Coleman, James R; Watson, Jason M; Strayer, David L
The present study investigated individual differences in information processing following errant behavior. Participants were initially classified as high or as low working memory capacity using the Operation Span Task. In a subsequent session, they then performed a high congruency version of the flanker task under both speed and accuracy stress. We recorded ERPs and behavioral measures of accuracy and response time in the flanker task with a primary focus on processing following an error. The error-related negativity was larger for the high working memory capacity group than for the low working memory capacity group. The positivity following an error (Pe) was modulated to a greater extent by speed-accuracy instruction for the high working memory capacity group than for the low working memory capacity group. These data help to explicate the neural bases of individual differences in working memory capacity and cognitive control. © 2017 Society for Psychophysiological Research.
Full Text Available This study investigated the effect of arousal on short-term relational memory and its underlying cortical network. Seventeen healthy participants performed a picture by location, short-term relational memory task using emotional pictures. Functional Magnetic Resonance Imaging was used to measure the BOLD signal relative to task. Subjects’ own ratings of the pictures were used to obtain subjective arousal ratings. Subjective arousal was found to have a dose-dependent effect on activations in the prefrontal cortex, amygdala, hippocampus and in higher order visual areas. Serial position analyses showed that high arousal trials produced a stronger primacy and recency effect than low arousal trials. The results indicate that short-term relational memory may be facilitated by arousal and that this may be modulated by a dose-response function in arousal-driven neuronal regions.
Thoresen, Christian; Jensen, Jimmy; Sigvartsen, Niels Petter B; Bolstad, Ingeborg; Server, Andres; Nakstad, Per H; Andreassen, Ole A; Endestad, Tor
This study investigated the effect of arousal on short-term relational memory and its underlying cortical network. Seventeen healthy participants performed a picture by location, short-term relational memory task using emotional pictures. Functional magnetic resonance imaging was used to measure the blood-oxygenation-level dependent signal relative to task. Subjects' own ratings of the pictures were used to obtain subjective arousal ratings. Subjective arousal was found to have a dose-dependent effect on activations in the prefrontal cortex, amygdala, hippocampus, and in higher order visual areas. Serial position analyses showed that high arousal trials produced a stronger primacy and recency effect than low arousal trials. The results indicate that short-term relational memory may be facilitated by arousal and that this may be modulated by a dose-response function in arousal-driven neuronal regions.
Kalanthroff, Eyal; Avnit, Amir; Henik, Avishai; Davelaar, Eddy J; Usher, Marius
Performance on the Stroop task reflects two types of conflict-informational (between the incongruent word and font color) and task (between the contextually relevant color-naming task and the irrelevant, but automatic, word-reading task). According to the dual mechanisms of control theory (DMC; Braver, 2012), variability in Stroop performance can result from variability in the deployment of a proactive task-demand control mechanism. Previous research has shown that when proactive control (PC) is diminished, both increased Stroop interference and a reversed Stroop facilitation (RF) are observed. Although the current DMC model accounts for the former effect, it does not predict the observed RF, which is considered to be behavioral evidence for task conflict in the Stroop task. Here we expanded the DMC model to account for Stroop RF. Assuming that a concurrent working memory (WM) task reduces PC, we predicted both increased interference and an RF. Nineteen participants performed a standard Stroop task combined with a concurrent n-back task, which was aimed at reducing available WM resources, and thus overloading PC. Although the results indicated common Stroop interference and facilitation in the low-load condition (zero-back), in the high-load condition (two-back), both increased Stroop interference and RF were observed, consistent with the model's prediction. These findings indicate that PC is modulated by concurrent WM load and serves as a common control mechanism for both informational and task Stroop conflicts.
Roozendaal, Benno; McGaugh, James L.
Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive evidence from both animal and human research indicates that emotionally significant experiences activate hormonal and brain systems that regulate the consolidation of newly acquired memories. These effects are integrated through noradrenergic activation of the basolateral amygdala which regulates memory consolidation via interactions with many other brain regions involved in consolidating memories of recent experiences. Modulatory systems not only influence neurobiological processes underlying the consolidation of new information, but also affect other mnemonic processes, including memory extinction, memory recall and working memory. In contrast to their enhancing effects on consolidation, adrenal stress hormones impair memory retrieval and working memory. Such effects, as with memory consolidation, require noradrenergic activation of the basolateral amygdala and interactions with other brain regions. PMID:22122145
Roozendaal, Benno; McGaugh, James L.
Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive
Full Text Available This study investigated the neural processing underlying the cognitive control of emotions induced by the presentation of task-irrelevant emotional pictures before a working memory task. Previous studies have suggested that the cognitive control of emotion involves the prefrontal regions. Therefore, we measured the hemodynamic responses that occurred in the prefrontal region with a 16-channel near-infrared spectroscopy (NIRS system. In our experiment, participants observed two negative or two neutral pictures in succession immediately before a 1-back or 3-back task. Pictures were selected from the International Affective Picture System. We measured the changes in the concentration of oxygenated hemoglobin (oxyHb during picture presentation and during the n-back task. The emotional valence of the picture affected the oxyHb changes in anterior parts of the medial prefrontal cortex (located in the left and right superior frontal gyrus and left inferior frontal gyrus during the n-back task; the oxyHb changes during the task were significantly greater following negative rather than neutral stimulation. As indicated in a number of previous studies, and the time courses of the oxyHb changes in our study, activation in these locations is possibly led by cognitive control of emotion, though we cannot deny it may simply be emotional responses. There were no effects of emotion on oxyHb changes during picture presentation or on n-back task performance. Although further studies are necessary to confirm this interpretation, our findings suggest that NIRS can be used to investigate neural processing during emotional control.
Seubert, Janina; Gregory, Kristen M; Chamberland, Jessica; Dessirier, Jean-Marc; Lundström, Johan N
Scented cosmetic products are used across cultures as a way to favorably influence one's appearance. While crossmodal effects of odor valence on perceived attractiveness of facial features have been demonstrated experimentally, it is unknown whether they represent a phenomenon specific to affective processing. In this experiment, we presented odors in the context of a face battery with systematic feature manipulations during a speeded response task. Modulatory effects of linear increases of odor valence were investigated by juxtaposing subsequent memory-based ratings tasks--one predominantly affective (attractiveness) and a second, cognitive (age). The linear modulation pattern observed for attractiveness was consistent with additive effects of face and odor appraisal. Effects of odor valence on age perception were not linearly modulated and may be the result of cognitive interference. Affective and cognitive processing of faces thus appear to differ in their susceptibility to modulation by odors, likely as a result of privileged access of olfactory stimuli to affective brain networks. These results are critically discussed with respect to potential biases introduced by the preceding speeded response task.
