memory impairments. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Symptoms of ADHD in children with high-functioning autism are related to impaired verbal working memory and verbal delayed recall.

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Andersen, Per Normann; Hovik, Kjell Tore; Skogli, Erik Winther; Egeland, Jens; Oie, Merete

2013-01-01

Symptoms similar to those found in Attention-Deficit/Hyperactivity Disorder (ADHD) often occur in children with Autism Spectrum Disorders (ASD). The objective of the current study was to compare verbal working memory, acquisition and delayed recall in children with High-Functioning Autism (HFA) to children with ADHD and typically developing children (TDC). Thirty-eight children with HFA, 79 with ADHD and 50 TDC (age 8-17) were assessed with a letter/number sequencing task and a verbal list-learning task. To investigate the possible influence of attention problems in children with HFA, we divided the HFA group into children with (HFA+) or without (HFA-) "attention problems" according to the Child Behaviour Checklist 6-18. The children with HFA+ displayed significant impairment compared to TDC on all three neurocognitive measures, while the children with HFA- were significantly impaired compared to TDC only on the working memory and acquisition measures. In addition, the HFA+ group scored significantly below the HFA- group and the ADHD group on the verbal working memory and delayed recall measures. The results support the proposition that children with HFA+, HFA-, and ADHD differ not only on a clinical level but also on a neurocognitive level which may have implications for treatment.
Symptoms of ADHD in children with high-functioning autism are related to impaired verbal working memory and verbal delayed recall.

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Per Normann Andersen

Full Text Available Symptoms similar to those found in Attention-Deficit/Hyperactivity Disorder (ADHD often occur in children with Autism Spectrum Disorders (ASD. The objective of the current study was to compare verbal working memory, acquisition and delayed recall in children with High-Functioning Autism (HFA to children with ADHD and typically developing children (TDC. Thirty-eight children with HFA, 79 with ADHD and 50 TDC (age 8-17 were assessed with a letter/number sequencing task and a verbal list-learning task. To investigate the possible influence of attention problems in children with HFA, we divided the HFA group into children with (HFA+ or without (HFA- "attention problems" according to the Child Behaviour Checklist 6-18. The children with HFA+ displayed significant impairment compared to TDC on all three neurocognitive measures, while the children with HFA- were significantly impaired compared to TDC only on the working memory and acquisition measures. In addition, the HFA+ group scored significantly below the HFA- group and the ADHD group on the verbal working memory and delayed recall measures. The results support the proposition that children with HFA+, HFA-, and ADHD differ not only on a clinical level but also on a neurocognitive level which may have implications for treatment.
The aftermath of memory retrieval for recycling visual working memory representations.

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Park, Hyung-Bum; Zhang, Weiwei; Hyun, Joo-Seok

2017-07-01

We examined the aftermath of accessing and retrieving a subset of information stored in visual working memory (VWM)-namely, whether detection of a mismatch between memory and perception can impair the original memory of an item while triggering recognition-induced forgetting for the remaining, untested items. For this purpose, we devised a consecutive-change detection task wherein two successive testing probes were displayed after a single set of memory items. Across two experiments utilizing different memory-testing methods (whole vs. single probe), we observed a reliable pattern of poor performance in change detection for the second test when the first test had exhibited a color change. The impairment after a color change was evident even when the same memory item was repeatedly probed; this suggests that an attention-driven, salient visual change made it difficult to reinstate the previously remembered item. The second change detection, for memory items untested during the first change detection, was also found to be inaccurate, indicating that recognition-induced forgetting had occurred for the unprobed items in VWM. In a third experiment, we conducted a task that involved change detection plus continuous recall, wherein a memory recall task was presented after the change detection task. The analyses of the distributions of recall errors with a probabilistic mixture model revealed that the memory impairments from both visual changes and recognition-induced forgetting are explained better by the stochastic loss of memory items than by their degraded resolution. These results indicate that attention-driven visual change and recognition-induced forgetting jointly influence the "recycling" of VWM representations.
Concurrent Working Memory Load Can Facilitate Selective Attention: Evidence for Specialized Load

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Park, Soojin; Kim, Min-Shik; Chun, Marvin M.

2007-01-01

Load theory predicts that concurrent working memory load impairs selective attention and increases distractor interference (N. Lavie, A. Hirst, J. W. de Fockert, & E. Viding, see record 2004-17825-003). Here, the authors present new evidence that the type of concurrent working memory load determines whether load impairs selective attention or not.…
Cerebellar Damage Produces Selective Deficits in Verbal Working Memory

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Ravizza, Susan M.; Mccormick, Cristin A.; Schlerf, John E.; Justus, Timothy; Ivry, Richard B.; Fiez, Julie A.

2006-01-01

The cerebellum is often active in imaging studies of verbal working memory, consistent with a putative role in articulatory rehearsal. While patients with cerebellar damage occasionally exhibit a mild impairment on standard neuropsychological tests of working memory, these tests are not diagnostic for exploring these processes in detail. The…
Functional MR imaging of working memory before neurosurgery

International Nuclear Information System (INIS)

Wunderlich, A.P.; Groen, G.; Braun, V.

2007-01-01

Information concerning the tissue adjacent to a brain tumour is crucial for planning and performing a neurosurgical intervention. In this study, we evaluated the usefulness of functional imaging of working memory in terms of working memory preservation. Working memory performance of 14 patients with prefrontal tumours was tested preoperatively by means of a standardized neuropsychological test battery. Also, functional magnetic resonance imaging (fMRI) using a so-called two-back paradigm was performed to visualize brain areas related to that task. Working memory areas were reliably detected in all patients. Surgery was then planned on the basis of this information, and the data were used for intra-operative cranial neuronavigation. Three to twelve months after surgery, patients were tested again with the test battery in order to detect possible changes in working memory performance. In 13 cases the memory performance was unchanged, only one female patient had a slight impairment of working memory compared to the pre-operative status. (orig.)
Assessment of working memory in patients with mesial temporal lobe epilepsy associated with unilateral hippocampal sclerosis.

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Tudesco, Ivanda de Souza Silva; Vaz, Leonardo José; Mantoan, Marcele Araújo Silva; Belzunces, Erich; Noffs, Maria Helena; Caboclo, Luís Otávio Sales Ferreira; Yacubian, Elza Márcia Targas; Sakamoto, Américo Ceiki; Bueno, Orlando Francisco Amodeo

2010-07-01

The aim of the present study was to investigate whether working memory is impaired in mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS), a controversial and largely unexplored matter. Twenty subjects with left MTLE-HS, 19 with right MTLE-HS, and 21 control right-handed subjects underwent neuropsychological assessment of episodic and semantic memory, executive functions, and specific working memory components. Left and right epileptogenic foci resulted in impairment of verbal and nonverbal episodic memory (verbal memory deficit greater in left MTLE-HS than in right MTLE-HS). In addition, patients with left MTLE-HS were impaired in learning paired associates, verbal fluency, and Trail Making. No differences were seen in the tests carried out to evaluate the working memory components (except visuospatial short-term memory in right MTLE-HS). In this study we did not detect reliable working memory impairment in patients with MTLE-HS with either a left or right focus in most tasks considered as tests of working memory components. Copyright 2010 Elsevier Inc. All rights reserved.
Sentence processing and verbal working memory in a white-matter-disconnection patient.

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Meyer, Lars; Cunitz, Katrin; Obleser, Jonas; Friederici, Angela D

2014-08-01

The Arcuate Fasciculus/Superior Longitudinal Fasciculus (AF/SLF) is the white-matter bundle that connects posterior superior temporal and inferior frontal cortex. Its causal functional role in sentence processing and verbal working memory is currently under debate. While impairments of sentence processing and verbal working memory often co-occur in patients suffering from AF/SLF damage, it is unclear whether these impairments result from shared white-matter damage to the verbal-working-memory network. The present study sought to specify the behavioral consequences of focal AF/SLF damage for sentence processing and verbal working memory, which were assessed in a single patient suffering from a cleft-like lesion spanning the deep left superior temporal gyrus, sparing most surrounding gray matter. While tractography suggests that the ventral fronto-temporal white-matter bundle is intact in this patient, the AF/SLF was not visible to tractography. In line with the hypothesis that the AF/SLF is causally involved in sentence processing, the patient׳s performance was selectively impaired on sentences that jointly involve both complex word orders and long word-storage intervals. However, the patient was unimpaired on sentences that only involved long word-storage intervals without involving complex word orders. On the contrary, the patient performed generally worse than a control group across standard verbal-working-memory tests. We conclude that the AF/SLF not only plays a causal role in sentence processing, linking regions of the left dorsal inferior frontal gyrus to the temporo-parietal region, but moreover plays a crucial role in verbal working memory, linking regions of the left ventral inferior frontal gyrus to the left temporo-parietal region. Together, the specific sentence-processing impairment and the more general verbal-working-memory impairment may imply that the AF/SLF subserves both sentence processing and verbal working memory, possibly pointing to the AF
The relation between receptive grammar and procedural, declarative, and working memory in specific language impairment.

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Conti-Ramsden, Gina; Ullman, Michael T; Lum, Jarrad A G

2015-01-01

What memory systems underlie grammar in children, and do these differ between typically developing (TD) children and children with specific language impairment (SLI)? Whilst there is substantial evidence linking certain memory deficits to the language problems in children with SLI, few studies have investigated multiple memory systems simultaneously, examining not only possible memory deficits but also memory abilities that may play a compensatory role. This study examined the extent to which procedural, declarative, and working memory abilities predict receptive grammar in 45 primary school aged children with SLI (30 males, 15 females) and 46 TD children (30 males, 16 females), both on average 9;10 years of age. Regression analyses probed measures of all three memory systems simultaneously as potential predictors of receptive grammar. The model was significant, explaining 51.6% of the variance. There was a significant main effect of learning in procedural memory and a significant group × procedural learning interaction. Further investigation of the interaction revealed that procedural learning predicted grammar in TD but not in children with SLI. Indeed, procedural learning was the only predictor of grammar in TD. In contrast, only learning in declarative memory significantly predicted grammar in SLI. Thus, different memory systems are associated with receptive grammar abilities in children with SLI and their TD peers. This study is, to our knowledge, the first to demonstrate a significant group by memory system interaction in predicting grammar in children with SLI and their TD peers. In line with Ullman's Declarative/Procedural model of language and procedural deficit hypothesis of SLI, variability in understanding sentences of varying grammatical complexity appears to be associated with variability in procedural memory abilities in TD children, but with declarative memory, as an apparent compensatory mechanism, in children with SLI.
Working Memory From the Psychological and Neurosciences Perspectives: A Review.

Science.gov (United States)

Chai, Wen Jia; Abd Hamid, Aini Ismafairus; Abdullah, Jafri Malin

2018-01-01

Since the concept of working memory was introduced over 50 years ago, different schools of thought have offered different definitions for working memory based on the various cognitive domains that it encompasses. The general consensus regarding working memory supports the idea that working memory is extensively involved in goal-directed behaviors in which information must be retained and manipulated to ensure successful task execution. Before the emergence of other competing models, the concept of working memory was described by the multicomponent working memory model proposed by Baddeley and Hitch. In the present article, the authors provide an overview of several working memory-relevant studies in order to harmonize the findings of working memory from the neurosciences and psychological standpoints, especially after citing evidence from past studies of healthy, aging, diseased, and/or lesioned brains. In particular, the theoretical framework behind working memory, in which the related domains that are considered to play a part in different frameworks (such as memory's capacity limit and temporary storage) are presented and discussed. From the neuroscience perspective, it has been established that working memory activates the fronto-parietal brain regions, including the prefrontal, cingulate, and parietal cortices. Recent studies have subsequently implicated the roles of subcortical regions (such as the midbrain and cerebellum) in working memory. Aging also appears to have modulatory effects on working memory; age interactions with emotion, caffeine and hormones appear to affect working memory performances at the neurobiological level. Moreover, working memory deficits are apparent in older individuals, who are susceptible to cognitive deterioration. Another younger population with working memory impairment consists of those with mental, developmental, and/or neurological disorders such as major depressive disorder and others. A less coherent and organized neural

GABA level, gamma oscillation, and working memory performance in schizophrenia

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Chi-Ming A. Chen

2014-01-01

Full Text Available A relationship between working memory impairment, disordered neuronal oscillations, and abnormal prefrontal GABA function has been hypothesized in schizophrenia; however, in vivo GABA measurements and gamma band neural synchrony have not yet been compared in schizophrenia. This case–control pilot study (N = 24 compared baseline and working memory task-induced neuronal oscillations acquired with high-density electroencephalograms (EEGs to GABA levels measured in vivo with magnetic resonance spectroscopy. Working memory performance, baseline GABA level in the left dorsolateral prefrontal cortex (DLPFC, and measures of gamma oscillations from EEGs at baseline and during a working memory task were obtained. A major limitation of this study is a relatively small sample size for several analyses due to the integration of diverse methodologies and participant compliance. Working memory performance was significantly lower for patients than for controls. During the working memory task, patients (n = 7 had significantly lower amplitudes in gamma oscillations than controls (n = 9. However, both at rest and across working memory stages, there were significant correlations between gamma oscillation amplitude and left DLPFC GABA level. Peak gamma frequency during the encoding stage of the working memory task (n = 16 significantly correlated with GABA level and working memory performance. Despite gamma band amplitude deficits in patients across working memory stages, both baseline and working memory-induced gamma oscillations showed strong dependence on baseline GABA levels in patients and controls. These findings suggest a critical role for GABA function in gamma band oscillations, even under conditions of system and cognitive impairments as seen in schizophrenia.
Working memory and new learning following pediatric traumatic brain injury.

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Mandalis, Anna; Kinsella, Glynda; Ong, Ben; Anderson, Vicki

2007-01-01

Working memory (WM), the ability to monitor, process and maintain task relevant information on-line to respond to immediate environmental demands, is controlled by frontal systems (D'Esposito et al., 2006), which are particularly vulnerable to damage from a traumatic brain injury (TBI). This study employed the adult-based Working Memory model of Baddeley and Hitch (1974) to examine the relationship between working memory function and new verbal learning in children with TBI. A cross-sectional sample of 36 school-aged children with a moderate to severe TBI was compared to age-matched healthy Controls on a series of tasks assessing working memory subsystems: the Phonological Loop (PL) and Central Executive (CE). The TBI group performed significantly more poorly than Controls on the PL measure and the majority of CE tasks. On new learning tasks, the TBI group consistently produced fewer words than Controls across the learning and delayed recall phases. Results revealed impaired PL function related to poor encoding and acquisition on a new verbal learning task in the TBI group. CE retrieval deficits in the TBI group contributed to general memory dysfunction in acquisition, retrieval and recognition memory. These results suggest that the nature of learning and memory deficits in children with TBI is related to working memory impairment.
Working Memory From the Psychological and Neurosciences Perspectives: A Review

Directory of Open Access Journals (Sweden)

Wen Jia Chai

2018-03-01

Full Text Available Since the concept of working memory was introduced over 50 years ago, different schools of thought have offered different definitions for working memory based on the various cognitive domains that it encompasses. The general consensus regarding working memory supports the idea that working memory is extensively involved in goal-directed behaviors in which information must be retained and manipulated to ensure successful task execution. Before the emergence of other competing models, the concept of working memory was described by the multicomponent working memory model proposed by Baddeley and Hitch. In the present article, the authors provide an overview of several working memory-relevant studies in order to harmonize the findings of working memory from the neurosciences and psychological standpoints, especially after citing evidence from past studies of healthy, aging, diseased, and/or lesioned brains. In particular, the theoretical framework behind working memory, in which the related domains that are considered to play a part in different frameworks (such as memory’s capacity limit and temporary storage are presented and discussed. From the neuroscience perspective, it has been established that working memory activates the fronto-parietal brain regions, including the prefrontal, cingulate, and parietal cortices. Recent studies have subsequently implicated the roles of subcortical regions (such as the midbrain and cerebellum in working memory. Aging also appears to have modulatory effects on working memory; age interactions with emotion, caffeine and hormones appear to affect working memory performances at the neurobiological level. Moreover, working memory deficits are apparent in older individuals, who are susceptible to cognitive deterioration. Another younger population with working memory impairment consists of those with mental, developmental, and/or neurological disorders such as major depressive disorder and others. A less coherent
Working Memory From the Psychological and Neurosciences Perspectives: A Review

Science.gov (United States)

Chai, Wen Jia; Abd Hamid, Aini Ismafairus; Abdullah, Jafri Malin

2018-01-01

Since the concept of working memory was introduced over 50 years ago, different schools of thought have offered different definitions for working memory based on the various cognitive domains that it encompasses. The general consensus regarding working memory supports the idea that working memory is extensively involved in goal-directed behaviors in which information must be retained and manipulated to ensure successful task execution. Before the emergence of other competing models, the concept of working memory was described by the multicomponent working memory model proposed by Baddeley and Hitch. In the present article, the authors provide an overview of several working memory-relevant studies in order to harmonize the findings of working memory from the neurosciences and psychological standpoints, especially after citing evidence from past studies of healthy, aging, diseased, and/or lesioned brains. In particular, the theoretical framework behind working memory, in which the related domains that are considered to play a part in different frameworks (such as memory’s capacity limit and temporary storage) are presented and discussed. From the neuroscience perspective, it has been established that working memory activates the fronto-parietal brain regions, including the prefrontal, cingulate, and parietal cortices. Recent studies have subsequently implicated the roles of subcortical regions (such as the midbrain and cerebellum) in working memory. Aging also appears to have modulatory effects on working memory; age interactions with emotion, caffeine and hormones appear to affect working memory performances at the neurobiological level. Moreover, working memory deficits are apparent in older individuals, who are susceptible to cognitive deterioration. Another younger population with working memory impairment consists of those with mental, developmental, and/or neurological disorders such as major depressive disorder and others. A less coherent and organized
What part of working memory is not working in ADHD? Short-term memory, the central executive and effects of reinforcement

NARCIS (Netherlands)

Dovis, S.; van der Oord, S.; Wiers, R.W.; Prins, P.J.M.

2013-01-01

Deficits in Working Memory (WM) are related to symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD). In children with ADHD visuospatial WM is most impaired. WM is composed of Short-Term Memory (STM) and a Central Executive (CE). Therefore, deficits in either or both STM and the CE may account
Working memory assessment in schizophrenia and its correlation with executive functions ability.

Science.gov (United States)

Berberian, Arthur A; Trevisan, Bruna T; Moriyama, Tais S; Montiel, José M; Oliveira, José Ari C; Seabra, Alessandra G

2009-09-01

Working memory impairment is common in schizophrenia and is possibly a cause of multiple features of the disorder. However few studies have replicated such findings of impairment patterns in Brazilian samples. The main target of this study was to assess auditory and visual working memory in patients with schizophrenia, to assess if they work as separate systems, and to correlate working memory deficits with executive functions. Twenty subjects with schizophrenia and twenty healthy subjects matched by gender, age, and schooling have participated. The abilities assessed were auditory and visual working memory, selective attention, inhibitory control, cognitive flexibility, and planning. Patients showed declines in all measures evaluated, except for a measure reaction time of inhibitory control. Auditory working memory was correlated to selective attention, inhibition, flexibility and planning while Visual working memory to planning and flexibility. The present study suggests that working memory and executive functions deficits are present in patients with schizophrenia in the Brazilian sample evaluated. Alterations in executive functions may lead to incapacity of operation of processes of working memory. These findings may contribute to delineate and develop new strategies of schizophrenia treatment in the Brazilian population.
Short-term sleep deprivation impairs spatial working memory and modulates expression levels of ionotropic glutamate receptor subunits in hippocampus.

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Xie, Meilan; Yan, Jie; He, Chao; Yang, Li; Tan, Gang; Li, Chao; Hu, Zhian; Wang, Jiali

2015-06-01

Hippocampus-dependent learning memory is sensitive to sleep deprivation (SD). Although the ionotropic glutamate receptors play a vital role in synaptic plasticity and learning and memory, however, whether the expression of these receptor subunits is modulated by sleep loss remains unclear. In the present study, western blotting was performed by probing with specific antibodies against the ionotropic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits GluA1, GluA2, GluA3, and against the N-methyl-d-aspartate (NMDA) glutamate receptor subunits GluN1, GluN2A, GluN2B. In hippocampus, down regulation of surface GluA1 and GluN2A surface expression were observed in both SD groups. However, surface expression level of GluA2, GluA3, GluN1 and GluN2B was significantly up-regulated in 8h-SD rats when compared to the 4h-SD rats. In parallel with the complex changes in AMPA and NMDA receptor subunit expressions, we found the 8h-SD impaired rat spatial working memory in 30-s-delay T-maze task, whereas no impairment of spatial learning was observed in 4h-SD rats. These results indicate that sleep loss alters the relative expression levels of the AMPA and NMDA receptors, thus affects the synaptic strength and capacity for plasticity and partially contributes to spatial memory impairment. Copyright © 2015. Published by Elsevier B.V.
Cue-independent memory impairment by reactivation-coupled interference in human declarative memory.

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Zhu, Zijian; Wang, Yingying; Cao, Zhijun; Chen, Biqing; Cai, Huaqian; Wu, Yanhong; Rao, Yi

2016-10-01

Memory is a dynamic process. While memory becomes increasingly resistant to interference after consolidation, a brief reactivation renders it unstable again. Previous studies have shown that interference, when applied upon reactivation, impairs the consolidated memory, presumably by disrupting the reconsolidation of the memory. However, attempts have failed in disrupting human declarative memory, raising a question about whether declarative memory becomes unstable upon reactivation. Here, we used a double-cue/one-target paradigm, which associated the same target with two different cues in initial memory formation. Only one cue/target association was later reactivated and treated with behavioral interference. Our results showed, for the first time, that reactivation-coupled interference caused cue-independent memory impairment that generalized to other cues associated with the memory. Critically, such memory impairment appeared immediately after interference, before the reconsolidation process was completed, suggesting that common manipulations of reactivation-coupled interference procedures might disrupt other processes in addition to the reconsolidation process in human declarative memory. Copyright © 2016. Published by Elsevier B.V.
Selective memory retrieval can impair and improve retrieval of other memories.

Science.gov (United States)

Bäuml, Karl-Heinz T; Samenieh, Anuscheh

2012-03-01

Research from the past decades has shown that retrieval of a specific memory (e.g., retrieving part of a previous vacation) typically attenuates retrieval of other memories (e.g., memories for other details of the event), causing retrieval-induced forgetting. More recently, however, it has been shown that retrieval can both attenuate and aid recall of other memories (K.-H. T. Bäuml & A. Samenieh, 2010). To identify the circumstances under which retrieval aids recall, the authors examined retrieval dynamics in listwise directed forgetting, context-dependent forgetting, proactive interference, and in the absence of any induced memory impairment. They found beneficial effects of selective retrieval in listwise directed forgetting and context-dependent forgetting but detrimental effects in all the other conditions. Because context-dependent forgetting and listwise directed forgetting arguably reflect impaired context access, the results suggest that memory retrieval aids recall of memories that are subject to impaired context access but attenuates recall in the absence of such circumstances. The findings are consistent with a 2-factor account of memory retrieval and suggest the existence of 2 faces of memory retrieval. 2012 APA, all rights reserved
Frontal and parietal theta burst TMS impairs working memory for visual-spatial conjunctions.

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Morgan, Helen M; Jackson, Margaret C; van Koningsbruggen, Martijn G; Shapiro, Kimron L; Linden, David E J

2013-03-01

In tasks that selectively probe visual or spatial working memory (WM) frontal and posterior cortical areas show a segregation, with dorsal areas preferentially involved in spatial (e.g. location) WM and ventral areas in visual (e.g. object identity) WM. In a previous fMRI study [1], we showed that right parietal cortex (PC) was more active during WM for orientation, whereas left inferior frontal gyrus (IFG) was more active during colour WM. During WM for colour-orientation conjunctions, activity in these areas was intermediate to the level of activity for the single task preferred and non-preferred information. To examine whether these specialised areas play a critical role in coordinating visual and spatial WM to perform a conjunction task, we used theta burst transcranial magnetic stimulation (TMS) to induce a functional deficit. Compared to sham stimulation, TMS to right PC or left IFG selectively impaired WM for conjunctions but not single features. This is consistent with findings from visual search paradigms, in which frontal and parietal TMS selectively affects search for conjunctions compared to single features, and with combined TMS and functional imaging work suggesting that parietal and frontal regions are functionally coupled in tasks requiring integration of visual and spatial information. Our results thus elucidate mechanisms by which the brain coordinates spatially segregated processing streams and have implications beyond the field of working memory. Copyright © 2013 Elsevier Inc. All rights reserved.
The chemotherapeutic agent paclitaxel selectively impairs learning while sparing source memory and spatial memory.

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Smith, Alexandra E; Slivicki, Richard A; Hohmann, Andrea G; Crystal, Jonathon D

2017-03-01

Chemotherapeutic agents are widely used to treat patients with systemic cancer. The efficacy of these therapies is undermined by their adverse side-effect profiles such as cognitive deficits that have a negative impact on the quality of life of cancer survivors. Cognitive side effects occur across a variety of domains, including memory, executive function, and processing speed. Such impairments are exacerbated under cognitive challenges and a subgroup of patients experience long-term impairments. Episodic memory in rats can be examined using a source memory task. In the current study, rats received paclitaxel, a taxane-derived chemotherapeutic agent, and learning and memory functioning was examined using the source memory task. Treatment with paclitaxel did not impair spatial and episodic memory, and paclitaxel treated rats were not more susceptible to cognitive challenges. Under conditions in which memory was not impaired, paclitaxel treatment impaired learning of new rules, documenting a decreased sensitivity to changes in experimental contingencies. These findings provide new information on the nature of cancer chemotherapy-induced cognitive impairments, particularly regarding the incongruent vulnerability of episodic memory and new learning following treatment with paclitaxel. Copyright © 2016 Elsevier B.V. All rights reserved.
Intact and impaired conceptual memory processes in amnesia.

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Keane, M M; Gabrieli, J D; Monti, L A; Fleischman, D A; Cantor, J M; Noland, J S

1997-01-01

To examine the status of conceptual memory processes in amnesia, a conceptual memory task with implicit or explicit task instructions was given to amnesic and control groups. After studying a list of category exemplars, participants saw category labels and were asked to generate as many exemplars as possible (an implicit memory task) or to generate exemplars that had been in the prior study list (an explicit memory task). After incidental deep or shallow encoding of exemplars, amnesic patients showed normal implicit memory performance (priming), a normal levels-of-processing effect on priming, and impaired explicit memory performance. After intentional encoding of exemplars, amnesic patients showed impaired implicit and explicit memory performance. Results suggest that although amnesic patients can show impairments on implicit and explicit conceptual memory tasks, their deficit does not generalize to all conceptual memory tasks.
Visual encoding impairment in patients with schizophrenia: contribution of reduced working memory span, decreased processing speed, and affective symptoms.

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Brébion, Gildas; Stephan-Otto, Christian; Huerta-Ramos, Elena; Ochoa, Susana; Usall, Judith; Abellán-Vega, Helena; Roca, Mercedes; Haro, Josep Maria

2015-01-01

Previous research has revealed the contribution of decreased processing speed and reduced working memory span in verbal and visual memory impairment in patients with schizophrenia. The role of affective symptoms in verbal memory has also emerged in a few studies. The authors designed a picture recognition task to investigate the impact of these factors on visual encoding. Two types of pictures (black and white vs. colored) were presented under 2 different conditions of context encoding (either displayed at a specific location or in association with another visual stimulus). It was assumed that the process of encoding associated pictures was more effortful than that of encoding pictures that were presented alone. Working memory span and processing speed were assessed. In the patient group, working memory span was significantly associated with the recognition of the associated pictures but not significantly with that of the other pictures. Controlling for processing speed eliminated the patients' deficit in the recognition of the colored pictures and greatly reduced their deficit in the recognition of the black-and-white pictures. The recognition of the black-and-white pictures was inversely related to anxiety in men and to depression in women. Working memory span constrains the effortful visual encoding processes in patients, whereas processing speed decrement accounts for most of their visual encoding deficit. Affective symptoms also have an impact on visual encoding, albeit differently in men and women. PsycINFO Database Record (c) 2015 APA, all rights reserved.
Trait anxiety and impaired control of reflective attention in working memory.

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Hoshino, Takatoshi; Tanno, Yoshihiko

2016-01-01

The present study investigated whether the control of reflective attention in working memory (WM) is impaired in high trait anxiety individuals. We focused on the consequences of refreshing-a simple reflective process of thinking briefly about a just-activated representation in mind-on the subsequent processing of verbal stimuli. Participants performed a selective refreshing task, in which they initially refreshed or read one word from a three-word set, and then refreshed a non-selected item from the initial phrase or read aloud a new word. High trait anxiety individuals exhibited greater latencies when refreshing a word after experiencing the refreshing of a word from the same list of semantic associates. The same pattern was observed for reading a new word after prior refreshing. These findings suggest that high trait anxiety individuals have difficulty resolving interference from active distractors when directing reflective attention towards contents in WM or processing a visually presented word.
Discrete memory impairments in largely pure chronic users of MDMA.

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Wunderli, Michael D; Vonmoos, Matthias; Fürst, Marina; Schädelin, Katrin; Kraemer, Thomas; Baumgartner, Markus R; Seifritz, Erich; Quednow, Boris B

2017-10-01

Chronic use of 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") has repeatedly been associated with deficits in working memory, declarative memory, and executive functions. However, previous findings regarding working memory and executive function are inconclusive yet, as in most studies concomitant stimulant use, which is known to affect these functions, was not adequately controlled for. Therefore, we compared the cognitive performance of 26 stimulant-free and largely pure (primary) MDMA users, 25 stimulant-using polydrug MDMA users, and 56 MDMA/stimulant-naïve controls by applying a comprehensive neuropsychological test battery. Neuropsychological tests were grouped into four cognitive domains. Recent drug use was objectively quantified by 6-month hair analyses on 17 substances and metabolites. Considerably lower mean hair concentrations of stimulants (amphetamine, methamphetamine, methylphenidate, cocaine), opioids (morphine, methadone, codeine), and hallucinogens (ketamine, 2C-B) were detected in primary compared to polydrug users, while both user groups did not differ in their MDMA hair concentration. Cohen's d effect sizes for both comparisons, i.e., primary MDMA users vs. controls and polydrug MDMA users vs. controls, were highest for declarative memory (d primary =.90, d polydrug =1.21), followed by working memory (d primary =.52, d polydrug =.96), executive functions (d primary =.46, d polydrug =.86), and attention (d primary =.23, d polydrug =.70). Thus, primary MDMA users showed strong and relatively discrete declarative memory impairments, whereas MDMA polydrug users displayed broad and unspecific cognitive impairments. Consequently, even largely pure chronic MDMA use is associated with decreased performance in declarative memory, while additional deficits in working memory and executive functions displayed by polydrug MDMA users are likely driven by stimulant co-use. Copyright © 2017 Elsevier B.V. and ECNP. All rights reserved.
Patterns of Semantic Memory Impairment in Mild Cognitive Impairment

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Sven Joubert

2008-01-01

Full Text Available Although the semantic memory impairment has been largely documented in Alzheimer's disease, little is known about semantic memory in the preclinical phase of the disease (Mild Cognitive Impairment. The purpose of this study was to document the nature of semantic breakdown using a battery of tests assessing different aspects of conceptual knowledge: knowledge about common objects, famous people and famous public events. Results indicate that all domains of semantic memory were impaired in MCI individuals but knowledge about famous people and famous events was affected to a greater extent than knowledge about objects. This pattern of results suggests that conceptual entities with distinctive and unique properties may be more prone to semantic breakdown in MCI. In summary, results of this study support the view that genuine semantic deficits are present in MCI. It could be useful to investigate the etiological outcome of patients failing or succeeding at such tests.
Chinese Calligraphy Writing for Augmenting Attentional Control and Working Memory of Older Adults at Risk of Mild Cognitive Impairment: A Randomized Controlled Trial.

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Chan, Sam C C; Chan, Chetwyn C H; Derbie, Abiot Y; Hui, Irene; Tan, Davynn G H; Pang, Marco Y C; Lau, Stephen C L; Fong, Kenneth N K

2017-01-01

Nonpharmacological intervention for individuals with mild cognitive impairment (MCI) needs further investigation. Test efficacy of an eight-week Chinese calligraphy writing training course in improving attentional control and working memory. Ninety-nine participants with MCI were randomized into the eight-week calligraphy writing (n = 48) or control (tablet computer) training (n = 51). Outcomes of the interventions were attentional control, working memory, visual scan and processing speed. They were measured at baseline, post-training, and six-month follow-up. Calligraphy writing, when compared with control, significantly improved working memory as reflected from DST-Backward sequence (p = 0.009) and span scores (p = 0.002), and divided attention as reflected from CTT2 (p memory (span: p cognitive approach would improve working memory and to a lesser extent attentional control functions of patients with early MCI. They also demonstrate the usefulness of using mind-and-body practice for improving specific cognitive functions.
Experimentally-induced dissociation impairs visual memory.

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Brewin, Chris R; Mersaditabari, Niloufar

2013-12-01

Dissociation is a phenomenon common in a number of psychological disorders and has been frequently suggested to impair memory for traumatic events. In this study we explored the effects of dissociation on visual memory. A dissociative state was induced experimentally using a mirror-gazing task and its short-term effects on memory performance were investigated. Sixty healthy individuals took part in the experiment. Induced dissociation impaired visual memory performance relative to a control condition; however, the degree of dissociation was not associated with lower memory scores in the experimental group. The results have theoretical and practical implications for individuals who experience frequent dissociative states such as patients with posttraumatic stress disorder (PTSD). Copyright © 2013 Elsevier Inc. All rights reserved.
Neurotensin receptor 1 gene (NTSR1 polymorphism is associated with working memory.

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Jin Li

Full Text Available BACKGROUND: Recent molecular genetics studies showed significant associations between dopamine-related genes (including genes for dopamine receptors, transporters, and degradation and working memory, but little is known about the role of genes for dopamine modulation, such as those related to neurotensin (NT, in working memory. A recent animal study has suggested that NT antagonist administration impaired working memory in a learning task. The current study examined associations between NT genes and working memory among humans. METHODS: Four hundred and sixty healthy undergraduate students were assessed with a 2-back working memory paradigm. 5 SNPs in the NTSR1 gene were genotyped. 5 ANOVA tests were conducted to examine whether and how working memory differed by NTSR1 genotype, with each SNP variant as the independent variable and the average accuracy on the working memory task as the dependent variable. RESULTS: ANOVA results suggested that two SNPs in the NTSR1 gene (rs4334545 and rs6090453 were significantly associated with working memory. These results survived corrections for multiple comparisons. CONCLUSIONS: Our results demonstrated that NTSR1 SNP polymorphisms were significantly associated with variance in working memory performance among healthy adults. This result extended previous rodent studies showing that the NT deficiency impairs the working memory function. Future research should replicate our findings and extend to an examination of other dopamine modulators.
Working Memory Weaknesses in Students with ADHD: Implications for Instruction

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Martinussen, Rhonda; Major, Ashley

2011-01-01

Students with attention deficit hyperactivity disorder (ADHD) are at risk for academic underachievement. Children and youth with ADHD have been found to exhibit impairments on neuropsychological measures of executive functions, including working memory. Working memory is important to attentional control and learning. This article defines working…

Working Memory Involved in Predicting Future Outcomes Based on Past Experiences

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Dretsch, Michael N.; Tipples, Jason

2008-01-01

Deficits in working memory have been shown to contribute to poor performance on the Iowa Gambling Task [IGT: Bechara, A., & Martin, E.M. (2004). "Impaired decision making related to working memory deficits in individuals with substance addictions." "Neuropsychology," 18, 152-162]. Similarly, a secondary memory load task has been shown to impair…
Spatial Working Memory Interferes with Explicit, but Not Probabilistic Cuing of Spatial Attention

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Won, Bo-Yeong; Jiang, Yuhong V.

2015-01-01

Recent empirical and theoretical work has depicted a close relationship between visual attention and visual working memory. For example, rehearsal in spatial working memory depends on spatial attention, whereas adding a secondary spatial working memory task impairs attentional deployment in visual search. These findings have led to the proposal…
Study on EEG power and coherence in patients with mild cognitive impairment during working memory task

Institute of Scientific and Technical Information of China (English)

JIANG Zheng-yan

2005-01-01

To investigate the features of electroencephalography (EEG) power and coherence at rest and during a working memory task of patients with mild cognitive impairment (MCI). Thirty-five patients (17 males, 18 females; 52～71 years old) and 34 sex- and age-matched controls (17 males, 17 females; 51～63 years old) were recruited in the present study. Mini-Mental State Examination (MMSE) of 35 patients with MCI and 34 normal controls revealed that the scores of MCI patients did not differ significantly from those of normal controls (P＞0.05). Then, EEGs at rest and during working memory task with three levels of working memory load were recorded. The EEG power was computed over 10 channels: right and left frontal (F3, F4), central (C3,C4), parietal (P3, P4), temporal (TS, T6) and occipital (O1, O2); inter-hemispheric coherences were computed from five electrode pairs of F3-F4, C3-C4, P3-P4, T5-T6 and O1-O2 for delta (1.0～3.5 Hz), theta (4.0～7.5 Hz), alpha-1 (8.0～10.0 Hz), alpha-2 (10.5～13.0 Hz), beta-1 (13.5～18.0 Hz) and beta-2 (18.5～30.0 Hz) frequency bands. All values of the EEG power of MCI patients were found to be higher than those of normal controls at rest and during working memory tasks. Furthermore, the values of EEG power in the theta, alpha-1, alpha-2 and beta-1 bands of patients with MCI were significantly high (P＜0.05) in comparison with those of normal controls. Correlation analysis indicated a significant negative correlation between the EEG powers and MMSE scores. In addition, during working memory tasks, the EEG coherences in all bands were significantly higher in the MCI group in comparison with those in the control group (P＜0.05). However, there was no significant difference in EEG coherences between two groups at rest. These findings comprise evidence that MCI patients have higher EEG power at rest, and higher EEG power and coherence during working conditions. It suggests that MCI may be associated with compensatory processes at
High-intensity stress elicits robust cortisol increases, and impairs working memory and visuo-spatial declarative memory in Special Forces candidates: A field experiment.

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Taverniers, John; Van Ruysseveldt, Joris; Smeets, Tom; von Grumbkow, Jasper

2010-07-01

While running a selection procedure, 27 male Belgian Special Forces candidates, with a mean age of 27.4 years (SD = 5.1), were randomly assigned to a no-stress control (n = 14) or a high-intensity stress group (n = 13). Participants in the latter group were exposed to an extremely strenuous mock prisoner of war (POW) exercise. Immediately after stress or control treatment, working memory and visuo-spatial declarative memory performances were measured by the digit span (DS) test and the Rey-Osterrieth complex figure (ROCF), respectively. Concurrently, stress levels were assessed by obtaining salivary cortisol measurements and subjectively by the NASA Task Load Index (TLX). As expected, exposure to high-intensity stress led to both robust cortisol increases and significant differences in TLX scores. Stress induction also significantly impaired DS and ROCF performances. Moreover, delta cortisol increases and ROCF performance in the POW stress group showed a significant negative correlation, while DS performances followed the same tendency. Summarizing, the current findings complement and extend previous work on hormonal stress effects, and the subsequent performance deterioration on two memory tests in a unique high-intensity stress environment.
Maternal immune activation during pregnancy in rats impairs working memory capacity of the offspring.

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Murray, Brendan G; Davies, Don A; Molder, Joel J; Howland, John G

2017-05-01

Maternal immune activation during pregnancy is an environmental risk factor for psychiatric illnesses such as schizophrenia in the offspring. Patients with schizophrenia display an array of cognitive symptoms, including impaired working memory capacity. Rodent models have been developed to understand the relationship between maternal immune activation and the cognitive symptoms of schizophrenia. The present experiment was designed to test whether maternal immune activation with the viral mimetic polyinosinic:polycytidylic acid (polyI:C) during pregnancy affects working memory capacity of the offspring. Pregnant Long Evans rats were treated with either saline or polyI:C (4mg/kg; i.v.) on gestational day 15. Male offspring of the litters (2-3months of age) were subsequently trained on a nonmatching-to-sample task with odors. After a criterion was met, the rats were tested on the odor span task, which requires rats to remember an increasing span of different odors to receive food reward. Rats were tested using delays of approximately 40s during the acquisition of the task. Importantly, polyI:C- and saline-treated offspring did not differ in performance of the nonmatching-to-sample task suggesting that both groups could perform a relatively simple working memory task. In contrast, polyI:C-treated offspring had reduced span capacity in the middle and late phases of odor span task acquisition. After task acquisition, the rats were tested using the 40s delay and a 10min delay. Both groups showed a delay-dependent decrease in span, although the polyI:C-treated offspring had significantly lower spans regardless of delay. Our results support the validity of the maternal immune activation model for studying the cognitive symptoms of neurodevelopmental disorders such as schizophrenia. Copyright © 2017 Elsevier Inc. All rights reserved.
Emotion impairs extrinsic source memory--An ERP study.

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Mao, Xinrui; You, Yuqi; Li, Wen; Guo, Chunyan

2015-09-01

Substantial advancements in understanding emotional modulation of item memory notwithstanding, controversies remain as to how emotion influences source memory. Using an emotional extrinsic source memory paradigm combined with remember/know judgments and two key event-related potentials (ERPs)-the FN400 (a frontal potential at 300-500 ms related to familiarity) and the LPC (a later parietal potential at 500-700 ms related to recollection), our research investigated the impact of emotion on extrinsic source memory and the underlying processes. We varied a semantic prompt (either "people" or "scene") preceding a study item to manipulate the extrinsic source. Behavioral data indicated a significant effect of emotion on "remember" responses to extrinsic source details, suggesting impaired recollection-based source memory in emotional (both positive and negative) relative to neutral conditions. In parallel, differential FN400 and LPC amplitudes (correctly remembered - incorrectly remembered sources) revealed emotion-related interference, suggesting impaired familiarity and recollection memory of extrinsic sources associated with positive or negative items. These findings thus lend support to the notion of emotion-induced memory trade off: while enhancing memory of central items and intrinsic/integral source details, emotion nevertheless disrupts memory of peripheral contextual details, potentially impairing both familiarity and recollection. Importantly, that positive and negative items result in comparable memory impairment suggests that arousal (vs. affective valence) plays a critical role in modulating dynamic interactions among automatic and elaborate processes involved in memory. Copyright © 2015 Elsevier B.V. All rights reserved.
Impaired working memory for visual motion direction in schizophrenia: Absence of recency effects and association with psychopathology.

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Stäblein, Michael; Sieprath, Lore; Knöchel, Christian; Landertinger, Axel; Schmied, Claudia; Ghinea, Denisa; Mayer, Jutta S; Bittner, Robert A; Reif, Andreas; Oertel-Knöchel, Viola

2016-09-01

Working memory (WM) impairments are a prominent neurocognitive symptom in schizophrenia (SZ) and include deficits in memory for serial order and abnormalities in serial position effects (i.e., primacy and recency effects). Former studies predominantly focused on investigating these deficits applying verbal or static visual stimuli, but little is known about WM processes that involve dynamic visual movements. We examined WM for visual motion directions, its susceptibility to distraction and the effect of serial positioning. Twenty-three patients with paranoid SZ and 23 healthy control subjects (HC) took part in the study. We conducted an adapted Sternberg-type recognition paradigm: three random dot kinematograms (RDKs) that depicted coherent visual motion were used as stimuli and a distractor stimulus was incorporated into the task. SZ patients performed significantly worse in the WM visual motion task, when a distractor stimulus was presented. While HC showed a recency effect for later RDKs, the effect was absent in SZ patients. WM deficits were associated with more severe psychopathological symptoms, poor visual and verbal learning, and a longer duration of illness. Furthermore, SZ patients showed impairments in several other neurocognitive domains. Findings suggest that early WM processing of visual motion is susceptible to interruption and that WM impairments are associated with clinical symptoms in SZ. The absence of a recency effect is discussed in respect of 3 theoretical approaches-impaired WM for serial order information, abnormalities in early visual representations (i.e., masking effects), and deficits in later visual processing (i.e., attentional blink effect). (PsycINFO Database Record (c) 2016 APA, all rights reserved).
A comparative study of the working memory multicomponent model in psychosis and healthy controls.

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Sánchez-Torres, Ana M; Elosúa, M Rosa; Lorente-Omeñaca, Ruth; Moreno-Izco, Lucía; Cuesta, Manuel J

2015-08-01

Working memory deficits are considered nuclear deficits in psychotic disorders. However, research has not found a generalized impairment in all of the components of working memory. We aimed to assess the components of the Baddeley and Hitch working memory model: the temporary systems-the phonological loop, the visuospatial sketchpad and the episodic buffer (introduced later by Baddeley)-and the central executive system, which includes four executive functions: divided attention, updating, shifting and inhibition. We assessed working memory performance in a sample of 21 patients with a psychotic disorder and 21 healthy controls. Patients also underwent a clinical assessment. Both univariate and repeated measures ANOVAs were applied to analyze performance in the working memory components between groups. Patients with a psychotic disorder underperformed compared to the controls in all of the working memory tasks, but after controlling for age and premorbid IQ, we only found a difference in performance in the N-Back task. Repeated measures ANCOVAs showed that patients also underperformed compared to the controls in the Digit span test and the TMT task. Not all of the components of working memory were impaired in the patients. Specifically, patients' performance was impaired in the tasks selected to assess the phonological loop and the shifting executive function. Patients' also showed worse performance than controls in the N-Back task, representative of the updating executive function. However, we did not find higher impairment in the patients' performance respect to controls when increasing the loading of the task. Copyright © 2015 Elsevier Inc. All rights reserved.
Working memory training and semantic structuring improves remembering future events, not past events.

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Richter, Kim Merle; Mödden, Claudia; Eling, Paul; Hildebrandt, Helmut

2015-01-01

Objectives. Memory training in combination with practice in semantic structuring and word fluency has been shown to improve memory performance. This study investigated the efficacy of a working memory training combined with exercises in semantic structuring and word fluency and examined whether training effects generalize to other cognitive tasks. Methods. In this double-blind randomized control study, 36 patients with memory impairments following brain damage were allocated to either the experimental or the active control condition, with both groups receiving 9 hours of therapy. The experimental group received a computer-based working memory training and exercises in word fluency and semantic structuring. The control group received the standard memory therapy provided in the rehabilitation center. Patients were tested on a neuropsychological test battery before and after therapy, resulting in composite scores for working memory; immediate, delayed, and prospective memory; word fluency; and attention. Results. The experimental group improved significantly in working memory and word fluency. The training effects also generalized to prospective memory tasks. No specific effect on episodic memory could be demonstrated. Conclusion. Combined treatment of working memory training with exercises in semantic structuring is an effective method for cognitive rehabilitation of organic memory impairment. © The Author(s) 2014.
Working memory binding and episodic memory formation in aging, mild cognitive impairment, and Alzheimer's dementia

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Geldorp, B. van; Heringa, S.M.; Berg, E. van den; Olde Rikkert, M.G.M.; Biessels, G.J.; Kessels, R.P.C.

2015-01-01

INTRODUCTION: Recent studies indicate that in both normal and pathological aging working memory (WM) performance deteriorates, especially when associations have to be maintained. However, most studies typically do not assess the relationship between WM and episodic memory formation. In the present
Self-imagining enhances recognition memory in memory-impaired individuals with neurological damage.

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Grilli, Matthew D; Glisky, Elizabeth L

2010-11-01

The ability to imagine an elaborative event from a personal perspective relies on several cognitive processes that may potentially enhance subsequent memory for the event, including visual imagery, semantic elaboration, emotional processing, and self-referential processing. In an effort to find a novel strategy for enhancing memory in memory-impaired individuals with neurological damage, we investigated the mnemonic benefit of a method we refer to as self-imagining-the imagining of an event from a realistic, personal perspective. Fourteen individuals with neurologically based memory deficits and 14 healthy control participants intentionally encoded neutral and emotional sentences under three instructions: structural-baseline processing, semantic processing, and self-imagining. Findings revealed a robust "self-imagination effect (SIE)," as self-imagination enhanced recognition memory relative to deep semantic elaboration in both memory-impaired individuals, F(1, 13) = 32.11, p memory disorder nor were they related to self-reported vividness of visual imagery, semantic processing, or emotional content of the materials. The findings suggest that the SIE may depend on unique mnemonic mechanisms possibly related to self-referential processing and that imagining an event from a personal perspective makes that event particularly memorable even for those individuals with severe memory deficits. Self-imagining may thus provide an effective rehabilitation strategy for individuals with memory impairment.
Does abnormal sleep impair memory consolidation in schizophrenia?

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Dara S Manoach

2009-09-01

Full Text Available Although disturbed sleep is a prominent feature of schizophrenia, its relation to the pathophysiology, signs, and symptoms of schizophrenia remains poorly understood. Sleep disturbances are well known to impair cognition in healthy individuals. Yet, in spite of its ubiquity in schizophrenia, abnormal sleep has generally been overlooked as a potential contributor to cognitive deficits. Amelioration of cognitive deficits is a current priority of the schizophrenia research community, but most efforts to define, characterize, and quantify cognitive deficits focus on cross-sectional measures. While this approach provides a valid snapshot of function, there is now overwhelming evidence that critical aspects of learning and memory consolidation happen offline, both over time and with sleep. Initial memory encoding is followed by a prolonged period of consolidation, integration, and reorganization, that continues over days or even years. Much of this evolution of memories is mediated by sleep. This article briefly reviews (i abnormal sleep in schizophrenia, (ii sleep-dependent memory consolidation in healthy individuals, (iii recent findings of impaired sleep-dependent memory consolidation in schizophrenia, and (iv implications of impaired sleep-dependent memory consolidation in schizophrenia. This literature suggests that abnormal sleep in schizophrenia disrupts attention and impairs sleep-dependent memory consolidation and task automation. We conclude that these sleep-dependent impairments may contribute substantially to generalized cognitive deficits in schizophrenia. Understanding this contribution may open new avenues to ameliorating cognitive dysfunction and thereby improve outcome in schizophrenia.
Phenylethanoid glycosides of Pedicularis muscicola Maxim ameliorate high altitude-induced memory impairment.

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Zhou, Baozhu; Li, Maoxing; Cao, Xinyuan; Zhang, Quanlong; Liu, Yantong; Ma, Qiang; Qiu, Yan; Luan, Fei; Wang, Xianmin

2016-04-01

Exposure to hypobaric hypoxia causes oxidative stress, neuronal degeneration and apoptosis that leads to memory impairment. Though oxidative stress contributes to neuronal degeneration and apoptosis in hypobaric hypoxia, the ability for phenylethanoid glycosides of Pedicularis muscicola Maxim (PhGs) to reverse high altitude memory impairment has not been studied. Rats were supplemented with PhGs orally for a week. After the fourth day of drug administration, rats were exposed to a 7500 m altitude simulation in a specially designed animal decompression chamber for 3 days. Spatial memory was assessed by the 8-arm radial maze test before and after exposure to hypobaric hypoxia. Histological assessment of neuronal degeneration was performed by hematoxylin-eosin (HE) staining. Changes in oxidative stress markers and changes in the expression of the apoptotic marker, caspase-3, were assessed in the hippocampus. Our results demonstrated that after exposure to hypobaric hypoxia, PhGs ameliorated high altitude memory impairment, as shown by the decreased values obtained for reference memory error (RME), working memory error (WME), and total error (TE). Meanwhile, administration of PhGs decreased hippocampal reactive oxygen species levels and consequent lipid peroxidation by elevating reduced glutathione levels and enhancing the free radical scavenging enzyme system. There was also a decrease in the number of pyknotic neurons and a reduction in caspase-3 expression in the hippocampus. These findings suggest that PhGs may be used therapeutically to ameliorate high altitude memory impairment. Copyright © 2016 Elsevier Inc. All rights reserved.
Auditory working memory impairments in individuals at familial high risk for schizophrenia.

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Seidman, Larry J; Meyer, Eric C; Giuliano, Anthony J; Breiter, Hans C; Goldstein, Jill M; Kremen, William S; Thermenos, Heidi W; Toomey, Rosemary; Stone, William S; Tsuang, Ming T; Faraone, Stephen V

2012-05-01

The search for predictors of schizophrenia has accelerated with a growing focus on early intervention and prevention of psychotic illness. Studying nonpsychotic relatives of individuals with schizophrenia enables identification of markers of vulnerability for the illness independent of confounds associated with psychosis. The goal of these studies was to develop new auditory continuous performance tests (ACPTs) and evaluate their effects in individuals with schizophrenia and their relatives. We carried out two studies of auditory vigilance with tasks involving working memory (WM) and interference control with increasing levels of cognitive load to discern the information-processing vulnerabilities in a sample of schizophrenia patients, and two samples of nonpsychotic relatives of individuals with schizophrenia and controls. Study 1 assessed adults (mean age = 41), and Study 2 assessed teenagers and young adults age 13-25 (M = 19). Patients with schizophrenia were impaired on all five versions of the ACPTs, whereas relatives were impaired only on WM tasks, particularly the two interference tasks that maximize cognitive load. Across all groups, the interference tasks were more difficult to perform than the other tasks. Schizophrenia patients performed worse than relatives, who performed worse than controls. For patients, the effect sizes were large (Cohen's d = 1.5), whereas for relatives they were moderate (d = ~0.40-0.50). There was no age by group interaction in the relatives-control comparison except for participants schizophrenia.
Alpha spectral power and coherence in the patients with mild cognitive impairment during a three-level working memory task

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

Objective: The functional relationship between calculated alpha band spectral power and inter-/intra-hemispheric coherence during a three-level working memory task of patients with mild cognitive impairment (MCI) was investigated. Methods:Subjects included 35 MCI patients according to the DSM-Ⅳ criteria (mean age: 62.3, SD: 6.5) and 34 healthy controls (mean age:57.4, SD: 4.0) were selected from the community at large. All subjects performed a simple calculation and recall task with three levels of working memory load while electroencephalograph (EEG) signal was recorded. The spectral EEG power was computed over alphal (8.0～10.0 Hz) and alpha2 (10.5～13.0 Hz) frequency bands and was compared between rest stage and working memory processing stage by two-way ANOVA. Post hoc testing analyzed the differences between each two levels of working memory load during task processing. The inter-hemisphere EEG coherence of frontal (F3-F4), central (C3-C4), parietal (P3-P4), temporal (T5-T6) as well as occipital (O1-O2) was compared between MCI patients and normal controls. The EEG signals from F3-C3,F4-C4, C3-P3, C4-P4, P3-O1, P4-O2, T5-C3, T6-C4, T5-P3 and T6-P4 electrode pairs resulted from the intra-hemispheric action for alphal and alpha2 frequency bands. Result: There was significantly higher EEG power from MCI patients than from normal controls both at rest and during working memory processing. Significant differences existed between rest condition and three-level working memory tasks (P＜0.001). The inter- and intra-hemispheric coherence during working memory tasks showed a "drop to rise" tendency compared to that at rest condition. There was significantly higher coherence in MCI patients than in the controls.When task difficulties increased, the cortical connectivity of intra-hemispheric diminished while the inter-hemispheric connectivity dominantly maintained the cognitive processing in MCI patients. Conclusion: The results of the present study indicate that the
Fish Oil Supplementation Increases Event-Related Posterior Cingulate Activation in Older Adults with Subjective Memory Impairment.

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Boespflug, E L; McNamara, R K; Eliassen, J C; Schidler, M D; Krikorian, R

2016-02-01

To determine the effects of long-chain omega-3 (LCn-3) fatty acids found in fish oil, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), on cortical blood oxygen level-dependent (BOLD) activity during a working memory task in older adults with subjective memory impairment. Randomized, double-blind, placebo-controlled study. Academic medical center. Healthy older adults (62-80 years) with subjective memory impairment, but not meeting criteria for mild cognitive impairment or dementia. Fish oil (EPA+DHA: 2.4 g/d, n=11) or placebo (corn oil, n=10) for 24 weeks. Cortical BOLD response patterns during performance of a sequential letter n-back working memory task were determined at baseline and week 24 by functional magnetic resonance imaging (fMRI). At 24 weeks erythrocyte membrane EPA+DHA composition increased significantly from baseline in participants receiving fish oil (+31%, p ≤ 0.0001) but not placebo (-17%, p=0.06). Multivariate modeling of fMRI data identified a significant interaction among treatment, visit, and memory loading in the right cingulate (BA 23/24), and in the right sensorimotor area (BA 3/4). In the fish oil group, BOLD increases at 24 weeks were observed in the right posterior cingulate and left superior frontal regions during memory loading. A region-of-interest analysis indicated that the baseline to endpoint change in posterior cingulate cortex BOLD activity signal was significantly greater in the fish oil group compared with the placebo group during the 1-back (p=0.0003) and 2-back (p=0.0005) conditions. Among all participants, the change in erythrocyte EPA+DHA during the intervention was associated with performance in the 2-back working memory task (p = 0.01), and with cingulate BOLD signal during the 1-back (p = 0.005) with a trend during the 2-back (p = 0.09). Further, cingulate BOLD activity was related to performance in the 2-back condition. Dietary fish oil supplementation increases red blood cell omega-3 content
Working memory and the control of action: evidence from task switching.

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Baddeley, A; Chincotta, D; Adlam, A

2001-12-01

A series of 7 experiments used dual-task methodology to investigate the role of working memory in the operation of a simple action-control plan or program involving regular switching between addition and subtraction. Lists requiring switching were slower than blocked lists and showed 2 concurrent task effects. Demanding executive tasks impaired performance on both blocked and switched lists, whereas articulatory suppression impaired principally the switched condition. Implications for models of task switching and working memory and for the Vygotskian concept of verbal control of action are discussed.
Chronic Stress During Adolescence Impairs and Improves Learning and Memory in Adulthood

OpenAIRE

Chaby, Lauren E.; Cavigelli, Sonia A.; Hirrlinger, Amy M.; Lim, James; Warg, Kendall M.; Braithwaite, Victoria A.

2015-01-01

HIGHLIGHTS This study tested the effects of adolescent-stress on adult learning and memory. Adolescent-stressed rats had enhanced reversal learning compared to unstressed rats. Adolescent-stress exposure made working memory more vulnerable to disturbance. Adolescent-stress did not affect adult associative learning or reference memory. Exposure to acute stress can cause a myriad of cognitive impairments, but whether negative experiences continue to hinder individual as they ag...
Short-term memory impairment and arithmetical ability.

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Butterworth, B; Cipolotti, L; Warrington, E K

1996-02-01

We document the dissociation of preserved calculation skills in a patient with impaired auditory short-term memory. The patient (MRF) had a memory span of three digits. Furthermore, he showed rapid decrement in performance of single digits and letters with both auditory and visual presentation in the Brown-Peterson forgetting task. Analysis of his calculation skills revealed a normal ability to solve auditorily presented multidigit addition and subtraction problems such as 173 + 68 and to execute the Paced Auditory Serial Addition Task (Sampson, 1956, 1958; Gronwall, 1977). In addition, his performance on other tests, including arithmetic manipulation of natural numbers, decimals and fractions, approximation, magnitude, ratio, and percentage, appeared to be normal (Hitch, 1978b). It is argued that these findings require a revision of Baddeley and Hitch's (1974) concept of the function of working memory.
Effect of Sentence Length and Complexity on Working Memory Performance in Hungarian Children with Specific Language Impairment (SLI): A Cross-Linguistic Comparison

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Marton, Klara; Schwartz, Richard G.; Farkas, Lajos; Katsnelson, Valeriya

2006-01-01

Background: English-speaking children with specific language impairment (SLI) perform more poorly than their typically developing peers in verbal working memory tasks where processing and storage are simultaneously required. Hungarian is a language with a relatively free word order and a rich agglutinative morphology. Aims: To examine the effect…

Impaired temporoparietal deactivation with working memory load in antipsychotic-naïve patients with first-episode schizophrenia

DEFF Research Database (Denmark)

Nejad, Ayna B; Ebdrup, Bjørn H; Siebner, Hartwig R

2011-01-01

Abstract Objectives. Neuroimaging studies have shown abnormal task-related deactivations during working memory (WM) in schizophrenia patients with recent emphasis on brain regions within the default mode network. Using fMRI, we tested whether antipsychotic-naïve schizophrenia patients were impaired...... load. These regions activated with the no WM load condition (0-back) in both groups. Conclusions. Because 0-back activation reflects verbal attention processes, patients' persistent activation in the 1-back and 2-back conditions may reflect an inability to shift cognitive strategy with onset of WM...
Competition between items in working memory leads to forgetting

OpenAIRE

Lewis-Peacock, Jarrod A.; Norman, Kenneth A.

2014-01-01

Switching attention from one thought to the next propels our mental lives forward. However, it is unclear how this thought-juggling affects our ability to remember these thoughts. Here we show that competition between the neural representations of pictures in working memory can impair subsequent recognition of those pictures. We use pattern classifiers to decode functional magnetic resonance imaging (fMRI) data from a retro-cueing task where participants juggle two pictures in working memory....
Working memory dysfunctions predict social problem solving skills in schizophrenia.

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Huang, Jia; Tan, Shu-ping; Walsh, Sarah C; Spriggens, Lauren K; Neumann, David L; Shum, David H K; Chan, Raymond C K

2014-12-15

The current study aimed to examine the contribution of neurocognition and social cognition to components of social problem solving. Sixty-seven inpatients with schizophrenia and 31 healthy controls were administrated batteries of neurocognitive tests, emotion perception tests, and the Chinese Assessment of Interpersonal Problem Solving Skills (CAIPSS). MANOVAs were conducted to investigate the domains in which patients with schizophrenia showed impairments. Correlations were used to determine which impaired domains were associated with social problem solving, and multiple regression analyses were conducted to compare the relative contribution of neurocognitive and social cognitive functioning to components of social problem solving. Compared with healthy controls, patients with schizophrenia performed significantly worse in sustained attention, working memory, negative emotion, intention identification and all components of the CAIPSS. Specifically, sustained attention, working memory and negative emotion identification were found to correlate with social problem solving and 1-back accuracy significantly predicted the poor performance in social problem solving. Among the dysfunctions in schizophrenia, working memory contributed most to deficits in social problem solving in patients with schizophrenia. This finding provides support for targeting working memory in the development of future social problem solving rehabilitation interventions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Short-term exposure to enriched environment rescues chronic stress-induced impaired hippocampal synaptic plasticity, anxiety, and memory deficits.

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Bhagya, Venkanna Rao; Srikumar, Bettadapura N; Veena, Jayagopalan; Shankaranarayana Rao, Byrathnahalli S

2017-08-01

Exposure to prolonged stress results in structural and functional alterations in the hippocampus including reduced long-term potentiation (LTP), neurogenesis, spatial learning and working memory impairments, and enhanced anxiety-like behavior. On the other hand, enriched environment (EE) has beneficial effects on hippocampal structure and function, such as improved memory, increased hippocampal neurogenesis, and progressive synaptic plasticity. It is unclear whether exposure to short-term EE for 10 days can overcome restraint stress-induced cognitive deficits and impaired hippocampal plasticity. Consequently, the present study explored the beneficial effects of short-term EE on chronic stress-induced impaired LTP, working memory, and anxiety-like behavior. Male Wistar rats were subjected to chronic restraint stress (6 hr/day) over a period of 21 days, and then they were exposed to EE (6 hr/day) for 10 days. Restraint stress reduced hippocampal CA1-LTP, increased anxiety-like symptoms in elevated plus maze, and impaired working memory in T-maze task. Remarkably, EE facilitated hippocampal LTP, improved working memory performance, and completely overcame the effect of chronic stress on anxiety behavior. In conclusion, exposure to EE can bring out positive effects on synaptic plasticity in the hippocampus and thereby elicit its beneficial effects on cognitive functions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Emotion processing facilitates working memory performance.

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Lindström, Björn R; Bohlin, Gunilla

2011-11-01

The effect of emotional stimulus content on working memory performance has been investigated with conflicting results, as both emotion-dependent facilitation and impairments are reported in the literature. To clarify this issue, 52 adult participants performed a modified visual 2-back task with highly arousing positive stimuli (sexual scenes), highly arousing negative stimuli (violent death) and low-arousal neutral stimuli. Emotional stimulus processing was found to facilitate task performance relative to that of neutral stimuli, both in regards to response accuracy and reaction times. No emotion-dependent differences in false-alarm rates were found. These results indicate that emotional information can have a facilitating effect on working memory maintenance and processing of information.
Impaired Odor Recognition Memory in Patients with Hippocampal Lesions

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Levy, Daniel A.; Squire, Larry R.; Hopkins, Ramona O.

2004-01-01

In humans, impaired recognition memory following lesions thought to be limited to the hippocampal region has been demonstrated for a wide variety of tasks. However, the importance of the human hippocampus for olfactory recognition memory has scarcely been explored. We evaluated the ability of memory-impaired patients with damage thought to be…
Selective Attention, Working Memory, and Executive Function as Potential Independent Sources of Cognitive Dysfunction in Schizophrenia.

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Gold, James M; Robinson, Benjamin; Leonard, Carly J; Hahn, Britta; Chen, Shuo; McMahon, Robert P; Luck, Steven J

2017-11-11

People with schizophrenia demonstrate impairments in selective attention, working memory, and executive function. Given the overlap in these constructs, it is unclear if these represent distinct impairments or different manifestations of one higher-order impairment. To examine this question, we administered tasks from the basic cognitive neuroscience literature to measure visual selective attention, working memory capacity, and executive function in 126 people with schizophrenia and 122 healthy volunteers. Patients demonstrated deficits on all tasks with the exception of selective attention guided by strong bottom-up inputs. Although the measures of top-down control of selective attention, working memory, and executive function were all intercorrelated, several sources of evidence indicate that working memory and executive function are separate sources of variance. Specifically, both working memory and executive function independently contributed to the discrimination of group status and independently accounted for variance in overall general cognitive ability as assessed by the MATRICS battery. These two cognitive functions appear to be separable features of the cognitive impairments observed in schizophrenia. © The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Inferior frontal gyrus preserves working memory and emotional learning under conditions of impaired noradrenergic signaling

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Benjamin eBecker

2013-12-01

Full Text Available Compensation has been widely applied to explain neuroimaging findings in neuropsychiatric patients. Functional compensation is often invoked when patients display equal performance and increased neural activity in comparison to healthy controls. According to the compensatory hypothesis increased activity allows the brain to maintain cognitive performance despite underlying neuropathological changes. Due to methodological and pathology-related issues, however, the functional relevance of the increased activity and the specific brain regions involved in the compensatory response remain unclear. An experimental approach that allows a transient induction of compensatory responses in the healthy brain could help to overcome these issues. To this end we used the nonselective beta-blocker propranolol to pharmacologically induce sub-optimal noradrenergic signaling in healthy participants. In two independent fMRI experiments participants received either placebo or propranolol before they underwent a cognitive challenge (experiment 1: working memory; experiment 2: emotional learning: Pavlovian fear conditioning. In experiment 1 propranolol had no effects on working memory performance, but evoked stronger activity in the left inferior frontal gyrus (IFG. In experiment 2 propranolol produced no effects on emotional memory formation, but evoked stronger activity in the right IFG. The present finding that sub-optimal beta-adrenergic signaling did not disrupt performance and concomitantly increased IFG activity is consistent with, and extends, current perspectives on functional compensation. Together, our findings suggest that under conditions of impaired noradrenergic signaling, heightened activity in brain regions located within the cognitive control network, particularly the IFG, may reflect compensatory operations subserving the maintenance of behavioral performance.
Impaired executive functioning in subclinical compulsive checking with ecologically valid stimuli in a Working Memory task

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Ben eHarkin

2011-05-01

Full Text Available We previously showed that working memory performance of subclinical checkers can be affected if they are presented with irrelevant but misleading information during the retention period (Harkin & Kessler, 2009, 2010. The present study differed from our previous research in the three crucial aspects. Firstly, we employed ecologically valid stimuli in form of electrical kitchen appliances on a kitchen countertop in order to address previous criticism of our stimuli in terms of validity with respect to compulsive checking symptomatology. Secondly, we tested whether the new stimuli would allow us to employ a simpler (un-blocked design while obtaining similarly robust results. Thirdly, in Experiment 2 we improved the measure of confidence as a metacognitive variable by using a quantitative scale (0-100, which indeed revealed more robust effects that were quantitatively related to accuracy of performance. The task in the present study was to memorise four appliances, incl. their states (on/off, and their locations on the kitchen countertop. Memory accuracy was tested for the states of appliances in Experiment 1, and for their locations in Experiment 2. Intermediate probes were identical in both Experiments and were administered during retention on 2/3 of the trials with 50% resolvable and 50% misleading probes. Experiment 1 revealed a general impairment of high checkers, which confirmed the efficacy of our stimuli. In Experiment 2 we observed the expected, more differentiated pattern: High checkers were not generally affected in their WM performance (i.e., no general capacity issue; instead they showed a particular impairment in the misleading distractor-probe condition. Also, high checkers’ confidence ratings were indicative of a general impairment in metacognitive functioning.
Processing speed and working memory span: their differential role in superficial and deep memory processes in schizophrenia.

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Brébion, Gildas; Bressan, Rodrigo A; Pilowsky, Lyn S; David, Anthony S

2011-05-01

Previous work has suggested that decrement in both processing speed and working memory span plays a role in the memory impairment observed in patients with schizophrenia. We undertook a study to examine simultaneously the effect of these two factors. A sample of 49 patients with schizophrenia and 43 healthy controls underwent a battery of verbal and visual memory tasks. Superficial and deep encoding memory measures were tallied. We conducted regression analyses on the various memory measures, using processing speed and working memory span as independent variables. In the patient group, processing speed was a significant predictor of superficial and deep memory measures in verbal and visual memory. Working memory span was an additional significant predictor of the deep memory measures only. Regression analyses involving all participants revealed that the effect of diagnosis on all the deep encoding memory measures was reduced to non-significance when processing speed was entered in the regression. Decreased processing speed is involved in verbal and visual memory deficit in patients, whether the task require superficial or deep encoding. Working memory is involved only insofar as the task requires a certain amount of effort.
The hippocampus, time and working memory.

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Rawlins, J N; Tsaltas, E

1983-12-01

Rats were trained on a discrete trial working memory leverpress alternation task, following hippocampal lesions (HC), cortical control lesions (CC) or sham operations (SO). Each trial consisted of a forced information response, for which a randomly selected lever was presented followed by a free choice stage, when both levers were presented. The rats were rewarded for pressing the lever which had not been presented at the information stage. When the information response was not rewarded, all rats learnt the task equally well at IRIs of up to 12.75 sec. When the information response was rewarded, the HC rats showed impaired choice accuracy. The extent of this impairment depended on the IRI, being greatest at long IRIs, and least at short ones. Varying the number of leverpresses required to complete the information response affected choice accuracy equivalently in all groups: all rats chose significantly less accurately when only one leverpress was required than when ten leverpresses were required. There was no interaction between the lesion treatments and the information response requirements. It was concluded that both the length of the IRI and the occurrence of events during the IRI determine the extent of the hippocampal lesion-induced performance deficit in working memory tasks. It is proposed that hippocampal damage disrupts an intermediate-term, high-capacity memory buffer, but leaves both a residual short-term memory system and the long-term retention of associations unaffected. This proposal leads to the prediction that reference memory tasks should also be affected by hippocampal lesions when a delay is introduced between making a response and being rewarded for doing so.
The Impairing Role of Stress on Autobiographical Memory Reconsolidation

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Zeinab Azimi

2012-10-01

Full Text Available Background: Despite some studies indicating improving role of stress on memory consolidation, very few animal and human studies show that stress impairs reconsolidation of memories. This study aimed to determine the effect of stress on autobiographical memory reconsolidation.Materials and Methods: The present study was done with an experimental method (Solomon Four-Group design. The statistical society of this study was all undergraduate female students in 2009-2010 academic year at Tabriz University. Forty students were selected using random cluster sampling, and we ensure about their physical and mental health by GHQ-28 and interview. Tools for this study were cueing autobiographical memory test, SECPT (for raising blood pressure and stress induction, autobiographical memory test, PANAS and general health questionnaire (GHQ-28. MANOVA was used for data analysis by SPSS-17.Results: The results show that stress after activation of memory impairs memory for neutral events (p0.05. None of stress and memory activation alone had effect on memory performance (p>0.05.Conclusion: These findings indicate that stress impairs autobiographical memory reconsolidation, which is opposite to its effects on memory consolidation, so it supports the view that consolidation and reconsolidation are separate process.
Role of Auditory Non-Verbal Working Memory in Sentence Repetition for Bilingual Children with Primary Language Impairment

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Ebert, Kerry Danahy

2014-01-01

Background: Sentence repetition performance is attracting increasing interest as a valuable clinical marker for primary (or specific) language impairment (LI) in both monolingual and bilingual populations. Multiple aspects of memory appear to contribute to sentence repetition performance, but non-verbal memory has not yet been considered. Aims: To…
Working memory binding and episodic memory formation in aging, mild cognitive impairment, and Alzheimer’s dementia

NARCIS (Netherlands)

Geldorp, B. van; Heringa, S.M.; Berg, E. van den; Olde Rikkert, M.G.M.; Biessels, G.J.; Kessels, R.P.C.

2015-01-01

Introduction: Recent studies indicate that in both normal and pathological aging working memory (WM) performance deteriorates, especially when associations have to be maintained. However, most studies typically do not assess the relationship between WM and episodic memory formation. In the present
The role of inferior parietal and inferior frontal cortex in working memory.

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Baldo, Juliana V; Dronkers, Nina F

2006-09-01

Verbal working memory involves two major components: a phonological store that holds auditory-verbal information very briefly and an articulatory rehearsal process that allows that information to be refreshed and thus held longer in short-term memory (A. Baddeley, 1996, 2000; A. Baddeley & G. Hitch, 1974). In the current study, the authors tested two groups of patients who were chosen on the basis of their relatively focal lesions in the inferior parietal (IP) cortex or inferior frontal (IF) cortex. Patients were tested on a series of tasks that have been previously shown to tap phonological storage (span, auditory rhyming, and repetition) and articulatory rehearsal (visual rhyming and a 2-back task). As predicted, IP patients were disproportionately impaired on the span, rhyming, and repetition tasks and thus demonstrated a phonological storage deficit. IF patients, however, did not show impairment on these storage tasks but did exhibit impairment on the visual rhyming task, which requires articulatory rehearsal. These findings lend further support to the working memory model and provide evidence of the roles of IP and IF cortex in separable working memory processes. ((c) 2006 APA, all rights reserved).
Bombesin administration impairs memory and does not reverse memory deficit caused by sleep deprivation.

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Ferreira, L B T; Oliveira, S L B; Raya, J; Esumi, L A; Hipolide, D C

2017-07-28

Sleep deprivation impairs performance in emotional memory tasks, however this effect on memory is not completely understood. Possible mechanisms may involve an alteration in neurotransmission systems, as shown by the fact that many drugs that modulate neural pathways can prevent memory impairment by sleep loss. Gastrin releasing peptide (GRP) is a neuropeptide that emerged as a regulatory molecule of emotional memory through the modulation of other neurotransmission systems. Thus, the present study addressed the effect of intraperitoneal (IP) administration of bombesin (BB) (2.5, 5.0 and 10.0μg/kg), a GRP agonist, on the performance of Wistar rats in a multiple trail inhibitory avoidance (MTIA) task, after sleep deprivation, using the modified multiple platforms method (MMPM). Sleep deprived animals exhibited acquisition and retention impairment that was not prevented by BB injection. In addition, non-sleep deprived animals treated with BB before and after the training session, but not before the test, have shown a retention deficit. In summary, BB did not improve the memory impairment by sleep loss and, under normal conditions, produced a memory consolidation deficit. Copyright © 2017 Elsevier B.V. All rights reserved.
Impairment of Working Memory, Decision-making, and Executive Function in the First-Degree Relatives of People with Panic Disorder: A Pilot Study

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Zhenhe Zhou

2017-11-01

Full Text Available BackgroundPanic disorder (PD patients present impairments of working memory, decision-making, and executive function. However, whether the first-degree relatives (FDRs of people with PD present abnormal characteristics, including clinical and neuropsychological aspects, in comparison to the general population, has not been studied. Investigation and understanding of the abnormal neuropsychological characteristics of the FDRs of people with PD will contribute to the prevention and treatment of PD.ObjectiveThe purpose of this paper is to compare the working memory, decision-making, and executive function among people with PD, their FDRs, and controls.Materials and methodsNeuropsychological functions of 30 people with PD, 30 FDRs of people with PD, and 30 controls were measured with a digit span task, Iowa Gambling Task (IGT, and Wisconsin Card Sorting Test (WCST.ResultsPerseverative errors, failure to maintain set scores, and number of cards chosen from decks A, B, C, and D were higher for People with PD and their FDRs than those of controls. Furthermore, error rates for these tests were higher for people with PD than their FDRs. Forward scores and backward scores, percentage of conceptual level responses, the number of categories completed, choices from advantageous minus disadvantageous decks, and mean amount of money earned of people with PD and their FDRs were all lower than those of controls. Scores for these tests were also lower for people with PD than for their FDRs.ConclusionPeople with PD as well as their FDRs present different degrees of impairments of working memory, decision-making, and executive function. Impaired performance on three tasks appears to be associated with the diathesis for PD and may be a valuable indicator of susceptibility for this disorder.
GABA level, gamma oscillation, and working memory performance in schizophrenia

OpenAIRE

Chen, Chi-Ming A.; Stanford, Arielle D.; Mao, Xiangling; Abi-Dargham, Anissa; Shungu, Dikoma C.; Lisanby, Sarah H.; Schroeder, Charles E.; Kegeles, Lawrence S.

2014-01-01

A relationship between working memory impairment, disordered neuronal oscillations, and abnormal prefrontal GABA function has been hypothesized in schizophrenia; however, in vivo GABA measurements and gamma band neural synchrony have not yet been compared in schizophrenia. This case–control pilot study (N = 24) compared baseline and working memory task-induced neuronal oscillations acquired with high-density electroencephalograms (EEGs) to GABA levels measured in vivo with magnetic resonance ...
Prose recall and amnesia: implications for the structure of working memory.

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Baddeley, Alan; Wilson, Barbara A

2002-01-01

Two densely amnesic patients are shown to have good immediate but poor delayed prose recall, a result that presents problems for the current multi-component model of working memory. Examination of a wide sample of memory impaired patients suggests that this pattern occurs in densely amnesic patients who have well-preserved intelligence and good executive capacities. Patients suffering from Alzheimer's disease typically show poor immediate and delayed prose recall, reflecting their combined intellectual and memory deficits. The results are interpreted in terms of a proposed new component of working memory, the episodic buffer.
Mild cognitive impairment and prospective memory: translating the evidence into neuropsychological practice.

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Kinsella, Glynda J; Pike, Kerryn E; Cavuoto, Marina G; Lee, Stephen D

2018-04-30

There has been a recent rapid development of research characterizing prospective memory performance in mild cognitive impairment (MCI) in older age. However, this body of literature remains largely separated from routine clinical practice in neuropsychology. Furthermore, there is emerging evidence of effective interventions to improve prospective memory performance. Therefore, our objective in this article was to offer a clinical neuropsychological perspective on the existing research in order to facilitate the translation of the evidence-base into clinical practice. By conducting a critical review of the existing research related to prospective memory and MCI, we highlight how this data can be introduced into clinical practice, either within diagnostic assessment or clinical management. Prospective memory is impaired in older adults with MCI, with a pattern of performance that helps with differential diagnosis from healthy aging. Clinical neuropsychologists are encouraged to add prospective memory assessment to their toolbox for diagnostic evaluation of clients with MCI. Preliminary findings of prospective memory interventions in MCI are promising, but more work is required to determine how different approaches translate to increasing independence in everyday life.

Impaired precision, but normal retention, of auditory sensory ("echoic") memory information in schizophrenia.

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Javitt, D C; Strous, R D; Grochowski, S; Ritter, W; Cowan, N

1997-05-01

Working memory is the type of memory that allows one to hold information in mind while working on a task or problem. The present study investigated attention-independent auditory sensory ("echoic") memory in 18 schizophrenic participants and 17 controls. Schizophrenic participants showed impaired delayed tone matching performance in comparison with controls. However, when groups were matched for performance at 1 s by varying the difficulty of the task across groups, schizophrenic participants showed normal retention of information as reflected in normal tone matching performance. These findings demonstrate that schizophrenic may be in the sensitivity of the system rather than the duration for which memory traces were retained.
Cigarette smoking might impair memory and sleep quality

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Jui-Ting Liu

2013-05-01

Full Text Available Although nicotine can enhance some cognitive functions, cigarette smoking may impair memory and sleep quality. Our aim was to investigate the impact of cigarette smoking on memory and sleep quality in healthy smokers. Sixty-eight healthy participants (34 smokers and 34 controls completed the Wechsler Memory Scale-Revised and a Chinese version of the Pittsburgh Sleep Quality Index. The Wilcoxon signed ranks test was performed, and Hochberg’s Sharpened Bonferroni correction was applied for multiple comparisons. The results show that current smokers had a worse visual memory compared to nonsmokers. There was no significant correlation between the index of Wechsler Memory Scale-Revised and Fagerström test for nicotine dependence. Moreover, smokers had poorer sleep quality. Cigarette smoking might impair memory and adversely influence sleep quality.
Glucocorticoids mediate stress-induced impairment of retrieval of stimulus-response memory.

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Atsak, Piray; Guenzel, Friederike M; Kantar-Gok, Deniz; Zalachoras, Ioannis; Yargicoglu, Piraye; Meijer, Onno C; Quirarte, Gina L; Wolf, Oliver T; Schwabe, Lars; Roozendaal, Benno

2016-05-01

Acute stress and elevated glucocorticoid hormone levels are well known to impair the retrieval of hippocampus-dependent 'declarative' memory. Recent findings suggest that stress might also impair the retrieval of non-hippocampal memories. In particular, stress shortly before retention testing was shown to impair the retrieval of striatal stimulus-response associations in humans. However, the mechanism underlying this stress-induced retrieval impairment of non-hippocampal stimulus-response memory remains elusive. In the present study, we investigated whether an acute elevation in glucocorticoid levels mediates the impairing effects of stress on retrieval of stimulus-response memory. Male Sprague-Dawley rats were trained on a stimulus-response task in an eight-arm radial maze until they learned to associate a stimulus, i.e., cue, with a food reward in one of the arms. Twenty-four hours after successful acquisition, they received a systemic injection of vehicle, corticosterone (1mg/kg), the corticosterone-synthesis inhibitor metyrapone (35mg/kg) or were left untreated 1h before retention testing. We found that the corticosterone injection impaired the retrieval of stimulus-response memory. We further found that the systemic injection procedure per se was stressful as the vehicle administration also increased plasma corticosterone levels and impaired the retrieval of stimulus-response memory. However, memory retrieval was not impaired when rats were tested 2min after the systemic vehicle injection, before any stress-induced elevation in corticosterone levels had occurred. Moreover, metyrapone treatment blocked the effect of injection stress on both plasma corticosterone levels and memory retrieval impairment, indicating that the endogenous corticosterone response mediates the stress-induced memory retrieval impairment. None of the treatments affected rats' locomotor activity or motivation to search for the food reward within the maze. These findings show that stress
Survivors of cardiac arrest with good neurological outcome show considerable impairments of memory functioning.

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Sulzgruber, Patrick; Kliegel, Andreas; Wandaller, Cosima; Uray, Thomas; Losert, Heidrun; Laggner, Anton N; Sterz, Fritz; Kliegel, Matthias

2015-03-01

Deficits in cognitive function are a well-known dysfunction in survivors of cardiac arrest. However, data concerning memory function in this neurological vulnerable patient collective remain scarce and inconclusive. Therefore, we aimed to assess multiple aspects of retrospective and prospective memory performance in patients after cardiac arrest. We prospectively enrolled 33 survivors of cardiac arrest, with cerebral performance categories (CPC) 1 and 2 and a control-group (n=33) matched in sex, age and educational-level. To assess retrospective and prospective memory performance we administrated 4 weeks after cardiac arrest the "Rey Adult Learning Test" (RAVLT), the "Digit-Span-Backwards Test", the "Logic-Memory Test" and the "Red-Pencil Test". Results indicate an impairment in immediate and delayed free recall, but not in recognition. However, the overall impairment in immediate recall was qualified by analyzing RAVLT performance, showing that patients were only impaired in trials 4 and 5 of the learning sequence. Moreover, working and prospective memory as well as prose recall were worse in cardiac arrest survivors. Cranial computed tomography was available in 61% of all patients (n=20) but there was no specific neurological damage detectable that could be linked to this cognitive impairment. Episodic long-term memory functioning appears to be particularly impaired after cardiac arrest. In contrast, short-term memory storage, even tested via free-call, seems not to be affected. Based on cranial computed tomography we suggest that global brain ischemia rather than focal brain lesions appear to underlie these effects. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Dissociation of active working memory and passive recognition in rhesus monkeys

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Basile, Benjamin M.; Hampton, Robert R.

2012-01-01

Active cognitive control of working memory is central in most human memory models, but behavioral evidence for such control in nonhuman primates is absent and neurophysiological evidence, while suggestive, is indirect. We present behavioral evidence that monkey memory for familiar images is under active cognitive control. Concurrent cognitive demands during the memory delay impaired matching-to-sample performance for familiar images in a demand-dependent manner, indicating that maintaining th...
Verbal and Visual Memory Impairments in Bipolar I and II Disorder.

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Ha, Tae Hyon; Kim, Ji Sun; Chang, Jae Seung; Oh, Sung Hee; Her, Ju Young; Cho, Hyun Sang; Park, Tae Sung; Shin, Soon Young; Ha, Kyooseob

2012-12-01

To compare verbal and visual memory performances between patients with bipolar I disorder (BD I) and patients with bipolar II disorder (BD II) and to determine whether memory deficits were mediated by impaired organizational strategies. Performances on the Korean-California Verbal Learning Test (K-CVLT) and the Rey-Osterrieth Complex Figure Test (ROCF) in 37 patients with BD I, 46 patients with BD II and 42 healthy subjects were compared. Mediating effects of impaired organization strategies on poor delayed recall was tested by comparing direct and mediated models using multiple regression analysis. Both patients groups recalled fewer words and figure components and showed lower Semantic Clustering compared to controls. Verbal memory impairment was partly mediated by difficulties in Semantic Clustering in both subtypes, whereas the mediating effect of Organization deficit on the visual memory impairment was present only in BD I. In all mediated models, group differences in delayed recall remained significant. Our findings suggest that memory impairment may be one of the fundamental cognitive deficits in bipolar disorders and that executive dysfunctions can exert an additional influence on memory impairments.
Direct Electrical Stimulation of the Human Entorhinal Region and Hippocampus Impairs Memory.

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Jacobs, Joshua; Miller, Jonathan; Lee, Sang Ah; Coffey, Tom; Watrous, Andrew J; Sperling, Michael R; Sharan, Ashwini; Worrell, Gregory; Berry, Brent; Lega, Bradley; Jobst, Barbara C; Davis, Kathryn; Gross, Robert E; Sheth, Sameer A; Ezzyat, Youssef; Das, Sandhitsu R; Stein, Joel; Gorniak, Richard; Kahana, Michael J; Rizzuto, Daniel S

2016-12-07

Deep brain stimulation (DBS) has shown promise for treating a range of brain disorders and neurological conditions. One recent study showed that DBS in the entorhinal region improved the accuracy of human spatial memory. Based on this line of work, we performed a series of experiments to more fully characterize the effects of DBS in the medial temporal lobe on human memory. Neurosurgical patients with implanted electrodes performed spatial and verbal-episodic memory tasks. During the encoding periods of both tasks, subjects received electrical stimulation at 50 Hz. In contrast to earlier work, electrical stimulation impaired memory performance significantly in both spatial and verbal tasks. Stimulation in both the entorhinal region and hippocampus caused decreased memory performance. These findings indicate that the entorhinal region and hippocampus are causally involved in human memory and suggest that refined methods are needed to use DBS in these regions to improve memory. Copyright Â© 2016 Elsevier Inc. All rights reserved.
Contralateral Delay Activity Tracks Fluctuations in Working Memory Performance.

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Adam, Kirsten C S; Robison, Matthew K; Vogel, Edward K

2018-01-08

Neural measures of working memory storage, such as the contralateral delay activity (CDA), are powerful tools in working memory research. CDA amplitude is sensitive to working memory load, reaches an asymptote at known behavioral limits, and predicts individual differences in capacity. An open question, however, is whether neural measures of load also track trial-by-trial fluctuations in performance. Here, we used a whole-report working memory task to test the relationship between CDA amplitude and working memory performance. If working memory failures are due to decision-based errors and retrieval failures, CDA amplitude would not differentiate good and poor performance trials when load is held constant. If failures arise during storage, then CDA amplitude should track both working memory load and trial-by-trial performance. As expected, CDA amplitude tracked load (Experiment 1), reaching an asymptote at three items. In Experiment 2, we tracked fluctuations in trial-by-trial performance. CDA amplitude was larger (more negative) for high-performance trials compared with low-performance trials, suggesting that fluctuations in performance were related to the successful storage of items. During working memory failures, participants oriented their attention to the correct side of the screen (lateralized P1) and maintained covert attention to the correct side during the delay period (lateralized alpha power suppression). Despite the preservation of attentional orienting, we found impairments consistent with an executive attention theory of individual differences in working memory capacity; fluctuations in executive control (indexed by pretrial frontal theta power) may be to blame for storage failures.
Noradrenergic Stimulation Impairs Memory Generalization in Women.

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Kluen, Lisa Marieke; Agorastos, Agorastos; Wiedemann, Klaus; Schwabe, Lars

2017-07-01

Memory generalization is essential for adaptive decision-making and action. Our ability to generalize across past experiences relies on medial-temporal lobe structures, known to be highly sensitive to stress. Recent evidence suggests that stressful events may indeed interfere with memory generalization. Yet, the mechanisms involved in this generalization impairment are unknown. We tested here whether a pharmacological elevation of major stress mediators-noradrenaline and glucocorticoids-is sufficient to disrupt memory generalization. In a double-blind, placebo-controlled design, healthy men and women received orally a placebo, hydrocortisone, the α2-adrenoceptor antagonist yohimbine that leads to increased noradrenergic stimulation, or both drugs, before they completed an associative learning task probing memory generalization. Drugs left learning performance intact. Yohimbine, however, led to a striking generalization impairment in women, but not in men. Hydrocortisone, in turn, had no effect on memory generalization, neither in men nor in women. The present findings indicate that increased noradrenergic activity, but not cortisol, is sufficient to disrupt memory generalization in a sex-specific manner, with relevant implications for stress-related mental disorders characterized by generalization deficits.
Dissociation of Cross-Sectional Trajectories for Verbal and Visuo-Spatial Working Memory Development in Rubinstein-Taybi Syndrome

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Waite, Jane; Beck, Sarah R.; Heald, Mary; Powis, Laurie; Oliver, Chris

2016-01-01

Working memory (WM) impairments might amplify behavioural difference in genetic syndromes. Murine models of Rubinstein-Taybi syndrome (RTS) evidence memory impairments but there is limited research on memory in RTS. Individuals with RTS and typically developing children completed WM tasks, with participants with RTS completing an IQ assessment and…
Everyday memory impairment in patients with temporal lobe epilepsy caused by hippocampal sclerosis.

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Rzezak, Patrícia; Lima, Ellen Marise; Gargaro, Ana Carolina; Coimbra, Erica; de Vincentiis, Silvia; Velasco, Tonicarlo Rodrigues; Leite, João Pereira; Busatto, Geraldo F; Valente, Kette D

2017-04-01

Patients with temporal lobe epilepsy caused by hippocampal sclerosis (TLE-HS) have episodic memory impairment. Memory has rarely been evaluated using an ecologic measure, even though performance on these tests is more related to patients' memory complaints. We aimed to measure everyday memory of patients with TLE-HS to age- and gender-matched controls. We evaluated 31 patients with TLE-HS and 34 healthy controls, without epilepsy and psychiatric disorders, using the Rivermead Behavioral Memory Test (RBMT), Visual Reproduction (WMS-III) and Logical Memory (WMS-III). We evaluated the impact of clinical variables such as the age of onset, epilepsy duration, AED use, history of status epilepticus, and seizure frequency on everyday memory. Statistical analyses were performed using MANCOVA with years of education as a confounding factor. Patients showed worse performance than controls on traditional memory tests and in the overall score of RBMT. Patients had more difficulties to recall names, a hidden belonging, to deliver a message, object recognition, to remember a story full of details, a previously presented short route, and in time and space orientation. Clinical epilepsy variables were not associated with RBMT performance. Memory span and working memory were correlated with worse performance on RBMT. Patients with TLE-HS demonstrated deficits in everyday memory functions. A standard neuropsychological battery, designed to assess episodic memory, would not evaluate these impairments. Impairment in recalling names, routes, stories, messages, and space/time disorientation can adversely impact social adaptation, and we must consider these ecologic measures with greater attention in the neuropsychological evaluation of patients with memory complaints. Copyright © 2017 Elsevier Inc. All rights reserved.
Toxin-Induced Experimental Models of Learning and Memory Impairment.

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More, Sandeep Vasant; Kumar, Hemant; Cho, Duk-Yeon; Yun, Yo-Sep; Choi, Dong-Kug

2016-09-01

Animal models for learning and memory have significantly contributed to novel strategies for drug development and hence are an imperative part in the assessment of therapeutics. Learning and memory involve different stages including acquisition, consolidation, and retrieval and each stage can be characterized using specific toxin. Recent studies have postulated the molecular basis of these processes and have also demonstrated many signaling molecules that are involved in several stages of memory. Most insights into learning and memory impairment and to develop a novel compound stems from the investigations performed in experimental models, especially those produced by neurotoxins models. Several toxins have been utilized based on their mechanism of action for learning and memory impairment such as scopolamine, streptozotocin, quinolinic acid, and domoic acid. Further, some toxins like 6-hydroxy dopamine (6-OHDA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and amyloid-β are known to cause specific learning and memory impairment which imitate the disease pathology of Parkinson's disease dementia and Alzheimer's disease dementia. Apart from these toxins, several other toxins come under a miscellaneous category like an environmental pollutant, snake venoms, botulinum, and lipopolysaccharide. This review will focus on the various classes of neurotoxin models for learning and memory impairment with their specific mechanism of action that could assist the process of drug discovery and development for dementia and cognitive disorders.
Histone deacetylase inhibition abolishes stress-induced spatial memory impairment.

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Vargas-López, Viviana; Lamprea, Marisol R; Múnera, Alejandro

2016-10-01

Acute stress induced before spatial training impairs memory consolidation. Although non-epigenetic underpinning of such effect has been described, the epigenetic mechanisms involved have not yet been studied. Since spatial training and intense stress have opposite effects on histone acetylation balance, it is conceivable that disruption of such balance may underlie acute stress-induced spatial memory consolidation impairment and that inhibiting histone deacetylases prevents such effect. Trichostatin-A (TSA, a histone deacetylase inhibitor) was used to test its effectiveness in preventing stress' deleterious effect on memory. Male Wistar rats were trained in a spatial task in the Barnes maze; 1-h movement restraint was applied to half of them before training. Immediately after training, stressed and non-stressed animals were randomly assigned to receive either TSA (1mg/kg) or vehicle intraperitoneal injection. Twenty-four hours after training, long-term spatial memory was tested; plasma and brain tissue were collected immediately after the memory test to evaluate corticosterone levels and histone H3 acetylation in several brain areas. Stressed animals receiving vehicle displayed memory impairment, increased plasma corticosterone levels and markedly reduced histone H3 acetylation in prelimbic cortex and hippocampus. Such effects did not occur in stressed animals treated with TSA. The aforementioned results support the hypothesis that acute stress induced-memory impairment is related to histone deacetylation. Copyright © 2016 Elsevier Inc. All rights reserved.
Dehydroepiandrosterone impacts working memory by shaping cortico-hippocampal structural covariance during development.

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Nguyen, Tuong-Vi; Wu, Mia; Lew, Jimin; Albaugh, Matthew D; Botteron, Kelly N; Hudziak, James J; Fonov, Vladimir S; Collins, D Louis; Campbell, Benjamin C; Booij, Linda; Herba, Catherine; Monnier, Patricia; Ducharme, Simon; McCracken, James T

2017-12-01

Existing studies suggest that dehydroepiandrosterone (DHEA) may be important for human brain development and cognition. For example, molecular studies have hinted at the critical role of DHEA in enhancing brain plasticity. Studies of human brain development also support the notion that DHEA is involved in preserving cortical plasticity. Further, some, though not all, studies show that DHEA administration may lead to improvements in working memory in adults. Yet these findings remain limited by an incomplete understanding of the specific neuroanatomical mechanisms through which DHEA may impact the CNS during development. Here we examined associations between DHEA, cortico-hippocampal structural covariance, and working memory (216 participants [female=123], age range 6-22 years old, mean age: 13.6 +/-3.6 years, each followed for a maximum of 3 visits over the course of 4 years). In addition to administering performance-based, spatial working memory tests to these children, we also collected ecological, parent ratings of working memory in everyday situations. We found that increasingly higher DHEA levels were associated with a shift toward positive insular-hippocampal and occipito-hippocampal structural covariance. In turn, DHEA-related insular-hippocampal covariance was associated with lower spatial working memory but higher overall working memory as measured by the ecological parent ratings. Taken together with previous research, these results support the hypothesis that DHEA may optimize cortical functions related to general attentional and working memory processes, but impair the development of bottom-up, hippocampal-to-cortical connections, resulting in impaired encoding of spatial cues. Copyright © 2017 Elsevier Ltd. All rights reserved.
Suppressing Irrelevant Information from Working Memory: Evidence for Domain-Specific Deficits in Poor Comprehenders

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Pimperton, Hannah; Nation, Kate

2010-01-01

Previous research has suggested that children with specific reading comprehension deficits (poor comprehenders) show an impaired ability to suppress irrelevant information from working memory, with this deficit detrimentally impacting on their working memory ability, and consequently limiting their reading comprehension performance. However, the…
Frontal Structural Neural Correlates of Working Memory Performance in Older Adults.