Fales, C L; Barch, D M; Burgess, G C; Schaefer, A; Mennin, D S; Gray, J R; Braver, T S
According to the processing-efficiency hypothesis (Eysenck, Derakshan, Santos, & Calvo, 2007), anxious individuals are thought to require greater activation of brain systems supporting cognitive control (e.g.,dorsolateral prefrontal cortex; DLPFC) in order to maintain equivalent performance to nonanxious subjects. A recent theory of cognitive control (Braver, Gray, & Burgess, 2007) has proposed that reduced cognitive efficiency might occur as a result of changes in the temporal dynamics of DLPFC recruitment. In this study, we used a mixed blocked/ event-related fMRI design to track transient and sustained activity in DLPFC while high- and low-anxious participants performed a working memory task. The task was performed after the participants viewed videos designed to induce neutral or anxiety-related moods. After the neutral video, the high-anxious participants had reduced sustained but increased transient activation in working memory areas, in comparison with low-anxious participants. The high-anxious group also showed extensive reductions in sustained activation of "default-network" areas (possible deactivation). After the negative video,the low-anxiety group shifted their activation dynamics in cognitive control regions to resemble those of the high-anxious group. These results suggest that reduced cognitive control in anxiety might be due to a transient, rather than sustained, pattern of working memory recruitment. Supplementary information for this study may be found at www.psychonomic.org/archive.
Spyrka, Jadwiga; Hess, Grzegorz
The consequences of stress depend on characteristics of the stressor, including the duration of exposure, severity, and predictability. Exposure of mice to repeated neck restraint has been shown to bidirectionally modulate the potential for long-term potentiation (LTP) in the dentate gyrus (DG) in a manner dependent on the number of restraint repetitions, but the influence of repeated brief neck restraint on electrophysiology of single DG neurons has not yet been investigated. Here, we aimed at finding the effects of 1, 3, 7, 14, or 21 daily neck restraint sessions lasting 10 min on electrophysiological characteristics of DG granule cells as well as excitatory and inhibitory synaptic inputs to these neurons. While the excitability of DG granule cells and inhibitory synaptic transmission were unchanged, neck restraint decreased the frequency of spontaneous excitatory currents after three repetitions but enhanced it after 14 and 21 repetitions. The consequences of repeated neck restraint on hippocampus-dependent memory were investigated using the object location test (OLT). Neck restraint stress impaired cognitive performance in the OLT after three repetitions but improved it after 14 and 21 repetitions. Mice subjected to three neck restraint sessions displayed an increase in the measures of depressive and anxiety-like behaviors, however, prolongation of the exposure to neck restraint resulted in a gradual decline in the intensity of these measures. These data indicate that stress imposed by an increasing number of repeated neck restraint episodes bidirectionally modulates both excitatory synaptic transmission in the DG and cognitive performance in the object location memory task. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.
easily be traced back to Baldwin (1894), one of Piaget’s early influences . Baldwin and others argued that memory span tasks reflect ability to maintain...very little impact on the number of words remembered . Craik et al. concluded from these studies that controlled attention is critical to memory ...REPORT TITLE: Final Technical Report for Grant Working memory , controlled attention and task switching is forwarded for your information
distinguished two forms of memory : deliberate recollection of prior events versus the unaware influence of prior events on the performance of a later task...attempts to remember information. The findings reported here contribute in particular to our understanding of the memory processes involved in hypothesis... influenced by prior exposure to relevant events. Indeed, since the prior events themselves often cannot be consciously retrieved, this latter form of memory
Rinne, Teemu; Koistinen, Sonja; Salonen, Oili; Alho, Kimmo
The functional organization of auditory cortex (AC) is still poorly understood. Previous studies suggest segregation of auditory processing streams for spatial and nonspatial information located in the posterior and anterior AC, respectively (Rauschecker and Tian, 2000; Arnott et al., 2004; Lomber and Malhotra, 2008). Furthermore, previous studies have shown that active listening tasks strongly modulate AC activations (Petkov et al., 2004; Fritz et al., 2005; Polley et al., 2006). However, the task dependence of AC activations has not been systematically investigated. In the present study, we applied high-resolution functional magnetic resonance imaging of the AC and adjacent areas to compare activations during pitch discrimination and n-back pitch memory tasks that were varied parametrically in difficulty. We found that anterior AC activations were increased during discrimination but not during memory tasks, while activations in the inferior parietal lobule posterior to the AC were enhanced during memory tasks but not during discrimination. We also found that wide areas of the anterior AC and anterior insula were strongly deactivated during the pitch memory tasks. While these results are consistent with the proposition that the anterior and posterior AC belong to functionally separate auditory processing streams, our results show that this division is present also between tasks using spatially invariant sounds. Together, our results indicate that activations of human AC are strongly dependent on the characteristics of the behavioral task.
Thomas, Paul M J; FitzGibbon, Lily; Raymond, Jane E
Learning allows the value of motivationally salient events to become associated with stimuli that predict those events. Here, we asked whether value associations could facilitate visual working memory (WM), and whether such effects would be valence dependent. Our experiment was specifically designed to isolate value-based effects on WM from value-based effects on selective attention that might be expected to bias encoding. In a simple associative learning task, participants learned to associate the color of tinted faces with gaining or losing money or neither. Tinted faces then served as memoranda in a face identity WM task for which previously learned color associations were irrelevant and no monetary outcomes were forthcoming. Memory was best for faces with gain-associated tints, poorest for faces with loss-associated tints, and average for faces with no-outcome-associated tints. Value associated with 1 item in the WM array did not modulate memory for other items in the array. Eye movements when studying faces did not depend on the valence of previously learned color associations, arguing against value-based biases being due to differential encoding. This valence-sensitive value-conditioning effect on WM appears to result from modulation of WM maintenance processes. (c) 2015 APA, all rights reserved).
Bluhm, Robyn L; Clark, C Richard; McFarlane, Alexander C; Moores, Kathryn A; Shaw, Marnie E; Lanius, Ruth A
The default network exhibits correlated activity at rest and has shown decreased activation during performance of cognitive tasks. There has been little investigation of changes in connectivity of this network during task performance. In this study, we examined task-related modulation of connectivity between two seed regions from the default network posterior cingulated cortex (PCC) and medial prefrontal cortex (mPFC) and the rest of the brain in 12 healthy adults. The purpose was to determine (1) whether connectivity within the default network differs between a resting state and performance of a cognitive (working memory) task and (2) whether connectivity differs between these nodes of the default network and other brain regions, particularly those implicated in cognitive tasks. There was little change in connectivity with the other main areas of the default network for either seed region, but moderate task-related changes in connectivity occurred between seed regions and regions outside the default network. For example, connectivity of the mPFC with the right insula and the right superior frontal gyrus decreased during task performance. Increased connectivity during the working memory task occurred between the PCC and bilateral inferior frontal gyri, and between the mPFC and the left inferior frontal gyrus, cuneus, superior parietal lobule, middle temporal gyrus and cerebellum. Overall, the areas showing greater correlation with the default network seed regions during task than at rest have been previously implicated in working memory tasks. These changes may reflect a decrease in the negative correlations occurring between the default and task-positive networks at rest. Copyright © 2010 Wiley-Liss, Inc.