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Nissim, Nicole R; O'Shea, Andrew M; Bryant, Vaughn; Porges, Eric C; Cohen, Ronald; Woods, Adam J

2016-01-01

Working memory is an executive memory process that allows transitional information to be held and manipulated temporarily in memory stores before being forgotten or encoded into long-term memory. Working memory is necessary for everyday decision-making and problem solving, making it a fundamental process in the daily lives of older adults. Working memory relies heavily on frontal lobe structures and is known to decline with age. The current study aimed to determine the neural correlates of decreased working memory performance in the frontal lobes by comparing cortical thickness and cortical surface area from two demographically matched groups of healthy older adults, free from cognitive impairment, with high versus low N-Back working memory performance ( N = 56; average age = 70.29 ± 10.64). High-resolution structural T1-weighted images (1 mm isotropic voxels) were obtained on a 3T Philips MRI scanner. When compared to high performers, low performers exhibited significantly decreased cortical surface area in three frontal lobe regions lateralized to the right hemisphere: medial orbital frontal gyrus, inferior frontal gyrus, and superior frontal gyrus (FDR p frontal regions may underlie age-related decline of working memory function.
Retrieval deficiency in brain activity of working memory in amnesic mild cognitive impairment patients: A brain event-related potentials study

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Binyin eLi

2016-03-01

Full Text Available In the early stage of Alzheimer disease (AD or mild cognitive impairment (MCI, working memory (WM deficiency is prominent and could be attributed to failure in encoding, maintenance or retrieval of information. However, evidence for a retention or retrieval deficit remains equivocal. It is also unclear what cognitive mechanism in working memory is impaired in MCI or early AD. We enrolled forty-six subjects from our Memory Clinics and community, with 24 amnesic MCI patients and 22 normal subjects. After neurological and cognitive assessments, they performed a classic delayed match to sample task with simultaneous event-related potential (ERP recorded. The ERPs in encoding and retrieval epoch during WM were analyzed separately. The latency and amplitude of every ERP component were compared between two groups, and then analyzed to explore their relationship with neuropsychological performance. Finally, the locations of maximal difference in cortex were calculated by standard low-resolution tomographic analysis. A total of five components were found: P1, N1, P2, N2 and P300. The amplitude of P2 and P300 was larger in normal subjects than in MCI patients only during retrieval, not encoding epoch, while the latency did not show statistical difference. The latency and amplitude of P1 and N1 were similar in two groups. P2 amplitude in the retrieval epoch positively correlated with memory test (auditory verbal learning test and visual spatial score of Chinese Addenbrooke’s Cognitive Examination-Revised (ACE-R, while P300 amplitude correlated with ACE-R. The activation difference in P2 time range was maximal at medial frontal gyrus. However, the difference in cortex activation during P300 time range did not show significance. The amplitude of P2 indicated deficiency in memory retrieval process, potentially due to dysfunction of central executive in WM model. Regarding the location of P2 during WM task, medial frontal plays important role in memory
Sleep deprivation specifically impairs short-term olfactory memory in Drosophila.

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Li, Xinjian; Yu, Feng; Guo, Aike

2009-11-01

Sleep is crucial to memory consolidation in humans and other animals; however, the effect of insufficient sleep on subsequent learning and memory remains largely elusive. Learning and memory after 1-day sleep deprivation (slpD) was evaluated using Pavlovian olfactory conditioning in Drosophila, and locomotor activity was measured using the Drosophila Activity Monitoring System in a 12:12 light-dark cycle. We found that slpD specifically impaired 1-h memory in wild type Canton-S flies, and this effect could persist for at least 2 h. However, alternative stresses (heat stress, oxidative stress, starvation, and rotation stress) did not result in a similar effect and left the flies' memory intact. Mechanistic studies demonstrated that flies with either silenced transmission of the mushroom body (MB) during slpD or down-regulated cAMP levels in the MB demonstrated no slpD-induced 1-h memory impairment. We found that slpD specifically impaired 1-h memory in Drosophila, and either silencing of MB transmission during slpD or down-regulation of the cAMP level in the MB protected the flies from slpD-induced impairment.
Detection of memory impairment among community-dwelling elderly by using the Rivermead Behavioural Memory Test

International Nuclear Information System (INIS)

Shinagawa, Shunichiro; Toyota, Yasutaka; Matsumoto, Teruhisa; Sonobe, Naomi; Adachi, Hiroyoshi; Mori, Takaaki; Ishikawa, Tomohisa; Fukuhara, Ryuji; Ikeda, Manabu

2010-01-01

The aim of this study was to use the Rivermead Behavioural Memory Test (RBMT) to evaluate everyday memory impairment among community-dwelling elderly who had normal cognitive function and performed daily activities normally but displayed memory impairments, and to diagnose the condition as either mild cognitive impairment or dementia. Among the 1,290 community-dwelling elderly persons who participated in the study, 72 subjects scored higher than 24 on the Mini-Mental State Examination (MMSE): these subjects performed daily activities normally, but their family members reported that they showed memory impairments. Fifty-two subjects completed RBMT, Clinical Dementia Rating, and brain computed tomography, and a final diagnosis was established. The mean standard profile score was 15.1±5.0 and mean screening score was 6.4±3.0. RBMT score was correlated with the MMSE score. Nine of the subjects were diagnosed with dementia and 26 of them were found to be normal. RBMT achieved 100% sensitivity and specificity with regard to the differentiation of subjects with Alzheimer's disease. However, some subjects were diagnosed with dementia even though their RBMT score was higher than the cut-off score. RBMT was useful in detecting memory impairments of Alzheimer's disease (AD) subjects in community-based surveys. However, some subjects were diagnosed with dementia because of the existence of other cognitive impairments among community-dwelling elderly. (author)
Is the frontal dysexecutive syndrome due to a working memory deficit? Evidence from patients with stroke.

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Roussel, Martine; Dujardin, Kathy; Hénon, Hilde; Godefroy, Olivier

2012-07-01

Although frontal dysexecutive disorders are frequently considered to be due to working memory deficit, this has not been systematically examined and very little evidence is available for impairment of working memory in frontal damage. The objective of this study was to examine the components of working memory, their anatomy and the relations with executive functions in patients with stroke involving the frontal or posterior cortex. The study population consisted of 29 patients (frontal: n=17; posterior: n=12) and 29 matched controls. Phonological loop (letter and word spans, phonological store; rehearsal process), visuospatial sketchpad (visuospatial span) and the central executive (working memory span, dual task and updating process) were examined. The group comparison analysis showed impairment in the frontal group of: (i) verbal spans (Pdeficit of the rehearsal process (P=0.006); (iii) visuospatial span (P=0.04); (iv) working memory span (P=0.001) that disappeared after controlling for verbal span and (v) running memory (P=0.05) unrelated to updating conditions. The clinical anatomical correlation study showed that impairment of the central executive depended on frontal and posterior lesion. Cognitive dysexecutive disorders were observed in 11/20 patients with central executive deficit and an inverse dissociation was observed in two patients. Receiver operating characteristic curve analysis indicated that cognitive dysexecutive disorders had the highest ability to discriminate frontal lesions (area under curve=0.844, 95% confidence interval: 0.74-0.95; P=0.0001; central executive impairment: area under curve=0.732, 95% confidence interval: 0.57-0.82; P=0.006). This study reveals that frontal lesions induce mild impairment of short-term memory associated with a deficit of the rehearsal process supporting the role of the frontal lobe in this process; the central executive depends on lesions in the frontal lobe and posterior regions accounting for its low frequency

Working memory for conjunctions relies on the medial temporal lobe.

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Olson, Ingrid R; Page, Katie; Moore, Katherine Sledge; Chatterjee, Anjan; Verfaellie, Mieke

2006-04-26

A prominent theory of hippocampal function proposes that the hippocampus is importantly involved in relating or binding together separate pieces of information to form an episodic representation. This hypothesis has only been applied to studies of long-term memory because the paradigmatic view of the hippocampus is that it is not critical for short-term forms of memory. However, relational processing is important in many working memory tasks, especially tasks using visual stimuli. Here, we test the hypothesis that the medial temporal lobes are important for relational memory even over short delays. The task required patients with medial temporal lobe amnesia and controls to remember three objects, locations, or object-location conjunctions over 1 or 8 s delays. The results show that working memory for objects and locations was at normal levels, but that memory for conjunctions was severely impaired at 8 s delays. Additional analyses suggest that the hippocampus per se is critical for accurate conjunction working memory. We propose that the hippocampus is critically involved in memory for conjunctions at both short and long delays.
Gummed-up memory: chewing gum impairs short-term recall.

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Kozlov, Michail D; Hughes, Robert W; Jones, Dylan M

2012-01-01

Several studies have suggested that short-term memory is generally improved by chewing gum. However, we report the first studies to show that chewing gum impairs short-term memory for both item order and item identity. Experiment 1 showed that chewing gum reduces serial recall of letter lists. Experiment 2 indicated that chewing does not simply disrupt vocal-articulatory planning required for order retention: Chewing equally impairs a matched task that required retention of list item identity. Experiment 3 demonstrated that manual tapping produces a similar pattern of impairment to that of chewing gum. These results clearly qualify the assertion that chewing gum improves short-term memory. They also pose a problem for short-term memory theories asserting that forgetting is based on domain-specific interference given that chewing does not interfere with verbal memory any more than tapping. It is suggested that tapping and chewing reduce the general capacity to process sequences.
Infliximab ameliorates AD-associated object recognition memory impairment.

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Kim, Dong Hyun; Choi, Seong-Min; Jho, Jihoon; Park, Man-Seok; Kang, Jisu; Park, Se Jin; Ryu, Jong Hoon; Jo, Jihoon; Kim, Hyun Hee; Kim, Byeong C

2016-09-15

Dysfunctions in the perirhinal cortex (PRh) are associated with visual recognition memory deficit, which is frequently detected in the early stage of Alzheimer's disease. Muscarinic acetylcholine receptor-dependent long-term depression (mAChR-LTD) of synaptic transmission is known as a key pathway in eliciting this type of memory, and Tg2576 mice expressing enhanced levels of Aβ oligomers are found to have impaired mAChR-LTD in this brain area at as early as 3 months of age. We found that the administration of Aβ oligomers in young normal mice also induced visual recognition memory impairment and perturbed mAChR-LTD in mouse PRh slices. In addition, when mice were treated with infliximab, a monoclonal antibody against TNF-α, visual recognition memory impaired by pre-administered Aβ oligomers dramatically improved and the detrimental Aβ effect on mAChR-LTD was annulled. Taken together, these findings suggest that Aβ-induced inflammation is mediated through TNF-α signaling cascades, disturbing synaptic transmission in the PRh, and leading to visual recognition memory deficits. Copyright © 2016 Elsevier B.V. All rights reserved.
Can we improve the clinical assessment of working memory? An evaluation of the Wechsler Adult Intelligence Scale-Third Edition using a working memory criterion construct.

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Hill, B D; Elliott, Emily M; Shelton, Jill T; Pella, Russell D; O'Jile, Judith R; Gouvier, W Drew

2010-03-01

Working memory is the cognitive ability to hold a discrete amount of information in mind in an accessible state for utilization in mental tasks. This cognitive ability is impaired in many clinical populations typically assessed by clinical neuropsychologists. Recently, there have been a number of theoretical shifts in the way that working memory is conceptualized and assessed in the experimental literature. This study sought to determine to what extent the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) Working Memory Index (WMI) measures the construct studied in the cognitive working memory literature, whether an improved WMI could be derived from the subtests that comprise the WAIS-III, and what percentage of variance in individual WAIS-III subtests is explained by working memory. It was hypothesized that subtests beyond those currently used to form the WAIS-III WMI would be able to account for a greater percentage of variance in a working memory criterion construct than the current WMI. Multiple regression analyses (n = 180) revealed that the best predictor model of subtests for assessing working memory was composed of the Digit Span, Letter-Number Sequencing, Matrix Reasoning, and Vocabulary. The Arithmetic subtest was not a significant contributor to the model. These results are discussed in the context of how they relate to Unsworth and Engle's (2006, 2007) new conceptualization of working memory mechanisms.
INTERACTIONS BETWEEN WORKING MEMORY AND CREATIVITY: A SYSTEMATIC REVIEW

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Taís Crema Remoli

2017-03-01

Full Text Available Creativity and working memory are academic and professional success markers. Paradoxically, correlational studies do not always find associations between these constructs; some studies show positive associations between them and others show negative associations. Probably, the contradictory findings arise from different parameters, because of that it is important to identify them in order to have a more coherent understanding of this relationship. Thus, this systematic literature review aimed to answer the questions: “What is the relationship between working memory and creativity? Do update and serial recall mnemonic processes also interfere in the production of convergent or divergent thinking?” For this purpose, a survey of specific descriptors generated 384 articles found in Scopus, Web of Science and Pubmed databases, from which fifteen studies were selected. Despite the methodological variability between the selected studies, the results found suggest associations between working memory and creativity, which are explained by the attentional, inhibitory, analytical and motivational processes involved. A systematic review of these studies concluded that the characteristics of experimental tasks to study creativity and working memory used can influence the results of this association. It is also possible to infer that working memory overload can impair creative performance.
Understanding the role of mind wandering in stress-related working memory impairments.

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Banks, Jonathan B; Boals, Adriel

2017-08-01

Mind wandering has been identified as a possible cause for stress-related working memory (WM) task impairments following laboratory stressors. The current study attempted to induce mind wandering regarding negative, positive, or neutral events using an expressive writing task and examined the impact on WM task performance. We examined the role of mind wandering in understanding the impact of life stress on WM. Additionally, we explored the role of thought suppression on the relationship between mind wandering and WM. One hundred and fifty participants completed WM measures before (Time 1) and after (Time 2) the writing manipulation. The writing manipulation did not alter mind wandering or WM task performance. Time 1 WM predicted mind wandering during the Time 2 WM task, which subsequently predicted poorer Time 2 WM task performance. The impact of daily life stress on WM was mediated by mind wandering. Trait levels of thought suppression moderated the impact of mind wandering on WM. Specifically, higher levels of suppression resulted in stronger negative impact of mind wandering on WM task performance. Findings are discussed in terms of the impact of mind wandering on WM task performance.
Neutral and emotional episodic memory: global impairment after lorazepam or scopolamine.

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Kamboj, Sunjeev K; Curran, H Valerie

2006-11-01

Benzodiazepines and anticholinergic drugs have repeatedly been shown to impair episodic memory for emotionally neutral material in humans. However, their effect on memory for emotionally laden stimuli has been relatively neglected. We sought to investigate the effects of the benzodiazepine, lorazepam, and the anticholinergic, scopolamine, on incidental episodic memory for neutral and emotional components of a narrative memory task in humans. A double-blind, placebo-controlled independent group design was used with 48 healthy volunteers to examine the effects of these drugs on emotional and neutral episodic memory. As expected, the emotional memory advantage was retained for recall and recognition memory under placebo conditions. However, lorazepam and scopolamine produced anterograde recognition memory impairments on both the neutral and emotional components of the narrative, although floor effects were obtained for recall memory. Furthermore, compared with placebo, recognition memory for both central (gist) and peripheral (detail) aspects of neutral and emotional elements of the narrative was poorer after either drug. Benzodiazepine-induced GABAergic enhancement or scopolamine-induced cholinergic hypofunction results in a loss of the enhancing effect of emotional arousal on memory. Furthermore, lorazepam- and scopolamine-induced memory impairment for both gist (which is amygdala dependent) and detail raises the possibility that their effects on emotional memory do not depend only on the amygdala. We discuss the results with reference to potential clinical/forensic implications of processing emotional memories under conditions of globally impaired episodic memory.
Hippocampal damage equally impairs memory for single items and memory for conjunctions.

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Stark, Craig E L; Squire, Larry R

2003-01-01

In a prior study of continuous recognition performance, data were reported in support of the hypothesis that the hippocampus is not needed to remember the individual components of a stimulus but is important for remembering associations between its components (Kroll et al. 1996. J Mem Lang 35:176-196). Patients with left hippocampal damage were able to endorse recently encountered words and to reject novel words, as well as disyllabic words in which one of the syllables had been previously encountered. However, they failed to reject words in which both syllables had been encountered independently in different words. We present data from five experiments designed to examine this finding in more detail. In each experiment, five patients with bilateral hippocampal damage and eight controls were tested using the same protocol as Kroll et al. (1996). On each trial, a two-component stimulus was presented. Stimuli could be entirely novel, novel with one previously encountered (repeated) component, novel but with both components repeated, or a true repetition. The first experiment was a direct replication using the same disyllabic words as Kroll et al. (1996). The second experiment used pseudo-words, constructed of two monosyllabic words (e.g., jambark). The third experiment used the same pairs of monosyllabic words, but presented separately on the screen to encourage participants to treat each component independently. The fourth experiment used pairs of objects, and the fifth experiment used face-house pairs. In all five experiments, patients with hippocampal damage exhibited impaired recognition memory. The impairment extended across all trial types with no evidence that hippocampal damage selectively (or disproportionately) impaired the associative or conjunctive component of memory. We discuss our findings in the light of the work by Kroll et al. (1996) and other recent neuropsychological, electrophysiological, and neuroimaging studies of hippocampal function and
Frontal Cognitive Function and Memory in Parkinson’s Disease: Toward a Distinction between Prospective and Declarative Memory Impairments?

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A. I. Tröster

1995-01-01

Full Text Available Memory dysfunction is a frequent concomitant of Parkinson's disease (PD. Historically, two classes of hypotheses, focusing on different cognitive mechanisms, have been advanced to explain this memory impairment: one postulating retrieval deficits (common to several neurodegenerative disorders involving the basal ganglia, and the other postulating frontally mediated executive deficits as fundamental to memory impairment. After outlining empirical support for the retrieval deficit hypothesis, research on the more recent “frontal executive deficit hypothesis” is reviewed, and major challenges to this hypothesis are identified. It is concluded that the frontal executive deficit hypothesis cannot adequately account for all memory impairments in PD, and that a more parsimonious theoretical account might invoke a distinction between prospective and declarative memory impairments. It is suggested that there may be three subgroups of PD patients: one demonstrating prospective memory dysfunction only, one with declarative memory dysfunction only, and one with both prospective and declarative memory dysfunction. Consequently, PD might provide a useful model within which to investigate the relationship between prospective and declarative memory.
Caffeine cravings impair memory and metacognition.

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Palmer, Matthew A; Sauer, James D; Ling, Angus; Riza, Joshua

2017-10-01

Cravings for food and other substances can impair cognition. We extended previous research by testing the effects of caffeine cravings on cued-recall and recognition memory tasks, and on the accuracy of judgements of learning (JOLs; predicted future recall) and feeling-of-knowing (FOK; predicted future recognition for items that cannot be recalled). Participants (N = 55) studied word pairs (POND-BOOK) and completed a cued-recall test and a recognition test. Participants made JOLs prior to the cued-recall test and FOK judgements prior to the recognition test. Participants were randomly allocated to a craving or control condition; we manipulated caffeine cravings via a combination of abstinence, cue exposure, and imagery. Cravings impaired memory performance on the cued-recall and recognition tasks. Cravings also impaired resolution (the ability to distinguish items that would be remembered from those that would not) for FOK judgements but not JOLs, and reduced calibration (correspondence between predicted and actual accuracy) for JOLs but not FOK judgements. Additional analysis of the cued-recall data suggested that cravings also reduced participants' ability to monitor the likely accuracy of answers during the cued-recall test. These findings add to prior research demonstrating that memory strength manipulations have systematically different effects on different types of metacognitive judgements.
A facilitative effect of negative affective valence on working memory.

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Gotoh, Fumiko; Kikuchi, Tadashi; Olofsson, Ulrich

2010-06-01

Previous studies have shown that negatively valenced information impaired working memory performance due to an attention-capturing effect. The present study examined whether negative valence could also facilitate working memory. Affective words (negative, neutral, positive) were used as retro-cues in a working memory task that required participants to remember colors at different spatial locations on a computer screen. Following the cue, a target detection task was used to either shift attention to a different location or keep attention at the same location as the retro-cue. Finally, participants were required to discriminate the cued color from a set of distractors. It was found that negative cues yielded shorter response times (RTs) in the attention-shift condition and longer RTs in the attention-stay condition, compared with neutral and positive cues. The results suggest that negative affective valence may enhance working memory performance (RTs), provided that attention can be disengaged.
Proinflammatory Factors Mediate Paclitaxel-Induced Impairment of Learning and Memory

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Zhao Li

2018-01-01

Full Text Available The chemotherapeutic agent paclitaxel is widely used for cancer treatment. Paclitaxel treatment impairs learning and memory function, a side effect that reduces the quality of life of cancer survivors. However, the neural mechanisms underlying paclitaxel-induced impairment of learning and memory remain unclear. Paclitaxel treatment leads to proinflammatory factor release and neuronal apoptosis. Thus, we hypothesized that paclitaxel impairs learning and memory function through proinflammatory factor-induced neuronal apoptosis. Neuronal apoptosis was assessed by TUNEL assay in the hippocampus. Protein expression levels of tumor necrosis factor-α (TNF-α and interleukin-1β (IL-1β in the hippocampus tissue were analyzed by Western blot assay. Spatial learning and memory function were determined by using the Morris water maze (MWM test. Paclitaxel treatment significantly increased the escape latencies and decreased the number of crossing in the MWM test. Furthermore, paclitaxel significantly increased the number of TUNEL-positive neurons in the hippocampus. Also, paclitaxel treatment increased the expression levels of TNF-α and IL-1β in the hippocampus tissue. In addition, the TNF-α synthesis inhibitor thalidomide significantly attenuated the number of paclitaxel-induced TUNEL-positive neurons in the hippocampus and restored the impaired spatial learning and memory function in paclitaxel-treated rats. These data suggest that TNF-α is critically involved in the paclitaxel-induced impairment of learning and memory function.
Memory impairment among people who are homeless: a systematic review.

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Ennis, Naomi; Roy, Sylvain; Topolovec-Vranic, Jane

2015-01-01

Cognitive impairment may interfere with an individual's ability to function independently in the community and may increase the risk of becoming and remaining homeless. The purpose of this study was to systematically review the literature on memory deficits among people who are homeless in order to gain a better understanding of its nature, causes and prevalence. Studies that measured memory functioning as an outcome among a sample of homeless persons were included. Data on sampling, outcome measures, facet of memory explored and prevalence of memory impairment were extracted from all selected research studies. Included studies were evaluated using a critical appraisal process targetted for reviewing prevalence studies. Eleven studies were included in the review. Verbal memory was the most commonly studied facet of memory. Potential contributing factors to memory deficits among persons who are homeless were explored in seven studies. Memory deficits were common among the samples of homeless persons studied. However, there was a great deal of variation in the methodology and quality of the included studies. Conceptualisations of "homelessness" also differed across studies. There is a need for more controlled research using validated neuropsychological tools to evaluate memory impairment among people who are homeless.
Memory for Items and Relationships among Items Embedded in Realistic Scenes: Disproportionate Relational Memory Impairments in Amnesia

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Hannula, Deborah E.; Tranel, Daniel; Allen, John S.; Kirchhoff, Brenda A.; Nickel, Allison E.; Cohen, Neal J.

2014-01-01

Objective The objective of this study was to examine the dependence of item memory and relational memory on medial temporal lobe (MTL) structures. Patients with amnesia, who either had extensive MTL damage or damage that was relatively restricted to the hippocampus, were tested, as was a matched comparison group. Disproportionate relational memory impairments were predicted for both patient groups, and those with extensive MTL damage were also expected to have impaired item memory. Method Participants studied scenes, and were tested with interleaved two-alternative forced-choice probe trials. Probe trials were either presented immediately after the corresponding study trial (lag 1), five trials later (lag 5), or nine trials later (lag 9) and consisted of the studied scene along with a manipulated version of that scene in which one item was replaced with a different exemplar (item memory test) or was moved to a new location (relational memory test). Participants were to identify the exact match of the studied scene. Results As predicted, patients were disproportionately impaired on the test of relational memory. Item memory performance was marginally poorer among patients with extensive MTL damage, but both groups were impaired relative to matched comparison participants. Impaired performance was evident at all lags, including the shortest possible lag (lag 1). Conclusions The results are consistent with the proposed role of the hippocampus in relational memory binding and representation, even at short delays, and suggest that the hippocampus may also contribute to successful item memory when items are embedded in complex scenes. PMID:25068665
Stress-induced deficits in working memory and visuo-constructive abilities in Special Operations soldiers.

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Morgan, Charles A; Doran, Anthony; Steffian, George; Hazlett, Gary; Southwick, Steven M

2006-10-01

Pre-clinical and clinical studies have shown acute stress may impair working memory and visuo-spatial ability. This study was designed to clarify the nature of stress-induced cognitive deficits in soldiers and how such deficits may contribute to operational or battlefield errors. One hundred eighty-four Special Operations warfighters enrolled in Survival School completed pre-stress measures of dissociation and trauma exposure. Subjects were randomized to one of three assessment groups (Pre-stress, Stress, Post-stress) and were administered the Rey Ostereith Complex Figure (ROCF). All subjects completed post-stress measures of dissociation. ROCF copy and recall were normal in the Pre- and Post-stress groups. ROCF copy and recall were significantly impaired in the Stress Group. Stress group ROCF copy performance was piecemeal, and ROCF recall was impaired. Symptoms of dissociation were negatively associated with ROCF recall in the Stress group. Baseline dissociation and history of traumatic stress predicted cognitive impairment during stress. Stress exposure impaired visuo-spatial capacity and working memory. In rats, monkeys, and humans, high dopamine and NE turnover in the PFC induce deficits in cognition and spatial working memory. Improved understanding of stress-induced cognitive deficits may assist in identification of soldiers at risk and lead to the development of better countermeasures.
Artificial theta stimulation impairs encoding of contextual fear memory.

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Arto Lipponen

Full Text Available Several experiments have demonstrated an intimate relationship between hippocampal theta rhythm (4-12 Hz and memory. Lesioning the medial septum or fimbria-fornix, a fiber track connecting the hippocampus and the medial septum, abolishes the theta rhythm and results in a severe impairment in declarative memory. To assess whether there is a causal relationship between hippocampal theta and memory formation we investigated whether restoration of hippocampal theta by electrical stimulation during the encoding phase also restores fimbria-fornix lesion induced memory deficit in rats in the fear conditioning paradigm. Male Wistar rats underwent sham or fimbria-fornix lesion operation. Stimulation electrodes were implanted in the ventral hippocampal commissure and recording electrodes in the septal hippocampus. Artificial theta stimulation of 8 Hz was delivered during 3-min free exploration of the test cage in half of the rats before aversive conditioning with three foot shocks during 2 min. Memory was assessed by total freezing time in the same environment 24 h and 28 h after fear conditioning, and in an intervening test session in a different context. As expected, fimbria-fornix lesion impaired fear memory and dramatically attenuated hippocampal theta power. Artificial theta stimulation produced continuous theta oscillations that were almost similar to endogenous theta rhythm in amplitude and frequency. However, contrary to our predictions, artificial theta stimulation impaired conditioned fear response in both sham and fimbria-fornix lesioned animals. These data suggest that restoration of theta oscillation per se is not sufficient to support memory encoding after fimbria-fornix lesion and that universal theta oscillation in the hippocampus with a fixed frequency may actually impair memory.
Prefrontal cortex and mediodorsal thalamus reduced connectivity is associated with spatial working memory impairment in rats with inflammatory pain.

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Cardoso-Cruz, Helder; Sousa, Mafalda; Vieira, Joana B; Lima, Deolinda; Galhardo, Vasco

2013-11-01

The medial prefrontal cortex (mPFC) and the mediodorsal thalamus (MD) form interconnected neural circuits that are important for spatial cognition and memory, but it is not known whether the functional connectivity between these areas is affected by the onset of an animal model of inflammatory pain. To address this issue, we implanted 2 multichannel arrays of electrodes in the mPFC and MD of adult rats and recorded local field potential activity during a food-reinforced spatial working memory task. Recordings were performed for 3weeks, before and after the establishment of the pain model. Our results show that inflammatory pain caused an impairment of spatial working memory performance that is associated with changes in the activity of the mPFC-MD circuit; an analysis of partial directed coherence between the areas revealed a global decrease in the connectivity of the circuit. This decrease was observed over a wide frequency range in both the frontothalamic and thalamofrontal directions of the circuit, but was more evident from MD to mPFC. In addition, spectral analysis revealed significant oscillations of power across frequency bands, namely with a strong theta component that oscillated after the onset of the painful condition. Finally, our data revealed that chronic pain induces an increase in theta/gamma phase coherence and a higher level of mPFC-MD coherence, which is partially conserved across frequency bands. The present results demonstrate that functional disturbances in mPFC-MD connectivity are a relevant cause of deficits in pain-related working memory. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
Verbal Memory Impairment in Polydrug Ecstasy Users: A Clinical Perspective.

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Kim P C Kuypers

Full Text Available Ecstasy use has been associated with short-term and long-term memory deficits on a standard Word Learning Task (WLT. The clinical relevance of this has been debated and is currently unknown. The present study aimed at evaluating the clinical relevance of verbal memory impairment in Ecstasy users. To that end, clinical memory impairment was defined as decrement in memory performance that exceeded the cut-off value of 1.5 times the standard deviation of the average score in the healthy control sample. The primary question was whether being an Ecstasy user (E-user was predictive of having clinically deficient memory performance compared to a healthy control group.WLT data were pooled from four experimental MDMA studies that compared memory performance during placebo and MDMA intoxication. Control data were taken from healthy volunteers with no drug use history who completed the WLT as part of a placebo-controlled clinical trial. This resulted in a sample size of 65 E-users and 65 age- and gender-matched healthy drug-naïve controls. All participants were recruited by similar means and were tested at the same testing facilities using identical standard operating procedures. Data were analyzed using linear mixed-effects models, Bayes factor, and logistic regressions.Findings were that verbal memory performance of placebo-treated E-users did not differ from that of controls, and there was substantial evidence in favor of the null hypothesis. History of use was not predictive of memory impairment. During MDMA intoxication of E-users, verbal memory was impaired.The combination of the acute and long-term findings demonstrates that, while clinically relevant memory impairment is present during intoxication, it is absent during abstinence. This suggests that use of Ecstasy/MDMA does not lead to clinically deficient memory performance in the long term. Additionally, it has to be investigated whether the current findings apply to more complex cognitive
Verbal Memory Impairment in Polydrug Ecstasy Users: A Clinical Perspective.

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Kuypers, Kim P C; Theunissen, Eef L; van Wel, Janelle H P; de Sousa Fernandes Perna, Elizabeth B; Linssen, Anke; Sambeth, Anke; Schultz, Benjamin G; Ramaekers, Johannes G

2016-01-01

Ecstasy use has been associated with short-term and long-term memory deficits on a standard Word Learning Task (WLT). The clinical relevance of this has been debated and is currently unknown. The present study aimed at evaluating the clinical relevance of verbal memory impairment in Ecstasy users. To that end, clinical memory impairment was defined as decrement in memory performance that exceeded the cut-off value of 1.5 times the standard deviation of the average score in the healthy control sample. The primary question was whether being an Ecstasy user (E-user) was predictive of having clinically deficient memory performance compared to a healthy control group. WLT data were pooled from four experimental MDMA studies that compared memory performance during placebo and MDMA intoxication. Control data were taken from healthy volunteers with no drug use history who completed the WLT as part of a placebo-controlled clinical trial. This resulted in a sample size of 65 E-users and 65 age- and gender-matched healthy drug-naïve controls. All participants were recruited by similar means and were tested at the same testing facilities using identical standard operating procedures. Data were analyzed using linear mixed-effects models, Bayes factor, and logistic regressions. Findings were that verbal memory performance of placebo-treated E-users did not differ from that of controls, and there was substantial evidence in favor of the null hypothesis. History of use was not predictive of memory impairment. During MDMA intoxication of E-users, verbal memory was impaired. The combination of the acute and long-term findings demonstrates that, while clinically relevant memory impairment is present during intoxication, it is absent during abstinence. This suggests that use of Ecstasy/MDMA does not lead to clinically deficient memory performance in the long term. Additionally, it has to be investigated whether the current findings apply to more complex cognitive measures in diverse
Confabulation and memory impairments following frontal lobe lesions

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Turner, Martha

2005-01-01

Neuroimaging studies have provided considerable evidence for frontal lobe involvement in memory processing. Memory impairments arc also frequently reported in patients with frontal lobe lesions. However detailed anatomical localisation is rare, making integration of lesion and imaging findings difficult. An investigation of the functional and anatomical contributions of the frontal lobes to memory was conducted in 42 patients with frontal lobe lesions, examining memory processes identified in...

Low-level lead exposure effects on spatial reference memory and working memory in rats

Institute of Scientific and Technical Information of China (English)

Xinhua Yang; Ping Zhou; Yonghui Li

2009-01-01

BACKGROUND: Studies have demonstrated that lead exposure can result in cognitive dysfunction and behavior disorders. However, lead exposure impairments vary under different experimental conditions.OBJECTIVE: To detect changes in spatial learning and memory following low-level lead exposure in rats, in Morris water maze test under the same experimental condition used to analyze lead exposure effects on various memory types and learning processes.DESIGN AND SETTING: The experiment was conducted at the Animal Laboratory, Institute of Psychology, Chinese Academy of Science between February 2005 and March 2006. One-way analysis of variance (ANOVA) and behavioral observations were performed.MATERIALS: Sixteen male, healthy, adult, Sprague Dawley rats were randomized into normal control and lead exposure groups (n = 8).METHODS: Rats in the normal control group were fed distilled water, and those in the lead exposure group were fed 250 mL of 0.05% lead acetate once per day. At day 28, all rats performed the Morris water maze test, consisting of four phases: space navigation, probe test, working memory test, and visual cue test.MAIN OUTCOME MEASURES: Place navigation in the Morris water maze was used to evaluate spatial learning and memory, probe trials for spatial reference memory, working memory test for spatial working memory, and visual cue test for non-spatial cognitive function. Perkin-Elmer Model 300 Atomic Absorption Spectrometer was utilized to determine blood lead levels in rats.RESULTS: (1) In the working memory test, the time to reach the platform remained unchanged between the control and lead exposure groups (F(1,1) = 0.007, P = 0.935). A visible decrease in escape latencies was observed in each group (P = 0.028). However, there was no significant difference between the two groups (F(1,1) = 1.869, P = 0.193). The working memory probe test demonstrated no change between the two groups in the time spent in the target quadrant during the working memory probe test
Executive attention and working memory in narcoleptic outpatients

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Mirleny Moraes

2012-05-01

Full Text Available OBJECTIVE: This pioneering study aimed to evaluate executive attention and working memory in Brazilian narcoleptic outpatients. METHODS: Narcoleptic group: 19 treated narcoleptic outpatients (13 F; 6 M (mean age=37.58; SD = 8.93; control group: 19 subjects (15 F; 4 M (mean age=34.42; SD=12.31. INSTRUMENTS: Epworth Sleepiness Scale - Brazilian Portuguese Version (ESS-BR, Victoria Stroop Test (VST, Trail Making Test (TMT and Letter-Number Sequencing (LNS of WAIS-III. RESULTS: Significant difference at Excessive Daytime Sleepiness (EDS (p<0.001 and at working memory (p=0.009 with worse results for narcoleptic patients. Patients were slower at VST-1 (p=0.002, VST-2 (p=0.045 and at TMT-A (p=0.016, TMT-B (p=0.006 and B-A (p=0.024. CONCLUSION: Narcoleptic patients showed higher degrees of EDS, an impaired executive attention at a temporal level and lower performance in working memory when compared to normal controls.
Interaction between memory impairment and depressive symptoms can exacerbate anosognosia: a comparison of Alzheimer's disease with mild cognitive impairment.

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Oba, Hikaru; Matsuoka, Teruyuki; Imai, Ayu; Fujimoto, Hiroshi; Kato, Yuka; Shibata, Keisuke; Nakamura, Kaeko; Narumoto, Jin

2018-03-12

To investigate the effects of interactions between memory impairment, depressive symptoms, and anosognosia. Anosognosia for memory impairment was assessed in 118 patients with Alzheimer's disease (AD), 47 patients with mild cognitive impairment (MCI), and 17 non-diagnosed controls (NC) using a questionnaire and evaluation of the anosognosia score as the discrepancy between ratings of the patient and a relative. Demographic characteristics, such as the relationship of the patient with the relative and the activities of daily living (ADL) were evaluated. Memory impairment was evaluated with the Rivermead Behavioral Memory Test (RBMT), depressive symptoms were evaluated using the Geriatric Depression Scale (GDS) 15 items version. In the MCI group, a stepwise multiple regression analysis showed an interaction between RBMT and GDS scores, and simple slope analysis indicated that scores for RBMT at low GDS (-1 standard deviation) were positively correlated with self-rated memory impairment. In the AD group, the relationship of the patient with the relative, ADL, and GDS and RBMT scores were associated with the anosognosia score. Patients with MCI who have no depressive symptoms may be able to more accurately evaluate their memory impairment than those who have depressive symptoms and patients with AD. The evaluation by relatives, depressive symptoms or ADL of patients may distort evaluation of anosognosia for memory impairment in patients with AD or MCI. It seems necessary to include not only depression scale scores but also results of objective memory tests in the patients' medical information for the correct assessment of anosognosia.
Spatial working memory interferes with explicit, but not probabilistic cuing of spatial attention

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Won, Bo-Yeong; Jiang, Yuhong V.

2014-01-01

Recent empirical and theoretical work has depicted a close relationship between visual attention and visual working memory. For example, rehearsal in spatial working memory depends on spatial attention, whereas adding a secondary spatial working memory task impairs attentional deployment in visual search. These findings have led to the proposal that working memory is attention directed toward internal representations. Here we show that the close relationship between these two constructs is limited to some but not all forms of spatial attention. In five experiments, participants held color arrays, dot locations, or a sequence of dots in working memory. During the memory retention interval they performed a T-among-L visual search task. Crucially, the probable target location was cued either implicitly through location probability learning, or explicitly with a central arrow or verbal instruction. Our results showed that whereas imposing a visual working memory load diminished the effectiveness of explicit cuing, it did not interfere with probability cuing. We conclude that spatial working memory shares similar mechanisms with explicit, goal-driven attention but is dissociated from implicitly learned attention. PMID:25401460
Specific marker of feigned memory impairment: The activation of left superior frontal gyrus.

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Chen, Zi-Xiang; Xue, Li; Liang, Chun-Yu; Wang, Li-Li; Mei, Wei; Zhang, Qiang; Zhao, Hu

2015-11-01

Faking memory impairment means normal people complain lots of memory problems without organic damage in forensic assessments. Using alternative forced-choice paradigm, containing digital or autobiographical information, previous neuroimaging studies have indicated that faking memory impairment could cause the activation in the prefrontal and parietal regions, and might involve a fronto-parietal-subcortical circuit. However, it is still unclear whether different memory types have influence on faking or not. Since different memory types, such as long-term memory (LTM) and short-term memory (STM), were found supported by different brain areas, we hypothesized that feigned STM or LTM impairment had distinct neural activation mapping. Besides that, some common neural correlates may act as the general characteristic of feigned memory impairment. To verify this hypothesis, the functional magnetic resonance imaging (fMRI) combined with an alternative word forced-choice paradigm were used in this study. A total of 10 right-handed participants, in this study, had to perform both STW and LTM tasks respectively under answering correctly, answering randomly and feigned memory impairment conditions. Our results indicated that the activation of the left superior frontal gyrus and the left medial frontal gyrus was associated with feigned LTM impairment, whereas the left superior frontal gyrus, the left precuneus and the right anterior cingulate cortex (ACC) were highly activated while feigning STM impairment. Furthermore, an overlapping was found in the left superior frontal gyrus, and it suggested that the activity of the left superior frontal gyrus might be acting as a specific marker of feigned memory impairment. Copyright © 2015. Published by Elsevier Ltd.
The contribution of acetylcholine and dopamine to subprocesses of visual working memory--what patients with amnestic mild cognitive impairment and Parkinson׳s disease can tell us.

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Blatt, Joana; Vellage, Anne; Baier, Bernhard; Müller, Notger G

2014-08-01

Attentional selection, i.e. filtering out of irrelevant sensory input and information storage are two crucial components of working memory (WM). It has been proposed that the two processes are mediated by different neurotransmitters, namely acetylcholine for attentional selection and dopamine for memory storage. However, this hypothesis has been challenged by others, who for example linked a lack in dopamine levels in the brain to filtering deficits. Here we tested the above mentioned hypothesis in two patient cohorts which either served as a proxy for a cholinergic or a dopaminergic deficit. The first group comprised 18 patients with amnestic mild cognitive impairment (aMCI), the second 22 patients with Parkinson׳s disease (PD). The two groups did not differ regarding their overall cognitive abilities. Both patient groups as well as a control group without neurological deficits (n=25) performed a visuo-spatial working memory task in which both the necessity to filter out irrelevant information and memory load, i.e. the number of items to be held in memory, were manipulated. In accordance with the primary hypothesis, aMCI patients displayed problems with filtering, i.e., were especially impaired when the task required ignoring distracting stimuli. PD patients on the other hand showed difficulties when memory load was increased suggesting that they mainly suffered from a storage deficit. In sum, this study underlines how the investigation of neurologic patients with a presumed neurotransmitter deficit can aid to clarify these neurotransmitters׳ contribution to specific cognitive functions. Copyright © 2014 Elsevier Ltd. All rights reserved.
Competition between items in working memory leads to forgetting.

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Lewis-Peacock, Jarrod A; Norman, Kenneth A

2014-12-18

Switching attention from one thought to the next propels our mental lives forward. However, it is unclear how this thought-juggling affects our ability to remember these thoughts. Here we show that competition between the neural representations of pictures in working memory can impair subsequent recognition of those pictures. We use pattern classifiers to decode functional magnetic resonance imaging (fMRI) data from a retro-cueing task where participants juggle two pictures in working memory. Trial-by-trial fluctuations in neural dynamics are predictive of performance on a surprise recognition memory test: trials that elicit similar levels of classifier evidence for both pictures (indicating close competition) are associated with worse memory performance than trials where participants switch decisively from thinking about one picture to the other. This result is consistent with the non-monotonic plasticity hypothesis, which predicts that close competition can trigger weakening of memories that lose the competition, leading to subsequent forgetting.
The effect of acupuncture on mood and working memory in patients with depression and schizophrenia

NARCIS (Netherlands)

Bosch, M.P.C.; Noort, M.W.M.L. van den; Yeo, S.; Lim, S.; Coenen, A.M.L.; Luijtelaar, E.L.J.M. van

2015-01-01

BACKGROUND: In patients with depression, as well as in patients with schizophrenia, both mood and working memory performance are often impaired. Both issues can only be addressed and improved with medication to some extent. OBJECTIVE: This study investigates the mood and the working memory
Increased dopaminergic signaling impairs aversive olfactory memory retention in Drosophila.

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Zhang, Shixing; Yin, Yan; Lu, Huimin; Guo, Aike

2008-05-23

Dopamine is necessary for the aversive olfactory associative memory formation in Drosophila, but its effect on other stages of memory is not known. Herein, we studied the effect of enhanced dopaminergic signaling on aversive olfactory memory retention in flies. We used l-3,4-dihydroxyphenylalanine (l-DOPA) to elevate dopamine levels: l-DOPA-treated flies exhibited a normal learning performance, but a decrease in 1-h memory. Dopamine transporter (DAT) mutant flies or flies treated with the DAT inhibitor desipramine exhibited poor memory retention. Flies subjected to heat stress after training exhibited a decrease in memory. Memory was restored by blocking dopaminergic neuronal output during heat stress, suggesting that dopamine is involved in heat stress-induced memory impairment in flies. Taken together, our findings suggest that increased dopaminergic signaling impairs aversive olfactory memory retention in flies.
Protein Kinase A Deregulation in the Medial Prefrontal Cortex Impairs Working Memory in Murine Oligophrenin-1 Deficiency.

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Zhang, Chun-Lei; Aime, Mattia; Laheranne, Emilie; Houbaert, Xander; El Oussini, Hajer; Martin, Christelle; Lepleux, Marilyn; Normand, Elisabeth; Chelly, Jamel; Herzog, Etienne; Billuart, Pierre; Humeau, Yann

2017-11-15

Classical and systems genetics have identified wide networks of genes associated with cognitive and neurodevelopmental diseases. In parallel to deciphering the role of each of these genes in neuronal or synaptic function, evaluating the response of neuronal and molecular networks to gene loss of function could reveal some pathophysiological mechanisms potentially accessible to nongenetic therapies. Loss of function of the Rho-GAP oligophrenin-1 is associated with cognitive impairments in both human and mouse. Upregulation of both PKA and ROCK has been reported in Ophn1 -/ y mice, but it remains unclear whether kinase hyperactivity contributes to the behavioral phenotypes. In this study, we thoroughly characterized a prominent perseveration phenotype displayed by Ophn1 -deficient mice using a Y-maze spatial working memory (SWM) test. We report that Ophn1 deficiency in the mouse generated severe cognitive impairments, characterized by both a high occurrence of perseverative behaviors and a lack of deliberation during the SWM test. In vivo and in vitro pharmacological experiments suggest that PKA dysregulation in the mPFC underlies cognitive dysfunction in Ophn1 -deficient mice, as assessed using a delayed spatial alternation task results. Functionally, mPFC neuronal networks appeared to be affected in a PKA-dependent manner, whereas hippocampal-PFC projections involved in SWM were not affected in Ophn1 -/y mice. Thus, we propose that discrete gene mutations in intellectual disability might generate "secondary" pathophysiological mechanisms, which are prone to become pharmacological targets for curative strategies in adult patients. SIGNIFICANCE STATEMENT Here we report that Ophn1 deficiency generates severe impairments in performance at spatial working memory tests, characterized by a high occurrence of perseverative behaviors and a lack of decision making. This cognitive deficit is consecutive to PKA deregulation in the mPFC that prevents Ophn1 KO mice to exploit a
Recognition Memory Is Impaired in Children after Prolonged Febrile Seizures

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Martinos, Marina M.; Yoong, Michael; Patil, Shekhar; Chin, Richard F. M.; Neville, Brian G.; Scott, Rod C.; de Haan, Michelle

2012-01-01

Children with a history of a prolonged febrile seizure show signs of acute hippocampal injury on magnetic resonance imaging. In addition, animal studies have shown that adult rats who suffered febrile seizures during development reveal memory impairments. Together, these lines of evidence suggest that memory impairments related to hippocampal…
Cortical Thickness and Episodic Memory Impairment in Systemic Lupus Erythematosus.

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Bizzo, Bernardo Canedo; Sanchez, Tiago Arruda; Tukamoto, Gustavo; Zimmermann, Nicolle; Netto, Tania Maria; Gasparetto, Emerson Leandro

2017-01-01

The purpose of this study was to investigate differences in brain cortical thickness of systemic lupus erythematosus (SLE) patients with and without episodic memory impairment and healthy controls. We studied 51 patients divided in 2 groups (SLE with episodic memory deficit, n = 17; SLE without episodic memory deficit, n = 34) by the Rey Auditory Verbal Learning Test and 34 healthy controls. Groups were paired based on sex, age, education, Mini-Mental State Examination score, and accumulation of disease burden. Cortical thickness from magnetic resonance imaging scans was determined using the FreeSurfer software package. SLE patients with episodic memory deficits presented reduced cortical thickness in the left supramarginal cortex and superior temporal gyrus when compared to the control group and in the right superior frontal, caudal, and rostral middle frontal and precentral gyri when compared to the SLE group without episodic memory impairment considering time since diagnosis of SLE as covaried. There were no significant differences in the cortical thickness between the SLE without episodic memory and control groups. Different memory-related cortical regions thinning were found in the episodic memory deficit group when individually compared to the groups of patients without memory impairment and healthy controls. Copyright © 2016 by the American Society of Neuroimaging.
The cognitive and behavioral characteristics of children with low working memory.

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Alloway, Tracy Packiam; Gathercole, Susan Elizabeth; Kirkwood, Hannah; Elliott, Julian

2009-01-01

This study explored the cognitive and behavioral profiles of children with working memory impairments. In an initial screening of 3,189 five- to eleven-year-olds, 308 were identified as having very low working memory scores. Cognitive skills (IQ, vocabulary, reading, and math), classroom behavior, and self-esteem were assessed. The majority of the children struggled in the learning measures and verbal ability. They also obtained atypically high ratings of cognitive problems/inattentive symptoms and were judged to have short attention spans, high levels of distractibility, problems in monitoring the quality of their work, and difficulties in generating new solutions to problems. These data provide rich new information on the cognitive and behavioral profiles that characterize children with low working memory.
Spatial memory impairment is associated with hippocampal insulin signals in ovariectomized rats.