Salvetti, Beatrice; Morris, Richard G.M.; Wang, Szu-Han
Many insignificant events in our daily life are forgotten quickly but can be remembered for longer when other memory-modulating events occur before or after them. This phenomenon has been investigated in animal models in a protocol in which weak memories persist longer if exploration in a novel context is introduced around the time of memory encoding. This study aims to understand whether other types of rewarding or novel tasks, such as rewarded learning in a T-maze and novel object recognition, can also be effective memory-modulating events. Rats were trained in a delayed matching-to-place task to encode and retrieve food locations in an event arena. Weak encoding with only one food pellet at the sample location induced memory encoding but forgetting over 24 h. When this same weak encoding was followed by a rewarded task in a T-maze, the memory persisted for 24 h. Moreover, the same persistence of memory over 24 h could be achieved by exploration in a novel box or by a rewarded T-maze task after a “non-rewarded” weak encoding. When the one-pellet weak encoding was followed by novel object exploration, the memory did not persist at 24 h. Together, the results confirm that place encoding is possible without explicit reward, and that rewarded learning in a separate task lacking novelty can be an effective memory-modulating event. The behavioral and neurobiological implications are discussed. PMID:24429424
Eric D Leshikar
Full Text Available Previous behavioral evidence suggests that instructed strategy use benefits associative memory formation in paired associate tasks. Two such effective encoding strategies--visual imagery and sentence generation--facilitate memory through the production of different types of mediators (e.g., mental images and sentences. Neuroimaging evidence suggests that regions of the brain support memory reflecting the mental operations engaged at the time of study. That work, however, has not taken into account self-reported encoding task success (i.e., whether participants successfully generated a mediator. It is unknown, therefore, whether task-selective memory effects specific to each strategy might be found when encoding strategies are successfully implemented. In this experiment, participants studied pairs of abstract nouns under either visual imagery or sentence generation encoding instructions. At the time of study, participants reported their success at generating a mediator. Outside of the scanner, participants further reported the quality of the generated mediator (e.g., images, sentences for each word pair. We observed task-selective memory effects for visual imagery in the left middle occipital gyrus, the left precuneus, and the lingual gyrus. No such task-selective effects were observed for sentence generation. Intriguingly, activity at the time of study in the left precuneus was modulated by the self-reported quality (vividness of the generated mental images with greater activity for trials given higher ratings of quality. These data suggest that regions of the brain support memory in accord with the encoding operations engaged at the time of study.
The present study explores the independent and interactive effects of task complexity and task modality on linguistic dimensions of second language (L2) performance and investigates how these effects are modulated by individual differences in working memory capacity. Thirty-two intermediate learners of L2 Spanish completed less and more complex…
Roy, Michael M.; Mitten, Scott T.; Christenfeld, Nicholas J. S.
People are often inaccurate in predicting task duration. The memory bias explanation holds that this error is due to people having incorrect memories of how long previous tasks have taken, and these biased memories cause biased predictions. Therefore, the authors examined the effect on increasing predictive accuracy of correcting memory through…
Full Text Available A wealth of experimental evidence suggests that working memory circuits preferentially represent information that is behaviorally relevant. Still, we are missing a mechanistic account of how these representations come about. Here we provide a simple explanation for a range of experimental findings, in light of prefrontal circuits adapting to task constraints by reward-dependent learning. In particular, we model a neural network shaped by reward-modulated spike-timing dependent plasticity (r-STDP and homeostatic plasticity (intrinsic excitability and synaptic scaling. We show that the experimentally-observed neural representations naturally emerge in an initially unstructured circuit as it learns to solve several working memory tasks. These results point to a critical, and previously unappreciated, role for reward-dependent learning in shaping prefrontal cortex activity.
Since Damasio introduced the somatic markers hypothesis in Damasio (1994), it has spread through the psychological community, where it is now commonly acknowledged that somatic states are a factor in producing the qualitative dimension of our experiences. Present actions are emotionally guided by those somatic states that were previously activated in similar experiences. In this model, somatic markers serve as a kind of embodied memory. Here, we test whether the manipulation of somatic markers can modulate the emotional evaluation of negative memories. Because facial feedback has been shown to be a powerful means of modifying emotional judgements, we used it to manipulate somatic markers. Participants first read a sad story in order to induce a negative emotional memory and then were asked to rate their emotions and memory about the text. Twenty-four hours later, the same participants were asked to assume a predetermined facial feedback (smiling) while reactivating their memory of the sad story. The participants were once again asked to fill in emotional and memory questionnaires about the text. Our results showed that participants who had smiled during memory reactivation later rated the text less negatively than control participants. However, the contraction of the zygomaticus muscles during memory reactivation did not have any impact on episodic memory scores. This suggests that manipulating somatic states modified emotional memory without affecting episodic memory. Thus, modulating memories through bodily states might pave the way to studying memory as an embodied function and help shape new kinds of psychotherapeutic interventions.
Ford, Jaclyn Hennessey; Rubin, David C.; Giovanello, Kelly S.
Older adults tend to retrieve autobiographical information that is overly general (i.e. not restricted to a single event, termed the overgenerality effect) relative to young adults’ specific memories. A vast majority of studies that have reported overgenerality effects explicitly instruct participants to retrieve specific memories, thereby requiring participants to maintain task goals, inhibit inappropriate responses, and control their memory search. Since these processes are impaired in healthy aging, it is important to determine whether such task instructions influence the magnitude of the overgenerality effect in older adults. In the current study, participants retrieved autobiographical memories during presentation of musical clips. Task instructions were manipulated to separate age-related differences in the specificity of underlying memory representations from age-related differences in following task instructions. Whereas young adults modulated memory specificity based on task demands, older adults did not. These findings suggest that reported rates of overgenerality in older adults’ memories may include age-related differences in memory representation, as well as differences in task compliance. Such findings provide a better understanding of the underlying cognitive mechanisms involved in age-related changes in autobiographical memory and may also be valuable for future research examining effects of overgeneral memory on general well-being. PMID:23915176
Ford, Jaclyn Hennessey; Rubin, David C; Giovanello, Kelly S
Older adults tend to retrieve autobiographical information that is overly general (i.e., not restricted to a single event, termed the overgenerality effect) relative to young adults' specific memories. A vast majority of studies that have reported overgenerality effects explicitly instruct participants to retrieve specific memories, thereby requiring participants to maintain task goals, inhibit inappropriate responses, and control their memory search. Since these processes are impaired in healthy ageing, it is important to determine whether such task instructions influence the magnitude of the overgenerality effect in older adults. In the current study participants retrieved autobiographical memories during presentation of musical clips. Task instructions were manipulated to separate age-related differences in the specificity of underlying memory representations from age-related differences in following task instructions. Whereas young adults modulated memory specificity based on task demands, older adults did not. These findings suggest that reported rates of overgenerality in older adults' memories might include age-related differences in memory representation, as well as differences in task compliance. Such findings provide a better understanding of the underlying cognitive mechanisms involved in age-related changes in autobiographical memory and may also be valuable for future research examining effects of overgeneral memory on general well-being.
Blois, J. de
A compact CAMAC memory module for experimental data handling was developed to eliminate the need of direct memory access in computer controlled measurements. When using autonomous controllers it also makes measurements more independent of the program and enlarges the available space for programs in the memory of the micro-computer. The memory module has three modes of operation: an increment-, a list- and a fifo mode. This is achieved by connecting the main parts, being: the memory (MEM), the fifo buffer (FIFO), the address buffer (BUF), two counters (AUX and ADDR) and a readout register (ROR), by an internal 24-bit databus. The time needed for databus operations is 1 μs, for measuring cycles as well as for CAMAC cycles. The FIFO provides temporary data storage during CAMAC cycles and separates the memory part from the application part. The memory is variable from 1 to 64K (24 bits) by using different types of memory chips. The application part, which forms 1/3 of the module, will be specially designed for each application and is added to the memory by an internal connector. The memory unit will be used in Moessbauer experiments and in thermal neutron scattering experiments. (orig.)
Solé Puig, Maria; Romeo, August; Cañete Crespillo, Jose; Supèr, Hans
In a previous report it was shown that covertly attending visual stimuli produce small convergence of the eyes, and that visual stimuli can give rise to different modulations of the angle of eye vergence, depending on their power to capture attention. Working memory is highly dependent on attention. Therefore, in this study we assessed vergence responses in a memory task. Participants scanned a set of 8 or 12 images for 10 s, and thereafter were presented with a series of single images. One half were repeat images - that is, they belonged to the initial set - and the other half were novel images. Participants were asked to indicate whether or not the images were included in the initial image set. We observed that eyes converge during scanning the set of images and during the presentation of the single images. The convergence was stronger for remembered images compared with the vergence for nonremembered images. Modulation in pupil size did not correspond to behavioural responses. The correspondence between vergence and coding/retrieval processes of memory strengthen the idea of a role for vergence in attention processing of visual information.
Dampure, Julien; Benraiss, Abdelrhani; Vibert, Nicolas
During visual search for words, the impact of the visual and semantic features of words varies as a function of the search task. This event-related potential (ERP) study focused on the way these features of words are used to detect similarities between the distractor words that are glanced at and the target word, as well as to then reject the distractor words. The participants had to search for a target word that was either given literally or defined by a semantic clue among words presented sequentially. The distractor words included words that resembled the target and words that were semantically related to the target. The P2a component was the first component to be modulated by the visual and/or semantic similarity of distractors to the target word, and these modulations varied according to the task. The same held true for the later N300 and N400 components, which confirms that, depending on the task, distinct processing pathways were sensitized through attentional modulation. Hence, the process that matches what is perceived with the target acts during the first 200 ms after word presentation, and both early detection and late rejection processes of words depend on the search task and on the representation of the target stored in memory.
Full Text Available A shared memory module connecting multiple independently clocked processors is presented. The memory module itself is independently clocked, supports hardware address generation, mutual exclusion, and multiple addressing modes. The architecture supports independent address generation and data generation/consumption by different processors which increases efficiency and simplifies programming for many embedded and DSP tasks. Simultaneous access by different processors is arbitrated using a least-recently-serviced priority scheme. Simulations show high throughputs over a variety of memory loads. A standard cell implementation shares an 8 K-word SRAM among four processors, and can support a 64 K-word SRAM with no additional changes. It cycles at 555 MHz and occupies 1.2 mm2 in 0.18 μm CMOS.
Papenberg, Goran; Becker, Nina; Ferencz, Beata; Naveh-Benjamin, Moshe; Laukka, Erika J; Bäckman, Lars; Brehmer, Yvonne
Previous research shows that associative memory declines more than item memory in aging. Although the underlying mechanisms of this selective impairment remain poorly understood, animal and human data suggest that dopaminergic modulation may be particularly relevant for associative binding. We investigated the influence of dopamine (DA) receptor genes on item and associative memory in a population-based sample of older adults (n = 525, aged 60 years), assessed with a face-scene item associative memory task. The effects of single-nucleotide polymorphisms of DA D1 (DRD1; rs4532), D2 (DRD2/ANKK1/Taq1A; rs1800497), and D3 (DRD3/Ser9Gly; rs6280) receptor genes were examined and combined into a single genetic score. Individuals carrying more beneficial alleles, presumably associated with higher DA receptor efficacy (DRD1 C allele; DRD2 A2 allele; DRD3 T allele), performed better on associative memory than persons with less beneficial genotypes. There were no effects of these genes on item memory or other cognitive measures, such as working memory, executive functioning, fluency, and perceptual speed, indicating a selective association between DA genes and associative memory. By contrast, genetic risk for Alzheimer disease (AD) was associated with worse item and associative memory, indicating adverse effects of APOE ε4 and a genetic risk score for AD (PICALM, BIN1, CLU) on episodic memory in general. Taken together, our results suggest that DA may be particularly important for associative memory, whereas AD-related genetic variations may influence overall episodic memory in older adults without dementia.
Deprez, Sabine; Vandenbulcke, Mathieu; Peeters, Ron; Emsell, Louise; Amant, Frederic; Sunaert, Stefan
Insight into the neural architecture of multitasking is crucial when investigating the pathophysiology of multitasking deficits in clinical populations. Presently, little is known about how the brain combines dual-tasking with a concurrent short-term memory task, despite the relevance of this mental operation in daily life and the frequency of complaints related to this process, in disease. In this study we aimed to examine how the brain responds when a memory task is added to dual-tasking. Thirty-three right-handed healthy volunteers (20 females, mean age 39.9 ± 5.8) were examined with functional brain imaging (fMRI). The paradigm consisted of two cross-modal single tasks (a visual and auditory temporal same-different task with short delay), a dual-task combining both single tasks simultaneously and a multi-task condition, combining the dual-task with an additional short-term memory task (temporal same-different visual task with long delay). Dual-tasking compared to both individual visual and auditory single tasks activated a predominantly right-sided fronto-parietal network and the cerebellum. When adding the additional short-term memory task, a larger and more bilateral frontoparietal network was recruited. We found enhanced activity during multitasking in components of the network that were already involved in dual-tasking, suggesting increased working memory demands, as well as recruitment of multitask-specific components including areas that are likely to be involved in online holding of visual stimuli in short-term memory such as occipito-temporal cortex. These results confirm concurrent neural processing of a visual short-term memory task during dual-tasking and provide evidence for an effective fMRI multitasking paradigm. © 2013 Elsevier Ltd. All rights reserved.