Science.gov (United States)

Wang, Fang; Song, Yan-Feng; Yin, Jie; Liu, Zi-Hua; Mo, Xiao-Dan; Wang, De-Gui; Gao, Li-Ping; Jing, Yu-Hong

2014-01-01

Estrogen influences memory formation and insulin sensitivity. Meanwhile, glucose utilization directly affects learning and memory, which are modulated by insulin signals. Therefore, this study investigated whether or not the effect of estrogen on memory is associated with the regulatory effect of this hormone on glucose metabolism. The relative expression of estrogen receptor β (ERβ) and glucose transporter type 4 (GLUT4) in the hippocampus of rats were evaluated by western blot. Insulin level was assessed by ELISA and quantitative RT-PCR, and spatial memory was tested by the Morris water maze. Glucose utilization in the hippocampus was measured by 2-NBDG uptake analysis. Results showed that ovariectomy impaired the spatial memory of rats. These impairments are similar as the female rats treated with the ERβ antagonist tamoxifen (TAM). Estrogen blockade by ovariectomy or TAM treatment obviously decreased glucose utilization. This phenomenon was accompanied by decreased insulin level and GLUT4 expression in the hippocampus. The female rats were neutralized with hippocampal insulin with insulin antibody, which also impaired memory and local glucose consumption. These results indicated that estrogen blockade impaired the spatial memory of the female rats. The mechanisms by which estrogen blockade impaired memory partially contributed to the decline in hippocampal insulin signals, which diminished glucose consumption.
How Human Memory and Working Memory Work in Second Language Acquisition

OpenAIRE

小那覇, 洋子; Onaha, Hiroko

2014-01-01

We often draw an analogy between human memory and computers. Information around us is taken into our memory storage first, and then we use the information in storage whatever we need it in our daily life. Linguistic information is also in storage and we process our thoughts based on the memory that is stored. Memory storage consists of multiple memory systems; one of which is called working memory that includes short-term memory. Working memory is the central system that underpins the process...
Damage of GABAergic neurons in the medial septum impairs spatial working memory and extinction of active avoidance: effects on proactive interference.

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Pang, Kevin C H; Jiao, Xilu; Sinha, Swamini; Beck, Kevin D; Servatius, Richard J

2011-08-01

The medial septum and diagonal band (MSDB) are important in spatial learning and memory. On the basis of the excitotoxic damage of GABAergic MSDB neurons, we have recently suggested a role for these neurons in controlling proactive interference. Our study sought to test this hypothesis in different behavioral procedures using a new GABAergic immunotoxin. GABA-transporter-saporin (GAT1-SAP) was administered into the MSDB of male Sprague-Dawley rats. Following surgery, rats were trained in a reference memory water maze procedure for 5 days, followed by a working memory (delayed match to position) water maze procedure. Other rats were trained in a lever-press avoidance procedure after intraseptal GAT1-SAP or sham surgery. Intraseptal GAT1-SAP extensively damaged GABAergic neurons while sparing most cholinergic MSDB neurons. Rats treated with GAT1-SAP were not impaired in acquiring a spatial reference memory, learning the location of the escape platform as rapidly as sham rats. In contrast, GAT1-SAP rats were slower than sham rats to learn the platform location in a delayed match to position procedure, in which the platform location was changed every day. Moreover, GAT1-SAP rats returned to previous platform locations more often than sham rats. In the active avoidance procedure, intraseptal GAT1-SAP impaired extinction but not acquisition of the avoidance response. Using a different neurotoxin and behavioral procedures than previous studies, the results of this study paint a similar picture that GABAergic MSDB neurons are important for controlling proactive interference. Copyright © 2010 Wiley-Liss, Inc.
Hippocampal damage and memory impairment in congenital cyanotic heart disease.

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Muñoz-López, Mónica; Hoskote, Aparna; Chadwick, Martin J; Dzieciol, Anna M; Gadian, David G; Chong, Kling; Banks, Tina; de Haan, Michelle; Baldeweg, Torsten; Mishkin, Mortimer; Vargha-Khadem, Faraneh

2017-04-01

Neonatal hypoxia can lead to hippocampal atrophy, which can lead, in turn, to memory impairment. To test the generalizability of this causal sequence, we examined a cohort of 41 children aged 8-16, who, having received the arterial switch operation to correct for transposition of the great arteries, had sustained significant neonatal cyanosis but were otherwise neurodevelopmentally normal. As predicted, the cohort had significant bilateral reduction of hippocampal volumes relative to the volumes of 64 normal controls. They also had significant, yet selective, impairment of episodic memory as measured by standard tests of memory, despite relatively normal levels of intelligence, academic attainment, and verbal fluency. Across the cohort, degree of memory impairment was correlated with degree of hippocampal atrophy suggesting that even as early as neonatal life no other structure can fully compensate for hippocampal injury and its special role in serving episodic long term memory. © 2017 Wiley Periodicals, Inc. © 2017 The Authors. Hippocampus Published by Wiley Periodicals, Inc.
Impaired cue identification and intention retrieval underlie prospective memory deficits in patients with first-episode schizophrenia.

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Liu, Dengtang; Ji, Chengfeng; Zhuo, Kaiming; Song, Zhenhua; Wang, Yingchan; Mei, Li; Zhu, Dianming; Xiang, Qiong; Chen, Tianyi; Yang, Zhilei; Zhu, Guang; Wang, Ya; Cheung, Eric Fc; Xiang, Yu-Tao; Fan, Xiaoduo; Chan, Raymond Ck; Xu, Yifeng; Jiang, Kaida

2017-03-01

Schizophrenia is associated with impairment in prospective memory, the ability to remember to carry out an intended action in the future. It has been established that cue identification (detection of the cue event signaling that an intended action should be performed) and intention retrieval (retrieval of an intention from long-term memory following the recognition of a prospective cue) are two important processes underlying prospective memory. The purpose of this study was to examine prospective memory deficit and underlying cognitive processes in patients with first-episode schizophrenia. This study examined cue identification and intention retrieval components of event-based prospective memory using a dual-task paradigm in 30 patients with first-episode schizophrenia and 30 healthy controls. All participants were also administered a set of tests assessing working memory and retrospective memory. Both cue identification and intention retrieval were impaired in patients with first-episode schizophrenia compared with healthy controls ( ps cue identification (Cohen's d = 0.98) and a medium effect size for intention retrieval (Cohen's d = 0.62). After controlling for working memory and retrospective memory, the difference in cue identification between patients and healthy controls remained significant. However, the difference in intention retrieval between the two groups was no longer significant. In addition, there was a significant inverse relationship between cue identification and negative symptoms ( r = -0.446, p = 0.013) in the patient group. These findings suggest that both cue identification and intention retrieval in event-based prospective memory are impaired in patients with first-episode schizophrenia. Cue identification and intention retrieval could be potentially used as biomarkers for early detection and treatment prognosis of schizophrenia. In addition, addressing cue identification deficit through cognitive enhancement training may
Prefrontal cortical GABA modulation of spatial reference and working memory.

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Auger, Meagan L; Floresco, Stan B

2014-10-31

Dysfunction in prefrontal cortex (PFC) GABA transmission has been proposed to contribute to cognitive dysfunction in schizophrenia, yet how this system regulates different cognitive and mnemonic functions remains unclear. We assessed the effects of pharmacological reduction of GABAA signaling in the medial PFC of rats on spatial reference/working memory using different versions of the radial-arm maze task. We used a massed-trials procedure to probe how PFC GABA regulates susceptibility to proactive interference. Male rats were well-trained to retrieve food from the same 4 arms of an 8-arm maze, receiving 5 trials/day (1-2 min intervals). Infusions of the GABAA receptor antagonist bicuculline (12.5-50 ng) markedly increased working and reference memory errors and response latencies. Similar treatments also impaired short-term memory on an 8-baited arm task. These effects did not appear to be due to increased susceptibility to proactive interference. In contrast, PFC inactivation via infusion of GABA agonists baclofen/muscimol did not affect reference/working memory. In comparison to the pronounced effects on the 8-arm maze tasks, PFC GABAA antagonism only causes a slight and transient decrease in accuracy on a 2-arm spatial discrimination. These findings demonstrate that prefrontal GABA hypofunction severely disrupts spatial reference and short-term memory and that disinhibition of the PFC can, in some instances, perturb memory processes not normally dependent on the frontal lobes. Moreover, these impairments closely resemble those observed in schizophrenic patients, suggesting that perturbation in PFC GABA signaling may contribute to these types of cognitive deficits associated with the disorder. © The Author 2014. Published by Oxford University Press on behalf of CINP.
Sleep disturbance induces neuroinflammation and impairment of learning and memory.

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Zhu, Biao; Dong, Yuanlin; Xu, Zhipeng; Gompf, Heinrich S; Ward, Sarah A P; Xue, Zhanggang; Miao, Changhong; Zhang, Yiying; Chamberlin, Nancy L; Xie, Zhongcong

2012-12-01

Hospitalized patients can develop cognitive function decline, the mechanisms of which remain largely to be determined. Sleep disturbance often occurs in hospitalized patients, and neuroinflammation can induce learning and memory impairment. We therefore set out to determine whether sleep disturbance can induce neuroinflammation and impairment of learning and memory in rodents. Five to 6-month-old wild-type C57BL/6J male mice were used in the studies. The mice were placed in rocking cages for 24 h, and two rolling balls were present in each cage. The mice were tested for learning and memory function using the Fear Conditioning Test one and 7 days post-sleep disturbance. Neuroinflammation in the mouse brain tissues was also determined. Of the Fear Conditioning studies at one day and 7 days after sleep disturbance, twenty-four hour sleep disturbance decreased freezing time in the context test, which assesses hippocampus-dependent learning and memory; but not the tone test, which assesses hippocampus-independent learning and memory. Sleep disturbance increased pro-inflammatory cytokine IL-6 levels and induced microglia activation in the mouse hippocampus, but not the cortex. These results suggest that sleep disturbance induces neuroinflammation in the mouse hippocampus, and impairs hippocampus-dependent learning and memory in mice. Pending further studies, these findings suggest that sleep disturbance-induced neuroinflammation and impairment of learning and memory may contribute to the development of cognitive function decline in hospitalized patients. Copyright © 2012 Elsevier Inc. All rights reserved.

Short-term memory in Down syndrome: applying the working memory model.

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Jarrold, C; Baddeley, A D

2001-10-01

This paper is divided into three sections. The first reviews the evidence for a verbal short-term memory deficit in Down syndrome. Existing research suggests that short-term memory for verbal information tends to be impaired in Down syndrome, in contrast to short-term memory for visual and spatial material. In addition, problems of hearing or speech do not appear to be a major cause of difficulties on tests of verbal short-term memory. This suggests that Down syndrome is associated with a specific memory problem, which we link to a potential deficit in the functioning of the 'phonological loop' of Baddeley's (1986) model of working memory. The second section considers the implications of a phonological loop problem. Because a reasonable amount is known about the normal functioning of the phonological loop, and of its role in language acquisition in typical development, we can make firm predictions as to the likely nature of the short-term memory problem in Down syndrome, and its consequences for language learning. However, we note that the existing evidence from studies with individuals with Down syndrome does not fit well with these predictions. This leads to the third section of the paper, in which we consider key questions to be addressed in future research. We suggest that there are two questions to be answered, which follow directly from the contradictory results outlined in the previous section. These are 'What is the precise nature of the verbal short-term memory deficit in Down syndrome', and 'What are the consequences of this deficit for learning'. We discuss ways in which these questions might be addressed in future work.
Cognitive impairments in former patients with work-related stress complaints - one year later.

Science.gov (United States)

Eskildsen, Anita; Andersen, Lars Peter; Pedersen, Anders Degn; Andersen, Johan Hviid

2016-11-01

Patients on sick leave due to work-related stress often present with cognitive impairments. The aim of this prospective cohort study was to examine the long-term consequences of prolonged work-related stress in terms of cognitive functioning one year after initial professional care seeking. We tested a group of patients with work-related stress with a comprehensive neuropsychological test battery at two occasions, one year apart. At both time points, we compared the performance of patients with healthy controls matched pairwise on sex, age and length of education. This paper presents the results from the one-year follow-up. When adjusting for practice effects, patients improved on measures of prospective memory and processing speed. However, patients continued to perform worse than controls on all tests, though only half of the comparisons reached statistical significance. The effect sizes of the differences between the two groups at one-year follow-up were small to medium. In conclusion, former patients with prolonged work-related stress improved, but they continued to perform worse than controls after one year. In the acute phase, the largest impairments were related to executive function and mental speed but at follow-up memory impairments also became apparent.
Dorso- and ventro-lateral prefrontal volume and spatial working memory in schizotypal personality disorder.

Science.gov (United States)

Goldstein, Kim E; Hazlett, Erin A; Savage, Kimberley R; Berlin, Heather A; Hamilton, Holly K; Zelmanova, Yuliya; Look, Amy E; Koenigsberg, Harold W; Mitsis, Effie M; Tang, Cheuk Y; McNamara, Margaret; Siever, Larry J; Cohen, Barry H; New, Antonia S

2011-04-15

Schizotypal personality disorder (SPD) individuals and borderline personality disorder (BPD) individuals have been reported to show neuropsychological impairments and abnormalities in brain structure. However, relationships between neuropsychological function and brain structure in these groups are not well understood. This study compared visual-spatial working memory (SWM) and its associations with dorsolateral prefrontal cortex (DLPFC) and ventrolateral prefrontal cortex (VLPFC) gray matter volume in 18 unmedicated SPD patients with no BPD traits, 18 unmedicated BPD patients with no SPD traits, and 16 healthy controls (HC). Results showed impaired SWM in SPD but not BPD, compared with HC. Moreover, among the HC group, but not SPD patients, better SWM performance was associated with larger VLPFC (BA44/45) gray matter volume (Fisher's Z p-values <0.05). Findings suggest spatial working memory impairments may be a core neuropsychological deficit specific to SPD patients and highlight the role of VLPFC subcomponents in normal and dysfunctional memory performance. Published by Elsevier B.V.
Neural correlates of true and false memory in mild cognitive impairment.

Science.gov (United States)

Sweeney-Reed, Catherine M; Riddell, Patricia M; Ellis, Judi A; Freeman, Jayne E; Nasuto, Slawomir J

2012-01-01

The goal of this research was to investigate the changes in neural processing in mild cognitive impairment. We measured phase synchrony, amplitudes, and event-related potentials in veridical and false memory to determine whether these differed in participants with mild cognitive impairment compared with typical, age-matched controls. Empirical mode decomposition phase locking analysis was used to assess synchrony, which is the first time this analysis technique has been applied in a complex cognitive task such as memory processing. The technique allowed assessment of changes in frontal and parietal cortex connectivity over time during a memory task, without a priori selection of frequency ranges, which has been shown previously to influence synchrony detection. Phase synchrony differed significantly in its timing and degree between participant groups in the theta and alpha frequency ranges. Timing differences suggested greater dependence on gist memory in the presence of mild cognitive impairment. The group with mild cognitive impairment had significantly more frontal theta phase locking than the controls in the absence of a significant behavioural difference in the task, providing new evidence for compensatory processing in the former group. Both groups showed greater frontal phase locking during false than true memory, suggesting increased searching when no actual memory trace was found. Significant inter-group differences in frontal alpha phase locking provided support for a role for lower and upper alpha oscillations in memory processing. Finally, fronto-parietal interaction was significantly reduced in the group with mild cognitive impairment, supporting the notion that mild cognitive impairment could represent an early stage in Alzheimer's disease, which has been described as a 'disconnection syndrome'.
Neural Correlates of True and False Memory in Mild Cognitive Impairment

Science.gov (United States)

Sweeney-Reed, Catherine M.; Riddell, Patricia M.; Ellis, Judi A.; Freeman, Jayne E.; Nasuto, Slawomir J.

2012-01-01

The goal of this research was to investigate the changes in neural processing in mild cognitive impairment. We measured phase synchrony, amplitudes, and event-related potentials in veridical and false memory to determine whether these differed in participants with mild cognitive impairment compared with typical, age-matched controls. Empirical mode decomposition phase locking analysis was used to assess synchrony, which is the first time this analysis technique has been applied in a complex cognitive task such as memory processing. The technique allowed assessment of changes in frontal and parietal cortex connectivity over time during a memory task, without a priori selection of frequency ranges, which has been shown previously to influence synchrony detection. Phase synchrony differed significantly in its timing and degree between participant groups in the theta and alpha frequency ranges. Timing differences suggested greater dependence on gist memory in the presence of mild cognitive impairment. The group with mild cognitive impairment had significantly more frontal theta phase locking than the controls in the absence of a significant behavioural difference in the task, providing new evidence for compensatory processing in the former group. Both groups showed greater frontal phase locking during false than true memory, suggesting increased searching when no actual memory trace was found. Significant inter-group differences in frontal alpha phase locking provided support for a role for lower and upper alpha oscillations in memory processing. Finally, fronto-parietal interaction was significantly reduced in the group with mild cognitive impairment, supporting the notion that mild cognitive impairment could represent an early stage in Alzheimer’s disease, which has been described as a ‘disconnection syndrome’. PMID:23118992
Semantic memory impairment in the earliest phases of Alzheimer's disease

DEFF Research Database (Denmark)

Vogel, Asmus; Gade, Anders; Stokholm, Jette

2005-01-01

The presence and the nature of semantic memory dysfunction in Alzheimer's disease (AD) have been widely debated. This study aimed to determine the frequency of impaired semantic test performances in mild AD and to study whether incipient semantic impairments could be identified in predementia AD....... Five short neuropsychological tests sensitive to semantic memory and easily applicable in routine practice were administered to 102 patients with mild AD (Mini-Mental State Examination score above 19), 22 predementia AD patients and 58 healthy subjects. 'Category fluency' and 'naming of famous faces......' were the most frequently impaired tests in both patient groups. The study demonstrated that impairments on semantically related tests are common in mild AD and may exist prior to the clinical diagnosis. The results imply that assessment of semantic memory is relevant in the evaluation of patients...
Binding across space and time in visual working memory.

Science.gov (United States)

Karlsen, Paul Johan; Allen, Richard J; Baddeley, Alan D; Hitch, Graham J

2010-04-01

Recent studies of visual short-term memory have suggested that the binding of features such as color and shape into remembered objects is relatively automatic. A series of seven experiments broadened this investigation by comparing the immediate retention of colored shapes with performance when color and shape were separated either spatially or temporally, with participants required actively to form the bound object. Attentional load was manipulated with a demanding concurrent task, and retention in working memory was then tested using a single recognition probe. Both spatial and temporal separation of features tended to impair performance, as did the concurrent task. There was, however, no evidence for greater attentional disruption of performance as a result of either spatial or temporal separation of features. Implications for the process of binding in visual working memory are discussed, and an interpretation is offered in terms of the episodic buffer component of working memory, which is assumed to be a passive store capable of holding bound objects, but not of performing the binding.
Weight and see: Loading working memory improves incidental identification of irrelevant faces

Directory of Open Access Journals (Sweden)

David eCarmel

2012-08-01

Full Text Available Are task-irrelevant stimuli processed to a level enabling individual identification? This question is central both for perceptual processing models and for applied settings (e.g., eyewitness testimony. Lavie’s load theory proposes that working memory actively maintains attentional prioritization of relevant over irrelevant information. Loading working memory thus impairs attentional prioritization, leading to increased processing of task-irrelevant stimuli. Previous research has shown that increased working memory load leads to greater interference effects from response competing distractors. Here we test the novel prediction that increased processing of irrelevant stimuli under high working memory load should lead to a greater likelihood of incidental identification of entirely irrelevant stimuli. To test this, we asked participants to perform a word-categorization task while ignoring task-irrelevant images. The categorization task was performed during the retention interval of a working memory task with either low or high load (defined by memory set size. Following the final experimental trial, a surprise question assessed incidental identification of the irrelevant image. Loading working memory was found to improve identification of task-irrelevant faces, but not of building stimuli (shown in a separate experiment to be less distracting. These findings suggest that working memory plays a critical role in determining whether distracting stimuli will be subsequently identified.
Why does brain damage impair memory? A connectionist model of object recognition memory in perirhinal cortex.

Science.gov (United States)

Cowell, Rosemary A; Bussey, Timothy J; Saksida, Lisa M

2006-11-22

Object recognition is the canonical test of declarative memory, the type of memory putatively impaired after damage to the temporal lobes. Studies of object recognition memory have helped elucidate the anatomical structures involved in declarative memory, indicating a critical role for perirhinal cortex. We offer a mechanistic account of the effects of perirhinal cortex damage on object recognition memory, based on the assumption that perirhinal cortex stores representations of the conjunctions of visual features possessed by complex objects. Such representations are proposed to play an important role in memory when it is difficult to solve a task using representations of only individual visual features of stimuli, thought to be stored in regions of the ventral visual stream caudal to perirhinal cortex. The account is instantiated in a connectionist model, in which development of object representations with visual experience provides a mechanism for judgment of previous occurrence. We present simulations addressing the following empirical findings: (1) that impairments after damage to perirhinal cortex (modeled by removing the "perirhinal cortex" layer of the network) are exacerbated by lengthening the delay between presentation of to-be-remembered items and test, (2) that such impairments are also exacerbated by lengthening the list of to-be-remembered items, and (3) that impairments are revealed only when stimuli are trial unique rather than repeatedly presented. This study shows that it may be possible to account for object recognition impairments after damage to perirhinal cortex within a hierarchical, representational framework, in which complex conjunctive representations in perirhinal cortex play a critical role.
Better target detection in the presence of collinear flankers under high working memory load

Directory of Open Access Journals (Sweden)

Jan W. De Fockert

2014-10-01

Full Text Available There are multiple ways in which working memory can influence selective attention. Aside from the content-specific effects of working memory on selective attention, whereby attention is more likely to be directed towards information that matches the contents of working memory, the mere level of load on working memory has also been shown to have an effect on selective attention. Specifically, high load on working memory is associated with increased processing of irrelevant information. In most demonstrations of the effect to-date, this has led to impaired target performance, leaving open the possibility that the effect partly reflects an increase in general task difficulty under high load. Here we show that working memory load can result in a performance gain when processing of distracting information aids target performance. The facilitation in the detection of a low-contrast Gabor stimulus in the presence of collinear flanking Gabors was greater when load on a concurrent working memory task was high, compared to low. This finding suggests that working memory can interact with selective attention at an early stage in visual processing.
Selective impairments in spatial memory after ischaemic stroke

NARCIS (Netherlands)

Kessels, RPC; de Haan, EHF; Kappelle, LJ; Postma, A

2002-01-01

There is evidence that object-location memory consists of three separate processes, that is, positional memory, binding of objects to locations, and a possible integration mechanism. A group of 26 patients with lesions following ischaemic stroke was studied to find evidence for selective impairments
High working memory load impairs the effect of cognitive reappraisal on emotional response: Evidence from an event-related potential study.

Science.gov (United States)

Gan, Shuzhen; Yang, Jianfeng; Chen, Xuhai; Zhang, Xiuping; Yang, Yufang

2017-02-03

This study investigates how the working memory (WM) load influenced the efficacy of cognitive reappraisal, a frequently used strategy for emotion regulation. In a dual-task paradigm, the participants were required to perform a high-load or a low-load memory task and simultaneously reappraise aversive pictures with a negative or a neutral meaning. In the low-load condition, we found that the amplitude of emotion-enhanced late positive potential (LPP) was significantly decreased by neutral reappraisal compared to negative reappraisal. In the high-load condition, this regulatory effect of reappraisal disappeared. These results suggest that successful reappraisal relies on cognitive resources and WM processes. If the necessary resources involved in reappraisal are over-depleted by a concurrent memory task, the reappraisal effect will be impaired. Moreover, we found that emotion-enhanced LPP was significant in both of the high-load and low-load tasks, which suggests that emotional electrocortical response may not be susceptible to the available resources. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
Functional Dissociation of Confident and Not-Confident Errors in the Spatial Delayed Response Task Demonstrates Impairments in Working Memory Encoding and Maintenance in Schizophrenia

Directory of Open Access Journals (Sweden)

Jutta S. Mayer

2018-05-01

Full Text Available Even though extensively investigated, the nature of working memory (WM deficits in patients with schizophrenia (PSZ is not yet fully understood. In particular, the contribution of different WM sub-processes to the severe WM deficit observed in PSZ is a matter of debate. So far, most research has focused on impaired WM maintenance. By analyzing different types of errors in a spatial delayed response task (DRT, we have recently demonstrated that incorrect yet confident responses (which we labeled as false memory errors rather than incorrect/not-confident responses reflect failures of WM encoding, which was also impaired in PSZ. In the present study, we provide further evidence for a functional dissociation between confident and not-confident errors by manipulating the demands on WM maintenance, i.e., the length over which information has to be maintained in WM. Furthermore, we investigate whether these functionally distinguishable WM processes are impaired in PSZ. Twenty-four PSZ and 24 demographically matched healthy controls (HC performed a spatial DRT in which the length of the delay period was varied between 1, 2, 4, and 6 s. In each trial, participants also rated their level of response confidence. Across both groups, longer delays led to increased rates of incorrect/not-confident responses, while incorrect/confident responses were not affected by delay length. This functional dissociation provides additional support for our proposal that false memory errors (i.e., confident errors reflect problems at the level of WM encoding, while not-confident errors reflect failures of WM maintenance. Schizophrenic patients showed increased numbers of both confident and not-confident errors, suggesting that both sub-processes of WM—encoding and maintenance—are impaired in schizophrenia. Combined with the delay length-dependent functional dissociation, we propose that these impairments in schizophrenic patients are functionally distinguishable.
Working memory and attention deficits in adolescent offspring of schizophrenia or bipolar patients: comparing vulnerability markers.

Science.gov (United States)

Diwadkar, Vaibhav A; Goradia, Dhruman; Hosanagar, Avinash; Mermon, Diana; Montrose, Debra M; Birmaher, Boris; Axelson, David; Rajarathinem, R; Haddad, Luay; Amirsadri, Ali; Zajac-Benitez, Caroline; Rajan, Usha; Keshavan, Matcheri S

2011-07-01

Working memory deficits abound in schizophrenia and attention deficits have been documented in schizophrenia and bipolar disorder. Adolescent offspring of patients may inherit vulnerabilities in brain circuits that subserve these cognitive domains. Here we assess impairments in offspring of schizophrenia (SCZ-Offspring) or bipolar (BP-Offspring) patients compared to controls (HC) with no family history of mood or psychotic disorders to the second degree. Three groups (n=100 subjects; range: 10-20 yrs) of HC, SCZ-Offspring and BP-Offspring gave informed consent. Working memory was assessed using a delayed spatial memory paradigm with two levels of delay (2s & 12s); sustained attention processing was assessed using the Continuous Performance Task-Identical Pairs version. SCZ-Offspring (but not BP-Offspring) showed impairments in working memory (relative to HC) at the longer memory delay indicating a unique deficit. Both groups showed reduced sensitivity during attention but only BP-Offspring significantly differed from controls. These results suggest unique (working memory/dorsal frontal cortex) and potentially overlapping (attention/fronto-striatal cortex) vulnerability pathways in adolescent offspring of patients with schizophrenia and bipolar disorder. Working memory and attention assessments in these offspring may assist in the clinical characterization of the adolescents vulnerable to SCZ or BP. Copyright © 2011 Elsevier Inc. All rights reserved.
Both a Nicotinic Single Nucleotide Polymorphism (SNP) and a Noradrenergic SNP Modulate Working Memory Performance when Attention Is Manipulated

Science.gov (United States)

Greenwood, Pamela M.; Sundararajan, Ramya; Lin, Ming-Kuan; Kumar, Reshma; Fryxell, Karl J.; Parasuraman, Raja

2009-01-01

We investigated the relation between the two systems of visuospatial attention and working memory by examining the effect of normal variation in cholinergic and noradrenergic genes on working memory performance under attentional manipulation. We previously reported that working memory for location was impaired following large location precues,…
Selective attention supports working memory maintenance by modulating perceptual processing of distractors.

Science.gov (United States)

Sreenivasan, Kartik K; Jha, Amishi P

2007-01-01

Selective attention has been shown to bias sensory processing in favor of relevant stimuli and against irrelevant or distracting stimuli in perceptual tasks. Increasing evidence suggests that selective attention plays an important role during working memory maintenance, possibly by biasing sensory processing in favor of to-be-remembered items. In the current study, we investigated whether selective attention may also support working memory by biasing processing against irrelevant and potentially distracting information. Event-related potentials (ERPs) were recorded while subjects (n = 22) performed a delayed-recognition task for faces and shoes. The delay period was filled with face or shoe distractors. Behavioral performance was impaired when distractors were congruent with the working memory domain (e.g., face distractor during working memory for faces) relative to when distractors were incongruent with the working memory domain (e.g., face distractor during shoe working memory). If attentional biasing against distractor processing is indeed functionally relevant in supporting working memory maintenance, perceptual processing of distractors is predicted to be attenuated when distractors are more behaviorally intrusive relative to when they are nonintrusive. As such, we predicted that perceptual processing of distracting faces, as measured by the face-sensitive N170 ERP component, would be reduced in the context of congruent (face) working memory relative to incongruent (shoe) working memory. The N170 elicited by distracting faces demonstrated reduced amplitude during congruent versus incongruent working memory. These results suggest that perceptual processing of distracting faces may be attenuated due to attentional biasing against sensory processing of distractors that are most behaviorally intrusive during working memory maintenance.
Working memory training may increase working memory capacity but not fluid intelligence.

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Harrison, Tyler L; Shipstead, Zach; Hicks, Kenny L; Hambrick, David Z; Redick, Thomas S; Engle, Randall W

2013-12-01

Working memory is a critical element of complex cognition, particularly under conditions of distraction and interference. Measures of working memory capacity correlate positively with many measures of real-world cognition, including fluid intelligence. There have been numerous attempts to use training procedures to increase working memory capacity and thereby performance on the real-world tasks that rely on working memory capacity. In the study reported here, we demonstrated that training on complex working memory span tasks leads to improvement on similar tasks with different materials but that such training does not generalize to measures of fluid intelligence.
Effects of noise and working memory capacity on memory processing of speech for hearing-aid users

OpenAIRE

Ng, Hoi Ning, Elaine; Rudner, Mary; Lunner, Thomas; Syskind Perdersen, Michael; Rönnberg, Jerker

2013-01-01

Objectives: It has been shown that noise reduction algorithms can reduce the negative effects of noise on memory processing in persons with normal hearing. The objective of the present study was to investigate whether a similar effect can be obtained for persons with hearing impairment and whether such an effect is dependent on individual differences in working memory capacity. Design: A sentence-final word identification and recall (SWIR) test was conducted in two noise backgrounds with and ...
The impact of auditory working memory training on the fronto-parietal working memory network

OpenAIRE

Schneiders, Julia A.; Opitz, Bertram; Tang, Huijun; Deng, Yuan; Xie, Chaoxiang; Li, Hong; Mecklinger, Axel

2012-01-01

Working memory training has been widely used to investigate working memory processes. We have shown previously that visual working memory benefits only from intra-modal visual but not from across-modal auditory working memory training. In the present functional magnetic resonance imaging study we examined whether auditory working memory processes can also be trained specifically and which training-induced activation changes accompany theses effects. It was investigated whether working memory ...
Glucocorticoids interact with the hippocampal endocannabinoid system in impairing retrieval of contextual fear memory

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Atsak, Piray; Hauer, Daniela; Campolongo, Patrizia; Schelling, Gustav; McGaugh, James L.; Roozendaal, Benno

2012-01-01

There is extensive evidence that glucocorticoid hormones impair the retrieval of memory of emotionally arousing experiences. Although it is known that glucocorticoid effects on memory retrieval impairment depend on rapid interactions with arousal-induced noradrenergic activity, the exact mechanism underlying this presumably nongenomically mediated glucocorticoid action remains to be elucidated. Here, we show that the hippocampal endocannabinoid system, a rapidly activated retrograde messenger system, is involved in mediating glucocorticoid effects on retrieval of contextual fear memory. Systemic administration of corticosterone (0.3–3 mg/kg) to male Sprague–Dawley rats 1 h before retention testing impaired the retrieval of contextual fear memory without impairing the retrieval of auditory fear memory or directly affecting the expression of freezing behavior. Importantly, a blockade of hippocampal CB1 receptors with AM251 prevented the impairing effect of corticosterone on retrieval of contextual fear memory, whereas the same impairing dose of corticosterone increased hippocampal levels of the endocannabinoid 2-arachidonoylglycerol. We also found that antagonism of hippocampal β-adrenoceptor activity with local infusions of propranolol blocked the memory retrieval impairment induced by the CB receptor agonist WIN55,212–2. Thus, these findings strongly suggest that the endocannabinoid system plays an intermediary role in regulating rapid glucocorticoid effects on noradrenergic activity in impairing memory retrieval of emotionally arousing experiences. PMID:22331883

Unilateral hippocampal inactivation or lesion selectively impairs remote contextual fear memory.

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Zhou, Heng; Zhou, Qixin; Xu, Lin

2016-10-01

Contextual fear memory depends on the hippocampus, but the role of unilateral hippocampus in this type of memory remains unclear. Herein, pharmacological inactivation or excitotoxic lesions were used to study the role of unilateral hippocampus in the stages of contextual fear memory. The pharmacological experiments revealed that compared with the control groups, unilateral hippocampal blockade did not impair 1-day recent memory following learning, whereas bilateral hippocampal blockade significantly impaired this memory. The lesion experiments showed that compared with the control groups, the formed contextual fear memory was retained for 7 days and that 30-day remote memory was markedly reduced in unilateral hippocampal lesion groups. These results indicate that an intact bilateral hippocampus is required for the formation of remote memory and that unilateral hippocampus is sufficient for recent contextual fear memory.
Prefrontal activity and impaired memory encoding strategies in schizophrenia.

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Guimond, Synthia; Hawco, Colin; Lepage, Martin

2017-08-01

Schizophrenia patients have significant memory difficulties that have far-reaching implications in their daily life. These impairments are partly attributed to an inability to self-initiate effective memory encoding strategies, but its core neurobiological correlates remain unknown. The current study addresses this critical gap in our knowledge of episodic memory impairments in schizophrenia. Schizophrenia patients (n = 35) and healthy controls (n = 23) underwent a Semantic Encoding Memory Task (SEMT) during an fMRI scan. Brain activity was examined for conditions where participants were a) prompted to use semantic encoding strategies, or b) not prompted but required to self-initiate such strategies. When prompted to use semantic encoding strategies, schizophrenia patients exhibited similar recognition performance and brain activity as healthy controls. However, when required to self-initiate these strategies, patients had significant reduced recognition performance and brain activity in the left dorsolateral prefrontal cortex, as well as in the left temporal gyrus, left superior parietal lobule, and cerebellum. When patients were divided based on performance on the SEMT, the subgroup with more severe deficits in self-initiation also showed greater reduction in left dorsolateral prefrontal activity. These results suggest that impaired self-initiation of elaborative encoding strategies is a driving feature of memory deficits in schizophrenia. We also identified the neural correlates of impaired self-initiation of semantic encoding strategies, in which a failure to activate the left dorsolateral prefrontal cortex plays a key role. These findings provide important new targets in the development of novel treatments aiming to improve memory and ultimately patients' outcome. Copyright © 2017. Published by Elsevier Ltd.
Caspase-2 cleavage of tau reversibly impairs memory.

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Zhao, Xiaohui; Kotilinek, Linda A; Smith, Benjamin; Hlynialuk, Chris; Zahs, Kathleen; Ramsden, Martin; Cleary, James; Ashe, Karen H

2016-11-01

In Alzheimer's disease (AD) and other tauopathies, the tau protein forms fibrils, which are believed to be neurotoxic. However, fibrillar tau has been dissociated from neuron death and network dysfunction, suggesting the involvement of nonfibrillar species. Here we describe a novel pathological process in which caspase-2 cleavage of tau at Asp314 impairs cognitive and synaptic function in animal and cellular models of tauopathies by promoting the missorting of tau to dendritic spines. The truncation product, Δtau314, resists fibrillation and is present at higher levels in brains from cognitively impaired mice and humans with AD. The expression of tau mutants that resisted caspase-2 cleavage prevented tau from infiltrating spines, dislocating glutamate receptors and impairing synaptic function in cultured neurons, and it prevented memory deficits and neurodegeneration in mice. Decreasing the levels of caspase-2 restored long-term memory in mice that had existing deficits. Our results suggest an overall treatment strategy for re-establishing synaptic function and restoring memory in patients with AD by preventing tau from accumulating in dendritic spines.
Exaggerated blood pressure variability is associated with memory impairment in very elderly patients.

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Fujiwara, Takeshi; Hoshide, Satoshi; Kanegae, Hiroshi; Eguchi, Kazuo; Kario, Kazuomi

2018-04-01

We investigated the association between working memory (WM) impairment and blood pressure variability (BPV) in very elderly patients. Japanese outpatients ≥80 years who engaged in normal activities of daily living were the study cohort. WM function was evaluated by a simple visual WM test consisting of 3 figures. We considered the number of figures recalled by the patient his/her test score. We defined the patients with a score of 0 or 1 as those with WM impairment and those with scores of 2 or 3 as those without. To investigate the relative risk of WM impairment, we evaluated each patient's 24 hour ambulatory systolic blood pressure (SBP) and its weighted standard deviation (SD SBP ), office SBP, and the visit-to-visit SD SBP during the 1 year period from the patient's enrollment. A total of 66 patients (mean 84 ± 3.6 years) showed WM impairment, and 431 patients (mean 83 ± 3.1 years) showed no WM impairment. There were no significant differences in 24 hour ambulatory SBP or office SBP between these two groups. However, the WM impairment patients showed significantly higher weighted SD SBP and visit-to-visit SD SBP values compared to the no-impairment group even after adjusting for age. Among these ≥80-year-old patients, those with the highest quartile of both weighted SD SBP (≥21.4 mm Hg) and visit-to-visit SD SBP (≥14.5 mm Hg) showed the highest relative risk (odds ratio 3.52, 95% confidence interval 1.42-8.72) for WM impairment. Exaggerated blood pressure variability parameters were significantly associated with working memory impairment in very elderly individuals. ©2018 Wiley Periodicals, Inc.
Item memory, source memory, and the medial temporal lobe: Concordant findings from fMRI and memory-impaired patients

OpenAIRE

Gold, Jeffrey J.; Smith, Christine N.; Bayley, Peter J.; Shrager, Yael; Brewer, James B.; Stark, Craig E. L.; Hopkins, Ramona O.; Squire, Larry R.

2006-01-01

We studied item and source memory with fMRI in healthy volunteers and carried out a parallel study in memory-impaired patients. In experiment 1, volunteers studied a list of words in the scanner and later took an item memory test and a source memory test. Brain activity in the hippocampal region, perirhinal cortex, and parahippocampal cortex was associated with words that would later be remembered (item memory). The activity in these regions that predicted subsequent success at item memory pr...
Long-term effect of early-life stress from earthquake exposure on working memory in adulthood.

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Li, Na; Wang, Yumei; Zhao, Xiaochuan; Gao, Yuanyuan; Song, Mei; Yu, Lulu; Wang, Lan; Li, Ning; Chen, Qianqian; Li, Yunpeng; Cai, Jiajia; Wang, Xueyi

2015-01-01

The present study aimed to investigate the long-term effect of 1976 Tangshan earthquake exposure in early life on performance of working memory in adulthood. A total of 907 study subjects born and raised in Tangshan were enrolled in this study. They were divided into three groups according to the dates of birth: infant exposure (3-12 months, n=274), prenatal exposure (n=269), and no exposure (born at least 1 year after the earthquake, n=364). The prenatal group was further divided into first, second, and third trimester subgroups based on the timing of exposure during pregnancy. Hopkins Verbal Learning Test-Revised and Brief Visuospatial Memory Test-Revised (BVMT-R) were used to measure the performance of working memory. Unconditional logistic regression analysis was used to analyze the influential factors for impaired working memory. The Hopkins Verbal Learning Test-Revised scores did not show significant difference across the three groups. Compared with no exposure group, the BVMT-R scores were slightly lower in the prenatal exposure group and markedly decreased in the infant exposure group. When the BVMT-R scores were analyzed in three subgroups, the results showed that the subjects whose mothers were exposed to earthquake in the second and third trimesters of pregnancy had significantly lower BVMT-R scores compared with those in the first trimester. Education level and early-life earthquake exposure were identified as independent risk factors for reduced performance of visuospatial memory indicated by lower BVMT-R scores. Infant exposure to earthquake-related stress impairs visuospatial memory in adulthood. Fetuses in the middle and late stages of development are more vulnerable to stress-induced damage that consequently results in impaired visuospatial memory. Education and early-life trauma can also influence the performance of working memory in adulthood.
Memory complaints in subjective cognitive impairment, amnestic mild cognitive impairment and mild Alzheimer's disease.

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Ryu, Seon Young; Lee, Sang Bong; Kim, Tae Woo; Lee, Taek Jun

2016-12-01

Memory complaints are a frequent phenomenon in elderly individuals and can lead to opportunistic help-seeking behavior. The aim of this study was to compare different aspects of memory complaints (i.e., prospective versus retrospective complaints) in individuals with subjective cognitive impairment (SCI), amnestic mild cognitive impairment (aMCI), and mild Alzheimer's disease (AD). The study included a total of 115 participants (mean age: 68.82 ± 8.83 years) with SCI (n = 34), aMCI (n = 46), and mild AD (n = 35). Memory complaints were assessed using the Prospective and Retrospective Memory Questionnaire (PRMQ), which consists of 16 items that describe everyday memory failure of both prospective memory (PM) and retrospective memory (RM). For aMCI and AD subjects, informants also completed an informant-rating of the PRMQ. All participants completed detailed neuropsychological tests. Results show that PM complaints were equivalent among the three groups. However, RM complaints differed. Specifically, RM complaints in aMCI were higher than SCI, but similar to AD. Informant-reported memory complaints were higher for AD than aMCI. Our study suggests that RM complaints of memory complaints may be helpful in discriminating between SCI and aMCI, but both PM and RM complaints are of limited value in differentiating aMCI from AD.
The impact of bilingualism on working memory in pediatric epilepsy

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Veenstra, Amy L.; Riley, Jeffrey D.; Barrett, Lauren E.; Muhonen, Michael G.; Zupanc, Mary; Romain, Jonathan E.; Lin, Jack J.; Mucci, Grace

2016-01-01

Impairments in executive skills broadly span across multiple childhood epilepsy syndromes and can adversely affect quality of life. Bilingualism has been previously shown to correlate with enhanced executive functioning in healthy individuals. This study seeks to determine whether the bilingual advantage in executive functioning exists in the context of pediatric epilepsy. We retrospectively analyzed neuropsychological data in 52 children with epilepsy and compared executive function scores in monolingual versus bilingual children with epilepsy, while controlling for socioeconomic status and ethnicity. Bilingual children performed significantly better on the Working Memory scale than did monolingual children. There were no significant differences on the remaining executive function variables. The bilingual advantage appears to persist for working memory in children with epilepsy. These findings suggest that bilingualism is potentially a protective variable in the face of epilepsy-related working memory dysfunction. PMID:26720703
Conceptual similarity effects on working memory in sentence contexts: testing a theory of anaphora.

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Cowles, H Wind; Garnham, Alan; Simner, Julia

2010-06-01

The degree of semantic similarity between an anaphoric noun phrase (e.g., the bird) and its antecedent (e.g., a robin) is known to affect the anaphor resolution process, but the mechanisms that underlie this effect are not known. One proposal (Almor, 1999) is that semantic similarity triggers interference effects in working memory and makes two crucial assumptions: First, semantic similarity impairs working memory just as phonological similarity does (e.g., Baddeley, 1992), and, second, this impairment interferes with processes of sentence comprehension. We tested these assumptions in two experiments that compared recall accuracy between phonologically similar, semantically similar, and control words in sentence contexts. Our results do not provide support for Almor's claims: Phonological overlap decreased recall accuracy in sentence contexts, but semantic similarity did not. These results shed doubt on the idea that semantic interference in working memory is an underlying mechanism in anaphor resolution.
Interactive effects of morphine and dopaminergic compounds on spatial working memory in rhesus monkeys

Institute of Scientific and Technical Information of China (English)

Jian-Hong Wang; Joshua Dominie Rizak; Yan-Mei Chen; Liang Li; Xin-Tian Hu; Yuan-Ye Ma

2013-01-01

Opiates and dopamine (DA) play key roles in learning and memory in humans and animals.Although interactions between these neurotransmitters have been found,their functional roles remain to be fully elucidated,and their dysfunction may contribute to human diseases and addiction.Here we investigated the interactions of morphine and dopaminergic neurotransmitter systems with respect to learning and memory in rhesus monkeys by using the Wisconsin General Test Apparatus (WGTA) delayed-response task.Morphine and DA agonists (SKF-38393,apomorphine and bromocriptine) or DA antagonists (SKF-83566,haloperidol and sulpiride) were co-administered to the monkeys 30 min prior to the task.We found that dose-patterned co-administration of morphine with D1 or D2 antagonists or agonists reversed the impaired spatial working memory induced by morphine or the compounds alone.For example,morphine at 0.01 mg/kg impaired spatial working memory,while morphine (0.01 mg/kg) and apomorphine (0.01 or 0.06 mg/kg) co-treatment ameliorated this effect.Our findings suggest that the interactions between morphine and dopaminergic compounds influence spatial working memory in rhesus monkeys.A better understanding of these interactive relationships may provide insights into human addiction.
Gummed-up memory: Chewing gum impairs short-term recall

OpenAIRE

Kozlov, Michail D; Hughes, Robert W; Jones, Dylan M

2012-01-01

Several studies have suggested that short-term memory is generally improved by chewing gum. However, we report the first studies to show that chewing gum impairs short-term memory for both item order and item identity. Experiment 1 showed that chewing gum reduces serial recall of letter lists. Experiment 2 indicated that chewing does not simply disrupt vocal-articulatory planning required for order retention: Chewing equally impairs a matched task that required retention of list item identity...
Pantomimes are special gestures which rely on working memory.

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Bartolo, A; Cubelli, R; Della Sala, S; Drei, S

2003-12-01

The case of a patient is reported who presented consistently with overt deficits in producing pantomimes in the absence of any other deficits in producing meaningful gestures. This pattern of spared and impaired abilities is difficult to reconcile with the current layout of cognitive models for praxis. This patient also showed clear impairment in a dual-task paradigm, a test taxing the co-ordination aspect of working memory, though performed normally in a series of other neuropsychological measures assessing language, visuo-spatial functions, reasoning function, and executive function. A specific working memory impairment associated with a deficit of pantomiming in the absence of any other disorders in the production of meaningful gestures suggested a way to modify the model to account for the data. Pantomimes are a particular category of gestures, meaningful, yet novel. We posit that by their very nature they call for the intervention of a mechanism to integrate and synthesise perceptual inputs together with information made available from the action semantics (knowledge about objects and functions) and the output lexicon (stored procedural programmes). This processing stage conceived as a temporary workspace where gesture information is actively manipulated, would generate new motor programmes to carry out pantomimes. The model of gesture production is refined to include this workspace.
The Auditory-Visual Speech Benefit on Working Memory in Older Adults with Hearing Impairment.

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Frtusova, Jana B; Phillips, Natalie A

2016-01-01

This study examined the effect of auditory-visual (AV) speech stimuli on working memory in older adults with poorer-hearing (PH) in comparison to age- and education-matched older adults with better hearing (BH). Participants completed a working memory n-back task (0- to 2-back) in which sequences of digits were presented in visual-only (i.e., speech-reading), auditory-only (A-only), and AV conditions. Auditory event-related potentials (ERP) were collected to assess the relationship between perceptual and working memory processing. The behavioral results showed that both groups were faster in the AV condition in comparison to the unisensory conditions. The ERP data showed perceptual facilitation in the AV condition, in the form of reduced amplitudes and latencies of the auditory N1 and/or P1 components, in the PH group. Furthermore, a working memory ERP component, the P3, peaked earlier for both groups in the AV condition compared to the A-only condition. In general, the PH group showed a more robust AV benefit; however, the BH group showed a dose-response relationship between perceptual facilitation and working memory improvement, especially for facilitation of processing speed. Two measures, reaction time and P3 amplitude, suggested that the presence of visual speech cues may have helped the PH group to counteract the demanding auditory processing, to the level that no group differences were evident during the AV modality despite lower performance during the A-only condition. Overall, this study provides support for the theory of an integrated perceptual-cognitive system. The practical significance of these findings is also discussed.
Effect of an NCAM mimetic peptide FGL on impairment in spatial learning and memory after neonatal phencyclidine treatment in rats

DEFF Research Database (Denmark)

Secher, Thomas; Berezin, Vladimir; Bock, Elisabeth

2008-01-01

treatment regimen where FGL was administered throughout development. Rats were tested as adults for spatial reference memory, reversal learning, and working memory in the Morris water maze. The PCP-treated rats demonstrated a robust impairment in working memory and reversal learning. However, the long-term......The FGL peptide is a neural cell adhesion molecule-derived fibroblast growth factor receptor agonist. FGL has both neurotrophic and memory enhancing properties. Neonatal phencyclidine (PCP) treatment on postnatal days 7, 9, and 11 has been shown to result in long-lasting behavioral abnormalities......, including cognitive impairment relevant to schizophrenia. The present study investigated the effect of FGL on spatial learning and memory deficits induced by neonatal PCP treatment. Rat pups were treated with 30mg/kg PCP on postnatal days 7, 9, and 11. Additionally, the rats were subjected to a chronic FGL...
Reconstructions of Information in Visual Spatial Working Memory Degrade with Memory Load

OpenAIRE

Sprague, Thomas C.; Ester, Edward F.; Serences, John T.