Full Text Available Lesions of the entorhinal cortex produce retrograde memory impairment in both animals and humans. Here we report the effects of bilateral entorhinal cortex lesions caused by the stereotaxic infusion of N-methyl-D-aspartate (NMDA in rats at two different moments, before or after the training session, on memory of different tasks: two-way shuttle avoidance, inhibitory avoidance and habituation to an open field. Pre- or post-training entorhinal cortex lesions caused an impairment of performance in the shuttle avoidance task, which agrees with the previously described role of this area in the processing of memories acquired in successive sessions. In the inhibitory avoidance task, only the post-training lesions had an effect (amnesia. No effect was observed on the open field task. The findings suggest that the role of the entorhinal cortex in memory processing is task-dependent, perhaps related to the complexity of each task
Saraiva, Magda; Albuquerque, Pedro B.; Arantes, Joana
Studies on collaborative memory have revealed an interesting phenomenon called collaborative inhibition (CI) (i.e., nominal groups recall more information than collaborative groups). However, the results of studies on false memories in collaborative memory tasks are controversial. This study aimed to understand the production of false memories in…
Regan, J. E.
Two hypotheses concerning the way in which short-term memory interacts with another task in a dual task situation are considered. It is noted that when two tasks are combined, the activity of controlling and organizing performance on both tasks simultaneously may compete with either task for a resource; this resource may be space in a central mechanism or general processing capacity or it may be some task-specific resource. If a special relationship exists between short-term memory and control, especially if there is an identity relationship between short-term and a central controlling mechanism, then short-term memory performance should show a decrement in a dual task situation. Even if short-term memory does not have any particular identity with a controlling mechanism, but both tasks draw on some common resource or resources, then a tradeoff between the two tasks in allocating resources is possible and could be reflected in performance. The persistent concurrence cost in memory performance in these experiments suggests that short-term memory may have a unique status in the information processing system.
Bruss, Peter J; Mitchell, David B
The nature of various memory systems was examined using factor analysis. We reanalyzed data from 11 memory tasks previously reported in Mitchell and Bruss (2003). Four well-defined factors emerged, closely resembling episodic and semantic memory and conceptual and perceptual implicit memory, in line with both memory systems and transfer-appropriate processing accounts. To explore taxonomic issues, we ran separate analyses on the implicit tasks. Using a cross-format manipulation (pictures vs. words), we identified 3 prototypical tasks. Word fragment completion and picture fragment identification tasks were "factor pure," tapping perceptual processes uniquely. Category exemplar generation revealed its conceptual nature, yielding both cross-format priming and a picture superiority effect. In contrast, word stem completion and picture naming were more complex, revealing attributes of both processes.
Rudebeck, Sarah R; Bor, Daniel; Ormond, Angharad; O'Reilly, Jill X; Lee, Andy C H
One current challenge in cognitive training is to create a training regime that benefits multiple cognitive domains, including episodic memory, without relying on a large battery of tasks, which can be time-consuming and difficult to learn. By giving careful consideration to the neural correlates underlying episodic and working memory, we devised a computerized working memory training task in which neurologically healthy participants were required to monitor and detect repetitions in two streams of spatial information (spatial location and scene identity) presented simultaneously (i.e. a dual n-back paradigm). Participants' episodic memory abilities were assessed before and after training using two object and scene recognition memory tasks incorporating memory confidence judgments. Furthermore, to determine the generalizability of the effects of training, we also assessed fluid intelligence using a matrix reasoning task. By examining the difference between pre- and post-training performance (i.e. gain scores), we found that the trainers, compared to non-trainers, exhibited a significant improvement in fluid intelligence after 20 days. Interestingly, pre-training fluid intelligence performance, but not training task improvement, was a significant predictor of post-training fluid intelligence improvement, with lower pre-training fluid intelligence associated with greater post-training gain. Crucially, trainers who improved the most on the training task also showed an improvement in recognition memory as captured by d-prime scores and estimates of recollection and familiarity memory. Training task improvement was a significant predictor of gains in recognition and familiarity memory performance, with greater training improvement leading to more marked gains. In contrast, lower pre-training recollection memory scores, and not training task improvement, led to greater recollection memory performance after training. Our findings demonstrate that practice on a single
Sarah R Rudebeck
Full Text Available One current challenge in cognitive training is to create a training regime that benefits multiple cognitive domains, including episodic memory, without relying on a large battery of tasks, which can be time-consuming and difficult to learn. By giving careful consideration to the neural correlates underlying episodic and working memory, we devised a computerized working memory training task in which neurologically healthy participants were required to monitor and detect repetitions in two streams of spatial information (spatial location and scene identity presented simultaneously (i.e. a dual n-back paradigm. Participants' episodic memory abilities were assessed before and after training using two object and scene recognition memory tasks incorporating memory confidence judgments. Furthermore, to determine the generalizability of the effects of training, we also assessed fluid intelligence using a matrix reasoning task. By examining the difference between pre- and post-training performance (i.e. gain scores, we found that the trainers, compared to non-trainers, exhibited a significant improvement in fluid intelligence after 20 days. Interestingly, pre-training fluid intelligence performance, but not training task improvement, was a significant predictor of post-training fluid intelligence improvement, with lower pre-training fluid intelligence associated with greater post-training gain. Crucially, trainers who improved the most on the training task also showed an improvement in recognition memory as captured by d-prime scores and estimates of recollection and familiarity memory. Training task improvement was a significant predictor of gains in recognition and familiarity memory performance, with greater training improvement leading to more marked gains. In contrast, lower pre-training recollection memory scores, and not training task improvement, led to greater recollection memory performance after training. Our findings demonstrate that practice
Méndez-Couz, Marta; Conejo, Nélida M; Vallejo, Guillermo; Arias, Jorge L
Several studies suggest a prefrontal cortex involvement during the acquisition and consolidation of spatial memory, suggesting an active modulating role at late stages of acquisition processes. Recently, we have reported that the prelimbic and infralimbic areas of the prefrontal cortex, among other structures, are also specifically involved in the late phases of spatial memory extinction. This study aimed to evaluate whether the inactivation of the prelimbic area of the prefrontal cortex impaired spatial memory extinction. For this purpose, male Wistar rats were implanted bilaterally with cannulae into the prelimbic region of the prefrontal cortex. Animals were trained during 5 consecutive days in a hidden platform task and tested for reference spatial memory immediately after the last training session. One day after completing the training task, bilateral infusion of the GABAA receptor agonist Muscimol was performed before the extinction protocol was carried out. Additionally, cytochrome c oxidase histochemistry was applied to map the metabolic brain activity related to the spatial memory extinction under prelimbic cortex inactivation. Results show that animals acquired the reference memory task in the water maze, and the extinction task was successfully completed without significant impairment. However, analysis of the functional brain networks involved by cytochrome oxidase activity interregional correlations showed changes in brain networks between the group treated with Muscimol as compared to the saline-treated group, supporting the involvement of the mammillary bodies at a the late stage in the memory extinction process. Copyright © 2015 Elsevier B.V. All rights reserved.
de Chastelaine, Marianne; Mattson, Julia T; Wang, Tracy H; Donley, Brian E; Rugg, Michael D
The present fMRI experiment employed associative recognition to investigate the relationships between age and encoding-related negative subsequent memory effects and task-negative effects. Young, middle-aged and older adults (total n=136) were scanned while they made relational judgments on visually presented word pairs. In a later memory test, the participants made associative recognition judgments on studied, rearranged (items studied on different trials) and new pairs. Several regions, mostly localized to the default mode network, demonstrated negative subsequent memory effects in an across age-group analysis. All but one of these regions also demonstrated task-negative effects, although there was no correlation between the size of the respective effects. Whereas negative subsequent memory effects demonstrated a graded attenuation with age, task-negative effects declined markedly between the young and the middle-aged group, but showed no further reduction in the older group. Negative subsequent memory effects did not correlate with memory performance within any age group. By contrast, in the older group only, task-negative effects predicted later memory performance. The findings demonstrate that negative subsequent memory and task-negative effects depend on dissociable neural mechanisms and likely reflect distinct cognitive processes. The relationship between task-negative effects and memory performance in the older group might reflect the sensitivity of these effects to variations in amount of age-related neuropathology. This article is part of a Special Issue entitled SI: Memory. Copyright © 2014 Elsevier B.V. All rights reserved.
Full Text Available The generation of long-term memory for motor skills can be modulated by subsequent motor experiences that interfere with the consolidation process. Recent studies suggest that even a non-motor task may adversely affect some aspects of motor sequence memory. Here we show that motor sequence memory can be either enhanced or reduced, by different cognitive tasks. Participants were trained in performing finger movement sequences. Fully explicit instructions about the target sequence were given before practice. The buildup of procedural knowledge was tested at three time-points: immediately before training (T1, after practice (T2, and 24 hours later (T3. Each participant performed the task on two separate occasions; training on a different movement sequence on each occasion. In one condition, interference, participants performed a non-motor task immediately after T2. Half the participants solved simple math problems and half performed a simple semantic judgment task. In the baseline condition there was no additional task. All participants improved significantly between T1 and T2 (within-session gains. In addition, in the baseline condition, performance significantly improved between T2 and T3 (delayed 'off-line' gains. Solving math problems significantly enhanced these delayed gains in motor performance, whereas performing semantic decisions significantly reduced delayed gains compared to baseline. Thus, procedural motor memory consolidation can be either enhanced or inhibited by subsequent cognitive experiences. These effects do not require explicit or implicit new learning. The retrieval of unrelated, non-motor, well established knowledge can modulate procedural memory.
Eight sets of studies are reported that support a model my colleagues and I have developed which views WM as a system consisting of those long-term memory traces active above threshold, the procedures...
McIntyre, Christa K.; McGaugh, James L.; Williams, Cedric L.
Emotional arousal influences the consolidation of long-term memory. This review discusses experimental approaches and relevant findings that provide the foundation for current understanding of coordinated interactions between arousal activated peripheral hormones and the brain processes that modulate memory formation. Rewarding or aversive experiences release the stress hormones epinephrine (adrenalin) and glucocorticoids from the adrenal glands into the bloodstream. The effect of these hormones on memory consolidation depends upon binding of norepinephrine to beta-adrenergic receptors in the basolateral complex of the amygdala (BLA). Much evidence indicates that the stress hormones influence release of norepinephrine in the BLA through peripheral actions on the vagus nerve which stimulates, through polysynaptic connections, cells of the locus coeruleus to release norepinephrine. The BLA influences memory storage by actions on synapses, distributed throughout the brain, that are engaged in sensory and cognitive processing at the time of amygdala activation. The implications of the activation of these stress-activated memory processes are discussed in relation to stress-related memory disorders. PMID:22085800
Liu, Ding; Gu, Xiaowei; Zhu, Jia; Zhang, Xiaoxing; Han, Zhe; Yan, Wenjun; Cheng, Qi; Hao, Jiang; Fan, Hongmei; Hou, Ruiqing; Chen, Zhaoqin; Chen, Yulei; Li, Chengyu T
Cognitive processes require working memory (WM) that involves a brief period of memory retention known as the delay period. Elevated delay-period activity in the medial prefrontal cortex (mPFC) has been observed, but its functional role in WM tasks remains unclear. We optogenetically suppressed or enhanced activity of pyramidal neurons in mouse mPFC during the delay period. Behavioral performance was impaired during the learning phase but not after the mice were well trained. Delay-period mPFC activity appeared to be more important in memory retention than in inhibitory control, decision-making, or motor selection. Furthermore, endogenous delay-period mPFC activity showed more prominent modulation that correlated with memory retention and behavioral performance. Thus, properly regulated mPFC delay-period activity is critical for information retention during learning of a WM task. Copyright © 2014, American Association for the Advancement of Science.
José Luis Ventura-León
Full Text Available The purpose of the study is determine the relationship between a group of writing tasks and the immediate auditory memory, as well as to establish differences according to sex and level of study. Two hundred and three schoolchildren of fifth and sixth of elementary education from Lima (Peru participated, they were selected by a non-probabilistic sample. The Immediate Auditory Memory Test and the Battery for Evaluation of Writing Processes (known in Spanish as PROESC were used. Central tendency measures were used for descriptive analysis. We employed the Mann-Whitney U test, Spearman Rho test and probability of superiority as effect size measurement for the inferential analysis. The results indicated a moderate direct and significant correlation between writing tasks and immediate auditory memory in general way and low correlations between dimensions. Finally, it showed that the differences in immediate auditory memory and writing tasks according to sex and level of study does not have practical significance.