2014-01-01

Working memory (WM) enables the maintenance and manipulation of information relevant to behavioral goals. Variability in WM ability is strongly correlated with IQ [1] and WM function is impaired in many neurological and psychiatric disorders [2, 3], suggesting that this system is a core component of higher cognition. WM storage is thought to be mediated by patterns of activity in neural populations selective for specific properties (e.g., color, orientation, location, motion direction) of mem...
Enhanced Long-Term and Impaired Short-Term Spatial Memory in GluA1 AMPA Receptor Subunit Knockout Mice: Evidence for a Dual-Process Memory Model

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Sanderson, David J.; Good, Mark A.; Skelton, Kathryn; Sprengel, Rolf; Seeburg, Peter H.; Rawlins, J. Nicholas P.; Bannerman, David M.

2009-01-01

The GluA1 AMPA receptor subunit is a key mediator of hippocampal synaptic plasticity and is especially important for a rapidly-induced, short-lasting form of potentiation. GluA1 gene deletion impairs hippocampus-dependent, spatial working memory, but spares hippocampus-dependent spatial reference memory. These findings may reflect the necessity of…
Auditory Association Cortex Lesions Impair Auditory Short-Term Memory in Monkeys

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Colombo, Michael; D'Amato, Michael R.; Rodman, Hillary R.; Gross, Charles G.

1990-01-01

Monkeys that were trained to perform auditory and visual short-term memory tasks (delayed matching-to-sample) received lesions of the auditory association cortex in the superior temporal gyrus. Although visual memory was completely unaffected by the lesions, auditory memory was severely impaired. Despite this impairment, all monkeys could discriminate sounds closer in frequency than those used in the auditory memory task. This result suggests that the superior temporal cortex plays a role in auditory processing and retention similar to the role the inferior temporal cortex plays in visual processing and retention.
Work-related stress is associated with impaired neuropsychological test performance: a clinical cross-sectional study.

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Eskildsen, Anita; Andersen, Lars Peter; Pedersen, Anders Degn; Vandborg, Sanne Kjær; Andersen, Johan Hviid

2015-01-01

Patients on sick leave due to work-related stress often complain about impaired concentration and memory. However, it is undetermined how widespread these impairments are, and which cognitive domains are most long-term stress sensitive. Previous studies show inconsistent results and are difficult to synthesize. The primary aim of this study was to examine whether patients with work-related stress complaints have cognitive impairments compared to a matched control group without stress. Our secondary aim was to examine whether the level of self-reported perceived stress is associated with neuropsychological test performance. We used a broad neuropsychological test battery to assess 59 outpatients with work-related stress complaints (without major depression) and 59 healthy controls. We matched the patients and controls pairwise by sex, age and educational level. Compared to controls, patients generally showed mildly reduced performance across all the measured domains of the neuropsychological test battery. However, only three comparisons reached statistical significance (p working memory. There were no statistical significant associations between self-reported perceived stress level and neuropsychological test performance. In conclusion, we recommend that cognitive functions should be considered when evaluating patients with work-related stress complaints, especially when given advice regarding return to work. Since this study had a cross-sectional design, it is still uncertain whether the impairments are permanent. Further study is required to establish causal links between work-related stress and cognitive deficits.
The Role of Aging in Intra-Item and Item-Context Binding Processes in Visual Working Memory

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Peterson, Dwight J.; Naveh-Benjamin, Moshe

2016-01-01

Aging is accompanied by declines in both working memory and long-term episodic memory processes. Specifically, important age-related memory deficits are characterized by performance impairments exhibited by older relative to younger adults when binding distinct components into a single integrated representation, despite relatively intact memory…
A Comparison of Alzheimer\\'s Patients and Healthy Elders in Relationship between Components of Working Memory and Sentence Comprehension

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Raziyeh A'lemi

2010-10-01

Full Text Available Objective: The aim of this study was to investigate the relation between working memory and sentence comprehension. Patients with Dementia of the Alzheimer´s type (DAT and matched older volunteers were tested on a battery of working memory tests, as well as on test of sentence comprehension. Materials & Methods: This is a cross-sectional study. Statistical population included all patients with Alzheimer disease who were registered in the center of Alzheimer (Imam Ali in Tehran.10 patients randomly were selected among them, according to inclusive and exclusive criteria. For data collection, epidemiological information questionnaire, Mental Mini State Examination (MMSE, working memory tests and sentence comprehension were applied. Data were analyzed by Independent T-test and correlation analyses. Results: Patients had impaired central executive processes in working memory (P=0.006, but showed normal effects of phonological and articulatory variables on span (P=0.480. On the sentence comprehension tasks (simple and complicated sentences, DAT patients showed significant differences with their peers (simple s. P=0.001, complicated s. P=0.004. Impairment in the central executive processes of working memory in DAT patients was correlated with the complicated sentences on the sentence comprehension tasks. Conclusion: The results suggest that patients with DAT have working memory impairments that are related to their ability to map the meaning on sentences on to depictions of events in the world.

Chronic stress during adolescence impairs and improves learning and memory in adulthood

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Lauren Evelyn Chaby

2015-12-01

Full Text Available Exposure to acute stress can cause a myriad of cognitive impairments, but whether negative experiences continue to hinder individual as they age is not well understood. We determined how chronic unpredictable stress during adolescence affects multiple learning and memory processes in adulthood. Using male Sprague Dawley rats, we measured learning (both associative and reversal and memory (both reference and working starting 110 days after completion of the adolescent-stress treatment. We found that adolescent stress affected adult cognitive abilities in a context-dependent way. Compared to rats reared without stress, adolescent-stressed rats exhibited enhanced reversal learning, an indicator of behavioral flexibility, but showed no change in associative learning and reference memory abilities. Working memory, which in humans is thought to underpin reasoning, mathematical skills, and reading comprehension, may be enhanced by exposure to adolescent stress. However, when adolescent-stressed animals were tested after a novel disturbance, they exhibited a 5-fold decrease in working memory performance while unstressed rats continued to exhibit a linear learning curve. These results emphasize the capacity for stress during adolescence to transform the cognitive abilities of adult animals, even after stress exposure has ceased and animals have resided in safe environments for the majority of their lifespans.
Sulforaphane Prevents Neuronal Apoptosis and Memory Impairment in Diabetic Rats

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Gengyin Wang

2016-08-01

Full Text Available Background/Aims: To explore the effects of sulforaphane (SFN on neuronal apoptosis in hippocampus and memory impairment in diabetic rats. Methods: Thirty male rats were randomly divided into normal control, diabetic model and SFN treatment groups (N = 10 in each group. Streptozotocin (STZ was applied to establish diabetic model. Water Morris maze task was applied to test learning and memory. Tunel assaying was used to detect apoptosis in hippocampus. The expressions of Caspase-3 and myeloid cell leukemia 1(MCL-1 were detected by western blotting. Neurotrophic factor levels and AKT/GSK3β pathway were also detected. Results: Compared with normal control, learning and memory were apparently impaired, with up-regulation of Caspase-3 and down-regulation of MCL-1 in diabetic rats. Apoptotic neurons were also found in CA1 region after diabetic modeling. By contrast, SFN treatment prevented the memory impairment, decreased the apoptosis of hippocampal neurons. SFN also attenuated the abnormal expression of Caspase-3 and MCL-1 in diabetic model. Mechanically, SFN treatment reversed diabetic modeling-induced decrease of p-Akt, p-GSK3β, NGF and BDNF expressions. Conclusion: SFN could prevent the memory impairment and apoptosis of hippocampal neurons in diabetic rat. The possible mechanism was related to the regulation of neurotropic factors and Akt/GSK3β pathway.
Sleep-dependent memory consolidation in healthy aging and mild cognitive impairment.

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Pace-Schott, Edward F; Spencer, Rebecca M C

2015-01-01

Sleep quality and architecture as well as sleep's homeostatic and circadian controls change with healthy aging. Changes include reductions in slow-wave sleep's (SWS) percent and spectral power in the sleep electroencephalogram (EEG), number and amplitude of sleep spindles, rapid eye movement (REM) density and the amplitude of circadian rhythms, as well as a phase advance (moved earlier in time) of the brain's circadian clock. With mild cognitive impairment (MCI) there are further reductions of sleep quality, SWS, spindles, and percent REM, all of which further diminish, along with a profound disruption of circadian rhythmicity, with the conversion to Alzheimer's disease (AD). Sleep disorders may represent risk factors for dementias (e.g., REM Behavior Disorder presages Parkinson's disease) and sleep disorders are themselves extremely prevalent in neurodegenerative diseases. Working memory , formation of new episodic memories, and processing speed all decline with healthy aging whereas semantic, recognition, and emotional declarative memory are spared. In MCI, episodic and working memory further decline along with declines in semantic memory. In young adults, sleep-dependent memory consolidation (SDC) is widely observed for both declarative and procedural memory tasks. However, with healthy aging, although SDC for declarative memory is preserved, certain procedural tasks, such as motor-sequence learning, do not show SDC. In younger adults, fragmentation of sleep can reduce SDC, and a normative increase in sleep fragmentation may account for reduced SDC with healthy aging. Whereas sleep disorders such as insomnia, obstructive sleep apnea, and narcolepsy can impair SDC in the absence of neurodegenerative changes, the incidence of sleep disorders increases both with normal aging and, further, with neurodegenerative disease. Specific features of sleep architecture, such as sleep spindles and SWS are strongly linked to SDC. Diminution of these features with healthy aging
Unimodal and crossmodal working memory representations of visual and kinesthetic movement trajectories.

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Seemüller, Anna; Fiehler, Katja; Rösler, Frank

2011-01-01

The present study investigated whether visual and kinesthetic stimuli are stored as multisensory or modality-specific representations in unimodal and crossmodal working memory tasks. To this end, angle-shaped movement trajectories were presented to 16 subjects in delayed matching-to-sample tasks either visually or kinesthetically during encoding and recognition. During the retention interval, a secondary visual or kinesthetic interference task was inserted either immediately or with a delay after encoding. The modality of the interference task interacted significantly with the encoding modality. After visual encoding, memory was more impaired by a visual than by a kinesthetic secondary task, while after kinesthetic encoding the pattern was reversed. The time when the secondary task had to be performed interacted with the encoding modality as well. For visual encoding, memory was more impaired, when the secondary task had to be performed at the beginning of the retention interval. In contrast, memory after kinesthetic encoding was more affected, when the secondary task was introduced later in the retention interval. The findings suggest that working memory traces are maintained in a modality-specific format characterized by distinct consolidation processes that take longer after kinesthetic than after visual encoding. Copyright Â© 2010 Elsevier B.V. All rights reserved.
Detailed sensory memory, sloppy working memory

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Ilja G Sligte

2010-10-01

Full Text Available Visual short-term memory (VSTM enables us to actively maintain information in mind for a brief period of time after stimulus disappearance. According to recent studies, VSTM consists of three stages - iconic memory, fragile VSTM, and visual working memory - with increasingly stricter capacity limits and progressively longer lifetimes. Still, the resolution (or amount of visual detail of each VSTM stage has remained unexplored and we test this in the present study. We presented people with a change detection task that measures the capacity of all three forms of VSTM, and we added an identification display after each change trial that required people to identify the pre-change object. Accurate change detection plus pre-change identification requires subjects to have a high-resolution representation of the pre-change object, whereas change detection or identification only can be based on the hunch that something has changed, without exactly knowing what was presented before. We observed that people maintained 6.1 objects in iconic memory, 4.6 objects in fragile VSTM and 2.1 objects in visual working memory. Moreover, when people detected the change, they could also identify the pre-change object on 88 percent of the iconic memory trials, on 71 percent of the fragile VSTM trials and merely on 53 percent of the visual working memory trials. This suggests that people maintain many high-resolution representations in iconic memory and fragile VSTM, but only one high-resolution object representation in visual working memory.
Detailed sensory memory, sloppy working memory.

Science.gov (United States)

Sligte, Ilja G; Vandenbroucke, Annelinde R E; Scholte, H Steven; Lamme, Victor A F

2010-01-01

Visual short-term memory (VSTM) enables us to actively maintain information in mind for a brief period of time after stimulus disappearance. According to recent studies, VSTM consists of three stages - iconic memory, fragile VSTM, and visual working memory - with increasingly stricter capacity limits and progressively longer lifetimes. Still, the resolution (or amount of visual detail) of each VSTM stage has remained unexplored and we test this in the present study. We presented people with a change detection task that measures the capacity of all three forms of VSTM, and we added an identification display after each change trial that required people to identify the "pre-change" object. Accurate change detection plus pre-change identification requires subjects to have a high-resolution representation of the "pre-change" object, whereas change detection or identification only can be based on the hunch that something has changed, without exactly knowing what was presented before. We observed that people maintained 6.1 objects in iconic memory, 4.6 objects in fragile VSTM, and 2.1 objects in visual working memory. Moreover, when people detected the change, they could also identify the pre-change object on 88% of the iconic memory trials, on 71% of the fragile VSTM trials and merely on 53% of the visual working memory trials. This suggests that people maintain many high-resolution representations in iconic memory and fragile VSTM, but only one high-resolution object representation in visual working memory.
Is working memory still working?

Science.gov (United States)

Baddeley, A D

2001-11-01

The current state of A. D. Baddeley and G. J. Hitch's (1974) multicomponent working memory model is reviewed. The phonological and visuospatial subsystems have been extensively investigated, leading both to challenges over interpretation of individual phenomena and to more detailed attempts to model the processes underlying the subsystems. Analysis of the controlling central executive has proved more challenging, leading to a proposed clarification in which the executive is assumed to be a limited capacity attentional system, aided by a newly postulated fourth system, the episodic buffer. Current interest focuses most strongly on the link between working memory and long-term memory and on the processes allowing the integration of information from the component subsystems. The model has proved valuable in accounting for data from a wide range of participant groups under a rich array of task conditions. Working memory does still appear to be working.
Effects of mild cognitive impairment on emotional scene memory.

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Waring, J D; Dimsdale-Zucker, H R; Flannery, S; Budson, A E; Kensinger, E A

2017-02-01

Young and older adults experience benefits in attention and memory for emotional compared to neutral information, but this memory benefit is greatly diminished in Alzheimer's disease (AD). Little is known about whether this impairment arises early or late in the time course between healthy aging and AD. This study compared memory for positive, negative, and neutral items with neutral backgrounds between patients with mild cognitive impairment (MCI) and healthy older adults. We also used a divided attention condition in older adults as a possible model for the deficits observed in MCI patients. Results showed a similar pattern of selective memory for emotional items while forgetting their backgrounds in older adults and MCI patients, but MCI patients had poorer memory overall. Dividing attention during encoding disproportionately reduced memory for backgrounds (versus items) relative to a full attention condition. Participants performing in the lower half on the divided attention task qualitatively and quantitatively mirrored the results in MCI patients. Exploratory analyses comparing lower- and higher-performing MCI patients showed that only higher-performing MCI patients had the characteristic scene memory pattern observed in healthy older adults. Together, these results suggest that the effects of emotion on memory are relatively well preserved for patients with MCI, although emotional memory patterns may start to be altered once memory deficits become more pronounced. Copyright © 2017 Elsevier Ltd. All rights reserved.
The chemotherapeutic agent paclitaxel selectively impairs reversal learning while sparing prior learning, new learning and episodic memory.

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Panoz-Brown, Danielle; Carey, Lawrence M; Smith, Alexandra E; Gentry, Meredith; Sluka, Christina M; Corbin, Hannah E; Wu, Jie-En; Hohmann, Andrea G; Crystal, Jonathon D

2017-10-01

Chemotherapy is widely used to treat patients with systemic cancer. The efficacy of cancer therapies is frequently undermined by adverse side effects that have a negative impact on the quality of life of cancer survivors. Cancer patients who receive chemotherapy often experience chemotherapy-induced cognitive impairment across a variety of domains including memory, learning, and attention. In the current study, the impact of paclitaxel, a taxane derived chemotherapeutic agent, on episodic memory, prior learning, new learning, and reversal learning were evaluated in rats. Neurogenesis was quantified post-treatment in the dentate gyrus of the same rats using immunostaining for 5-Bromo-2'-deoxyuridine (BrdU) and Ki67. Paclitaxel treatment selectively impaired reversal learning while sparing episodic memory, prior learning, and new learning. Furthermore, paclitaxel-treated rats showed decreases in markers of hippocampal cell proliferation, as measured by markers of cell proliferation assessed using immunostaining for Ki67 and BrdU. This work highlights the importance of using multiple measures of learning and memory to identify the pattern of impaired and spared aspects of chemotherapy-induced cognitive impairment. Copyright © 2017 Elsevier Inc. All rights reserved.
The impact of bilingualism on working memory in pediatric epilepsy.

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Veenstra, Amy L; Riley, Jeffrey D; Barrett, Lauren E; Muhonen, Michael G; Zupanc, Mary; Romain, Jonathan E; Lin, Jack J; Mucci, Grace

2016-02-01

Impairments in executive skills broadly span across multiple childhood epilepsy syndromes and can adversely affect quality of life. Bilingualism has been previously shown to correlate with enhanced executive functioning in healthy individuals. This study sought to determine whether the bilingual advantage in executive functioning exists in the context of pediatric epilepsy. We retrospectively analyzed neuropsychological data in 52 children with epilepsy and compared executive function scores in monolingual versus bilingual children with epilepsy while controlling for socioeconomic status and ethnicity. Bilingual children performed significantly better on the Working Memory Index than did monolingual children. There were no significant differences on the remaining executive function variables. The bilingual advantage appears to persist for working memory in children with epilepsy. These findings suggest that bilingualism is potentially a protective variable in the face of epilepsy-related working memory dysfunction. Copyright © 2015 Elsevier Inc. All rights reserved.
Negative attitude towards medication is associated with working memory impairment in schizophrenia patients.

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Goodman, Craig; Knoll, Gabriella; Isakov, Victoria; Silver, Henry

2005-03-01

A lack of insight into illness and negative attitudes towards medication are common among individuals with schizophrenia and impact clinical outcomes. This study aimed to examine the relationships between attitudes towards medication and cognitive function in schizophrenia patients. Thirty-five male forensic inpatients who were suffering from chronic schizophrenia participated in the study. A drug attitude inventory was used to evaluate the attitudes of the patients towards medication. Neuropsychological function was assessed with a comprehensive battery of tests. Patients with positive attitudes towards medication performed significantly better than those with negative attitudes on tests of verbal working memory (digit span forwards and backwards), inhibition and set shifting (Penn Inhibition test), delayed object memory and overall mental status (Mini Mental State Examination). There were no differences in age, education, hospitalizations or clinical symptoms between the groups. Our findings support an association between negative attitudes towards medication and poor cognitive performance, particularly of working memory.
Sleep, Torpor and Memory Impairment

Science.gov (United States)

Palchykova, S.; Tobler, I.

It is now well known that daily torpor induces a sleep deficit. Djungarian hamsters emerging from this hypometabolic state spend most of the time in sleep. This sleep is characterized by high initial values of EEG slow-wave activity (SWA) that monotonically decline during recovery sleep. These features resemble the changes seen in numerous species during recovery after prolonged wakefulness or sleep deprivation (SD). When hamsters are totally or partially sleep deprived immediately after emerging from torpor, an additional increase in SWA can be induced. It has been therefore postulated, that these slow- waves are homeostatically regulated, as predicted by the two-process model of sleep regulation, and that during daily torpor a sleep deficit is accumulated as it is during prolonged waking. The predominance of SWA in the frontal EEG observed both after SD and daily torpor provides further evidence for the similarity of these conditions. It has been shown in several animal and human studies that sleep can enhance memory consolidation, and that SD leads to memory impairment. Preliminary data obtained in the Djungarian hamster showed that both SD and daily torpor result in object recognition deficits. Thus, animals subjected to SD immediately after learning, or if they underwent an episode of daily torpor between learning and retention, displayed impaired recognition memory for complex object scenes. The investigation of daily torpor can reveal mechanisms that could have important implications for hypometabolic state induction in other mammalian species, including humans.
The Auditory-Visual Speech Benefit on Working Memory in Older Adults with Hearing Impairment

OpenAIRE

Frtusova, Jana B.; Phillips, Natalie A.

2016-01-01

This study examined the effect of auditory-visual (AV) speech stimuli on working memory in older adults with poorer-hearing (PH) in comparison to age- and education-matched older adults with better hearing (BH). Participants completed a working memory n-back task (0- to 2-back) in which sequences of digits were presented in visual-only (i.e., speech-reading), auditory-only (A-only), and AV conditions. Auditory event-related potentials (ERP) were collected to assess the relationship between pe...
Influence of pharmacological manipulations of NMDA and cholinergic receptors on working versus reference memory in a dual component odor span task.

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MacQueen, David A; Dalrymple, Savannah R; Drobes, David J; Diamond, David M

2016-06-01

Developed as a tool to assess working memory capacity in rodents, the odor span task (OST) has significant potential to advance drug discovery in animal models of psychiatric disorders. Prior investigations indicate OST performance is impaired by systemic administration of N-methyl-d-aspartate receptor (NMDA-r) antagonists and is sensitive to cholinergic manipulations. The present study sought to determine whether an impairment in OST performance can be produced by systemic administration of the competitive NMDA-r antagonist 3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP; 3, 10, 17 mg/kg i.p.) in a unique dual-component variant of the OST, and whether this impairment is ameliorated by nicotine (0.75 mg/kg i.p.). Male Sprague-Dawley rats were trained to asymptotic level of performance on a 24-trial two-comparison incrementing nonmatching to sample OST. In addition, rats were administered a two-comparison olfactory reference memory (RM) task, which was integrated into the OST. The RM task provided an assessment of the effects of drug administration on global behavioral measures, long-term memory and motivation. Several measures of working memory (span, longest run, and accuracy) were dose dependently impaired by CPP without adversely affecting RM. Analysis of drug effects across trial blocks demonstrated a significant impairment of performance even at low memory loads, suggesting a CPP-induced deficit of olfactory short-term memory that is not load-dependent. Although nicotine did not ameliorate CPP-induced impairments in span or accuracy, it did block the impairment in longest run produced by the 10 mg/kg dose of CPP. Overall, our results indicate that performance in our 24 odor two-comparison OST is capacity dependent and that CPP impaired OST working, but not reference, memory. © 2016 MacQueen et al.; Published by Cold Spring Harbor Laboratory Press.
Histamine H3 receptor density is negatively correlated with neural activity related to working memory in humans.

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Ito, Takehito; Kimura, Yasuyuki; Seki, Chie; Ichise, Masanori; Yokokawa, Keita; Kawamura, Kazunori; Takahashi, Hidehiko; Higuchi, Makoto; Zhang, Ming-Rong; Suhara, Tetsuya; Yamada, Makiko

2018-06-14

The histamine H 3 receptor is regarded as a drug target for cognitive impairments in psychiatric disorders. H 3 receptors are expressed in neocortical areas, including the prefrontal cortex, the key region of cognitive functions such as working memory. However, the role of prefrontal H 3 receptors in working memory has not yet been clarified. Therefore, using functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) techniques, we aimed to investigate the association between the neural activity of working memory and the density of H 3 receptors in the prefrontal cortex. Ten healthy volunteers underwent both fMRI and PET scans. The N-back task was used to assess the neural activities related to working memory. H 3 receptor density was measured with the selective PET radioligand [ 11 C] TASP457. The neural activity of the right dorsolateral prefrontal cortex during the performance of the N-back task was negatively correlated with the density of H 3 receptors in this region. Higher neural activity of working memory was associated with lower H 3 receptor density in the right dorsolateral prefrontal cortex. This finding elucidates the role of H 3 receptors in working memory and indicates the potential of H 3 receptors as a therapeutic target for the cognitive impairments associated with neuropsychiatric disorders.
Poor Performance on Serial Visual Tasks in Persons with Reading Disabilities: Impaired Working Memory?

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Ram-Tsur, Ronit; Faust, Miriam; Zivotofsky, Ari Z.

2008-01-01

The present study investigates the performance of persons with reading disabilities (PRD) on a variety of sequential visual-comparison tasks that have different working-memory requirements. In addition, mediating relationships between the sequential comparison process and attention and memory skills were looked for. Our findings suggest that PRD…
Crocin Improved Learning and Memory Impairments in Streptozotocin-Induced Diabetic Rats

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Esmaeal Tamaddonfard

2013-01-01

Full Text Available Objective(s: Crocin influences many biological functions including memory and learning. The present study was aimed to investigate the effects of crocin on learning and memory impairments in streptozotocine-induced diabetic rats. Materials and Methods: Diabetes was induced by intraperitoneal (IP injection of streptozotocin (STZ, 45 mg/kg. Transfer latency (TL paradigm in elevated plus-maze (EPM was used as an index of learning and memory. Plasma levels of total antioxidant capacity (TAC and malondialdehyde (MDA, blood levels of glucose, and serum concentrations of insulin were measured. The number of hippocampal neurons was also counted. Results: STZ increased acquisition transfer latency (TL1 and retention transfer latency (TL2, and MDA, decreased transfer latency shortening (TLs and TCA, produced hyperglycemia and hypoinsulinemia, and reduced the number of neurons in the hippocampus. Learning and memory impairments and blood TCA, MDA, glucose, and insulin changes induced by streptozotocin were improved with long-term IP injection of crocin at doses of 15 and 30 mg/kg. Crocin prevented hippocampal neurons number loss in diabetic rats. Conclusion: The results indicate that oxidative stress, hyperglycemia, hypoinsulinemia, and reduction of hippocampal neurons may be involved in learning and memory impairments in STZ-induced diabetic rats. Antioxidant, antihyperglycemic, antihypoinsulinemic, and neuroprotective activities of crocin might be involved in improving learning and memory impairments.
Emergent Bilingualism and Working Memory Development in School Aged Children

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Hansen, Laura Birke; Macizo, Pedro; Duñabeitia, Jon Andoni; Saldaña, David; Carreiras, Manuel; Fuentes, Luis J.; Bajo, M. Teresa

2016-01-01

The present research explores working memory (WM) development in monolingual as well as emergent bilingual children immersed in an L2 at school. Evidence from recent years suggests that bilingualism may boost domain-general executive control, but impair nonexecutive linguistic processing. Both are relevant for verbal WM, but different paradigms…
Impaired hippocampal acetylcholine release parallels spatial memory deficits in Tg2576 mice subjected to basal forebrain cholinergic degeneration

DEFF Research Database (Denmark)

Laursen, Bettina; Mørk, Arne; Plath, Niels

2013-01-01

(BFCD) in 3 months old male Tg2576 mice to co-express cholinergic degeneration with Aβ overexpression as these characteristics constitutes key hallmarks of AD. At 9 months, SAP lesioned Tg2576 mice were cognitively impaired in two spatial paradigms addressing working memory and mid to long-term memory...
Enhanced effects of cortisol administration on episodic and working memory in aging veterans with PTSD.

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Yehuda, Rachel; Harvey, Philip D; Buchsbaum, Monte; Tischler, Lisa; Schmeidler, James

2007-12-01

Though both glucocorticoid alterations and memory impairments have been noted in posttraumatic stress disorder (PTSD), it is not clear if these phenomena are causally linked. As there is emerging evidence that these domains become further altered in PTSD with increasing age, it is of interest to examine these relationships in an older cohort. Aging (mean age, 62.7+/-8.9; range, 52-81) combat veterans with (n=13) and without (n=17) PTSD received an intravenous bolus of 17.5 mg hydrocortisone (cortisol), a naturally occurring glucocorticoid, or placebo in a randomized, double-blind manner, on two mornings approximately 1-2 weeks apart. Neuropsychological testing to evaluate episodic and working memory performance was performed 75 min later. Cortisol enhanced episodic memory performance in both groups of subjects, but enhanced elements of working memory performance only in the PTSD+ group. The preferential effect of cortisol administration on working memory in PTSD may be related to the superimposition of PTSD and age, as cortisol had impairing effects on this task in a previously studied, younger cohort. The findings suggest that there may be opportunities for developing therapeutic strategies using glucocorticoids in the treatment of aging combat veterans.

Glucose attenuates impairments in memory and CREB activation produced by an α4β2 but not an α7 nicotinic receptor antagonist.

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Morris, Ken A; Li, Sisi; Bui, Duat D; Gold, Paul E

2013-04-01

Glucose improves memory for a variety of tasks when administered to rats and mice near the time of training. Prior work indicates glucose may enhance memory by increasing the synthesis and release of the neurotransmitter acetylcholine in the brain. To investigate if specific acetylcholine receptor subtypes may mediate some of the memory-enhancing actions of glucose, we examined the effects of subtype-specific nicotinic acetylcholine receptor antagonists on memory in Fischer-344 rats and also examined the ability of glucose to reverse drug-induced impairments. Pre-training peripheral injections of methyllycaconitine (MLA) or dihydro-beta-erythroidine (DHβE), which are specific α7 and α4β2 nicotinic receptor antagonists, respectively, dose-dependently impaired retention latencies in an inhibitory avoidance task when tested 7-days but not 1 h after training. Immediate post-training glucose injections attenuated the impairments, but were more effective in attenuating the DHβE-induced impairments. Likewise, peripheral or direct intrahippocampal injections of MLA or DHβE dose-dependently impaired spatial working memory scores on a spontaneous alternation task. Concurrent administration of glucose reversed DHβE- but not MLA-induced impairments. CREB phosphorylation downstream of cholinergic signaling was assessed 30 min after spontaneous alternation testing and intrahippocampal drug infusions. Both MLA and DHβE impaired hippocampal CREB phosphorylation; glucose reversed DHβE- but not MLA-induced deficits. The effectiveness of glucose in reversing DHβE- but not MLA-induced impairments in behavioral performance and CREB phosphorylation suggests that activation of α7 receptors may play an important role in memory enhancement by glucose. Copyright © 2012 Elsevier Ltd. All rights reserved.
Robust training attenuates TBI-induced deficits in reference and working memory on the radial 8-arm maze

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Veronica eSebastian

2013-05-01

Full Text Available Globally, it is estimated that nearly 10 million people sustain severe brain injuries leading to hospitalization and/or death every year. Amongst survivors, traumatic brain injury (TBI results in a wide variety of physical, emotional and cognitive deficits. The most common cognitive deficit associated with TBI is memory loss, involving impairments in spatial reference and working memory. However, the majority of research thus far has characterized the deficits associated with TBI on either reference or working memory systems separately, without investigating how they interact within in a single task. Thus we examined the effects of TBI on short-term working and long-term reference memory using the radial 8-arm maze (RAM with a sequence of 4 baited and 4 unbaited arms. Subjects were given 10 daily trials for 6 days followed by a memory retrieval test two weeks after training. Multiple training trials not only provide robust training, but also test the subjects’ ability to frequently update short-term memory while learning the reference rules of the task. Our results show that TBI significantly impaired short-term working memory function on previously acquired spatial information but has little effect on long-term reference memory. Additionally, TBI significantly increased working memory errors during acquisition and reference memory errors during retention testing two weeks later. With a longer recovery period after TBI, the robust RAM training mitigated the reference memory deficit in retention but not the short-term working memory deficit during acquisition. These results identify the resiliency and vulnerabilities of short-term working and long-term reference memory to TBI in the context of robust training. The data highlight the role of cognitive training and other behavioral remediation strategies implicated in attenuating deficits associated with TBI.
Robust training attenuates TBI-induced deficits in reference and working memory on the radial 8-arm maze.

Science.gov (United States)

Sebastian, Veronica; Diallo, Aissatou; Ling, Douglas S F; Serrano, Peter A

2013-01-01

Globally, it is estimated that nearly 10 million people sustain severe brain injuries leading to hospitalization and/or death every year. Amongst survivors, traumatic brain injury (TBI) results in a wide variety of physical, emotional and cognitive deficits. The most common cognitive deficit associated with TBI is memory loss, involving impairments in spatial reference and working memory. However, the majority of research thus far has characterized the deficits associated with TBI on either reference or working memory systems separately, without investigating how they interact within a single task. Thus, we examined the effects of TBI on short-term working and long-term reference memory using the radial 8-arm maze (RAM) with a sequence of four baited and four unbaited arms. Subjects were given 10 daily trials for 6 days followed by a memory retrieval test 2 weeks after training. Multiple training trials not only provide robust training, but also test the subjects' ability to frequently update short-term memory while learning the reference rules of the task. Our results show that TBI significantly impaired short-term working memory function on previously acquired spatial information but has little effect on long-term reference memory. Additionally, TBI significantly increased working memory errors during acquisition and reference memory errors during retention testing 2 weeks later. With a longer recovery period after TBI, the robust RAM training mitigated the reference memory deficit in retention but not the short-term working memory deficit during acquisition. These results identify the resiliency and vulnerabilities of short-term working and long-term reference memory to TBI in the context of robust training. The data highlight the role of cognitive training and other behavioral remediation strategies implicated in attenuating deficits associated with TBI.
Working memory and referential communication – multimodal aspects of interaction between children with sensorineural hearing impairment and normal hearing peers

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Olof eSandgren

2015-03-01

Full Text Available Whereas the language development of children with sensorineural hearing impairment (SNHI has repeatedly been shown to differ from that of peers with normal hearing (NH, few studies have used an experimental approach to investigate the consequences on everyday communicative interaction. This mini review gives an overview of a range of studies on children with SNHI and NH exploring intra- and inter-individual cognitive and linguistic systems during communication.Over the last decade, our research group has studied the conversational strategies of Swedish speaking children and adolescents with SNHI and NH using referential communication, an experimental analogue to problem-solving in the classroom. We have established verbal and nonverbal control and validation mechanisms, related to working memory capacity (WMC and phonological short term memory (PSTM. We present main findings and future directions relevant for the field of cognitive hearing science and for the clinical and school-based management of children and adolescents with SNHI.
Oscillatory lower body negative pressure impairs working memory task-related functional hyperemia in healthy volunteers.

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Merchant, Sana; Medow, Marvin S; Visintainer, Paul; Terilli, Courtney; Stewart, Julian M

2017-04-01

Neurovascular coupling (NVC) describes the link between an increase in task-related neural activity and increased cerebral blood flow denoted "functional hyperemia." We previously showed induced cerebral blood flow oscillations suppressed functional hyperemia; conversely functional hyperemia also suppressed cerebral blood flow oscillations. We used lower body negative pressure (OLBNP) oscillations to force oscillations in middle cerebral artery cerebral blood flow velocity (CBFv). Here, we used N-back testing, an intellectual memory challenge as a neural activation task, to test the hypothesis that OLBNP-induced oscillatory cerebral blood flow can reduce functional hyperemia and NVC produced by a working memory task and can interfere with working memory. We used OLBNP (-30 mmHg) at 0.03, 0.05, and 0.10 Hz and measured spectral power of CBFv at all frequencies. Neither OLBNP nor N-back, alone or combined, affected hemodynamic parameters. 2-Back power and OLBNP individually were compared with 2-back power during OLBNP. 2-Back alone produced a narrow band increase in oscillatory arterial pressure (OAP) and oscillatory cerebral blood flow power centered at 0.0083 Hz. Functional hyperemia in response to 2-back was reduced to near baseline and 2-back memory performance was decreased by 0.03-, 0.05-, and 0.10-Hz OLBNP. OLBNP alone produced increased oscillatory power at frequencies of oscillation not suppressed by added 2-back. However, 2-back preceding OLBNP suppressed OLBNP power. OLBNP-driven oscillatory CBFv blunts NVC and memory performance, while memory task reciprocally interfered with forced CBFv oscillations. This shows that induced cerebral blood flow oscillations suppress functional hyperemia and functional hyperemia suppresses cerebral blood flow oscillations. NEW & NOTEWORTHY We show that induced cerebral blood flow oscillations suppress functional hyperemia produced by a working memory task as well as memory task performance. We conclude that oscillatory
L-carnitine prevents memory impairment induced by chronic REM-sleep deprivation.

Science.gov (United States)

Alzoubi, Karem H; Rababa'h, Abeer M; Owaisi, Amani; Khabour, Omar F

2017-05-01

Sleep deprivation (SD) negatively impacts memory, which was related to oxidative stress induced damage. L-carnitine is a naturally occurring compound, synthesized endogenously in mammalian species and known to possess antioxidant properties. In this study, the effect of L-carnitine on learning and memory impairment induced by rapid eye movement sleep (REM-sleep) deprivation was investigated. REM-sleep deprivation was induced using modified multiple platform model (8h/day, for 6 weeks). Simultaneously, L-carnitine was administered (300mg/kg/day) intraperitoneally for 6 weeks. Thereafter, the radial arm water maze (RAWM) was used to assess spatial learning and memory. Additionally, the hippocampus levels of antioxidant biomarkers/enzymes: reduced glutathione (GSH), oxidized glutathione (GSSG), GSH/GSSG ratio, glutathione peroxidase (GPx), catalase, and superoxide dismutase (SOD) and thiobarbituric acid reactive substance (TBARS) were assessed. The results showed that chronic REM-sleep deprivation impaired both short- and long-term memory (Psleep deprivation induced reduction in the hippocampus ratio of GSH/GSSG, activity of catalase, GPx, and SOD. No change was observed in TBARS among tested groups (P>0.05). In conclusion, chronic REM-sleep deprivation induced memory impairment, and treatment with L-carnitine prevented this impairment through normalizing antioxidant mechanisms in the hippocampus. Copyright © 2017 Elsevier Inc. All rights reserved.
The Benefits of Working Memory Capacity on Attentional Control under Pressure.

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Luo, Xiaoxiao; Zhang, Liwei; Wang, Jin

2017-01-01

The present study aimed to examine the effects of working memory capacity (WMC) and state anxiety (SA) on attentional control. WMC was manipulated by (a) dividing participants into low- and high-WMC groups (Experiment 1), and (b) using working memory training to improve WMC (Experiment 2). SA was manipulated by creating low- and high-SA conditions. Attentional control was evaluated by using antisaccade task. Results demonstrated that (a) higher WMC indicated better attentional control (Experiments 1 and 2); (b) the effects of SA on attentional control were inconsistent because SA impaired attentional control in Experiment 1, but favored attentional control in Experiment 2; and (c) the interaction of SA and WMC was not significant (Experiments 1 and 2). This study directly manipulated WMC by working memory training, which provided more reliable evidence for controlled attention view of WMC and new supportive evidence for working memory training (i.e., far transfer effect on attentional control). And the refinement of the relationship between anxiety and attentional control proposed by Attentional Control Theory was also discussed.
The Benefits of Working Memory Capacity on Attentional Control under Pressure

Directory of Open Access Journals (Sweden)

Xiaoxiao Luo

2017-07-01

Full Text Available The present study aimed to examine the effects of working memory capacity (WMC and state anxiety (SA on attentional control. WMC was manipulated by (a dividing participants into low- and high-WMC groups (Experiment 1, and (b using working memory training to improve WMC (Experiment 2. SA was manipulated by creating low- and high-SA conditions. Attentional control was evaluated by using antisaccade task. Results demonstrated that (a higher WMC indicated better attentional control (Experiments 1 and 2; (b the effects of SA on attentional control were inconsistent because SA impaired attentional control in Experiment 1, but favored attentional control in Experiment 2; and (c the interaction of SA and WMC was not significant (Experiments 1 and 2. This study directly manipulated WMC by working memory training, which provided more reliable evidence for controlled attention view of WMC and new supportive evidence for working memory training (i.e., far transfer effect on attentional control. And the refinement of the relationship between anxiety and attentional control proposed by Attentional Control Theory was also discussed.
Emotion, working memory task demands and individual differences predict behavior, cognitive effort and negative affect.

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Storbeck, Justin; Davidson, Nicole A; Dahl, Chelsea F; Blass, Sara; Yung, Edwin

2015-01-01

We examined whether positive and negative affect motivates verbal and spatial working memory processes, respectively, which have implications for the expenditure of mental effort. We argue that when emotion promotes cognitive tendencies that are goal incompatible with task demands, greater cognitive effort is required to perform well. We sought to investigate whether this increase in cognitive effort impairs behavioural control over a broad domain of self-control tasks. Moreover, we predicted that individuals with higher behavioural inhibition system (BIS) sensitivities would report more negative affect within the goal incompatible conditions because such individuals report higher negative affect during cognitive challenge. Positive or negative affective states were induced followed by completing a verbal or spatial 2-back working memory task. All participants then completed one of three self-control tasks. Overall, we observed that conditions of emotion and working memory incompatibility (positive/spatial and negative/verbal) performed worse on the self-control tasks, and within the incompatible conditions individuals with higher BIS sensitivities reported more negative affect at the end of the study. The combination of findings suggests that emotion and working memory compatibility reduces cognitive effort and impairs behavioural control.
The Test Your Memory for Mild Cognitive Impairment (TYM-MCI).

Science.gov (United States)

Brown, Jeremy M; Lansdall, Claire J; Wiggins, Julie; Dawson, Kate E; Hunter, Kristina; Rowe, James B; Parker, Richard A

2017-12-01

To validate a short cognitive test: the Test Your Memory for Mild Cognitive Impairment (TYM-MCI) in the diagnosis of patients with amnestic mild cognitive impairment or mild Alzheimer's disease (aMCI/AD). Two hundred and two patients with mild memory problems were recruited. All had 'passed' the Mini-Mental State Examination (MMSE). Patients completed the TYM-MCI, the Test Your Memory test (TYM), MMSE and revised Addenbrooke's Cognitive Examination (ACE-R), had a neurological examination, clinical diagnostics and multidisciplinary team review. As a single test, the TYM-MCI performed as well as the ACE-R in the distinction of patients with aMCI/AD from patients with subjective memory impairment with a sensitivity of 0.79 and specificity of 0.91. Used in combination with the ACE-R, it provided additional value and identified almost all cases of aMCI/AD. The TYM-MCI correctly classified most patients who had equivocal ACE-R scores. Integrated discriminant improvement analysis showed that the TYM-MCI added value to the conventional memory assessment. Patients initially diagnosed as unknown or with subjective memory impairment who were later rediagnosed with aMCI/AD scored poorly on their original TYM-MCI. The TYM-MCI is a powerful short cognitive test that examines verbal and visual recall and is a valuable addition to the assessment of patients with aMCI/AD. It is simple and cheap to administer and requires minimal staff time and training. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Evidence for working memory deficits in chronic pain: a systematic review and meta-analysis.

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Berryman, Carolyn; Stanton, Tasha R; Jane Bowering, K; Tabor, Abby; McFarlane, Alexander; Lorimer Moseley, G

2013-08-01

People with chronic pain commonly report impaired cognitive function. However, to date, there has been no systematic evaluation of the body of literature concerning cognitive impairment and pain. Nor have modern meta-analytical methods been used to verify and clarify the extent to which cognition may be impaired. The objective of this study was to systematically evaluate and critically appraise the literature concerning working memory function in people with chronic pain. The study was conducted along Cochrane collaboration and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines. A sensitive search strategy was designed and conducted with the help of an expert librarian using 6 databases. Twenty-four observational studies evaluating behavioural and/or physiological outcomes in a chronic pain group and a control group met the inclusion criteria. All studies had a high risk of bias, owing primarily to lack of assessor blinding to outcome. High heterogeneity within the field was found with the inclusion of 24 papers using 21 different working memory tests encompassing 9 different working memory constructs and 9 different chronic pain populations. Notwithstanding high heterogeneity, pooled results from behavioural outcomes reflected a consistent, significant moderate effect in favour of better performance by healthy controls and, with the exception of one study, pooled results from physiological outcomes reflected no evidence for an effect. Future research would benefit from the use of clearly defined constructs of working memory, as well as standardised methods of testing. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
FMRI of working memory in patients with mild cognitive impairment and probable Alzheimer's disease

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Yetkin, F. Zerrin; Rosenberg, Roger N.; Weiner, Myron F.; Purdy, Phillip D.; Cullum, C. Munro

2006-01-01

The goals of this study were to evaluate brain activation in patients with probable Alzheimer's disease (AD), mild cognitive impairment (MCI), and controls while performing a working memory (WM) task. Eleven AD patients, ten MCI subjects, and nine controls underwent functional magnetic resonance imaging (fMRI) while performing a visual WM task. Statistical parametric maps of brain activation were obtained in each group, and group activation difference maps were generated. Ability to perform the task did not differ among the groups. Activation was observed in the parahippocampal region, superior-middle-inferior frontal gyri, parietal region, anterior-posterior cingulate, fusiform gyrus, and basal ganglia. MCI and AD groups showed more activation than the controls in the right superior frontal gyrus, bilateral middle temporal, middle frontal, anterior cingulate, and fusiform gyri. Activation in the right parahippocampal gyrus, left inferior frontal gyrus, bilateral cingulate and lingual gyri, right lentiform nucleus, right fusiform gyrus, and left supramarginal gyrus in the AD group was less than in the MCI group. The WM task evoked activation in widely distributed regions, consistent with previous fMRI studies. AD and MCI patients showed an increased extent of activation and recruitment of additional areas. (orig.)
Stress Induction and Visual Working Memory Performance: The Effects of Emotional and Non-Emotional Stimuli

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Zahra Khayyer

2017-05-01

Full Text Available Background Some studies have shown working memory impairment following stressful situations. Also, researchers have found that working memory performance depends on many different factors such as emotional load of stimuli and gender. Objectives The present study aimed to determine the effects of stress induction on visual working memory (VWM performance among female and male university students. Methods This quasi-experimental research employed a posttest with only control group design (within-group study. A total of 62 university students (32 males and 30 females were randomly selected and allocated to experimental and control groups (mean age of 23.73. Using cold presser test (CPT, stress was induced and then, an n-back task was implemented to evaluate visual working memory function (such as the number of true items, time reactions, and the number of wrong items through emotional and non-emotional pictures. 100 pictures were selected from the international affective picture system (IASP with different valences. Results Results showed that stress impaired different visual working memory functions (P < 0.002 for true scores, P < 0.001 for reaction time, and P < 0.002 for wrong items. Conclusions In general, stress significantly decreases the VWM performances. On the one hand, females were strongly impressed by stress more than males and on the other hand, the VWM performance was better for emotional stimuli than non-emotional stimuli.
The Diagnostic Utility of Behavioral Checklists in Identifying Children with ADHD and Children with Working Memory Deficits

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Alloway, Tracy Packiam; Gathercole, Susan E.; Holmes, Joni; Place, Maurice; Elliott, Julian G.; Hilton, Kerry

2009-01-01

The present study investigated whether children with ADHD and those with working memory impairments have a common behavioral profile in the classroom. Three teacher checklists were used: the Conners' teacher rating scale (CTRS), the behavior rating inventory of executive function (BRIEF), and the working memory rating scale. The Conners'…
GABA from reactive astrocytes impairs memory in mouse models of Alzheimer's disease.

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Jo, Seonmi; Yarishkin, Oleg; Hwang, Yu Jin; Chun, Ye Eun; Park, Mijeong; Woo, Dong Ho; Bae, Jin Young; Kim, Taekeun; Lee, Jaekwang; Chun, Heejung; Park, Hyun Jung; Lee, Da Yong; Hong, Jinpyo; Kim, Hye Yun; Oh, Soo-Jin; Park, Seung Ju; Lee, Hyo; Yoon, Bo-Eun; Kim, YoungSoo; Jeong, Yong; Shim, Insop; Bae, Yong Chul; Cho, Jeiwon; Kowall, Neil W; Ryu, Hoon; Hwang, Eunmi; Kim, Daesoo; Lee, C Justin

2014-08-01

In Alzheimer's disease (AD), memory impairment is the most prominent feature that afflicts patients and their families. Although reactive astrocytes have been observed around amyloid plaques since the disease was first described, their role in memory impairment has been poorly understood. Here, we show that reactive astrocytes aberrantly and abundantly produce the inhibitory gliotransmitter GABA by monoamine oxidase-B (Maob) and abnormally release GABA through the bestrophin 1 channel. In the dentate gyrus of mouse models of AD, the released GABA reduces spike probability of granule cells by acting on presynaptic GABA receptors. Suppressing GABA production or release from reactive astrocytes fully restores the impaired spike probability, synaptic plasticity, and learning and memory in the mice. In the postmortem brain of individuals with AD, astrocytic GABA and MAOB are significantly upregulated. We propose that selective inhibition of astrocytic GABA synthesis or release may serve as an effective therapeutic strategy for treating memory impairment in AD.
Spatial Impairment and Memory in Genetic Disorders: Insights from Mouse Models

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Sang Ah Lee

2017-02-01

Full Text Available Research across the cognitive and brain sciences has begun to elucidate some of the processes that guide navigation and spatial memory. Boundary geometry and featural landmarks are two distinct classes of environmental cues that have dissociable neural correlates in spatial representation and follow different patterns of learning. Consequently, spatial navigation depends both on the type of cue available and on the type of learning provided. We investigated this interaction between spatial representation and memory by administering two different tasks (working memory, reference memory using two different environmental cues (rectangular geometry, striped landmark in mouse models of human genetic disorders: Prader-Willi syndrome (PWScrm+/p− mice, n = 12 and Beta-catenin mutation (Thr653Lys-substituted mice, n = 12. This exploratory study provides suggestive evidence that these models exhibit different abilities and impairments in navigating by boundary geometry and featural landmarks, depending on the type of memory task administered. We discuss these data in light of the specific deficits in cognitive and brain function in these human syndromes and their animal model counterparts.
Whole brain radiation-induced impairments in learning and memory are time-sensitive and reversible by systemic hypoxia.