Smith, Rebekah E; Hunt, R Reed
Remembering to perform an action in the future, called prospective memory, often shows age-related differences in favor of young adults when tested in the laboratory. Recently Smith, Horn, and Bayen (2012; Aging, Neuropsychology, and Cognition, 19, 495) embedded a PM task in an ongoing color-matching task and manipulated the difficulty of the ongoing task by varying the number of colors on each trial of the task. Smith et al. found that age-related differences in PM performance (lower PM performance for older adults relative to young adults) persisted even when older adults could perform the ongoing task as well or better than the young adults. The current study investigates a possible explanation for the pattern of results reported by Smith et al. by including a manipulation of task emphasis: for half of the participants the prospective memory task was emphasize, while for the other half the ongoing color-matching task was emphasized. Older adults performed a 4-color version of the ongoing color-matching task, while young adults completed either the 4-color or a more difficult 6-color version of the ongoing task. Older adults failed to perform as well as the young adults on the prospective memory task regardless of task emphasis, even when older adults were performing as well or better than the young adults on the ongoing color-matching task. The current results indicate that the lack of an effect of ongoing task load on prospective memory task performance is not due to a perception that one or the other task is more important than the other.
Full Text Available The utilization of game elements in a non-game context is currently used in a vast range of different domains. However, research on game elements’ effects in cognitive tasks is still sparse. Thus, in this study we implemented three game elements, namely, progress bar, level indicator, and a thematic setting, in a working memory training task. We evaluated the impact of game elements on user performance and perceived state of flow when compared to a conventional version of the task. Participants interacting with game elements showed higher scores in the working memory training task than participants from a control group who completed the working memory training task without the game elements. Moreover, game elements facilitated the individuals’ performance closer to their maximum working memory capacity. Finally, the perceived flow did not differ between the two groups, which indicates that game elements can induce better performance without changing the perception of being “in the zone”, that is without an increase in anxiety or boredom. This empirical study indicates that certain game elements can improve the performance and efficiency in a working memory task by increasing users’ ability and willingness to train at their optimal performance level.
Manuel Ninaus; Gonçalo Pereira; René Stefitz; Rui Prada; Ana Paiva; Christa Neuper; Guilherme Wood
The utilization of game elements in a non-game context is currently used in a vast range of different domains. However, research on game elements’ effects in cognitive tasks is still sparse. Thus, in this study we implemented three game elements, namely, progress bar, level indicator, and a thematic setting, in a working memory training task. We evaluated the impact of game elements on user performance and perceived state of flow when compared to a conventional version of the task. Participan...
Morey, Candice C.; Morey, Richard D.; van der Reijden, Madeleine; Holweg, Margot
Observations of higher dual-task costs for within-domain than cross-domain task combinations constitute classic evidence for multi-component models of working memory (e.g., Baddeley, 1986; Logie, 2011). However, we report an asymmetric pattern of interference between verbal and visual-spatial tasks,
Full Text Available Working memory (WM is tightly capacity limited, it requires selective information gating, active information maintenance, and rapid active updating. Hence performing a WM task needs rapid and controlled transitions between neural persistent activity and the resting state. We propose that changes in spike-time correlations in neural activity provides a mechanism for the required working memory operations. As a proof of principle, we implement sustained activity and working memory in a recurrently-coupled spiking network with neurons receiving excitatory random background activity where background correlations are induced by a common noise source. We first characterize how the level of background correlations controls the stability of the persistent state. With sufficiently high correlations, the sustained state becomes practically unstable, so it cannot be initiated by a transient stimulus. We exploit this in a working memory model implementing the delay match to sample task by modulating flexibly in time the correlation level at different phases of the task. The modulation sets the network in different working regimes: more prompt to gate in a signal or clear the memory. The findings presented in this manuscript can form the basis for a new paradigm about how correlations are flexibly controlled by the cortical circuits to execute WM operations.
Zhao, Y; Tang, D; Hu, L; Zhang, L; Hitchman, G; Wang, L; Chen, A
Working memory (WM) tasks may increase or decrease the interference effect of concurrently performed cognitive control tasks. However, the neural oscillatory correlates of this modulation effect of WM on the Stroop task are still largely unknown. In the present study, behavioral and electroencephalographic (EEG) data were recorded from 32 healthy participants during their performance of the single Stroop task and the same task with a concurrent WM task. We observed that the Stroop interference effect represented in both response times (RTs) and theta-band event-related spectral perturbation (ERSP) magnitude reduced under the dual-task condition compared with the single-task condition. The reduction of interference in theta-band ERSP was further positively correlated with interference reduction in RTs, and was mainly explained by the source in the left middle frontal gyrus. In conclusion, the present study suggests that the effect of concurrent WM tasks on the reduction of the Stroop interference effect can be indexed by EEG oscillations in theta-band rhythm in the centro-frontal regions and this modulation was mediated by the reduced cognitive control under the concurrent WM task. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.
Sheremata, Summer L; Shomstein, Sarah
Successful interaction with the environment requires the ability to flexibly allocate resources to different locations in the visual field. Recent evidence suggests that visual short-term memory (VSTM) resources are distributed asymmetrically across the visual field based upon task demands. Here, we propose that context, rather than the stimulus itself, determines asymmetrical distribution of VSTM resources. To test whether context modulates the reallocation of resources to the right visual field, task set, defined by memory-load, was manipulated to influence visual short-term memory performance. Performance was measured for single-feature objects embedded within predominantly single- or two-feature memory blocks. Therefore, context was varied to determine whether task set directly predicts changes in visual field biases. In accord with the dynamic reallocation of resources hypothesis, task set, rather than aspects of the physical stimulus, drove improvements in performance in the right- visual field. Our results show, for the first time, that preparation for upcoming memory demands directly determines how resources are allocated across the visual field.
Botto, Marta; Basso, Demis; Ferrari, Marcella; Palladino, Paola
This study aimed to investigate updating in working memory (WM), analyzing the effects of task demand and memory resources on serial position curve (SPC), in a running memory task with slow pace presentation and a probed recognition procedure. These task conditions were supposed to produce an easier WM updating task, which may allow evidencing whether the task is performed through an active or a passive updating. Serial position curves were compared in conditions of high or low memory load, and with or without interference of a secondary (prospective memory, PM) task. With either a high WM load, or a high PM load, results showed a SPC with both primacy and recency effects, indicating the use of an active strategy. When resources were taken up by both PM task and high WM demand the usual pattern with only recency effect was obtained. Taken together, these findings support the ideas that 1--people can effectively update WM, and 2--the performance is dependent on both memory and executive resource availability. Copyright © 2014 Elsevier B.V. All rights reserved.