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Junie P Warrington

Full Text Available Whole brain radiation therapy (WBRT is commonly used for treatment of primary and metastatic brain tumors; however, cognitive impairment occurs in 40-50% of brain tumor survivors. The etiology of the cognitive impairment following WBRT remains elusive. We recently reported that radiation-induced cerebrovascular rarefaction within hippocampal subregions could be completely reversed by systemic hypoxia. However, the effects of this intervention on learning and memory have not been reported. In this study, we assessed the time-course for WBRT-induced impairments in contextual and spatial learning and the capacity of systemic hypoxia to reverse WBRT-induced deficits in spatial memory. A clinical fractionated series of 4.5Gy WBRT was administered to mice twice weekly for 4 weeks, and after various periods of recovery, behavioral analyses were performed. To study the effects of systemic hypoxia, mice were subjected to 11% (hypoxia or 21% oxygen (normoxia for 28 days, initiated 1 month after the completion of WBRT. Our results indicate that WBRT induces a transient deficit in contextual learning, disruption of working memory, and progressive impairment of spatial learning. Additionally, systemic hypoxia completely reversed WBRT-induced impairments in learning and these behavioral effects as well as increased vessel density persisted for at least 2 months following hypoxia treatment. Our results provide critical support for the hypothesis that cerebrovascular rarefaction is a key component of cognitive impairment post-WBRT and indicate that processes of learning and memory, once thought to be permanently impaired after WBRT, can be restored.
Verbal working memory in schizophrenia from the Consortium on the Genetics of Schizophrenia (COGS) study: the moderating role of smoking status and antipsychotic medications.

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Lee, Junghee; Green, Michael F; Calkins, Monica E; Greenwood, Tiffany A; Gur, Raquel E; Gur, Ruben C; Lazzeroni, Laura C; Light, Gregory A; Nuechterlein, Keith H; Radant, Allen D; Seidman, Larry J; Siever, Larry J; Silverman, Jeremy M; Sprock, Joyce; Stone, William S; Sugar, Catherine A; Swerdlow, Neal R; Tsuang, Debby W; Tsuang, Ming T; Turetsky, Bruce I; Braff, David L

2015-04-01

Working memory impairment has been extensively studied in schizophrenia, but less is known about moderators of the impairment. Using the Consortium on the Genetics of Schizophrenia case-control study (COGS-2), we examined smoking status, types of antipsychotic medication, and history of substance as moderators for working memory impairment in schizophrenia. From 5 sites, 1377 patients with schizophrenia or schizoaffective, depressed type and 1037 healthy controls completed the letter-number span (LNS) task. The LNS uses intermixed letter and digit stimuli that increase from 2 up to 8 stimuli. In the forward condition, participants repeated the letters and numbers in the order they were presented. In the reorder condition, participants repeated the digits in ascending order followed by letters in alphabetical order. Schizophrenia patients performed more poorly than controls, with a larger difference on reorder than forward conditions. Deficits were associated with symptoms, functional capacity, and functional outcome. Patients who smoked showed larger impairment than nonsmoking patients, primarily due to deficits on the reorder condition. The impairing association of smoking was more pronounced among patients taking first-generation than those taking second-generation antipsychotic medications. Correlations between working memory and community functioning were stronger for nonsmokers. History of substance use did not moderate working memory impairment. Results confirm the working memory impairment in schizophrenia, and indicate smoking status as an important moderator for these deficits. The greater impairment in smokers may reflect added burden of smoking on general health or that patients with greater deficits are more likely to smoke. Copyright © 2014 Elsevier B.V. All rights reserved.
Interaction of threat and verbal working memory in adolescents.

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Patel, Nilam; Vytal, Katherine; Pavletic, Nevia; Stoodley, Catherine; Pine, Daniel S; Grillon, Christian; Ernst, Monique

2016-04-01

Threat induces a state of sustained anxiety that can disrupt cognitive processing, and, reciprocally, cognitive processing can modulate an anxiety response to threat. These effects depend on the level of cognitive engagement, which itself varies as a function of task difficulty. In adults, we recently showed that induced anxiety impaired working memory accuracy at low and medium but not high load. Conversely, increasing the task load reduced the physiological correlates of anxiety (anxiety-potentiated startle). The present work examines such threat-cognition interactions as a function of age. We expected threat to more strongly impact working memory in younger individuals by virtue of putatively restricted cognitive resources and weaker emotion regulation. This was tested by examining the influence of age on the interaction of anxiety and working memory in 25 adolescents (10 to 17 years) and 25 adults (22 to 46 years). Working memory load was manipulated using a verbal n-back task. Anxiety was induced using the threat of an aversive loud scream and measured via eyeblink startle. Findings revealed that, in both age groups, accuracy was lower during threat than safe conditions at low and medium but not high load, and reaction times were faster during threat than safe conditions at high load but did not differ at other loads. Additionally, anxiety-potentiated startle was greater during low and medium than high load. Thus, the interactions of anxiety with working memory appear similar in adolescents and adults. Whether these similarities reflect common neural mechanisms would need to be assessed using functional neuroimaging. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Destination memory impairment in older people.

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Gopie, Nigel; Craik, Fergus I M; Hasher, Lynn

2010-12-01

Older adults are assumed to have poor destination memory-knowing to whom they tell particular information-and anecdotes about them repeating stories to the same people are cited as informal evidence for this claim. Experiment 1 assessed young and older adults' destination memory by having participants tell facts (e.g., "A dime has 118 ridges around its edge") to pictures of famous people (e.g., Oprah Winfrey). Surprise recognition memory tests, which also assessed confidence, revealed that older adults, compared to young adults, were disproportionately impaired on destination memory relative to spared memory for the individual components (i.e., facts, faces) of the episode. Older adults also were more confident that they had not told a fact to a particular person when they actually had (i.e., a miss); this presumably causes them to repeat information more often than young adults. When the direction of information transfer was reversed in Experiment 2, such that the famous people shared information with the participants (i.e., a source memory experiment), age-related memory differences disappeared. In contrast to the destination memory experiment, older adults in the source memory experiment were more confident than young adults that someone had shared a fact with them when a different person actually had shared the fact (i.e., a false alarm). Overall, accuracy and confidence jointly influence age-related changes to destination memory, a fundamental component of successful communication. (c) 2010 APA, all rights reserved).

Math anxiety and developmental dyscalculia: A study on working memory processes.

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Mammarella, Irene C; Hill, Francesca; Devine, Amy; Caviola, Sara; Szűcs, Dénes

2015-01-01

Although many children encounter difficulties in arithmetic, the underlying cognitive and emotive factors are still not fully understood. This study examined verbal and visuospatial short-term memory (STM) and working memory (WM) performance in children with developmental dyscalculia (DD) and high mathematics anxiety (MA) compared with typically developing (TD) children. Groups were matched on reading comprehension performance and IQ as well as on general anxiety. We aimed to test whether children with DD and MA were differently impaired in verbal and visuospatial STM and WM. Children were individually tested with four computerized tasks: two STM tasks (forward verbal and visuospatial recall) and two WM tasks (backward verbal and visuospatial recall). Relative to children with TD, those with DD did not show impairments on the forward or backward verbal tasks, but showed specific impairments in the visuospatial WM task. In contrast, children with MA were particularly impaired in the verbal WM task. Knowing the underlying cognitive processes that differentiate why children with DD and MA fail in math could have both educational and clinical implications.
Organizational strategies mediate nonverbal memory impairment in obsessive-compulsive disorder.

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Savage, C R; Baer, L; Keuthen, N J; Brown, H D; Rauch, S L; Jenike, M A

1999-04-01

Previous neuropsychological studies of obsessive-compulsive disorder (OCD) have indicated impaired executive functioning and nonverbal memory. The extent to which impaired executive functioning impacts nonverbal memory has not been established. The current study investigated the mediating effects of organizational strategies used when copying a figure on subsequent nonverbal memory for that figure. We examined neuropsychological performance in 20 unmedicated subjects with OCD and 20 matched normal control subjects. Subjects were administered the Rey-Osterrieth Complex Figure Test (RCFT) and neuropsychological tests assessing various aspects of executive function. OCD subjects differed significantly from healthy control subjects in the organizational strategies used to copy the RCFT figure, and they recalled significantly less information on both immediate and delayed testing. Multiple regression analyses indicated that group differences in immediate percent recall were significantly mediated by copy organizational strategies. Further exploratory analyses indicated that organizational problems in OCD may be related to difficulties shifting mental and/or spatial set. Immediate nonverbal memory problems in OCD subjects were mediated by impaired organizational strategies used during the initial copy of the RCFT figure. Thus, the primary deficit was one affecting executive function, which then had a secondary effect on immediate memory. These findings are consistent with current theories proposing frontal-striatal system dysfunction in OCD.
The Polarity-Dependent Effects of the Bilateral Brain Stimulation on Working Memory

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Fatemeh Keshvari

2013-08-01

Full Text Available Introduction: Working memory plays a critical role in cognitive processes which are central to our daily life. Neuroimaging studies have shown that one of the most important areas corresponding to the working memory is the dorsolateral prefrontal cortex (DLFPC. This study was aimed to assess whether bilateral modulation of the DLPFC using a noninvasive brain stimulation, namely transcranial direct current stimulation (tDCS, modi.es the working memory function in healthy adults.Methods: In a randomized sham-controlled cross-over study, 60 subjects (30 Males received sham and active tDCS in two subgroups (anode left/cathode right and anode right/cathode left of the DLPFC. Subjects were presented working memory n-back task while the reaction time and accuracy were recorded.Results: A repeated measures, mixed design ANOVA indicated a signi.cant difference between the type of stimulation (sham vs. active in anodal stimulation of the left DLPFC with cathodal stimulation of the right DLPFC [F(1,55= 5.29, P=0.019], but not the inverse polarity worsened accuracy in the 2-back working memory task. There were also no statistically signi.cant changes in speed of working memory [F(1,55= 0.458 ,P=0.502] related to type or order of stimulation..Discussion: The results would imply to a polarity dependence of bilateral tDCS of working memory. Left anodal/ right cathodal stimulation of DLPFC could impair working memory, while the reverser stimulation had no effect. Meaning that bilateral stimulation of DLFC would not be a useful procedure to improve working memory. Further studies are required to understand subtle effects of different tDCS stimulation/inhibition electrode positioning on the working memory.
Effect of a single dose of dextromethorphan on psychomotor performance and working memory capacity.

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Al-Kuraishy, Hayder M; Al-Gareeb, Ali I; Ashor, Ammar Waham

2012-04-01

Previous studies show that the prolonged use of dextromethorphan produces cognitive deterioration in humans. The aim of this study was to investigate the effect of a single dose of dextroemthrophan on psychomotor performance and working memory capacity. This is a randomized, double-blind, controlled, and prospective study. Thirty-six (17 women, 19 men) medical students enrolled in the study; half of them (7 women, 11 men) were given placebo, while the other half (10 women, 8 men) received dextromethorphan. The choice reaction time, critical flicker fusion threshold, and N-back working memory task were measured before and after 2 h of taking the drugs. Dextromethorphan showed a significant deterioration in the 3-back working memory task (P0.05). On the other hand, placebo showed no significant changes as regards the choice reaction time, critical flicker fusion threshold, and N-back working memory task (P>0.05). A single dose of dextromethorphan has no effect on attention and arousal but may significantly impair the working memory capacity.
Neuroprotective effect of curcumin on okadaic acid induced memory impairment in mice.

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Rajasekar, N; Dwivedi, Subhash; Tota, Santosh Kumar; Kamat, Pradeep Kumar; Hanif, Kashif; Nath, Chandishwar; Shukla, Rakesh

2013-09-05

Okadaic acid (OKA) has been observed to cause memory impairment in human subjects having seafood contaminated with dinoflagellate (Helicondria okadai). OKA induces tau hyperphosphorylation and oxidative stress leading to memory impairment as our previous study has shown. Curcumin a natural antioxidant has demonstrated neuroprotection in various models of neurodegeneration. However, the effect of curcumin has not been explored in OKA induced memory impairment. Therefore, present study evaluated the effect of curcumin on OKA (100ng, intracerebrally) induced memory impairment in male Swiss albino mice as evaluated in Morris water maze (MWM) and passive avoidance tests (PAT). OKA administration resulted in memory impairment with a decreased cerebral blood flow (CBF) (measured by laser doppler flowmetry), ATP level and increased mitochondrial (Ca(2+))i, neuroinflammation (increased TNF-α, IL-1β, COX-2 and GFAP), oxidative-nitrosative stress, increased Caspase-9 and cholinergic dysfunction (decreased AChE activity/expression and α7 nicotinic acetylcholine receptor expression) in cerebral cortex and hippocampus of mice brain. Oral administration of curcumin (50mg/kg) for 13 days significantly improved memory function in both MWM and PAT along with brain energy metabolism, CBF and cholinergic function. It decreased mitochondrial (Ca(2+))i, and ameliorated neuroinflammation and oxidative-nitrostative stress in different brain regions of OKA treated mice. Curcumin also inhibited astrocyte activation as evidenced by decreased GFAP expression. This neuroprotective effect of curcumin is due to its potent anti-oxidant action thus confirming previous studies. Therefore, use of curcumin should be encouraged in people consuming sea food (contaminated with dinoflagellates) to prevent cognitive impairment. © 2013 Elsevier B.V. All rights reserved.
Selective dentate gyrus disruption causes memory impairment at the early stage of experimental multiple sclerosis.

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Planche, Vincent; Panatier, Aude; Hiba, Bassem; Ducourneau, Eva-Gunnel; Raffard, Gerard; Dubourdieu, Nadège; Maitre, Marlène; Lesté-Lasserre, Thierry; Brochet, Bruno; Dousset, Vincent; Desmedt, Aline; Oliet, Stéphane H; Tourdias, Thomas

2017-02-01

Memory impairment is an early and disabling manifestation of multiple sclerosis whose anatomical and biological substrates are still poorly understood. We thus investigated whether memory impairment encountered at the early stage of the disease could be explained by a differential vulnerability of particular hippocampal subfields. By using experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis, we identified that early memory impairment was associated with selective alteration of the dentate gyrus as pinpointed in vivo with diffusion-tensor-imaging (DTI). Neuromorphometric analyses and electrophysiological recordings confirmed dendritic degeneration, alteration in glutamatergic synaptic transmission and impaired long-term synaptic potentiation selectively in the dentate gyrus, but not in CA1, together with a more severe pattern of microglial activation in this subfield. Systemic injections of the microglial inhibitor minocycline prevented DTI, morphological, electrophysiological and behavioral impairments in EAE-mice. Furthermore, daily infusions of minocycline specifically within the dentate gyrus were sufficient to prevent memory impairment in EAE-mice while infusions of minocycline within CA1 were inefficient. We conclude that early memory impairment in EAE is due to a selective disruption of the dentate gyrus associated with microglia activation. These results open new pathophysiological, imaging, and therapeutic perspectives for memory impairment in multiple sclerosis. Copyright © 2016 Elsevier Inc. All rights reserved.
Functional MR imaging of working memory before neurosurgery; Funktionelle MR-Bildgebung des Arbeitsgedaechtnisses vor neurochirurgischen Eingriffen

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Wunderlich, A.P. [Abt. Diagnostische Radiologie, Universitaetsklinikum Ulm (Germany); Groen, G. [Abt. Psychiatrie III, Universitaetsklinikum Ulm (Germany); Braun, V. [Neurochirurgie, Ev. Jung-Stilling-Krankenhaus Siegen (Germany)

2007-07-01

Information concerning the tissue adjacent to a brain tumour is crucial for planning and performing a neurosurgical intervention. In this study, we evaluated the usefulness of functional imaging of working memory in terms of working memory preservation. Working memory performance of 14 patients with prefrontal tumours was tested preoperatively by means of a standardized neuropsychological test battery. Also, functional magnetic resonance imaging (fMRI) using a so-called two-back paradigm was performed to visualize brain areas related to that task. Working memory areas were reliably detected in all patients. Surgery was then planned on the basis of this information, and the data were used for intra-operative cranial neuronavigation. Three to twelve months after surgery, patients were tested again with the test battery in order to detect possible changes in working memory performance. In 13 cases the memory performance was unchanged, only one female patient had a slight impairment of working memory compared to the pre-operative status. (orig.)
Cordyceps militaris extract attenuates D-galactose-induced memory impairment in mice.

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Li, Zaixin; Zhang, Zhi; Zhang, Jinshan; Jia, Jing; Ding, Jie; Luo, Rongzhen; Liu, Zhangqin

2012-12-01

Memory impairment is one of main clinical symptoms of brain senescence. To address the effects of Cordyceps militaris Link extract (CE) on memory impairment, a D-galactose (D-Gal)-induced aging mouse model was employed. Mice injected with D-Gal showed a significant learning and memory impairment that was rescued by CE treatment. The mechanism was further investigated by analyzing the protein level and activity of oxidant and antioxidant molecules, including malondialdehyde (MDA), monoamine oxidase (MAO), total super-oxide dismutase (T-SOD), total antioxidant capacity (T-AOC), glutathione (GSH), and glutathione peroxidase (GSH-px), which played critical roles in the development of brain senescence. The results showed that CE treatment resulted in a significant decrease in the oxidative activity of MAO and the level of MDA, and significantly increased the antioxidant activities of T-SOD and T-AOC in the cerebral cortices. Moreover, the level of GSH and the activity of antioxidant enzymes GSH-px in serum were significantly upregulated after CE treatment. Taken together, our results suggest that Cordyceps militaris extract could ameliorate experimental memory impairment in mice with D-Gal-induced aging through its potent antioxidant activities.
Inhibiting the Mitochondrial Calcium Uniporter during Development Impairs Memory in Adult Drosophila

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Ilaria Drago

2016-09-01

Full Text Available The uptake of cytoplasmic calcium into mitochondria is critical for a variety of physiological processes, including calcium buffering, metabolism, and cell survival. Here, we demonstrate that inhibiting the mitochondrial calcium uniporter in the Drosophila mushroom body neurons (MBn—a brain region critical for olfactory memory formation—causes memory impairment without altering the capacity to learn. Inhibiting uniporter activity only during pupation impaired adult memory, whereas the same inhibition during adulthood was without effect. The behavioral impairment was associated with structural defects in MBn, including a decrease in synaptic vesicles and an increased length in the axons of the αβ MBn. Our results reveal an in vivo developmental role for the mitochondrial uniporter complex in establishing the necessary structural and functional neuronal substrates for normal memory formation in the adult organism.
No functional role of attention-based rehearsal in maintenance of spatial working memory representations.

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Belopolsky, Artem V; Theeuwes, Jan

2009-10-01

The present study systematically examined the role of attention in maintenance of spatial representations in working memory as proposed by the attention-based rehearsal hypothesis [Awh, E., Jonides, J., & Reuter-Lorenz, P. A. (1998). Rehearsal in spatial working memory. Journal of Experimental Psychology--Human Perception and Performance, 24(3), 780-790]. Three main issues were examined. First, Experiments 1-3 demonstrated that inhibition and not facilitation of visual processing is often observed at the memorized location during the retention interval. This inhibition was caused by keeping a location in memory and not by the exogenous nature of the memory cue. Second, Experiment 4 showed that inhibition of the memorized location does not lead to any significant impairment in memory accuracy. Finally, Experiment 5 connected current results to the previous findings and demonstrated facilitation of processing at the memorized location. Importantly, facilitation of processing did not lead to more accurate memory performance. The present results challenge the functional role of attention in maintenance of spatial working memory representations.
Hippocampal Administration of Levothyroxine Impairs Contextual Fear Memory Consolidation in Rats.

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Yu, Dafu; Zhou, Heng; Zou, Lin; Jiang, Yong; Wu, Xiaoqun; Jiang, Lizhu; Zhou, Qixin; Yang, Yuexiong; Xu, Lin; Mao, Rongrong

2017-01-01

Thyroid hormone (TH) receptors are highly distributed in the hippocampus, which plays a vital role in memory processes. However, how THs are involved in the different stages of memory process is little known. Herein, we used hippocampus dependent contextual fear conditioning to address the effects of hippocampal THs on the different stages of fear memory. First, we found that a single systemic levothyroxine (LT 4 ) administration increased the level of free triiodothyronine (FT 3 ) and free tetraiodothyroxine (FT 4 ) not only in serum but also in hippocampus. In addition, a single systemic LT 4 administration immediately after fear conditioning significantly impaired fear memory. These results indicated the important role of hippocampal THs in fear memory process. To further confirm the effects of hippocampal THs on the different stages of fear memory, LT 4 (0.4 μg/μl, 1 μl/side) was injected bilaterally into hippocampus. Rats given LT 4 into hippocampus before training or tests had no effect on the acquisition or retrieval of fear memory, however rats given LT 4 into hippocampus either immediately or 2 h after training showed being significantly impaired fear memory, which demonstrated LT 4 administration into hippocampus impairs the consolidation but has no effect on the acquisition and retrieval of fear memory. Furthermore, hippocampal injection of LT 4 did not affect rats' locomotor activity, thigmotaxis and THs level in prefrontal cortex (PFC) and serum. These findings may have important implications for understanding mechanisms underlying contribution of THs to memory disorders.
Age-Related Decline of Precision and Binding in Visual Working Memory

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2013-01-01

Working memory declines with normal aging, but the nature of this impairment is debated. Studies based on detecting changes to arrays of visual objects have identified two possible components to age-related decline: a reduction in the number of items that can be stored, or a deficit in maintaining the associations (bindings) between individual object features. However, some investigations have reported intact binding with aging, and specific deficits arising only in Alzheimer’s disease. Here, using a recently developed continuous measure of recall fidelity, we tested the precision with which adults of different ages could reproduce from memory the orientation and color of a probed array item. The results reveal a further component of cognitive decline: an age-related decrease in the resolution with which visual information can be maintained in working memory. This increase in recall variability with age was strongest under conditions of greater memory load. Moreover, analysis of the distribution of errors revealed that older participants were more likely to incorrectly report one of the unprobed items in memory, consistent with an age-related increase in misbinding. These results indicate a systematic decline with age in working memory resources that can be recruited to store visual information. The paradigm presented here provides a sensitive index of both memory resolution and feature binding, with the potential for assessing their modulation by interventions. The findings have implications for understanding the mechanisms underpinning working memory deficits in both health and disease. PMID:23978008
Integrated cross-domain object storage in working memory: evidence from a verbal-spatial memory task.

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Morey, Candice C

2009-11-01

Working-memory theories often include domain-specific verbal and visual stores (e.g., the phonological and visuospatial buffers of Baddeley, 1986), and some also posit more general stores thought to be capable of holding verbal or visuospatial materials (Baddeley, 2000; Cowan, 2005). However, it is currently unclear which type of store is primarily responsible for maintaining objects that include components from multiple domains. In these studies, a spatial array of letters was followed by a single probe identical to an item in the array or differing systematically in spatial location, letter identity, or their combination. Concurrent verbal rehearsal suppression impaired memory in each of these trial types in a task that required participants to remember verbal-spatial binding, but did not impair memory for spatial locations if the task did not require verbal-spatial binding for a correct response. Thus, spatial information might be stored differently when it must be bound to verbal information. This suggests that a cross-domain store such as the episodic buffer of Baddeley (2000) or the focus of attention of Cowan (2001) might be used for integrated object storage, rather than the maintenance of associations between features stored in separate domain-specific buffers.
Symmetry and binding in visuo-spatial working memory.

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Rossi-Arnaud, C; Pieroni, L; Baddeley, A

2006-04-28

Three experiments study the impact of symmetry on a sequential block tapping immediate memory task in human subjects. Experiment 1 shows an advantage from vertical symmetry over non-symmetrical sequences, while finding no effect of horizontal or diagonal symmetry. Experiment 2 tests the possible role of verbal labeling by means of a secondary task that prevents this by articulatory suppression. No evidence of verbalization was observed. A third study examines the effects of a concurrent executive load, finding an overall impairment, that did not differ between symmetrical and asymmetric patterns, suggesting that the effect of symmetry reflects automatic rather than executive processes. Implications for the episodic buffer component of working memory are discussed.
Working memory for visual features and conjunctions in schizophrenia.

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Gold, James M; Wilk, Christopher M; McMahon, Robert P; Buchanan, Robert W; Luck, Steven J

2003-02-01

The visual working memory (WM) storage capacity of patients with schizophrenia was investigated using a change detection paradigm. Participants were presented with 2, 3, 4, or 6 colored bars with testing of both single feature (color, orientation) and feature conjunction conditions. Patients performed significantly worse than controls at all set sizes but demonstrated normal feature binding. Unlike controls, patient WM capacity declined at set size 6 relative to set size 4. Impairments with subcapacity arrays suggest a deficit in task set maintenance: Greater impairment for supercapacity set sizes suggests a deficit in the ability to selectively encode information for WM storage. Thus, the WM impairment in schizophrenia appears to be a consequence of attentional deficits rather than a reduction in storage capacity.
The contributions of handedness and working memory to episodic memory.

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Sahu, Aparna; Christman, Stephen D; Propper, Ruth E

2016-11-01

Past studies have independently shown associations of working memory and degree of handedness with episodic memory retrieval. The current study takes a step ahead by examining whether handedness and working memory independently predict episodic memory. In agreement with past studies, there was an inconsistent-handed advantage for episodic memory; however, this advantage was absent for working memory tasks. Furthermore, regression analyses showed handedness, and complex working memory predicted episodic memory performance at different times. Results are discussed in light of theories of episodic memory and hemispheric interaction.
Executive Functions and Working Memory Behaviours in Children with a Poor Working Memory

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St. Clair-Thompson, Helen L.

2011-01-01

Previous research has suggested that working memory difficulties play an integral role in children's underachievement at school. However, working memory is just one of several executive functions. The extent to which problems in working memory extend to other executive functions is not well understood. In the current study 38 children with a poor…
Amyloid-independent functional neural correlates of episodic memory in amnestic mild cognitive impairment.

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Seo, Eun Hyun; Choo, I L Han

2016-06-01

Although amnestic mild cognitive impairment (aMCI) could have various biological characteristics, little attention has been given to the nature of episodic memory decline in aMCI with pathophysiologies other than Alzheimer's disease (AD), i.e., aMCI with low beta-amyloid (Aβ) burden. This study aimed to identify the functional neural basis of episodic memory impairment in aMCI with Aβ burden negative (aMCI-Aβ-) and to compare these results with aMCI with Aβ burden positive (aMCI-Aβ+). Individuals with aMCI (n = 498) were selected from the Alzheimer's Disease Neuroimaging Initiative database. Based on the mean florbetapir standard uptake value ratio, participants were classified as aMCI-Aβ- or aMCI-Aβ+. Correlations between memory scores and regional cerebral glucose metabolism (rCMglc) were analyzed separately for the two subgroups using a multiple regression model. For aMCI-Aβ-, significant positive correlations between memory and rCMglc were found in the bilateral claustrum, right thalamus, left anterior cingulate cortex, left insula, and right posterior cingulate. For aMCI-Aβ+, significant positive correlations between memory and rCMglc were found in the temporoparietal areas. These correlation patterns remained unchanged when clinical severity was added as a covariate Our findings indicate that memory impairment in aMCI-Aβ- is related to multimodal integrative processing and the attentional control system, whereas memory impairment in aMCI-Aβ+ is related to the typical brain memory systems and AD signature. These results suggest that although the two subgroups are clinically in the same category as aMCI, the memory impairment process depends on completely different functional brain regions according to their Aβ burden level.
Source Memory for Self and Other in Patients With Mild Cognitive Impairment due to Alzheimer's Disease.

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Rosa, Nicole M; Deason, Rebecca G; Budson, Andrew E; Gutchess, Angela H

2016-01-01

The present study examined the role of enactment in source memory in a cognitively impaired population. As seen in healthy older adults, it was predicted that source memory in people with mild cognitive impairment due to Alzheimer's disease (MCI-AD) would benefit from the self-reference aspect of enactment. Seventeen participants with MCI-AD and 18 controls worked in small groups to pack a picnic basket and suitcase and were later tested for their source memory for each item. For item memory, self-referencing improved corrected recognition scores for both MCI-AD and control participants. The MCI-AD group did not demonstrate the same benefit as controls in correct source memory for self-related items. However, those with MCI-AD were relatively less likely to misattribute new items to the self and more likely to misattribute new items to others when committing errors, compared with controls. The enactment effect and self-referencing did not enhance accurate source memory more than other referencing for patients with MCI-AD. However, people with MCI-AD benefited in item memory and source memory, being less likely to falsely claim new items as their own, indicating some self-reference benefit occurs for people with MCI-AD. Published by Oxford University Press on behalf of the Gerontological Society of America 2014.
Is the link from working memory to analogy causal? No analogy improvements following working memory training gains.

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J Elizabeth Richey

Full Text Available Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data, but less work has tested this relationship through experimental manipulation. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants' performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks. Participants' improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning.

Is the link from working memory to analogy causal? No analogy improvements following working memory training gains.

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Richey, J Elizabeth; Phillips, Jeffrey S; Schunn, Christian D; Schneider, Walter

2014-01-01

Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data, but less work has tested this relationship through experimental manipulation. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants' performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks. Participants' improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning.
Is the Link from Working Memory to Analogy Causal? No Analogy Improvements following Working Memory Training Gains

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Richey, J. Elizabeth; Phillips, Jeffrey S.; Schunn, Christian D.; Schneider, Walter

2014-01-01

Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data [1], but less work has tested this relationship through experimental manipulation [2]. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants’ performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks [3], [4]. Participants’ improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning. PMID:25188356
Memory deficits in amyotrophic lateral sclerosis are not exclusively caused by executive dysfunction: a comparative neuropsychological study of amnestic mild cognitive impairment.

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Machts, Judith; Bittner, Verena; Kasper, Elisabeth; Schuster, Christina; Prudlo, Johannes; Abdulla, Susanne; Kollewe, Katja; Petri, Susanne; Dengler, Reinhard; Heinze, Hans-Jochen; Vielhaber, Stefan; Schoenfeld, Mircea A; Bittner, Daniel M

2014-06-30

Recent work suggests that ALS and frontotemporal dementia can occur together and share at least in part the same underlying pathophysiology. However, it is unclear at present whether memory deficits in ALS stem from a temporal lobe dysfunction, or are rather driven by frontal executive dysfunction. In this study we sought to investigate the nature of memory deficits by analyzing the neuropsychological performance of 40 ALS patients in comparison to 39 amnestic mild cognitive impairment (aMCI) patients and 40 healthy controls (HC). The neuropsychological battery tested for impairment in executive functions, as well as memory and visuo-spatial skills, the results of which were compared across study groups. In addition, we calculated composite scores for memory (learning, recall, recognition) and executive functions (verbal fluency, cognitive flexibility, working memory). We hypothesized that the nature of memory impairment in ALS will be different from those exhibited by aMCI patients. Patient groups exhibited significant differences in their type of memory deficit, with the ALS group showing impairment only in recognition, whereas aMCI patients showed short and delayed recall performance deficits as well as reduced short-term capacity. Regression analysis revealed a significant impact of executive function on memory performance exclusively for the ALS group, accounting for one fifth of their memory performance. Interestingly, merging all sub scores into a single memory and an executive function score obscured these differences. The presented results indicate that the interpretation of neuropsychological scores needs to take the distinct cognitive profiles in ALS and aMCI into consideration. Importantly, the observed memory deficits in ALS were distinctly different from those observed in aMCI and can be explained only to some extent in the context of comorbid (coexisting) executive dysfunction. These findings highlight the qualitative differences in temporal lobe
Detailed sensory memory, sloppy working memory

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Sligte, I.G.; Vandenbroucke, A.R.E.; Scholte, H.S.; Lamme, V.A.F.

2010-01-01

Visual short-term memory (VSTM) enables us to actively maintain information in mind for a brief period of time after stimulus disappearance. According to recent studies, VSTM consists of three stages - iconic memory, fragile VSTM, and visual working memory - with increasingly stricter capacity
Pridopidine Reverses Phencyclidine-Induced Memory Impairment.

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Sahlholm, Kristoffer; Valle-León, Marta; Fernández-Dueñas, Víctor; Ciruela, Francisco

2018-01-01

Pridopidine is in clinical trials for Huntington's disease treatment. Originally developed as a dopamine D 2 receptor (D 2 R) ligand, pridopidine displays about 100-fold higher affinity for the sigma-1 receptor (sigma-1R). Interestingly, pridopidine slows disease progression and improves motor function in Huntington's disease model mice and, in preliminarily reports, Huntington's disease patients. The present study examined the anti-amnesic potential of pridopidine. Thus, memory impairment was produced in mice by administration of phencyclidine (PCP, 10 mg/kg/day) for 10 days, followed by 14 days' treatment with pridopidine (6 mg/kg/day), or saline. Finally, novel object recognition performance was assessed in the animals. Mice receiving PCP and saline exhibited deficits in novel object recognition, as expected, while pridopidine treatment counteracted PCP-induced memory impairment. The effect of pridopidine was attenuated by co-administration of the sigma receptor antagonist, NE-100 (10 mg/kg). Our results suggest that pridopidine exerts anti-amnesic and potentially neuroprotective actions. These data provide new insights into the therapeutic potential of pridopidine as a pro-cognitive drug.
Neurocognitive architecture of working memory

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Eriksson, Johan; Vogel, Edward K.; Lansner, Anders; Bergström, Fredrik; Nyberg, Lars

2015-01-01

The crucial role of working memory for temporary information processing and guidance of complex behavior has been recognized for many decades. There is emerging consensus that working memory maintenance results from the interactions among long-term memory representations and basic processes, including attention, that are instantiated as reentrant loops between frontal and posterior cortical areas, as well as subcortical structures. The nature of such interactions can account for capacity limitations, lifespan changes, and restricted transfer after working-memory training. Recent data and models indicate that working memory may also be based on synaptic plasticity, and that working memory can operate on non-consciously perceived information. PMID:26447571
Reduced Mastication Impairs Memory Function.

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Fukushima-Nakayama, Y; Ono, Takehito; Hayashi, M; Inoue, M; Wake, H; Ono, Takashi; Nakashima, T

2017-08-01

Mastication is an indispensable oral function related to physical, mental, and social health throughout life. The elderly tend to have a masticatory dysfunction due to tooth loss and fragility in the masticatory muscles with aging, potentially resulting in impaired cognitive function. Masticatory stimulation has influence on the development of the central nervous system (CNS) as well as the growth of maxillofacial tissue in children. Although the relationship between mastication and cognitive function is potentially important in the growth period, the cellular and molecular mechanisms have not been sufficiently elucidated. Here, we show that the reduced mastication resulted in impaired spatial memory and learning function owing to the morphological change and decreased activity in the hippocampus. We used an in vivo model for reduced masticatory stimuli, in which juvenile mice were fed with powder diet and found that masticatory stimulation during the growth period positively regulated long-term spatial memory to promote cognitive function. The functional linkage between mastication and brain was validated by the decrease in neurons, neurogenesis, neuronal activity, and brain-derived neurotrophic factor (BDNF) expression in the hippocampus. These findings taken together provide in vivo evidence for a functional linkage between mastication and cognitive function in the growth period, suggesting a need for novel therapeutic strategies in masticatory function-related cognitive dysfunction.
Memory systems interaction in the pigeon: working and reference memory.

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Roberts, William A; Strang, Caroline; Macpherson, Krista

2015-04-01

Pigeons' performance on a working memory task, symbolic delayed matching-to-sample, was used to examine the interaction between working memory and reference memory. Reference memory was established by training pigeons to discriminate between the comparison cues used in delayed matching as S+ and S- stimuli. Delayed matching retention tests then measured accuracy when working and reference memory were congruent and incongruent. In 4 experiments, it was shown that the interaction between working and reference memory is reciprocal: Strengthening either type of memory leads to a decrease in the influence of the other type of memory. A process dissociation procedure analysis of the data from Experiment 4 showed independence of working and reference memory, and a model of working memory and reference memory interaction was shown to predict the findings reported in the 4 experiments. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
Synaptic Effects of Dopamine Breakdown and Their Relation to Schizophrenia-Linked Working Memory Deficits

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Andrew D. Bolton

2018-06-01

Full Text Available Working memory is the ability to hold information “online” over a time delay in order to perform a task. This kind of memory is encoded in the brain by persistent neural activity that outlasts the presentation of a stimulus. Patients with schizophrenia perform poorly in working memory tasks that require the brief memory of a target location in space. This deficit indicates that persistent neural activity related to spatial locations may be impaired in the disease. At the circuit level, many studies have shown that NMDA receptors and the dopamine system are involved in both schizophrenia pathology and working memory-related persistent activity. In this Hypothesis and Theory article, we examine the possible connection between NMDA receptors, the dopamine system, and schizophrenia-linked working memory deficits. In particular, we focus on the dopamine breakdown product homocysteine (HCY, which is consistently elevated in schizophrenia patients. Our previous studies have shown that HCY strongly reduces the desensitization of NMDA currents. Here, we show that HCY likely affects NMDA receptors in brain regions that support working memory; this is because these areas favor dopamine breakdown over transport to clear dopamine from synapses. Finally, within the context of two NMDA-based computational models of working memory, we suggest a mechanism by which HCY could give rise to the working memory deficits observed in schizophrenia patients.
The impact of auditory working memory training on the fronto-parietal working memory network.

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Schneiders, Julia A; Opitz, Bertram; Tang, Huijun; Deng, Yuan; Xie, Chaoxiang; Li, Hong; Mecklinger, Axel

2012-01-01

Working memory training has been widely used to investigate working memory processes. We have shown previously that visual working memory benefits only from intra-modal visual but not from across-modal auditory working memory training. In the present functional magnetic resonance imaging study we examined whether auditory working memory processes can also be trained specifically and which training-induced activation changes accompany theses effects. It was investigated whether working memory training with strongly distinct auditory materials transfers exclusively to an auditory (intra-modal) working memory task or whether it generalizes to a (across-modal) visual working memory task. We used adaptive n-back training with tonal sequences and a passive control condition. The memory training led to a reliable training gain. Transfer effects were found for the (intra-modal) auditory but not for the (across-modal) visual transfer task. Training-induced activation decreases in the auditory transfer task were found in two regions in the right inferior frontal gyrus. These effects confirm our previous findings in the visual modality and extents intra-modal effects in the prefrontal cortex to the auditory modality. As the right inferior frontal gyrus is frequently found in maintaining modality-specific auditory information, these results might reflect increased neural efficiency in auditory working memory processes. Furthermore, task-unspecific (amodal) activation decreases in the visual and auditory transfer task were found in the right inferior parietal lobule and the superior portion of the right middle frontal gyrus reflecting less demand on general attentional control processes. These data are in good agreement with amodal activation decreases within the same brain regions on a visual transfer task reported previously.
The impact of auditory working memory training on the fronto-parietal working memory network

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Schneiders, Julia A.; Opitz, Bertram; Tang, Huijun; Deng, Yuan; Xie, Chaoxiang; Li, Hong; Mecklinger, Axel

2012-01-01

Working memory training has been widely used to investigate working memory processes. We have shown previously that visual working memory benefits only from intra-modal visual but not from across-modal auditory working memory training. In the present functional magnetic resonance imaging study we examined whether auditory working memory processes can also be trained specifically and which training-induced activation changes accompany theses effects. It was investigated whether working memory training with strongly distinct auditory materials transfers exclusively to an auditory (intra-modal) working memory task or whether it generalizes to a (across-modal) visual working memory task. We used adaptive n-back training with tonal sequences and a passive control condition. The memory training led to a reliable training gain. Transfer effects were found for the (intra-modal) auditory but not for the (across-modal) visual transfer task. Training-induced activation decreases in the auditory transfer task were found in two regions in the right inferior frontal gyrus. These effects confirm our previous findings in the visual modality and extents intra-modal effects in the prefrontal cortex to the auditory modality. As the right inferior frontal gyrus is frequently found in maintaining modality-specific auditory information, these results might reflect increased neural efficiency in auditory working memory processes. Furthermore, task-unspecific (amodal) activation decreases in the visual and auditory transfer task were found in the right inferior parietal lobule and the superior portion of the right middle frontal gyrus reflecting less demand on general attentional control processes. These data are in good agreement with amodal activation decreases within the same brain regions on a visual transfer task reported previously. PMID:22701418
Working-memory consolidation : Insights from studies on attention and working memory

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Ricker, Timothy; Nieuwenstein, Mark; Bayliss, Donna; Barrouillet, Pierre

2018-01-01

Working memory, the system that maintains a limited set of representations for immediate use in cognition, is a central part of human cognition. Three processes have recently been proposed to govern information storage in working memory: Consolidation, refreshing and removal. Here we discuss in
Expertise for upright faces improves the precision but not the capacity of visual working memory.

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Lorenc, Elizabeth S; Pratte, Michael S; Angeloni, Christopher F; Tong, Frank

2014-10-01

Considerable research has focused on how basic visual features are maintained in working memory, but little is currently known about the precision or capacity of visual working memory for complex objects. How precisely can an object be remembered, and to what extent might familiarity or perceptual expertise contribute to working memory performance? To address these questions, we developed a set of computer-generated face stimuli that varied continuously along the dimensions of age and gender, and we probed participants' memories using a method-of-adjustment reporting procedure. This paradigm allowed us to separately estimate the precision and capacity of working memory for individual faces, on the basis of the assumptions of a discrete capacity model, and to assess the impact of face inversion on memory performance. We found that observers could maintain up to four to five items on average, with equally good memory capacity for upright and upside-down faces. In contrast, memory precision was significantly impaired by face inversion at every set size tested. Our results demonstrate that the precision of visual working memory for a complex stimulus is not strictly fixed but, instead, can be modified by learning and experience. We find that perceptual expertise for upright faces leads to significant improvements in visual precision, without modifying the capacity of working memory.
Perinatal supplementation with omega-3 polyunsaturated fatty acids improves sevoflurane-induced neurodegeneration and memory impairment in neonatal rats.

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Xi Lei

Full Text Available OBJECTIVES: To investigate if perinatal Omega-3 polyunsaturated fatty acids (n-3 PUFAs supplementation can improve sevoflurane-induced neurotoxicity and cognitive impairment in neonatal rats. METHODS: Female Sprague-Dawley rats (n = 3 each group were treated with or without an n-3 PUFAs (fish oil enriched diet from the second day of pregnancy to 14 days after parturition. The offspring rats (P7 were treated with six hours sevoflurane administration (one group without sevoflurane/prenatal n-3 PUFAs supplement as control. The 5-bromodeoxyuridine (Brdu was injected intraperitoneally during and after sevoflurane anesthesia to assess dentate gyrus (DG progenitor proliferation. Brain tissues were harvested and subjected to Western blot and immunohistochemistry respectively. Morris water maze spatial reference memory, fear conditioning, and Morris water maze memory consolidation were tested at P35, P63 and P70 (n = 9, respectively. RESULTS: Six hours 3% sevoflurane administration increased the cleaved caspase-3 in the thalamus, parietal cortex but not hippocampus of neonatal rat brain. Sevoflurane anesthesia also decreased the neuronal precursor proliferation of DG in rat hippocampus. However, perinatal n-3 PUFAs supplement could decrease the cleaved caspase-3 in the cerebral cortex of neonatal rats, and mitigate the decrease in neuronal proliferation in their hippocampus. In neurobehavioral studies, compared with control and n-3 PUFAs supplement groups, we did not find significant spatial cognitive deficit and early long-term memory impairment in sevoflurane anesthetized neonatal rats at their adulthood. However, sevoflurane could impair the immediate fear response and working memory and short-term memory. And n-3 PUFAs could improve neurocognitive function in later life after neonatal sevoflurane exposure. CONCLUSION: Our study demonstrated that neonatal exposure to prolonged sevoflurane could impair the immediate fear response, working
The Acceptability and Potential Utility of Cognitive Training to Improve Working Memory in Persons Living With HIV: A Preliminary Randomized Trial.

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Towe, Sheri L; Patel, Puja; Meade, Christina S

HIV-associated neurocognitive impairments that impact daily function persist in the era of effective antiretroviral therapy. Cognitive training, a promising low-cost intervention, has been shown to improve neurocognitive functioning in some clinical populations. We tested the feasibility, acceptability, and preliminary effects of computerized cognitive training to improve working memory in persons living with HIV infection (PLWH) and working memory impairment. In this randomized clinical trial, we assigned 21 adult PLWH to either an experimental cognitive training intervention or an attention-matched control training intervention. Participants completed 12 training sessions across 10 weeks with assessments at baseline and post-training. Session attendance was excellent and participants rated the program positively. Participants in the experimental arm demonstrated improved working memory function over time; participants in the control arm showed no change. Our results suggest that cognitive training may be a promising intervention for working memory impairment in PLWH and should be evaluated further. Copyright © 2017 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.
Memory impairment due to fipronil pesticide exposure occurs at the GABAA receptor level, in rats.

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Godinho, Antonio Francisco; de Oliveira Souza, Ana Carolina; Carvalho, Caio Cristóvão; Horta, Daniel França; De Fraia, Daniel; Anselmo, Fabio; Chaguri, João Leandro; Faria, Caique Aparecido

2016-10-15

Fipronil (F) a pesticide considered of second generation cause various toxic effects in target and non-target organisms including humans in which provoke neurotoxicity, having the antagonism of gamma-amino butyric acid (GABA) as their main mechanism for toxic action. GABAergic system has been involved in processes related to the memory formation and consolidation. The present work studied the importance of GABA to the mechanisms involved in the very early development of fipronil-induced memory impairment in rats. Memory behavior was assessed using new object recognition task (ORT) and eight radial arm maze task (8-RAM) to study effects on cognitive and spatial memory. Locomotor behavior was assessed using open field task (OF). The dose of fipronil utilized was studied through a pilot experiment. The GABA antagonist picrotoxin (P) was used to enhance fipronil effects on GABAergic system. Fipronil or picrotoxin decrease memory studied in ORT and 8-RAM tasks. Additionally, F and P co-exposure enhanced effects on memory compared to controls, F, and P, suggesting strongly a GABAergic effect. Weight gain modulation and fipronil in blood were utilized as animal's intoxication indicators. In conclusion, here we report that second-generation pesticides, such as fipronil, can have toxic interactions with the CNS of mammals and lead to memory impairment by modulating the GABAergic system. Copyright © 2016 Elsevier Inc. All rights reserved.
The effects of centrally administered fluorocitrate via inhibiting glial cells on working memory in rats

Institute of Scientific and Technical Information of China (English)

无

2009-01-01

Although prefrontal and hippocampal neurons are critical for spatial working memory,the function of glial cells in spatial working memory remains uncertain.In this study we investigated the function of glial cells in rats’ working memory.The glial cells of rat brain were inhibited by intracerebroventricular(icv) injection of fluorocitrate(FC).The effects of FC on the glial cells were examined by using electroencephalogram(EEG) recordings and delayed spatial alternation tasks.After icv injection of 10 μL of 0.5 nmol/L or 5 nmol/L FC,the EEG power spectrum recorded from the hippocampus increased,but the power spectrum for the prefrontal cortex did not change,and working memory was unaffected.Following an icv injection of 10 μL of 20 nmol/L FC,the EEG power spectra in both the prefrontal cortex and the hippocampus increased,and working memory improved.The icv injection of 10 μL of 50 nmol/L FC,the EEG power spectra in both the prefrontal cortex and in the hippocampus decreased,and working memory was impaired.These results suggest that spatial working memory is affected by centrally administered FC,but only if there are changes in the EEG power spectrum in the prefrontal cortex.Presumably,the prefrontal glial cells relate to the working memory.
Amyloid β Enhances Typical Rodent Behavior While It Impairs Contextual Memory Consolidation.

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Salgado-Puga, Karla; Prado-Alcalá, Roberto A; Peña-Ortega, Fernando

2015-01-01

Alzheimer's disease (AD) is associated with an early hippocampal dysfunction, which is likely induced by an increase in soluble amyloid beta peptide (Aβ). This hippocampal failure contributes to the initial memory deficits observed both in patients and in AD animal models and possibly to the deterioration in activities of daily living (ADL). One typical rodent behavior that has been proposed as a hippocampus-dependent assessment model of ADL in mice and rats is burrowing. Despite the fact that AD transgenic mice show some evidence of reduced burrowing, it has not been yet determined whether or not Aβ can affect this typical rodent behavior and whether this alteration correlates with the well-known Aβ-induced memory impairment. Thus, the purpose of this study was to test whether or not Aβ affects burrowing while inducing hippocampus-dependent memory impairment. Surprisingly, our results show that intrahippocampal application of Aβ increases burrowing while inducing memory impairment. We consider that this Aβ-induced increase in burrowing might be associated with a mild anxiety state, which was revealed by increased freezing behavior in the open field, and conclude that Aβ-induced hippocampal dysfunction is reflected in the impairment of ADL and memory, through mechanisms yet to be determined.
The Effects of Valence and Arousal on Associative Working Memory and Long-Term Memory

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Bergmann, Heiko C.; Rijpkema, Mark; Fernández, Guillén; Kessels, Roy P. C.

2012-01-01

Background Emotion can either facilitate or impair memory, depending on what, when and how memory is tested and whether the paradigm at hand is administered as a working memory (WM) or a long-term memory (LTM) task. Whereas emotionally arousing single stimuli are more likely to be remembered, memory for the relationship between two or more component parts (i.e., relational memory) appears to be worse in the presence of emotional stimuli, at least in some relational memory tasks. The current study investigated the effects of both valence (neutral vs. positive vs. negative) and arousal (low vs. high) in an inter-item WM binding and LTM task. Methodology/Principal Findings A five-pair delayed-match-to-sample (WM) task was administered. In each trial, study pairs consisted of one neutral picture and a second picture of which the emotional qualities (valence and arousal levels) were manipulated. These pairs had to be remembered across a delay interval of 10 seconds. This was followed by a probe phase in which five pairs were tested. After completion of this task, an unexpected single item LTM task as well as an LTM task for the pairs was assessed. As expected, emotional arousal impaired WM processing. This was reflected in lower accuracy for pairs consisting of high-arousal pictures compared to pairs with low-arousal pictures. A similar effect was found for the associative LTM task. However, the arousal effect was modulated by affective valence for the WM but not the LTM task; pairs with low-arousal negative pictures were not processed as well in the WM task. No significant differences were found for the single-item LTM task. Conclusions/Significance The present study provides additional evidence that processes during initial perception/encoding and post-encoding processes, the time interval between study and test and the interaction between valence and arousal might modulate the effects of “emotion” on associative memory. PMID:23300724
The Impact of Auditory Working Memory Training on the Fronto-Parietal Working Memory Network

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Julia eSchneiders

2012-06-01

Full Text Available Working memory training has been widely used to investigate working memory processes. We have shown previously that visual working memory benefits only from intra-modal visual but not from across-modal auditory working memory training. In the present functional magnetic resonance imaging study we examined whether auditory working memory processes can also be trained specifically and which training-induced activation changes accompany theses effects. It was investigated whether working memory training with strongly distinct auditory materials transfers exclusively to an auditory (intra-modal working memory task or whether it generalizes to an (across-modal visual working memory task. We used an adaptive n-back training with tonal sequences and a passive control condition. The memory training led to a reliable training gain. Transfer effects were found for the (intra-modal auditory but not for the (across-modal visual 2-back task. Training-induced activation changes in the auditory 2-back task were found in two regions in the right inferior frontal gyrus. These effects confirm our previous findings in the visual modality and extends intra-modal effects to the auditory modality. These results might reflect increased neural efficiency in auditory working memory processes as in the right inferior frontal gyrus is frequently found in maintaining modality-specific auditory information. By this, these effects are analogical to the activation decreases in the right middle frontal gyrus for the visual modality in our previous study. Furthermore, task-unspecific (across-modal activation decreases in the visual and auditory 2-back task were found in the right inferior parietal lobule and the superior portion of the right middle frontal gyrus reflecting less demands on general attentional control processes. These data are in good agreement with across-modal activation decreases within the same brain regions on a visual 2-back task reported previously.

Spermidine Suppresses Age-Associated Memory Impairment by Preventing Adverse Increase of Presynaptic Active Zone Size and Release.

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Varun K Gupta

2016-09-01

Full Text Available Memories are assumed to be formed by sets of synapses changing their structural or functional performance. The efficacy of forming new memories declines with advancing age, but the synaptic changes underlying age-induced memory impairment remain poorly understood. Recently, we found spermidine feeding to specifically suppress age-dependent impairments in forming olfactory memories, providing a mean to search for synaptic changes involved in age-dependent memory impairment. Here, we show that a specific synaptic compartment, the presynaptic active zone (AZ, increases the size of its ultrastructural elaboration and releases significantly more synaptic vesicles with advancing age. These age-induced AZ changes, however, were fully suppressed by spermidine feeding. A genetically enforced enlargement of AZ scaffolds (four gene-copies of BRP impaired memory formation in young animals. Thus, in the Drosophila nervous system, aging AZs seem to steer towards the upper limit of their operational range, limiting synaptic plasticity and contributing to impairment of memory formation. Spermidine feeding suppresses age-dependent memory impairment by counteracting these age-dependent changes directly at the synapse.
Contribution Of Brain Tissue Oxidative Damage In Hypothyroidism-associated Learning and Memory Impairments

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Yousef Baghcheghi

2017-01-01

Full Text Available The brain is a critical target organ for thyroid hormones, and modifications in memory and cognition happen with thyroid dysfunction. The exact mechanisms underlying learning and memory impairments due to hypothyroidism have not been understood yet. Therefore, this review was aimed to compress the results of previous studies which have examined the contribution of brain tissues oxidative damage in hypothyroidism-associated learning and memory impairments.
Inhibiting the Mitochondrial Calcium Uniporter during Development Impairs Memory in Adult Drosophila.

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Drago, Ilaria; Davis, Ronald L

2016-09-06

The uptake of cytoplasmic calcium into mitochondria is critical for a variety of physiological processes, including calcium buffering, metabolism, and cell survival. Here, we demonstrate that inhibiting the mitochondrial calcium uniporter in the Drosophila mushroom body neurons (MBn)-a brain region critical for olfactory memory formation-causes memory impairment without altering the capacity to learn. Inhibiting uniporter activity only during pupation impaired adult memory, whereas the same inhibition during adulthood was without effect. The behavioral impairment was associated with structural defects in MBn, including a decrease in synaptic vesicles and an increased length in the axons of the αβ MBn. Our results reveal an in vivo developmental role for the mitochondrial uniporter complex in establishing the necessary structural and functional neuronal substrates for normal memory formation in the adult organism. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Both a Nicotinic Single Nucleotide Polymorphism (SNP) and a Noradrenergic SNP Modulate Working Memory Performance when Attention is Manipulated

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Greenwood, Pamela M.; Sundararajan, Ramya; Lin, Ming-Kuan; Kumar, Reshma; Fryxell, Karl J.; Parasuraman, Raja

2009-01-01

We investigated the relation between the two systems of visuospatial attention and working memory by examining the effect of normal variation in cholinergic and noradrenergic genes on working memory performance under attentional manipulation. We previously reported that working memory for location was impaired following large location precues, indicating the scale of visuospatial attention has a role in forming the mental representation of the target. In one of the first studies to compare ef...
Comparison of explicit and incidental learning strategies in memory-impaired patients.

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Smith, Christine N; Urgolites, Zhisen J; Hopkins, Ramona O; Squire, Larry R

2014-01-07

Declarative memory for rapidly learned, novel associations is thought to depend on structures in the medial temporal lobe (MTL), whereas associations learned more gradually can sometimes be supported by nondeclarative memory and by structures outside the MTL. A recent study suggested that even rapidly learned associations can be supported by structures outside the MTL when an incidental encoding procedure termed "fast mapping" (FM) is used. We tested six memory-impaired patients with bilateral damage to hippocampus and one patient with large bilateral lesions of the MTL. Participants saw photographs and names of animals, plants, and foods that were previously unfamiliar (e.g., mangosteen). Instead of asking participants to study name-object pairings for a later memory test (as with traditional memory instructions), participants answered questions that allowed them to infer which object corresponded to a particular name. In a second condition, participants learned name-object associations of unfamiliar items by using standard, explicit encoding instructions (e.g., remember the mangosteen). In FM and explicit encoding conditions, patients were impaired (and performed no better than a group that was given the same tests but had not previously studied the material). The same results were obtained in a second experiment that used the same procedures with modifications to allow for more robust learning and more reliable measures of performance. Thus, our results with the FM procedure and memory-impaired patients yielded the same deficits in learning and memory that have been obtained by using other more traditional paradigms.
Memory assessment in patients with temporal lobe epilepsy to predict memory impairment after surgery: A systematic review.

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Parra-Díaz, P; García-Casares, N

2017-04-19

Given that surgical treatment of refractory mesial temporal lobe epilepsy may cause memory impairment, determining which patients are eligible for surgery is essential. However, there is little agreement on which presurgical memory assessment methods are best able to predict memory outcome after surgery and identify those patients with a greater risk of surgery-induced memory decline. We conducted a systematic literature review to determine which presurgical memory assessment methods best predict memory outcome. The literature search of PubMed gathered articles published between January 2005 and December 2015 addressing pre- and postsurgical memory assessment in mesial temporal lobe epilepsy patients by means of neuropsychological testing, functional MRI, and other neuroimaging techniques. We obtained 178 articles, 31 of which were included in our review. Most of the studies used neuropsychological tests and fMRI; these methods are considered to have the greatest predictive ability for memory impairment. Other less frequently used techniques included the Wada test and FDG-PET. Current evidence supports performing a presurgical assessment of memory function using both neuropsychological tests and functional MRI to predict memory outcome after surgery. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.
Propranolol–induced Impairment of Contextual Fear Memory Reconsolidation in Rats: A similar Effect on Weak and Strong Recent and Remote Memories

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Taherian, Fatemeh; Vafaei, Abbas Ali; Vaezi, Gholam Hassan; Eskandarian, Sharaf; Kashef, Adel; Rashidy-Pour, Ali

2014-01-01

Introduction Previous studies have demonstrated that the β-adrenergic receptor antagonist propranolol impairs fear memory reconsolidation in experimental animals. There are experimental parameters such as the age and the strength of memory that can interact with pharmacological manipulations of memory reconsolidation. In this study, we investigated the ability of the age and the strength of memory to influence the disrupting effects of propranolol on fear memory reconsolidation in rats. Methods The rats were trained in a contextual fear conditioning using two (weak training) or five (strong training) footshocks (1mA). Propranolol (10mg/kg) injection was immediately followed retrieval of either a one-day recent (weak or strong) or 36-day remote (weak or strong) contextual fear memories. Results We found that propranolol induced a long-lasting impairment of subsequent expression of recent and remote memories with either weak or strong strength. We also found no memory recovery after a weak reminder shock. Furthermore, no significant differences were found on the amount of memory deficit induced by propranolol among memories with different age and strength. Discussion Our data suggest that the efficacy of propranolol in impairing fear memory reconsolidation is not limited to the age or strength of the memory. PMID:25337385
Working memory impairment in multiple sclerosis relapsing-remitting patients with episodic memory deficits Prejuízo de memória operacional em pacientes com esclerose múltipla recorrente-remitente com déficits de memória episódica

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Simone Freitas Fuso

2010-04-01

Full Text Available Episodic memory is impaired in multiple sclerosis (MS patients, possibly because of deficits in working memory (WM functioning. If so, WM alterations should necessarily be found in patients with episodic memory deficits, but this has not yet been demonstrated. In this study we aimed at determining whether episodic memory deficits in relapsing-remitting MS are found in conjunction with impaired WM. We evaluated 32 MS patients and 32 matched healthy controls. Nineteen of the 32 patients had episodic memory impairment, and as a group only these individuals showed deficits in WM capacity, which may lead to difficulty in encoding, and/or retrieving information from episodic memory.Pacientes com esclerose múltipla (EM apresentam prejuízo de memória episódica possivelmente em decorrência de um déficit no funcionamento da memória operacional (MO. Se assim fosse, alterações de MO seriam necessariamente encontradas em pacientes com déficit de memória episódica, mas isto ainda não foi demonstrado. Neste estudo tivemos como objetivo determinar se déficits de memória episódica em pacientes com EM recorrente-remitente são encontrados em associação com prejuízo de MO. Avaliamos 32 pacientes com EM pareados com 32 voluntários saudáveis. Dezenove dos 32 pacientes apresentaram prejuízo de memória episódica, e como grupo, somente estes indivíduos apresentaram déficit na capacidade de MO, o que deve resultar na dificuldade de codificar, e /ou recuperar informações da memória episódica.
Genetic Disruption of the Core Circadian Clock Impairs Hippocampus-Dependent Memory

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Wardlaw, Sarah M.; Phan, Trongha X.; Saraf, Amit; Chen, Xuanmao; Storm, Daniel R.

2014-01-01

Perturbing the circadian system by electrolytically lesioning the suprachiasmatic nucleus (SCN) or varying the environmental light:dark schedule impairs memory, suggesting that memory depends on the circadian system. We used a genetic approach to evaluate the role of the molecular clock in memory. Bmal1[superscript -/-] mice, which are arrhythmic…
Hemispatial neglect and serial order in verbal working memory.

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Antoine, Sophie; Ranzini, Mariagrazia; van Dijck, Jean-Philippe; Slama, Hichem; Bonato, Mario; Tousch, Ann; Dewulf, Myrtille; Bier, Jean-Christophe; Gevers, Wim

2018-01-09

Working memory refers to our ability to actively maintain and process a limited amount of information during a brief period of time. Often, not only the information itself but also its serial order is crucial for good task performance. It was recently proposed that serial order is grounded in spatial cognition. Here, we compared performance of a group of right hemisphere-damaged patients with hemispatial neglect to healthy controls in verbal working memory tasks. Participants memorized sequences of consonants at span level and had to judge whether a target consonant belonged to the memorized sequence (item task) or whether a pair of consonants were presented in the same order as in the memorized sequence (order task). In line with this idea that serial order is grounded in spatial cognition, we found that neglect patients made significantly more errors in the order task than in the item task compared to healthy controls. Furthermore, this deficit seemed functionally related to neglect severity and was more frequently observed following right posterior brain damage. Interestingly, this specific impairment for serial order in verbal working memory was not lateralized. We advance the hypotheses of a potential contribution to the deficit of serial order in neglect patients of either or both (1) reduced spatial working memory capacity that enables to keep track of the spatial codes that provide memorized items with a positional context, (2) a spatial compression of these codes in the intact representational space. © 2018 The British Psychological Society.
Cerebellar transcranial direct current stimulation modulates verbal working memory.

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Boehringer, Andreas; Macher, Katja; Dukart, Juergen; Villringer, Arno; Pleger, Burkhard

2013-07-01

Neuroimaging studies show cerebellar activations in a wide range of cognitive tasks and patients with cerebellar lesions often present cognitive deficits suggesting a cerebellar role in higher-order cognition. We used cathodal transcranial direct current stimulation (tDCS), known to inhibit neuronal excitability, over the cerebellum to investigate if cathodal tDCS impairs verbal working memory, an important higher-order cognitive faculty. We tested verbal working memory as measured by forward and backward digit spans in 40 healthy young participants before and after applying cathodal tDCS (2 mA, stimulation duration 25 min) to the right cerebellum using a randomized, sham-controlled, double-blind, cross-over design. In addition, we tested the effect of cerebellar tDCS on word reading, finger tapping and a visually cued sensorimotor task. In line with lower digit spans in patients with cerebellar lesions, cerebellar tDCS reduced forward digit spans and blocked the practice dependent increase in backward digit spans. No effects of tDCS on word reading, finger tapping or the visually cued sensorimotor task were found. Our results support the view that the cerebellum contributes to verbal working memory as measured by forward and backward digit spans. Moreover, the induction of reversible "virtual cerebellar lesions" in healthy individuals by means of tDCS may improve our understanding of the mechanistic basis of verbal working memory deficits in patients with cerebellar lesions. Copyright © 2013 Elsevier Inc. All rights reserved.
Evidence for modality-independent order coding in working memory.

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Depoorter, Ann; Vandierendonck, André

2009-03-01

The aim of the present study was to investigate the representation of serial order in working memory, more specifically whether serial order is coded by means of a modality-dependent or a modality-independent order code. This was investigated by means of a series of four experiments based on a dual-task methodology in which one short-term memory task was embedded between the presentation and recall of another short-term memory task. Two aspects were varied in these memory tasks--namely, the modality of the stimulus materials (verbal or visuo-spatial) and the presence of an order component in the task (an order or an item memory task). The results of this study showed impaired primary-task recognition performance when both the primary and the embedded task included an order component, irrespective of the modality of the stimulus materials. If one or both of the tasks did not contain an order component, less interference was found. The results of this study support the existence of a modality-independent order code.
Basolateral amygdala GABA-A receptors mediate stress-induced memory retrieval impairment in rats.

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Sardari, Maryam; Rezayof, Ameneh; Khodagholi, Fariba; Zarrindast, Mohammad-Reza

2014-04-01

The present study was designed to investigate the involvement of GABA-A receptors of the basolateral amygdala (BLA) in the impairing effect of acute stress on memory retrieval. The BLAs of adult male Wistar rats were bilaterally cannulated and memory retrieval was measured in a step-through type passive avoidance apparatus. Acute stress was evoked by placing the animals on an elevated platform for 10, 20 and 30 min. The results indicated that exposure to 20 and 30 min stress, but not 10 min, before memory retrieval testing (pre-test exposure to stress) decreased the step-through latency, indicating stress-induced memory retrieval impairment. Intra-BLA microinjection of a GABA-A receptor agonist, muscimol (0.005-0.02 μg/rat), 5 min before exposure to an ineffective stress (10 min exposure to stress) induced memory retrieval impairment. It is important to note that pre-test intra-BLA microinjection of the same doses of muscimol had no effect on memory retrieval in the rats unexposed to 10 min stress. The blockade of GABA-A receptors of the BLA by injecting an antagonist, bicuculline (0.4-0.5 μg/rat), 5 min before 20 min exposure to stress, prevented stress-induced memory retrieval. Pre-test intra-BLA microinjection of the same doses of bicuculline (0.4-0.5 μg/rat) in rats unexposed to 20 min stress had no effect on memory retrieval. In addition, pre-treatment with bicuculline (0.1-0.4 μg/rat, intra-BLA) reversed muscimol (0.02 μg/rat, intra-BLA)-induced potentiation on the effect of stress in passive avoidance learning. It can be concluded that pre-test exposure to stress can induce memory retrieval impairment and the BLA GABA-A receptors may be involved in stress-induced memory retrieval impairment.
Neural Correlates of Opposing Effects of Emotional Distraction on Working Memory and Episodic Memory: An Event Related fMRI Investigation

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Florin eDolcos

2013-06-01

Full Text Available A fundamental question in the emotional memory literature is why emotion enhances memory in some conditions but disrupts memory in other conditions. For example, separate studies have shown that emotional stimuli tend to be better remembered in long-term episodic memory (EM, whereas emotional distracters tend to impair working memory (WM maintenance. The first goal of this study was to directly compare the neural correlates of EM enhancement (EME and WM impairing (WMI effects, and the second goal was to explore individual differences in these mechanisms. During event-related fMRI, participants maintained faces in WM while being distracted by emotional or neutral pictures presented during the delay period. EM for the distracting pictures was tested after scanning and was used to identify successful encoding activity for the picture distracters. The first goal yielded two findings: (1 Emotional pictures that disrupted face WM but enhanced subsequent EM were associated with increased amygdala and hippocampal activity (ventral system coupled with reduced dorsolateral PFC activity (dorsal system; (2 Trials in which emotion enhanced EM without disrupting WM were associated with increased ventrolateral PFC activity. The ventral-dorsal switch can explain EME and WMI, while the ventrolateral PFC effect suggests a coping mechanism. The second goal yielded two additional findings: (3 Participants who were more susceptible to WMI showed greater amygdala increases and PFC reductions; (4 Amygdala activity increased and dlPFC activity decreased with measures of impulsivity. Taken together, the results clarify the mechanisms linking the enhancing and impairing effects of emotion on memory.
Source Memory for Self and Other in Patients With Mild Cognitive Impairment due to Alzheimer’s Disease

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Deason, Rebecca G.; Budson, Andrew E.; Gutchess, Angela H.

2016-01-01

Objectives. The present study examined the role of enactment in source memory in a cognitively impaired population. As seen in healthy older adults, it was predicted that source memory in people with mild cognitive impairment due to Alzheimer’s disease (MCI-AD) would benefit from the self-reference aspect of enactment. Method. Seventeen participants with MCI-AD and 18 controls worked in small groups to pack a picnic basket and suitcase and were later tested for their source memory for each item. Results. For item memory, self-referencing improved corrected recognition scores for both MCI-AD and control participants. The MCI-AD group did not demonstrate the same benefit as controls in correct source memory for self-related items. However, those with MCI-AD were relatively less likely to misattribute new items to the self and more likely to misattribute new items to others when committing errors, compared with controls. Discussion. The enactment effect and self-referencing did not enhance accurate source memory more than other referencing for patients with MCI-AD. However, people with MCI-AD benefited in item memory and source memory, being less likely to falsely claim new items as their own, indicating some self-reference benefit occurs for people with MCI-AD. PMID:24904049
Cannabis-induced impairment of learning and memory: effect of different nootropic drugs

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Abdel-Salam, Omar M.E.; Salem, Neveen A.; El-Sayed El-Shamarka, Marwa; Al-Said Ahmed, Noha; Seid Hussein, Jihan; El-Khyat, Zakaria A.

2013-01-01

Cannabis sativa preparations are the most commonly used illicit drugs worldwide. The present study aimed to investigate the effect of Cannabis sativa extract in the working memory version of the Morris water maze (MWM; Morris, 1984[43]) test and determine the effect of standard memory enhancing drugs. Cannabis sativa was given at doses of 5, 10 or 20 mg/kg (expressed as Δ9-tetrahydrocannabinol) alone or co-administered with donepezil (1 mg/kg), piracetam (150 mg/ kg), vinpocetine (1.5 mg/kg) or ginkgo biloba (25 mg/kg) once daily subcutaneously (s.c.) for one month. Mice were examined three times weekly for their ability to locate a submerged platform. Mice were euthanized 30 days after starting cannabis injection when biochemical assays were carried out. Malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide, glucose and brain monoamines were determined. Cannabis resulted in a significant increase in the time taken to locate the platform and enhanced the memory impairment produced by scopolamine. This effect of cannabis decreased by memory enhancing drugs with piracetam resulting in the most-shorter latency compared with the cannabis. Biochemically, cannabis altered the oxidative status of the brain with decreased MDA, increased GSH, but decreased nitric oxide and glucose. In cannabis-treated rats, the level of GSH in brain was increased after vinpocetine and donepezil and was markedly elevated after Ginkgo biloba. Piracetam restored the decrease in glucose and nitric oxide by cannabis. Cannabis caused dose-dependent increases of brain serotonin, noradrenaline and dopamine. After cannabis treatment, noradrenaline is restored to its normal value by donepezil, vinpocetine or Ginkgo biloba, but increased by piracetam. The level of dopamine was significantly reduced by piracetam, vinpocetine or Ginkgo biloba. These data indicate that cannabis administration is associated with impaired memory performance which is likely to involve decreased brain glucose
Prefrontal activation may predict working-memory training gain in normal aging and mild cognitive impairment.

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Vermeij, Anouk; Kessels, Roy P C; Heskamp, Linda; Simons, Esther M F; Dautzenberg, Paul L J; Claassen, Jurgen A H R

2017-02-01

Cognitive training has been shown to result in improved behavioral performance in normal aging and mild cognitive impairment (MCI), yet little is known about the neural correlates of cognitive plasticity, or about individual differences in responsiveness to cognitive training. In this study, 21 healthy older adults and 14 patients with MCI received five weeks of adaptive computerized working-memory (WM) training. Before and after training, functional Near-Infrared Spectroscopy (fNIRS) was used to assess the hemodynamic response in left and right prefrontal cortex during performance of a verbal n-back task with varying levels of WM load. After training, healthy older adults demonstrated decreased prefrontal activation at high WM load, which may indicate increased processing efficiency. Although MCI patients showed improved behavioral performance at low WM load after training, no evidence was found for training-related changes in prefrontal activation. Whole-group analyses showed that a relatively strong hemodynamic response at low WM load was related to worse behavioral performance, while a relatively strong hemodynamic response at high WM load was related to higher training gain. Therefore, a 'youth-like' prefrontal activation pattern at older age may be associated with better behavioral outcome and cognitive plasticity.
Episodic memory impairment in systemic lupus erythematosus: involvement of thalamic structures.

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Zimmermann, Nicolle; Corrêa, Diogo Goulart; Netto, Tania Maria; Kubo, Tadeu; Pereira, Denis Batista; Fonseca, Rochele Paz; Gasparetto, Emerson Leandro

2015-02-01

Episodic memory deficits in systemic lupus erythematosus (SLE) have been frequently reported in the literature; however, little is known about the neural correlates of these deficits. We investigated differences in the volumes of different brain structures of SLE patients with and without episodic memory impairments diagnosed by the Rey Auditory Verbal Learning Test (RAVLT). Groups were paired based on age, education, sex, Mini Mental State Examination score, accumulation of disease burden (SLICC), and focused attention dimension score. Patients underwent magnetic resonance imaging (MRI). Cortical volumetric reconstruction and segmentation of the MR images were performed with the FreeSurfer software program. SLE patients with episodic memory deficits presented shorter time of diagnosis than SLE patients without episodic memory deficits. ANOVA revealed that SLE patients with episodic memory deficits had a larger third ventricle volume than SLE patients without episodic memory deficits and controls. Additionally, covariance analysis indicated group effects on the bilateral thalamus and on the third ventricle. Our findings indicate that episodic memory may be impaired in SLE patients with normal hippocampal volume. In addition, the thalamus may undergo volumetric changes associated with episodic memory loss in SLE.
Caffeine attenuates scopolamine-induced memory impairment in humans.

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Riedel, W; Hogervorst, E; Leboux, R; Verhey, F; van Praag, H; Jolles, J

1995-11-01

Caffeine consumption can be beneficial for cognitive functioning. Although caffeine is widely recognized as a mild CNS stimulant drug, the most important consequence of its adenosine antagonism is cholinergic stimulation, which might lead to improvement of higher cognitive functions, particularly memory. In this study, the scopolamine model of amnesia was used to test the cholinergic effects of caffeine, administered as three cups of coffee. Subjects were 16 healthy volunteers who received 250 mg caffeine and 2 mg nicotine separately, in a placebo-controlled double-blind cross-over design. Compared to placebo, nicotine attenuated the scopolamine-induced impairment of storage in short-term memory and attenuated the scopolamine-induced slowing of speed of short-term memory scanning. Nicotine also attenuated the scopolamine-induced slowing of reaction time in a response competition task. Caffeine attenuated the scopolamine-induced impairment of free recall from short- and long-term memory, quality and speed of retrieval from long-term memory in a word learning task, and other cognitive and non-cognitive measures, such as perceptual sensitivity in visual search, reading speed, and rate of finger-tapping. On the basis of these results it was concluded that caffeine possesses cholinergic cognition enhancing properties. Caffeine could be used as a control drug in studies using the scopolamine paradigm and possibly also in other experimental studies of cognitive enhancers, as the effects of a newly developed cognition enhancing drug should at least be superior to the effects of three cups of coffee.
Different types of working memory binding in epilepsy patients with unilateral anterior temporal lobectomy.

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van Geldorp, Bonnie; Bouman, Zita; Hendriks, Marc P H; Kessels, Roy P C

2014-03-01

The medial temporal lobe is an important structure for long-term memory formation, but its role in working memory is less clear. Recent studies have shown hippocampal involvement during working memory tasks requiring binding of information. It is yet unclear whether this is limited to tasks containing spatial features. The present study contrasted three binding conditions and one single-item condition in patients with unilateral anterior temporal lobectomy. A group of 43 patients with temporal lobectomy (23 left; 20 right) and 20 matched controls were examined with a working memory task assessing spatial relational binding (object-location), non-spatial relational binding (object-object), conjunctive binding (object-colour) and working memory for single items. We varied the delay period (3 or 6s), as there is evidence showing that delay length may modulate working memory performance. The results indicate that performance was worse for patients than for controls in both relational binding conditions, whereas patients were unimpaired in conjunctive binding. Single-item memory was found to be marginally impaired, due to a deficit on long-delay trials only. In conclusion, working memory binding deficits are found in patients with unilateral anterior temporal lobectomy. The role of the medial temporal lobe in working memory is not limited to tasks containing spatial features. Rather, it seems to be involved in relational binding, but not in conjunctive binding. The medial temporal lobe gets involved when working memory capacity does not suffice, for example when relations have to be maintained or when the delay period is long. Copyright © 2014 Elsevier Inc. All rights reserved.

The heterogeneity and natural history of mild cognitive impairment of visual memory predominant type.

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Ye, Byoung Seok; Chin, Juhee; Kim, Seong Yoon; Lee, Jung-Sun; Kim, Eun-Joo; Lee, Yunhwan; Hong, Chang Hyung; Choi, Seong Hye; Park, Kyung Won; Ku, Bon D; Moon, So Young; Kim, SangYun; Han, Seol-Hee; Lee, Jae-Hong; Cheong, Hae-Kwan; Park, Sun Ah; Jeong, Jee Hyang; Na, Duk L; Seo, Sang Won

2015-01-01

We evaluate the longitudinal outcomes of amnestic mild cognitive impairment (aMCI) according to the modality of memory impairment involved. We recruited 788 aMCI patients and followed them up. aMCI patients were categorized into three groups according to the modality of memory impairment: Visual-aMCI, only visual memory impaired; Verbal-aMCI, only verbal memory impaired; and Both-aMCI, both visual and verbal memory impaired. Each aMCI group was further categorized according to the presence or absence of recognition failure. Risk of progression to dementia was compared with pooled logistic regression analyses while controlling for age, gender, education, and interval from baseline. Of the sample, 219 (27.8%) aMCI patients progressed to dementia. Compared to the Visual-aMCI group, Verbal-aMCI (OR = 1.98, 95% CI = 1.19-3.28, p = 0.009) and Both-aMCI (OR = 3.05, 95% CI = 1.97-4.71, p Memory recognition failure was associated with increased risk of progression to dementia only in the Visual-aMCI group, but not in the Verbal-aMCI and Both-aMCI groups. The Visual-aMCI without recognition failure group were subcategorized into aMCI with depression, small vessel disease, or accelerated aging, and these subgroups showed a variety of progression rates. Our findings underlined the importance of heterogeneous longitudinal outcomes of aMCI, especially Visual-aMCI, for designing and interpreting future treatment trials in aMCI.
Everyday episodic memory in amnestic mild cognitive impairment: a preliminary investigation

OpenAIRE

LAWLOR, BRIAN; COEN, ROBERT; O'MARA, SHANE MICHAEL

2011-01-01

PUBLISHED Background: Decline in episodic memory is one of the hallmark features of Alzheimer's disease (AD) and is also a defining feature of amnestic Mild Cognitive Impairment (MCI), which is posited as a potential prodrome of AD. While deficits in episodic memory are well documented in MCI, the nature of this impairment remains relatively under-researched, particularly for those domains with direct relevance and meaning for the patient's daily life. In order to fully explore the impa...
Everyday episodic memory in amnestic mild cognitive impairment: a preliminary investigation

OpenAIRE

Irish, Muireann; Lawlor, Brian A; Coen, Robert F; O'Mara, Shane M

2011-01-01

Abstract Background Decline in episodic memory is one of the hallmark features of Alzheimer's disease (AD) and is also a defining feature of amnestic Mild Cognitive Impairment (MCI), which is posited as a potential prodrome of AD. While deficits in episodic memory are well documented in MCI, the nature of this impairment remains relatively under-researched, particularly for those domains with direct relevance and meaning for the patient's daily life. In order to fully explore the impact of di...
Semantic memory impairment in the earliest phases of Alzheimer's disease

DEFF Research Database (Denmark)

Vogel, Asmus; Gade, Anders; Stokholm, Jette

2005-01-01

The presence and the nature of semantic memory dysfunction in Alzheimer's disease (AD) have been widely debated. This study aimed to determine the frequency of impaired semantic test performances in mild AD and to study whether incipient semantic impairments could be identified in predementia AD...
Visual working memory buffers information retrieved from visual long-term memory.

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Fukuda, Keisuke; Woodman, Geoffrey F

2017-05-16

Human memory is thought to consist of long-term storage and short-term storage mechanisms, the latter known as working memory. Although it has long been assumed that information retrieved from long-term memory is represented in working memory, we lack neural evidence for this and need neural measures that allow us to watch this retrieval into working memory unfold with high temporal resolution. Here, we show that human electrophysiology can be used to track information as it is brought back into working memory during retrieval from long-term memory. Specifically, we found that the retrieval of information from long-term memory was limited to just a few simple objects' worth of information at once, and elicited a pattern of neurophysiological activity similar to that observed when people encode new information into working memory. Our findings suggest that working memory is where information is buffered when being retrieved from long-term memory and reconcile current theories of memory retrieval with classic notions about the memory mechanisms involved.
Working Memory Modulation of Frontoparietal Network Connectivity in First-Episode Schizophrenia

DEFF Research Database (Denmark)

Nielsen, Jesper Duemose; Madsen, Kristoffer Hougaard; Wang, Zheng

2017-01-01

Working memory (WM) impairment is regarded as a core aspect of schizophrenia. However, the neural mechanisms behind this cognitive deficit remain unclear. The connectivity of a frontoparietal network is known to be important for subserving WM. Using functional magnetic resonance imaging, the curr......Working memory (WM) impairment is regarded as a core aspect of schizophrenia. However, the neural mechanisms behind this cognitive deficit remain unclear. The connectivity of a frontoparietal network is known to be important for subserving WM. Using functional magnetic resonance imaging......, the current study investigated whether WM-dependent modulation of effective connectivity in this network is affected in a group of first-episode schizophrenia (FES) patients compared with similarly performing healthy participants during a verbal n-back task. Dynamic causal modeling (DCM) of the coupling...... between regions (left inferior frontal gyrus (IFG), left inferior parietal lobe (IPL), and primary visual area) identified in a psychophysiological interaction (PPI) analysis was performed to characterize effective connectivity during the n-back task. The PPI analysis revealed that the connectivity...
Evidence for a Double Dissociation between Spatial-Simultaneous and Spatial-Sequential Working Memory in Visuospatial (Nonverbal) Learning Disabled Children

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Mammarella, Irene C.; Cornoldi, Cesare; Pazzaglia, Francesca; Toso, Cristina; Grimoldi, Mario; Vio, Claudio

2006-01-01

The paper describes the performance of three children with specific visuospatial working memory (VSWM) impairments (Study 1) and three children with visuospatial (nonverbal) learning disabilities (Study 2) assessed with a battery of working memory (WM) tests and with a number of school achievement tasks. Overall, performance on WM tests provides…
Working Memory in Children With Learning Disabilities in Reading Versus Spelling: Searching for Overlapping and Specific Cognitive Factors.

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Brandenburg, Janin; Klesczewski, Julia; Fischbach, Anne; Schuchardt, Kirsten; Büttner, Gerhard; Hasselhorn, Marcus

2015-01-01

In transparent orthographies like German, isolated learning disabilities in either reading or spelling are common and occur as often as a combined reading and spelling disability. However, most issues surrounding the cognitive causes of these isolated or combined literacy difficulties are yet unresolved. Recently, working memory dysfunctions have been demonstrated to be promising in explaining the emergence of literacy difficulties. Thus, we applied a 2 (reading disability: yes vs. no) × 2 (spelling disability: yes vs. no) factorial design to examine distinct and overlapping working memory profiles associated with learning disabilities in reading versus spelling. Working memory was assessed in 204 third graders, and multivariate analyses of variance were conducted for each working memory component. Children with spelling disability suffered from more pronounced phonological loop impairments than those with reading disability. In contrast, domain-general central-executive dysfunctions were solely associated with reading disability, but not with spelling disability. Concerning the visuospatial sketchpad, no impairments were found. In sum, children with reading disability and those with spelling disability seem to be characterized by different working memory profiles. Thus, it is important to take both reading and spelling into account when investigating cognitive factors of literacy difficulties in transparent orthographies. © Hammill Institute on Disabilities 2014.
Emotional arousal impairs association-memory: Roles of amygdala and hippocampus.

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Madan, Christopher R; Fujiwara, Esther; Caplan, Jeremy B; Sommer, Tobias

2017-08-01

Emotional arousal is well-known to enhance memory for individual items or events, whereas it can impair association memory. The neural mechanism of this association memory impairment by emotion is not known: In response to emotionally arousing information, amygdala activity may interfere with hippocampal associative encoding (e.g., via prefrontal cortex). Alternatively, emotional information may be harder to unitize, resulting in reduced availability of extra-hippocampal medial temporal lobe support for emotional than neutral associations. To test these opposing hypotheses, we compared neural processes underlying successful and unsuccessful encoding of emotional and neutral associations. Participants intentionally studied pairs of neutral and negative pictures (Experiments 1-3). We found reduced association-memory for negative pictures in all experiments, accompanied by item-memory increases in Experiment 2. High-resolution fMRI (Experiment 3) indicated that reductions in associative encoding of emotional information are localizable to an area in ventral-lateral amygdala, driven by attentional/salience effects in the central amygdala. Hippocampal activity was similar during both pair types, but a left hippocampal cluster related to successful encoding was observed only for negative pairs. Extra-hippocampal associative memory processes (e.g., unitization) were more effective for neutral than emotional materials. Our findings suggest that reduced emotional association memory is accompanied by increases in activity and functional coupling within the amygdala. This did not disrupt hippocampal association-memory processes, which indeed were critical for successful emotional association memory formation. Copyright © 2017 Elsevier Inc. All rights reserved.
Visual-spatial processing and working-memory load as a function of negative and positive psychotic-like experiences.

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Abu-Akel, A; Reniers, R L E P; Wood, S J

2016-09-01

Patients with schizophrenia show impairments in working-memory and visual-spatial processing, but little is known about the dynamic interplay between the two. To provide insight into this important question, we examined the effect of positive and negative symptom expressions in healthy adults on perceptual processing while concurrently performing a working-memory task that requires the allocations of various degrees of cognitive resources. The effect of positive and negative symptom expressions in healthy adults (N = 91) on perceptual processing was examined in a dual-task paradigm of visual-spatial working memory (VSWM) under three conditions of cognitive load: a baseline condition (with no concurrent working-memory demand), a low VSWM load condition, and a high VSWM load condition. Participants overall performed more efficiently (i.e., faster) with increasing cognitive load. This facilitation in performance was unrelated to symptom expressions. However, participants with high-negative, low-positive symptom expressions were less accurate in the low VSWM condition compared to the baseline and the high VSWM load conditions. Attenuated, subclinical expressions of psychosis affect cognitive performance that is impaired in schizophrenia. The "resource limitations hypothesis" may explain the performance of the participants with high-negative symptom expressions. The dual-task of visual-spatial processing and working memory may be beneficial to assessing the cognitive phenotype of individuals with high risk for schizophrenia spectrum disorders.
Isoflurane-induced spatial memory impairment in mice is prevented by the acetylcholinesterase inhibitor donepezil.

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Diansan Su

Full Text Available Although many studies have shown that isoflurane exposure impairs spatial memory in aged animals, there are no clinical treatments available to prevent this memory deficit. The anticholinergic properties of volatile anesthetics are a biologically plausible cause of cognitive dysfunction in elderly subjects. We hypothesized that pretreatment with the acetylcholinesterase inhibitor donepezil, which has been approved by the Food and Drug Administration (FDA for the treatment of Alzheimer's disease, prevents isoflurane-induced spatial memory impairment in aged mice. In present study, eighteen-month-old mice were administered donepezil (5 mg/kg or an equal volume of saline by oral gavage with a feeding needle for four weeks. Then the mice were exposed to isoflurane (1.2% for six hours. Two weeks later, mice were subjected to the Morris water maze to examine the impairment of spatial memory after exposure to isoflurane. After the behavioral test, the mice were sacrificed, and the protein expression level of acetylcholinesterase (AChE, choline acetylase (ChAT and α7 nicotinic receptor (α7-nAChR were measured in the brain. Each group consisted of 12 mice. We found that isoflurane exposure for six hours impaired the spatial memory of the mice. Compared with the control group, isoflurane exposure dramatically decreased the protein level of ChAT, but not AChE or α7-nAChR. Donepezil prevented isoflurane-induced spatial memory impairments and increased ChAT levels, which were downregulated by isoflurane. In conclusions, pretreatment with the AChE inhibitor donepezil prevented isoflurane-induced spatial memory impairment in aged mice. The mechanism was associated with the upregulation of ChAT, which was decreased by isoflurane.
Persistent non-verbal memory impairment in remitted major depression - caused by encoding deficits?

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Behnken, Andreas; Schöning, Sonja; Gerss, Joachim; Konrad, Carsten; de Jong-Meyer, Renate; Zwanzger, Peter; Arolt, Volker

2010-04-01

While neuropsychological impairments are well described in acute phases of major depressive disorders (MDD), little is known about the neuropsychological profile in remission. There is evidence for episodic memory impairments in both acute depressed and remitted patients with MDD. Learning and memory depend on individuals' ability to organize information during learning. This study investigates non-verbal memory functions in remitted MDD and whether nonverbal memory performance is mediated by organizational strategies whilst learning. 30 well-characterized fully remitted individuals with unipolar MDD and 30 healthy controls matching in age, sex and education were investigated. Non-verbal learning and memory were measured by the Rey-Osterrieth-Complex-Figure-Test (RCFT). The RCFT provides measures of planning, organizational skills, perceptual and non-verbal memory functions. For assessing the mediating effects of organizational strategies, we used the Savage Organizational Score. Compared to healthy controls, participants with remitted MDD showed more deficits in their non-verbal memory function. Moreover, participants with remitted MDD demonstrated difficulties in organizing non-verbal information appropriately during learning. In contrast, no impairments regarding visual-spatial functions in remitted MDD were observed. Except for one patient, all the others were taking psychopharmacological medication. The neuropsychological function was solely investigated in the remitted phase of MDD. Individuals with MDD in remission showed persistent non-verbal memory impairments, modulated by a deficient use of organizational strategies during encoding. Therefore, our results strongly argue for additional therapeutic interventions in order to improve these remaining deficits in cognitive function. Copyright 2009 Elsevier B.V. All rights reserved.
Odor recognition memory is not idepentently impaired in Parkinson's disease

NARCIS (Netherlands)

Boesveldt, S.; Muinck Keizer, de R.J.O.; Wolters, E.C.H.; Berendse, H.W.

2009-01-01

The results of previous studies in small groups of Parkinson's disease (PD) patients are inconclusive with regard to the presence of an odor recognition memory impairment in PD. The aim of the present study was to investigate odor recognition memory in PD in a larger group of patients. Odor
Dieting and food cue-related working memory performance

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Adrian Meule

2016-12-01

Full Text Available Executive functioning (e.g., working memory is tightly intertwined with self-regulation. For example, food cue-elicited craving has been found to impair working memory performance. Furthermore, current dieters have been found to show lower working memory performance than non-dieters. Recent research, however, suggests that it is crucial to consider dieting success in addition to current dieting status or restrained eating in order to reveal cognitive mechanisms that are associated with successful eating-related self-regulation. The current study investigated food cue-related working memory performance as a function of dieting status and dieting success in female students. Participants performed an n-back task with pictures of food and neutral objects. Reaction time in response to food pictures was slower than in response to neutral pictures, whereas omission errors did not differ between picture types. Current food craving was increased after performing the food block, but not after the neutral block. There was an indirect effect of current dieting status on higher food craving after the food block, which was mediated by slower reaction time to food vs. neutral pictures. Furthermore, higher dieting success was associated with fewer omission errors in the food vs. neutral block in current dieters. There were no relationships of restrained eating with current food craving and task performance. Results further highlight the need to differentiate between successful and unsuccessful dieting in addition to current dieting status or restrained eating when examining possible mechanisms of overeating or successful restraint. Although palatable food cues induce food craving regardless of dieting success, they may boost executive functioning in successful dieters, which helps them to overcome these temptations.
Dieting and Food Cue-Related Working Memory Performance.

Science.gov (United States)

Meule, Adrian

2016-01-01

Executive functioning (e.g., working memory) is tightly intertwined with self-regulation. For example, food cue-elicited craving has been found to impair working memory performance. Furthermore, current dieters have been found to show lower working memory performance than non-dieters. Recent research, however, suggests that it is crucial to consider dieting success in addition to current dieting status or restrained eating in order to reveal cognitive mechanisms that are associated with successful eating-related self-regulation. The current study investigated food cue-related working memory performance as a function of dieting status and dieting success in female students. Participants performed an n -back task with pictures of food and neutral objects. Reaction time in response to food pictures was slower than in response to neutral pictures, whereas omission errors did not differ between picture types. Current food craving was increased after performing the food block, but not after the neutral block. There was an indirect effect of current dieting status on higher food craving after the food block, which was mediated by slower reaction time to food vs. neutral pictures. Furthermore, higher dieting success was associated with fewer omission errors in the food vs. neutral block in current dieters. There were no relationships of restrained eating with current food craving and task performance. Results further highlight the need to differentiate between successful and unsuccessful dieting in addition to current dieting status or restrained eating when examining possible mechanisms of overeating or successful restraint. Although palatable food cues induce food craving regardless of dieting success, they may boost executive functioning in successful dieters, which helps them to overcome these temptations.
Assessment of short-term memory in Arabic speaking children with specific language impairment.

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Kaddah, F A; Shoeib, R M; Mahmoud, H E

2010-12-15

Children with Specific Language Impairment (SLI) may have some kind of memory disorder that could increase their linguistic impairment. This study assessed the short-term memory skills in Arabic speaking children with either Expressive Language Impairment (ELI) or Receptive/Expressive Language Impairment (R/ELI) in comparison to controls in order to estimate the nature and extent of any specific deficits in these children that could explain the different prognostic results of language intervention. Eighteen children were included in each group. Receptive, expressive and total language quotients were calculated using the Arabic language test. Assessment of auditory and visual short-term memory was done using the Arabic version of the Illinois Test of Psycholinguistic Abilities. Both groups of SLI performed significantly lower linguistic abilities and poorer auditory and visual short-term memory in comparison to normal children. The R/ELI group presented an inferior performance than the ELI group in all measured parameters. Strong association was found between most tasks of auditory and visual short-term memory and linguistic abilities. The results of this study highlighted a specific degree of deficit of auditory and visual short-term memories in both groups of SLI. These deficits were more prominent in R/ELI group. Moreover, the strong association between the different auditory and visual short-term memories and language abilities in children with SLI must be taken into account when planning an intervention program for these children.
Mental Imagery and Visual Working Memory

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Keogh, Rebecca; Pearson, Joel

2011-01-01

Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory - but not iconic visual memory - can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage. PMID:22195024
Mental imagery and visual working memory.

Directory of Open Access Journals (Sweden)

Rebecca Keogh

Full Text Available Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory--but not iconic visual memory--can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage.
Mental imagery and visual working memory.

Science.gov (United States)

Keogh, Rebecca; Pearson, Joel

2011-01-01

Visual working memory provides an essential link between past and future events. Despite recent efforts, capacity limits, their genesis and the underlying neural structures of visual working memory remain unclear. Here we show that performance in visual working memory--but not iconic visual memory--can be predicted by the strength of mental imagery as assessed with binocular rivalry in a given individual. In addition, for individuals with strong imagery, modulating the background luminance diminished performance on visual working memory and imagery tasks, but not working memory for number strings. This suggests that luminance signals were disrupting sensory-based imagery mechanisms and not a general working memory system. Individuals with poor imagery still performed above chance in the visual working memory task, but their performance was not affected by the background luminance, suggesting a dichotomy in strategies for visual working memory: individuals with strong mental imagery rely on sensory-based imagery to support mnemonic performance, while those with poor imagery rely on different strategies. These findings could help reconcile current controversy regarding the mechanism and location of visual mnemonic storage.
Neurotoxicity induced by alkyl nitrites: Impairment in learning/memory and motor coordination.

Science.gov (United States)

Cha, Hye Jin; Kim, Yun Ji; Jeon, Seo Young; Kim, Young-Hoon; Shin, Jisoon; Yun, Jaesuk; Han, Kyoungmoon; Park, Hye-Kyung; Kim, Hyung Soo

2016-04-21

Although alkyl nitrites are used as recreational drugs, there is only little research data regarding their effects on the central nervous system including their neurotoxicity. This study investigated the neurotoxicity of three representative alkyl nitrites (isobutyl nitrite, isoamyl nitrite, and butyl nitrite), and whether it affected learning/memory function and motor coordination in rodents. Morris water maze test was performed in mice after administrating the mice with varying doses of the substances in two different injection schedules of memory acquisition and memory retention. A rota-rod test was then performed in rats. All tested alkyl nitrites lowered the rodents' capacity for learning and memory, as assessed by both the acquisition and retention tests. The results of the rota-rod test showed that isobutyl nitrite in particular impaired motor coordination in chronically treated rats. The mice chronically injected with isoamyl nitrite also showed impaired function, while butyl nitrite had no significant effect. The results of the water maze test suggest that alkyl nitrites may impair learning and memory. Additionally, isoamyl nitrite affected the rodents' motor coordination ability. Collectively, our findings suggest that alkyl nitrites may induce neurotoxicity, especially on the aspect of learning and memory function. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A process-model based approach to prospective memory impairment in Parkinson's disease.

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Kliegel, Matthias; Altgassen, Mareike; Hering, Alexandra; Rose, Nathan S

2011-07-01

The present review discusses the current state of research on the clinical neuropsychology of prospective memory in Parkinson's disease. To do so the paper is divided in two sections. In the first section, we briefly outline key features of the (partly implicit) rationale underlying the available literature on the clinical neuropsychology of prospective memory. Here, we present a conceptual model that guides our approach to the clinical neuropsychology of prospective memory in general and to the effects of Parkinson's disease on prospective memory in particular. In the second section, we use this model to guide our review of the available literature and suggest some open issues and future directions motivated by previous findings and the proposed conceptual model. The review suggests that certain phases of the prospective memory process (intention formation und initiation) are particularly impaired by Parkinson's disease. In addition, it is argued that prospective memory may be preserved when tasks involve specific features (e.g., focal cues) that reduce the need for strategic monitoring processes. In terms of suggestions for future directions, it is noted that intervention studies are needed which target the specific phases of the prospective memory process that are impaired in Parkinson's disease, such as planning interventions. Moreover, it is proposed that prospective memory deficits in Parkinson's disease should be explored in the context of a general impairment in the ability to form an intention and plan or coordinate an appropriate series of actions. Copyright © 2011 Elsevier Ltd. All rights reserved.
Reward acts on the pFC to enhance distractor resistance of working memory representations.

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Fallon, Sean James; Cools, Roshan

2014-12-01

Working memory and reward processing are often thought to be separate, unrelated processes. However, most daily activities involve integrating these two types of information, and the two processes rarely, if ever, occur in isolation. Here, we show that working memory and reward interact in a task-dependent manner and that this task-dependent interaction involves modulation of the pFC by the ventral striatum. Specifically, BOLD signal during gains relative to losses in the ventral striatum and pFC was associated not only with enhanced distractor resistance but also with impairment in the ability to update working memory representations. Furthermore, the effect of reward on working memory was accompanied by differential coupling between the ventral striatum and ignore-related regions in the pFC. Together, these data demonstrate that reward-related signals modulate the balance between cognitive stability and cognitive flexibility by altering functional coupling between the ventral striatum and the pFC.
Reduced prefrontal efficiency for visuospatial working memory in attention-deficit/hyperactivity disorder.

Science.gov (United States)

Bédard, Anne-Claude V; Newcorn, Jeffrey H; Clerkin, Suzanne M; Krone, Beth; Fan, Jin; Halperin, Jeffrey M; Schulz, Kurt P

2014-09-01

Visuospatial working memory impairments have been implicated in the pathophysiology of attention-deficit/hyperactivity disorder (ADHD). However, most ADHD research has focused on the neural correlates of nonspatial mnemonic processes. This study examined brain activation and functional connectivity for visuospatial working memory in youth with and without ADHD. Twenty-four youth with ADHD and 21 age- and sex-matched healthy controls were scanned with functional magnetic resonance imaging while performing an N-back test of working memory for spatial position. Block-design analyses contrasted activation and functional connectivity separately for high (2-back) and low (1-back) working memory load conditions versus the control condition (0-back). The effect of working memory load was modeled with linear contrasts. The 2 groups performed comparably on the task and demonstrated similar patterns of frontoparietal activation, with no differences in linear gains in activation as working memory load increased. However, youth with ADHD showed greater activation in the left dorsolateral prefrontal cortex (DLPFC) and left posterior cingulate cortex (PCC), greater functional connectivity between the left DLPFC and left intraparietal sulcus, and reduced left DLPFC connectivity with left midcingulate cortex and PCC for the high load contrast compared to controls (p 100 voxels). Reanalysis using a more conservative statistical approach (p 100 voxels) yielded group differences in PCC activation and DLPFC-midcingulate connectivity. Youth with ADHD show decreased efficiency of DLPFC for high-load visuospatial working memory and greater reliance on posterior spatial attention circuits to store and update spatial position than healthy control youth. Findings should be replicated in larger samples. Copyright © 2014 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.
Coaching positively influences the effects of working memory training on visual working memory as well as mathematical ability.

Science.gov (United States)

Nelwan, Michel; Vissers, Constance; Kroesbergen, Evelyn H

2018-05-01

The goal of the present study was to test whether the amount of coaching influenced the results of working memory training on both visual and verbal working memory. Additionally, the effects of the working memory training on the amount of progress after specific training in mathematics were evaluated. In this study, 23 children between 9 and 12 years of age with both attentional and mathematical difficulties participated in a working memory training program with a high amount of coaching, while another 25 children received no working memory training. Results of these groups were compared to 21 children who completed the training with a lower amount of coaching. The quality of working memory, as well as mathematic skills, were measured three times using untrained transfer tasks. Bayesian statistics were used to test informative hypotheses. After receiving working memory training, the highly coached group performed better than the group that received less coaching on visual working memory and mathematics, but not on verbal working memory. The highly coached group retained their advantage in mathematics, even though the effect on visual working memory decreased. However, no added effect of working memory training was found on the learning curve during mathematical training. Moreover, the less-coached group was outperformed by the group that did not receive working memory training, both in visual working memory and mathematics. These results suggest that motivation and proper coaching might be crucial for ensuring compliance and effects of working memory training, and that far transfer might be possible. Copyright © 2018 Elsevier Ltd. All rights reserved.
Adenosine A(2A) receptors are necessary and sufficient to trigger memory impairment in adult mice.

Science.gov (United States)

Pagnussat, N; Almeida, A S; Marques, D M; Nunes, F; Chenet, G C; Botton, P H S; Mioranzza, S; Loss, C M; Cunha, R A; Porciúncula, L O

2015-08-01

Caffeine (a non-selective adenosine receptor antagonist) prevents memory deficits in aging and Alzheimer's disease, an effect mimicked by adenosine A2 A receptor, but not A1 receptor, antagonists. Hence, we investigated the effects of adenosine receptor agonists and antagonists on memory performance and scopolamine-induced memory impairment in mice. We determined whether A2 A receptors are necessary for the emergence of memory impairments induced by scopolamine and whether A2 A receptor activation triggers memory deficits in naïve mice, using three tests to assess short-term memory, namely the object recognition task, inhibitory avoidance and modified Y-maze. Scopolamine (1.0 mg·kg(-1) , i.p.) impaired short-term memory performance in all three tests and this scopolamine-induced amnesia was prevented by the A2 A receptor antagonist (SCH 58261, 0.1-1.0 mg·kg(-1) , i.p.) and by the A1 receptor antagonist (DPCPX, 0.2-5.0 mg·kg(-1) , i.p.), except in the modified Y-maze where only SCH58261 was effective. Both antagonists were devoid of effects on memory or locomotion in naïve rats. Notably, the activation of A2 A receptors with CGS 21680 (0.1-0.5 mg·kg(-1) , i.p.) before the training session was sufficient to trigger memory impairment in the three tests in naïve mice, and this effect was prevented by SCH 58261 (1.0 mg·kg(-1) , i.p.). Furthermore, i.c.v. administration of CGS 21680 (50 nmol) also impaired recognition memory in the object recognition task. These results show that A2 A receptors are necessary and sufficient to trigger memory impairment and further suggest that A1 receptors might also be selectively engaged to control the cholinergic-driven memory impairment. © 2015 The British Pharmacological Society.
Memory deficits for facial identity in patients with amnestic mild cognitive impairment (MCI).

Science.gov (United States)

Savaskan, Egemen; Summermatter, Daniel; Schroeder, Clemens; Schächinger, Hartmut

2018-01-01

Faces are among the most relevant social stimuli revealing an encounter's identity and actual emotional state. Deficits in facial recognition may be an early sign of cognitive decline leading to social deficits. The main objective of the present study is to investigate if individuals with amnestic mild cognitive impairment show recognition deficits in facial identity. Thirty-seven individuals with amnestic mild cognitive impairment, multiple-domain (15 female; age: 75±8 yrs.) and forty-one healthy volunteers (24 female; age 71±6 yrs.) participated. All participants completed a human portrait memory test presenting unfamiliar faces with happy and angry emotional expressions. Five and thirty minutes later, old and new neutral faces were presented, and discrimination sensitivity (d') and response bias (C) were assessed as signal detection parameters of cued facial identity recognition. Memory performance was lower in amnestic mild cognitive impairment as compared to control subjects, mainly because of an altered response bias towards an increased false alarm rate (favoring false OLD ascription of NEW items). In both groups, memory performance declined between the early and later testing session, and was always better for acquired happy than angry faces. Facial identity memory is impaired in patients with amnestic mild cognitive impairment. Liberalization of the response bias may reflect a socially motivated compensatory mechanism maintaining an almost identical recognition hit rate of OLD faces in individuals with amnestic mild cognitive impairment.
Working Memory Systems in the Rat.

Science.gov (United States)

Bratch, Alexander; Kann, Spencer; Cain, Joshua A; Wu, Jie-En; Rivera-Reyes, Nilda; Dalecki, Stefan; Arman, Diana; Dunn, Austin; Cooper, Shiloh; Corbin, Hannah E; Doyle, Amanda R; Pizzo, Matthew J; Smith, Alexandra E; Crystal, Jonathon D

2016-02-08

A fundamental feature of memory in humans is the ability to simultaneously work with multiple types of information using independent memory systems. Working memory is conceptualized as two independent memory systems under executive control [1, 2]. Although there is a long history of using the term "working memory" to describe short-term memory in animals, it is not known whether multiple, independent memory systems exist in nonhumans. Here, we used two established short-term memory approaches to test the hypothesis that spatial and olfactory memory operate as independent working memory resources in the rat. In the olfactory memory task, rats chose a novel odor from a gradually incrementing set of old odors [3]. In the spatial memory task, rats searched for a depleting food source at multiple locations [4]. We presented rats with information to hold in memory in one domain (e.g., olfactory) while adding a memory load in the other domain (e.g., spatial). Control conditions equated the retention interval delay without adding a second memory load. In a further experiment, we used proactive interference [5-7] in the spatial domain to compromise spatial memory and evaluated the impact of adding an olfactory memory load. Olfactory and spatial memory are resistant to interference from the addition of a memory load in the other domain. Our data suggest that olfactory and spatial memory draw on independent working memory systems in the rat. Copyright © 2016 Elsevier Ltd. All rights reserved.
A stroke patient with impairment of auditory sensory (echoic) memory.

Science.gov (United States)

Kojima, T; Karino, S; Yumoto, M; Funayama, M

2014-04-01

A 42-year-old man suffered damage to the left supra-sylvian areas due to a stroke and presented with verbal short-term memory (STM) deficits. He occasionally could not recall even a single syllable that he had heard one second before. A study of mismatch negativity using magnetoencephalography suggested that the duration of auditory sensory (echoic) memory traces was reduced on the affected side of the brain. His maximum digit span was four with auditory presentation (equivalent to the 1st percentile for normal subjects), whereas it was up to six with visual presentation (almost within the normal range). He simply showed partial recall in the digit span task, and there was no self correction or incorrect reproduction. From these findings, reduced echoic memory was thought to have affected his verbal short-term retention. Thus, the impairment of verbal short-term memory observed in this patient was "pure auditory" unlike previously reported patients with deficits of the phonological short-term store (STS), which is the next higher-order memory system. We report this case to present physiological and behavioral data suggesting impaired short-term storage of verbal information, and to demonstrate the influence of deterioration of echoic memory on verbal STM.
Theory of mind and verbal working memory deficits in parents of autistic children.

Science.gov (United States)

Gokcen, Sezen; Bora, Emre; Erermis, Serpil; Kesikci, Hande; Aydin, Cahide

2009-03-31

The objective of this study was to investigate the potential values of executive function and social cognition deficits as endophenotypes of autism. While theory of mind (ToM) is generally accepted as a unitary concept, some have suggested that ToM may be separated into two components (mental state reasoning and decoding). In this study, both aspects of ToM and verbal working memory abilities were investigated with relatively demanding tasks. The authors used a neurocognitive battery to compare the executive function and social cognition skills of 76 parents of autistic probands with 41 parents of healthy children. Both groups were matched for IQ, age and gender. Index parents had verbal working memory deficits. They had also low performance on a mental state reasoning task. Index parents had difficulties in reasoning about others' emotions. In contrast to findings in the control group, low performance of mental state reasoning ability was not associated with working memory deficit in index parents. Social cognition and working memory impairments may represent potential endophenotypes, related to an underlying vulnerability for autistic spectrum disorders.
Can PC-based training boost working memory in ADHD preadolescents on medication? : a clinical intervention study

OpenAIRE

Hovik, Kjell Tore

2010-01-01

Children with ADHD suffer from impairments in working memory, and recent studies have documented significant gains in working memory (WM) in children diagnosed with ADHD after participating in a PC-based WM training program. Earlier studies have focused on unmedicated children, while a majority of Norwegian children diagnosed with ADHD take ADHD medication for the disorder. The main question addressed in this study is whether ADHD children on medication would also show significant improvement...
Subthalamic nucleus deep brain stimulation affects distractor interference in auditory working memory.

Science.gov (United States)

Camalier, Corrie R; Wang, Alice Y; McIntosh, Lindsey G; Park, Sohee; Neimat, Joseph S

2017-03-01

Computational and theoretical accounts hypothesize the basal ganglia play a supramodal "gating" role in the maintenance of working memory representations, especially in preservation from distractor interference. There are currently two major limitations to this account. The first is that supporting experiments have focused exclusively on the visuospatial domain, leaving questions as to whether such "gating" is domain-specific. The second is that current evidence relies on correlational measures, as it is extremely difficult to causally and reversibly manipulate subcortical structures in humans. To address these shortcomings, we examined non-spatial, auditory working memory performance during reversible modulation of the basal ganglia, an approach afforded by deep brain stimulation of the subthalamic nucleus. We found that subthalamic nucleus stimulation impaired auditory working memory performance, specifically in the group tested in the presence of distractors, even though the distractors were predictable and completely irrelevant to the encoding of the task stimuli. This study provides key causal evidence that the basal ganglia act as a supramodal filter in working memory processes, further adding to our growing understanding of their role in cognition. Copyright © 2017 Elsevier Ltd. All rights reserved.
The effects of experimental pain and induced optimism on working memory task performance.

Science.gov (United States)

Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L

2016-07-01

Pain can interrupt and deteriorate executive task performance. We have previously shown that experimentally induced optimism can diminish the deteriorating effect of cold pressor pain on a subsequent working memory task (i.e., operation span task). In two successive experiments we sought further evidence for the protective role of optimism on pain-induced working memory impairments. We used another working memory task (i.e., 2-back task) that was performed either after or during pain induction. Study 1 employed a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain)×2 (pre-score vs. post-score) mixed factorial design. In half of the participants optimism was induced by the Best Possible Self (BPS) manipulation, which required them to write and visualize about a life in the future where everything turned out for the best. In the control condition, participants wrote and visualized a typical day in their life (TD). Next, participants completed either the cold pressor task (CPT) or a warm water control task (WWCT). Before (baseline) and after the CPT or WWCT participants working memory performance was measured with the 2-back task. The 2-back task measures the ability to monitor and update working memory representation by asking participants to indicate whether the current stimulus corresponds to the stimulus that was presented 2 stimuli ago. Study 2 had a 2 (optimism vs. no-optimism)×2 (pain vs. no-pain) mixed factorial design. After receiving the BPS or control manipulation, participants completed the 2-back task twice: once with painful heat stimulation, and once without any stimulation (counter-balanced order). Continuous heat stimulation was used with temperatures oscillating around 1°C above and 1°C below the individual pain threshold. In study 1, the results did not show an effect of cold pressor pain on subsequent 2-back task performance. Results of study 2 indicated that heat pain impaired concurrent 2-back task performance. However, no evidence was found
Impairments of learning and memory in the rats after brain irradiation

Energy Technology Data Exchange (ETDEWEB)

Takai, Nobuhiko [National Inst. of Radiological Sciences, Chiba (Japan)

2002-06-01

Clinical trials of hadrontherapy have been carried out world wide at several facilities including National Institute of Radiological Sciences (NIRS). Cerebral dysfunction is one of the major concerns associated with radiotherapy of brain tumors. However, little is known about the neurochemical basis of brain dysfunction induced by proton irradiation. We investigated and reported here the early consequences of brain damages caused by proton beam. The animals that had memorized the location of the standard position were locally irradiated to brain with either 70 MeV protons or 290 MeV carbon ions. At 24 hr after irradiation, impairment of the long-term memory was not observed in the irradiated rats compared to control. Irradiated animals, however, required substantially longer time finding out the standard position than control rats when the standard platform displaced to a position different from memorized position. This follows that a single doses of 30 Gy, either protons or carbon ions, impairs the working memory of animals. Function of muscarinic acetylcholine receptors was analyzed by an in vivo binding assay using radioligand quinuclidinyl benzilate (QNB). Irradiated rats were intravenously injected with 5.5 MBq of {sup 3}H-QNB 24 hr after the irradiation, and decapitated 60 min after tracer injection. The autoradiographic studies showed an transitional increase of {sup 3}H-QNB in vivo binding in the early phase after proton irradiation, even though no change in in-vitro {sup 3}H-QNB binding was see in brain autoradiograms of irradiated rats. The cerebral blood flow and the histrogical features of brain were also changed at 3 months post-irradiation. These results indicate that the memory impairment caused by radiation is closely related to the early change of acetylcholine receptor in vivo. (author)
Impairments of learning and memory in the rats after brain irradiation

International Nuclear Information System (INIS)

Takai, Nobuhiko

2002-01-01

Clinical trials of hadrontherapy have been carried out world wide at several facilities including National Institute of Radiological Sciences (NIRS). Cerebral dysfunction is one of the major concerns associated with radiotherapy of brain tumors. However, little is known about the neurochemical basis of brain dysfunction induced by proton irradiation. We investigated and reported here the early consequences of brain damages caused by proton beam. The animals that had memorized the location of the standard position were locally irradiated to brain with either 70 MeV protons or 290 MeV carbon ions. At 24 hr after irradiation, impairment of the long-term memory was not observed in the irradiated rats compared to control. Irradiated animals, however, required substantially longer time finding out the standard position than control rats when the standard platform displaced to a position different from memorized position. This follows that a single doses of 30 Gy, either protons or carbon ions, impairs the working memory of animals. Function of muscarinic acetylcholine receptors was analyzed by an in vivo binding assay using radioligand quinuclidinyl benzilate (QNB). Irradiated rats were intravenously injected with 5.5 MBq of 3 H-QNB 24 hr after the irradiation, and decapitated 60 min after tracer injection. The autoradiographic studies showed an transitional increase of 3 H-QNB in vivo binding in the early phase after proton irradiation, even though no change in in-vitro 3 H-QNB binding was see in brain autoradiograms of irradiated rats. The cerebral blood flow and the histrogical features of brain were also changed at 3 months post-irradiation. These results indicate that the memory impairment caused by radiation is closely related to the early change of acetylcholine receptor in vivo. (author)
Verbal learning and memory impairments in posttraumatic stress disorder: the role of encoding strategies.

Science.gov (United States)

Johnsen, Grethe E; Asbjørnsen, Arve E

2009-01-30

The present study examined mechanisms underlying verbal memory impairments in patients with posttraumatic stress disorder (PTSD). Earlier studies have reported that the verbal learning and memory alterations in PTSD are related to impaired encoding, but the use of encoding and organizational strategies in patients with PTSD has not been fully explored. This study examined organizational strategies in 21 refugees/immigrants exposed to war and political violence who fulfilled DSM-IV criteria for chronic PTSD compared with a control sample of 21 refugees/immigrants with similar exposure, but without PTSD. The California Verbal Learning Test was administered to examine differences in organizational strategies and memory. The semantic clustering score was slightly reduced in both groups, but the serial cluster score was significantly impaired in the PTSD group and they also reported more items from the recency region of the list. In addition, intrusive errors were significantly increased in the PTSD group. The data support an assumption of changed memory strategies in patients with PTSD associated with a specific impairment in executive control. However, memory impairment and the use of ineffective learning strategies may not be related to PTSD symptomatology only, but also to self-reported symptoms of depression and general distress.
Hilar Interneuron Vulnerability Distinguishes Aged Rats With Memory Impairment

Science.gov (United States)

Spiegel, Amy M.; Koh, Ming Teng; Vogt, Nicholas M.; Rapp, Peter R.; Gallagher, Michela

2016-01-01

Hippocampal interneuron populations are reportedly vulnerable to normal aging. The relationship between interneuron network integrity and age-related memory impairment, however, has not been tested directly. That question was addressed in the present study using a well-characterized model in which outbred, aged, male Long-Evans rats exhibit a spectrum of individual differences in hippocampal-dependent memory. Selected interneuron populations in the hippocampus were visualized for stereological quantification with a panel of immunocytochemical markers, including glutamic acid decarboxylase-67 (GAD67), somatostatin, and neuropeptide Y. The overall pattern of results was that, although the numbers of GAD67- and somatostatin-positive interneurons declined with age across multiple fields of the hippocampus, alterations specifically related to the cognitive outcome of aging were observed exclusively in the hilus of the dentate gyrus. Because the total number of NeuN-immunoreactive hilar neurons was unaffected, the decline observed with other markers likely reflects a loss of target protein rather than neuron death. In support of that interpretation, treatment with the atypical antiepileptic levetiracetam at a low dose shown previously to improve behavioral performance fully restored hilar SOM expression in aged, memory-impaired rats. Age-related decreases in GAD67- and somatostatin-immunoreactive neuron number beyond the hilus were regionally selective and spared the CA1 field of the hippocampus entirely. Together these findings confirm the vulnerability of hippocampal interneurons to normal aging and highlight that the integrity of a specific subpopulation in the hilus is coupled with age-related memory impairment. PMID:23749483
Is the Link from Working Memory to Analogy Causal? No Analogy Improvements following Working Memory Training Gains

OpenAIRE

Richey, J. Elizabeth; Phillips, Jeffrey S.; Schunn, Christian D.; Schneider, Walter

2014-01-01

Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data [1], but less work has tested this relationship through experimental manipulation [2]. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working mem...
Severity of explicit memory impairment due to Alzheimer's disease improves effectiveness of implicit learning.

Science.gov (United States)

Klimkowicz-Mrowiec, Aleksandra; Slowik, Agnieszka; Krzywoszanski, Lukasz; Herzog-Krzywoszanska, Radosława; Szczudlik, Andrzej

2008-04-01

Consistent evidence from human and experimental animals studies indicates that memory is organized into two relatively independent systems with different functions and brain mechanisms. The explicit memory system, dependent on the hippocampus and adjacent medial temporal lobe structures, refers to conscious knowledge acquisition and intentional recollection of previous experiences. The implicit memory system, dependent on the striatum, refers to learning of complex information without awareness or intention. The functioning of implicit memory can be observed in progressive, gradual improvement across many trials in performance on implicit learning tasks. The influence of explicit memory on implicit memory has not been precisely identified yet. According to data from some studies, explicit memory seems to exhibit no influence on implicit memory,whereas the other studies indicate that explicit memory may inhibit or facilitate implicit memory. The analysis of performance on implicit learning tasks in patients with different severity of explicit memory impairment due to Alzheimer's disease allows one to identify the potential influence of the explicit memory system on the implicit memory system. 51 patients with explicit memory impairment due to Alzheimer's disease (AD) and 36 healthy controls were tested. Explicit memory was examined by means of a battery of neuropsychological tests. Implicit habit learning was examined on probabilistic classification task (weather prediction task). Patients with moderate explicit memory impairment performed the implicit task significantly better than those with mild AD and controls. Results of our study support the hypothesis of competition between the implicit and explicit memory systems in humans.
Using memories to understand others: the role of episodic memory in theory of mind impairment in Alzheimer disease.

Science.gov (United States)

Moreau, Noémie; Viallet, François; Champagne-Lavau, Maud

2013-09-01

Theory of mind (TOM) refers to the ability to infer one's own and other's mental states. Growing evidence highlighted the presence of impairment on the most complex TOM tasks in Alzheimer disease (AD). However, how TOM deficit is related to other cognitive dysfunctions and more specifically to episodic memory impairment - the prominent feature of this disease - is still under debate. Recent neuroanatomical findings have shown that remembering past events and inferring others' states of mind share the same cerebral network suggesting the two abilities share a common process .This paper proposes to review emergent evidence of TOM impairment in AD patients and to discuss the evidence of a relationship between TOM and episodic memory. We will discuss about AD patients' deficit in TOM being possibly related to their difficulties in recollecting memories of past social interactions. Copyright © 2013 Elsevier B.V. All rights reserved.
Does working memory training lead to generalized improvements in children with low working memory? A randomized controlled trial

OpenAIRE

Dunning, Darren L; Holmes, Joni; Gathercole, Susan E

2013-01-01

Children with low working memory typically make poor educational progress, and it has been speculated that difficulties in meeting the heavy working memory demands of the classroom may be a contributory factor. Intensive working memory training has been shown to boost performance on untrained memory tasks in a variety of populations. This first randomized controlled trial with low working memory children investigated whether the benefits of training extend beyond standard working memory tasks...

Prospective memory, working memory, retrospective memory and self-rated memory performance in persons with intellectual disability

OpenAIRE

Levén, Anna; Lyxell, Björn; Andersson, Jan; Danielsson, Henrik; Rönnberg, Jerker

2008-01-01

The purpose of the present study was to examine the relationship between prospective memory, working memory, retrospective memory and self-rated memory capacity in adults with and without intellectual disability. Prospective memory was investigated by means of a picture-based task. Working memory was measured as performance on span tasks. Retrospective memory was scored as recall of subject performed tasks. Self-ratings of memory performance were based on the prospective and retrospective mem...
Genetic disruption of the core circadian clock impairs hippocampus-dependent memory

OpenAIRE

2014-01-01

Perturbing the circadian system by electrolytically lesioning the suprachiasmatic nucleus (SCN) or varying the environmental light:dark schedule impairs memory, suggesting that memory depends on the circadian system. We used a genetic approach to evaluate the role of the molecular clock in memory. Bmal1−/− mice, which are arrhythmic under constant conditions, were examined for hippocampus-dependent memory, LTP at the Schaffer-collateral synapse, and signal transduction activity in the hippoca...
Differences between Presentation Methods in Working Memory Procedures: A Matter of Working Memory Consolidation

Science.gov (United States)

Ricker, Timothy J.; Cowan, Nelson

2014-01-01

Understanding forgetting from working memory, the memory used in ongoing cognitive processing, is critical to understanding human cognition. In the past decade, a number of conflicting findings have been reported regarding the role of time in forgetting from working memory. This has led to a debate concerning whether longer retention intervals…
Hippocampal Volume Reduction in Humans Predicts Impaired Allocentric Spatial Memory in Virtual-Reality Navigation.

Science.gov (United States)

Guderian, Sebastian; Dzieciol, Anna M; Gadian, David G; Jentschke, Sebastian; Doeller, Christian F; Burgess, Neil; Mishkin, Mortimer; Vargha-Khadem, Faraneh

2015-10-21

The extent to which navigational spatial memory depends on hippocampal integrity in humans is not well documented. We investigated allocentric spatial recall using a virtual environment in a group of patients with severe hippocampal damage (SHD), a group of patients with "moderate" hippocampal damage (MHD), and a normal control group. Through four learning blocks with feedback, participants learned the target locations of four different objects in a circular arena. Distal cues were present throughout the experiment to provide orientation. A circular boundary as well as an intra-arena landmark provided spatial reference frames. During a subsequent test phase, recall of all four objects was tested with only the boundary or the landmark being present. Patients with SHD were impaired in both phases of this task. Across groups, performance on both types of spatial recall was highly correlated with memory quotient (MQ), but not with intelligence quotient (IQ), age, or sex. However, both measures of spatial recall separated experimental groups beyond what would be expected based on MQ, a widely used measure of general memory function. Boundary-based and landmark-based spatial recall were both strongly related to bilateral hippocampal volumes, but not to volumes of the thalamus, putamen, pallidum, nucleus accumbens, or caudate nucleus. The results show that boundary-based and landmark-based allocentric spatial recall are similarly impaired in patients with SHD, that both types of recall are impaired beyond that predicted by MQ, and that recall deficits are best explained by a reduction in bilateral hippocampal volumes. In humans, bilateral hippocampal atrophy can lead to profound impairments in episodic memory. Across species, perhaps the most well-established contribution of the hippocampus to memory is not to episodic memory generally but to allocentric spatial memory. However, the extent to which navigational spatial memory depends on hippocampal integrity in humans is
Viral-mediated Zif268 expression in the prefrontal cortex protects against gonadectomy-induced working memory, long-term memory, and social interaction deficits in male rats.

Science.gov (United States)

Dossat, Amanda M; Jourdi, Hussam; Wright, Katherine N; Strong, Caroline E; Sarkar, Ambalika; Kabbaj, Mohamed

2017-01-06

In humans, some males experience reductions in testosterone levels, as a natural consequence of aging or in the clinical condition termed hypogonadism, which are associated with impaired cognitive performance and mood disorder(s). Some of these behavioral deficits can be reversed by testosterone treatment. Our previous work in rats reported that sex differences in the expression of the transcription factor Zif268, a downstream target of testosterone, within the medial prefrontal cortex (mPFC) mediates sex differences in social interaction. In the present study, we aimed to examine the effects of gonadectomy (GNX) in male rats on mPFC Zif268 expression, mood and cognitive behaviors. We also examined whether reinstitution of Zif268 in GNX rats will correct some of the behavioral deficits observed following GNX. Our results show that GNX induced a downregulation of Zif268 protein in the mPFC, which was concomitant with impaired memory in the y-maze and spontaneous object recognition test, reduced social interaction time, and depression-like behaviors in the forced swim test. Reinstitution of mPFC Zif268, using a novel adeno-associated-viral (AAV) construct, abrogated GNX-induced working memory and long-term memory impairments, and reductions in social interaction time, but not GNX-induced depression-like behaviors. These findings suggest that mPFC Zif268 exerts beneficial effects on memory and social interaction, and could be a potential target for novel treatments for behavioral impairments observed in hypogonadal and aged men with declining levels of gonadal hormones. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.
Effects of hypoglycaemia on working memory and regional cerebral blood flow in type 1 diabetes: a randomised, crossover trial

DEFF Research Database (Denmark)

Gejl, Michael; Gjedde, Albert; Brock, Birgitte

2018-01-01

(PET) per session. RESULTS: Working memory was impaired during hypoglycaemia as indicated by a statistically significantly lower mDSST score (estimated treatment difference [ETD] -0.63 [95% CI -1.13, -0.14], p = 0.014) and a statistically significantly longer response time (ETD 2.86 s [7%] [95% CI 0.......67, 5.05], p = 0.013) compared with euglycaemia. During hypoglycaemia, mDSST task performance was associated with increased activity in the frontal lobe regions, superior parietal lobe and thalamus, and decreased activity in the temporal lobe regions (p Working memory activation (mDSST - c......DSST) statistically significantly increased blood flow in the striatum during hypoglycaemia (ETD 0.0374% [95% CI 0.0157, 0.0590], p = 0.002). CONCLUSIONS/INTERPRETATION: During hypoglycaemia (mean PG 2.9 mmol/l), working memory performance was impaired. Altered performance was associated with significantly increased...
Nasal Colivelin treatment ameliorates memory impairment related to Alzheimer's disease.

Science.gov (United States)

Yamada, Marina; Chiba, Tomohiro; Sasabe, Jumpei; Terashita, Kenzo; Aiso, Sadakazu; Matsuoka, Masaaki

2008-07-01

Humanin (HN) and its derivatives, such as Colivelin (CLN), suppress neuronal death induced by insults related to Alzheimer's disease (AD) by activating STAT3 in vitro. They also ameliorate functional memory impairment of mice induced by anticholinergic drugs or soluble toxic amyloid-beta (Abeta) in vivo when either is directly administered into the cerebral ventricle or intraperitoneally injected. However, the mechanism underlying the in vivo effect remains uncharacterized. In addition, from the standpoint of clinical application, drug delivery methods that are less invasive and specific to the central nervous system (CNS) should be developed. In this study, we show that intranasally (i.n.) administered CLN can be successfully transferred to CNS via the olfactory bulb. Using several behavioral tests, we have demonstrated that i.n. administered CLN ameliorates memory impairment of AD models in a dose-responsive manner. Attenuation of AD-related memory impairment by HN derivatives such as CLN appears to be correlated with an increase in STAT3 phosphorylation levels in the septohippocampal region, suggesting that anti-AD activities of HN derivatives may be mediated by activation of STAT3 in vivo as they are in vitro. We further demonstrate that CLN treatment inhibits an Abeta induced decrease in the number of choline acetyltransferase (ChAT)-positive neurons in the medial septum. Combined with the finding that HN derivatives upregulate mRNA expression of neuronal ChAT and vesicular acetylcholine transporter (VAChT) in vitro, it is assumed that CLN may ameliorate memory impairment of AD models by supporting cholinergic neurotransmission, which is at least partly mediated by STAT3-mediated transcriptional upregulation of ChAT and VAChT.
Free and Cued Selective Reminding Test is superior to the Wechsler Memory Scale in discriminating mild cognitive impairment from Alzheimer's disease.

Science.gov (United States)

Lemos, Raquel; Cunha, Catarina; Marôco, João; Afonso, Ana; Simões, Mário R; Santana, Isabel

2015-08-01

The Logical Memory (LM) and the Verbal Paired Associative Learning (VPAL) are subtests from the Wechsler Memory Scale commonly used to characterize the memory deficit of amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD). The Free and Cued Selective Reminding Test (FCSRT) was suggested to assess the memory impairment of AD spectrum patients by the International Working Group on AD. In the present study, we compared the properties of the tests and their accuracy in classifying aMCI and AD. A group of aMCI patients (n = 85) and AD patients (n = 43) were included. The reliability and the validity of the three tests were analyzed. AD patients showed a significant pattern of worse impairment on all tests than aMCI. The FCSRT was able to classify more patients as having memory impairment in the aMCI group rather than the WMS subtests. The FCSRT proved to be good in discriminating the two groups in both lower and higher educational levels, whereas the LM was more useful in higher educated patients. Although the instruments had good results, the FCSRT was more accurate in discriminating MCI from AD, and less influenced by the educational level. © 2014 Japan Geriatrics Society.
Working Memory: A Selective Review.

Science.gov (United States)

Kent, Phillip L

2016-01-01

The purpose of this paper is to provide a selective overview of the evolution of the concept and assessment of working memory, and how its assessment has been confused with the assessment of some components of attention. A literature search using PsychNet Gold was conducted using the terms working memory. In addition, the writer reviewed recommendations from a sampling of recent neuropsychology texts in regard to the assessment of attention and working memory, as well as the two most recent editions of the Wechsler Memory Scale. It is argued that many clinicians have an incomplete understanding of the relationship between attention and working memory, and often conflate the two in assessment and treatment. Suggestions were made for assessing these abilities.
The accessibility of memory items in children’s working memory

OpenAIRE

Roome, Hannah; Towse, John

2016-01-01

This thesis investigates the processes and systems that support recall in working memory. In particular it seeks to apply ideas from the adult-based dual-memory framework (Unsworth & Engle, 2007b) that claims primary memory and secondary memory are independent contributors to working memory capacity. These two memory systems are described as domain-general processes that combine control of attention and basic memory abilities to retain information. The empirical contribution comprises five ex...
Can verbal working memory training improve reading?

Science.gov (United States)

Banales, Erin; Kohnen, Saskia; McArthur, Genevieve

2015-01-01

The aim of the current study was to determine whether poor verbal working memory is associated with poor word reading accuracy because the former causes the latter, or the latter causes the former. To this end, we tested whether (a) verbal working memory training improves poor verbal working memory or poor word reading accuracy, and whether (b) reading training improves poor reading accuracy or verbal working memory in a case series of four children with poor word reading accuracy and verbal working memory. Each child completed 8 weeks of verbal working memory training and 8 weeks of reading training. Verbal working memory training improved verbal working memory in two of the four children, but did not improve their reading accuracy. Similarly, reading training improved word reading accuracy in all children, but did not improve their verbal working memory. These results suggest that the causal links between verbal working memory and reading accuracy may not be as direct as has been assumed.
Working memory for meaningless manual gestures.

Science.gov (United States)

Rudner, Mary

2015-03-01

Effects on working memory performance relating to item similarity have been linked to prior categorisation of representations in long-term memory. However, there is evidence from gesture processing that this link may not be obligatory. The present study investigated whether working memory for incidentally generated meaningless manual gestures is influenced by formational similarity and whether this effect is modulated by working-memory load. Results showed that formational similarity did lower performance, demonstrating that similarity effects are not dependent on prior categorisation. However, this effect was only found when working-memory load was low, supporting a flexible resource allocation model according to which it is the quality rather than quantity of working memory representations that determines performance. This interpretation is in line with proposals suggesting language modality specific allocation of resources in working memory. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
Delayed Recall and Working Memory MMSE Domains Predict Delirium following Cardiac Surgery.

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Price, Catherine C; Garvan, Cynthia; Hizel, Loren P; Lopez, Marcos G; Billings, Frederic T

2017-01-01

Reduced preoperative cognition is a risk factor for postoperative delirium. The significance for type of preoperative cognitive deficit, however, has yet to be explored and could provide important insights into mechanisms and prediction of delirium. Our goal was to determine if certain cognitive domains from the general cognitive screener, the Mini-Mental State Exam (MMSE), predict delirium after cardiac surgery. Patients completed a preoperative MMSE prior to undergoing elective cardiac surgery. Following surgery, delirium was assessed throughout ICU stay using the Confusion Assessment Method for ICU delirium and the Richmond Agitation and Sedation Scale. Cardiac surgery patients who developed delirium (n = 137) had lower total MMSE scores than patients who did not develop delirium (n = 457). In particular, orientation to place, working memory, delayed recall, and language domain scores were lower. Of these, only the working memory and delayed recall domains predicted delirium in a regression model adjusting for history of chronic obstructive pulmonary disease, age, sex, and duration of cardiopulmonary bypass. For each word not recalled on the three-word delayed recall assessment, the odds of delirium increased by 50%. For each item missed on the working memory index, the odds of delirium increased by 36%. Of the patients who developed delirium, 47% had a primary impairment in memory, 21% in working memory, and 33% in both domains. The area under the receiver operating characteristics curve using only the working memory and delayed recall domains was 0.75, compared to 0.76 for total MMSE score. Delirium risk is greater for individuals with reduced MMSE scores on the delayed recall and working memory domains. Research should address why patients with memory and executive vulnerabilities are more prone to postoperative delirium than those with other cognitive limitations.
Everyday episodic memory in amnestic mild cognitive impairment: a preliminary investigation.

Science.gov (United States)

Irish, Muireann; Lawlor, Brian A; Coen, Robert F; O'Mara, Shane M

2011-08-04

Decline in episodic memory is one of the hallmark features of Alzheimer's disease (AD) and is also a defining feature of amnestic Mild Cognitive Impairment (MCI), which is posited as a potential prodrome of AD. While deficits in episodic memory are well documented in MCI, the nature of this impairment remains relatively under-researched, particularly for those domains with direct relevance and meaning for the patient's daily life. In order to fully explore the impact of disruption to the episodic memory system on everyday memory in MCI, we examined participants' episodic memory capacity using a battery of experimental tasks with real-world relevance. We investigated episodic acquisition and delayed recall (story-memory), associative memory (face-name pairings), spatial memory (route learning and recall), and memory for everyday mundane events in 16 amnestic MCI and 18 control participants. Furthermore, we followed MCI participants longitudinally to gain preliminary evidence regarding the possible predictive efficacy of these real-world episodic memory tasks for subsequent conversion to AD. The most discriminating tests at baseline were measures of acquisition, delayed recall, and associative memory, followed by everyday memory, and spatial memory tasks, with MCI patients scoring significantly lower than controls. At follow-up (mean time elapsed: 22.4 months), 6 MCI cases had progressed to clinically probable AD. Exploratory logistic regression analyses revealed that delayed associative memory performance at baseline was a potential predictor of subsequent conversion to AD. As a preliminary study, our findings suggest that simple associative memory paradigms with real-world relevance represent an important line of enquiry in future longitudinal studies charting MCI progression over time.
Everyday episodic memory in amnestic mild cognitive impairment: a preliminary investigation

Directory of Open Access Journals (Sweden)

Lawlor Brian A

2011-08-01

Full Text Available Abstract Background Decline in episodic memory is one of the hallmark features of Alzheimer's disease (AD and is also a defining feature of amnestic Mild Cognitive Impairment (MCI, which is posited as a potential prodrome of AD. While deficits in episodic memory are well documented in MCI, the nature of this impairment remains relatively under-researched, particularly for those domains with direct relevance and meaning for the patient's daily life. In order to fully explore the impact of disruption to the episodic memory system on everyday memory in MCI, we examined participants' episodic memory capacity using a battery of experimental tasks with real-world relevance. We investigated episodic acquisition and delayed recall (story-memory, associative memory (face-name pairings, spatial memory (route learning and recall, and memory for everyday mundane events in 16 amnestic MCI and 18 control participants. Furthermore, we followed MCI participants longitudinally to gain preliminary evidence regarding the possible predictive efficacy of these real-world episodic memory tasks for subsequent conversion to AD. Results The most discriminating tests at baseline were measures of acquisition, delayed recall, and associative memory, followed by everyday memory, and spatial memory tasks, with MCI patients scoring significantly lower than controls. At follow-up (mean time elapsed: 22.4 months, 6 MCI cases had progressed to clinically probable AD. Exploratory logistic regression analyses revealed that delayed associative memory performance at baseline was a potential predictor of subsequent conversion to AD. Conclusions As a preliminary study, our findings suggest that simple associative memory paradigms with real-world relevance represent an important line of enquiry in future longitudinal studies charting MCI progression over time.
Everyday episodic memory in amnestic Mild Cognitive Impairment: a preliminary investigation

LENUS (Irish Health Repository)

Irish, Muireann

2011-08-04

Abstract Background Decline in episodic memory is one of the hallmark features of Alzheimer\\'s disease (AD) and is also a defining feature of amnestic Mild Cognitive Impairment (MCI), which is posited as a potential prodrome of AD. While deficits in episodic memory are well documented in MCI, the nature of this impairment remains relatively under-researched, particularly for those domains with direct relevance and meaning for the patient\\'s daily life. In order to fully explore the impact of disruption to the episodic memory system on everyday memory in MCI, we examined participants\\' episodic memory capacity using a battery of experimental tasks with real-world relevance. We investigated episodic acquisition and delayed recall (story-memory), associative memory (face-name pairings), spatial memory (route learning and recall), and memory for everyday mundane events in 16 amnestic MCI and 18 control participants. Furthermore, we followed MCI participants longitudinally to gain preliminary evidence regarding the possible predictive efficacy of these real-world episodic memory tasks for subsequent conversion to AD. Results The most discriminating tests at baseline were measures of acquisition, delayed recall, and associative memory, followed by everyday memory, and spatial memory tasks, with MCI patients scoring significantly lower than controls. At follow-up (mean time elapsed: 22.4 months), 6 MCI cases had progressed to clinically probable AD. Exploratory logistic regression analyses revealed that delayed associative memory performance at baseline was a potential predictor of subsequent conversion to AD. Conclusions As a preliminary study, our findings suggest that simple associative memory paradigms with real-world relevance represent an important line of enquiry in future longitudinal studies charting MCI progression over time.
Does visuo-spatial working memory generally contribute to immediate serial letter recall?

Science.gov (United States)

Fürstenberg, A; Rummer, R; Schweppe, J

2013-01-01

This work contributes to the understanding of the visual similarity effect in verbal working memory, a finding that suggests that the visuo-spatial sketch pad-the system in Baddeley's working memory model specialised in retaining nonverbal visual information-might be involved in the retention of visually presented verbal materials. Crucially this effect is implicitly interpreted by the most influential theory of multimedia learning as evidence for an obligatory involvement of the visuo-spatial sketch pad. We claim that it is only involved when the functioning of the working memory component normally used for processing verbal material is impaired. In this article we review the studies that give rise to the idea of obligatory involvement of the visuo-spatial sketch pad and suggest that some findings can be understood with reference to orthographic rather than visual similarity. We then test an alternative explanation of the finding that is most apt to serve as evidence for obligatory involvement of the visuo-spatial sketch pad. We conclude that, in healthy adults and under normal learning conditions, the visual similarity effect can be explained within the framework of verbal working memory proposed by Baddeley (e.g., 1986, 2000) without additional premises regarding the visuo-spatial sketch.
Memory, Cognition and the Endogenous Evoked Potentials of the Brain: the Estimation of the Disturbance of Cognitive Functions and Capacity of Working Memory Without the Psychological Testing.

Science.gov (United States)

Gnezditskiy, V V; Korepina, O S; Chatskaya, A V; Klochkova, O I

2017-01-01

Cognition, cognitive and memory impairments is widely discussed in the literature, especially in the psycho physiological and the neurologic. In essence, this literature is dedicated to the psycho physiological tests, different scales. However, instrument neurophysiologic methods not so widely are used for these purposes. This review is dedicated to the instrument methods of neurophysiology, in particular to the endogenous evoked potentials method Р 300 (by characteristic latency 300 ms), in the estimation of cognitive functions and memory, to their special features dependent on age and to special features to their changes with the pathology. Method cognitive EP - Р 300 is the response of the brain, recorded under the conditions of the identification of the significant distinguishing stimulus, it facilitates the inspection of cognitive functions and memory in the healthy persons and patients with different manifestation of cognitive impairments. In the review it is shown on the basis of literature and our own data, that working (operative) memory and the capacity of the working memory it can be evaluated with the aid of the indices Р 300 within the normal subject and with the pathology. Testing with the estimation of working memory according to latent period of the peak Р 300 can be carried out and when conducting psychological testing is not possible for any reasons. Together with these cognitive EP are used for evidence pharmacotherapy of many neurotropic drugs.
Changing concepts of working memory

Science.gov (United States)

Ma, Wei Ji; Husain, Masud; Bays, Paul M

2014-01-01

Working memory is widely considered to be limited in capacity, holding a fixed, small number of items, such as Miller's ‘magical number’ seven or Cowan's four. It has recently been proposed that working memory might better be conceptualized as a limited resource that is distributed flexibly among all items to be maintained in memory. According to this view, the quality rather than the quantity of working memory representations determines performance. Here we consider behavioral and emerging neural evidence for this proposal. PMID:24569831
Glucose metabolism, gray matter structure, and memory decline in subjective memory impairment.

Science.gov (United States)

Scheef, Lukas; Spottke, Annika; Daerr, Moritz; Joe, Alexius; Striepens, Nadine; Kölsch, Heike; Popp, Julius; Daamen, Marcel; Gorris, Dominik; Heneka, Michael T; Boecker, Henning; Biersack, Hans J; Maier, Wolfgang; Schild, Hans H; Wagner, Michael; Jessen, Frank

2012-09-25

To identify biological evidence for Alzheimer disease (AD) in individuals with subjective memory impairment (SMI) and unimpaired cognitive performance and to investigate the longitudinal cognitive course in these subjects. [¹⁸F]fluoro-2-deoxyglucose PET (FDG-PET) and structural MRI were acquired in 31 subjects with SMI and 56 controls. Cognitive follow-up testing was performed (average follow-up time: 35 months). Differences in baseline brain imaging data and in memory decline were assessed between both groups. Associations of memory decline with brain imaging data were tested. The SMI group showed hypometabolism in the right precuneus and hypermetabolism in the right medial temporal lobe. Gray matter volume was reduced in the right hippocampus in the SMI group. At follow-up, subjects with SMI showed a poorer performance than controls on measures of episodic memory. Longitudinal memory decline in the SMI group was associated with reduced glucose metabolism in the right precuneus at baseline. The cross-sectional difference in 2 independent neuroimaging modalities indicates early AD pathology in SMI. The poorer memory performance at follow-up and the association of reduced longitudinal memory performance with hypometabolism in the precuneus at baseline support the concept of SMI as the earliest manifestation of AD.

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