Full Text Available Memory performance is the result of many distinct mental processes, such as memory encoding, forgetting, and modulation of memory strength by emotional arousal. These processes, which are subserved by partly distinct molecular profiles, are not always amenable to direct observation. Therefore, computational models can be used to make inferences about specific mental processes and to study their genetic underpinnings. Here we combined a computational model-based analysis of memory-related processes with high density genetic information derived from a genome-wide study in healthy young adults. After identifying the best-fitting model for a verbal memory task and estimating the best-fitting individual cognitive parameters, we found a common variant in the gene encoding the brain-specific angiogenesis inhibitor 1-associated protein 2 (BAIAP2 that was related to the model parameter reflecting modulation of verbal memory strength by negative valence. We also observed an association between the same genetic variant and a similar emotional modulation phenotype in a different population performing a picture memory task. Furthermore, using functional neuroimaging we found robust genotype-dependent differences in activity of the parahippocampal cortex that were specifically related to successful memory encoding of negative versus neutral information. Finally, we analyzed cortical gene expression data of 193 deceased subjects and detected significant BAIAP2 genotype-dependent differences in BAIAP2 mRNA levels. Our findings suggest that model-based dissociation of specific cognitive parameters can improve the understanding of genetic underpinnings of human learning and memory.
Luksys, Gediminas; Ackermann, Sandra; Coynel, David; Fastenrath, Matthias; Gschwind, Leo; Heck, Angela; Rasch, Bjoern; Spalek, Klara; Vogler, Christian; Papassotiropoulos, Andreas; de Quervain, Dominique
Memory performance is the result of many distinct mental processes, such as memory encoding, forgetting, and modulation of memory strength by emotional arousal. These processes, which are subserved by partly distinct molecular profiles, are not always amenable to direct observation. Therefore, computational models can be used to make inferences about specific mental processes and to study their genetic underpinnings. Here we combined a computational model-based analysis of memory-related processes with high density genetic information derived from a genome-wide study in healthy young adults. After identifying the best-fitting model for a verbal memory task and estimating the best-fitting individual cognitive parameters, we found a common variant in the gene encoding the brain-specific angiogenesis inhibitor 1-associated protein 2 (BAIAP2) that was related to the model parameter reflecting modulation of verbal memory strength by negative valence. We also observed an association between the same genetic variant and a similar emotional modulation phenotype in a different population performing a picture memory task. Furthermore, using functional neuroimaging we found robust genotype-dependent differences in activity of the parahippocampal cortex that were specifically related to successful memory encoding of negative versus neutral information. Finally, we analyzed cortical gene expression data of 193 deceased subjects and detected significant BAIAP2 genotype-dependent differences in BAIAP2 mRNA levels. Our findings suggest that model-based dissociation of specific cognitive parameters can improve the understanding of genetic underpinnings of human learning and memory.
Yanes, Paula K; Roberts, John E; Carlos, Erica L
Considerable previous research has shown that retrieval of overgeneral autobiographical memories (OGM) is elevated among individuals suffering from various emotional disorders and those with a history of trauma. Although previous theories suggest that OGM serves the function of regulating acute negative affect, it is also possible that OGM results from difficulties in keeping the instruction set for the Autobiographical Memory Test (AMT) in working memory, or what has been coined "secondary goal neglect" (Dalgleish, 2004). The present study tested whether OGM is associated with poor memory for the task's instruction set, and whether an instruction set reminder would improve memory specificity over repeated trials. Multilevel modelling data-analytic techniques demonstrated a significant relationship between poor recall of instruction set and probability of retrieving OGMs. Providing an instruction set reminder for the AMT relative to a control task's instruction set improved memory specificity immediately afterward.
Schaper, Philipp; Grundgeiger, Tobias
Individuals frequently retrieve an intention, but the execution of the task needs to be delayed due to ongoing task demands - so-called delay-execute prospective memory (PM) tasks. We investigated commission errors in the delay-execute paradigm. Participants were told that a PM task is finished (PM task has been executed and is now finished for a final phase) or cancelled (PM task has been cancelled immediately after introduction). We observed commission errors and ongoing task performance in the final phase which included several irrelevant PM cues. In two experiments, we observed significantly more commission errors for cancelled compared to the finished intentions. In Experiment 2, commission errors were eliminated if the final phase required divided attention, regardless of PM task status. In addition, we observed significantly more PM cue interference on the ongoing task in the cancelled compared to the finished group, indicating that the PM task was retrieved in the cancelled group but not in the finished group. As retrieval and execution of the PM task were separated by a delay, the results indicate that commission errors are not always the result of a quick, spontaneous retrieval-execution sequence and may also occur when retrieval and execution are temporally separated.
Dalmaso, Mario; Castelli, Luigi; Scatturin, Pietro; Galfano, Giovanni
Microsaccades are tiny eye movements that individuals perform unconsciously during fixation. Despite that the nature and the functions of microsaccades are still lively debated, recent evidence has shown an association between these micro eye movements and higher order cognitive processes. Here, in two experiments, we specifically focused on working memory and addressed whether differential memory load could be reflected in a modulation of microsaccade dynamics. In Experiment 1, participants memorized a numerical sequence composed of either two (low-load condition) or five digits (high-load condition), appearing at fixation. The results showed a reduction in the microsaccadic rate in the high-load compared to the low-load condition. In Experiment 2, five red or green digits were always presented at fixation. Participants either memorized the color (low-load condition) or the five digits (high-load condition). Hence, visual stimuli were exactly the same in both conditions. Consistent with Experiment 1, microsaccadic rate was lower in the high-load than in the low-load condition. Overall, these findings reveal that an engagement of working memory can have an impact on microsaccadic rate, consistent with the view that microsaccade generation is pervious to top-down processes.
Hafiz, Md Abdullah Al
In this paper, we experimentally demonstrate a mechanical memory device based on the nonlinear dynamics of an electrostatically actuated microelectromechanical resonator utilizing an electrothermal frequency modulation scheme. The microstructure is deliberately fabricated as an in-plane shallow arch to achieve geometric quadratic nonlinearity. We exploit this inherent nonlinearity of the arch and drive it at resonance with minimal actuation voltage into the nonlinear regime, thereby creating softening behavior, hysteresis, and coexistence of states. The hysteretic frequency band is controlled by the electrothermal actuation voltage. Binary values are assigned to the two allowed dynamical states on the hysteretic response curve of the arch resonator with respect to the electrothermal actuation voltage. Set-and-reset operations of the memory states are performed by applying controlled dc pulses provided through the electrothermal actuation scheme, while the read-out operation is performed simultaneously by measuring the motional current through a capacitive detection technique. This novel memory device has the advantages of operating at low voltages and under room temperature. [2016-0043
Full Text Available In this study, we focus our investigation on task-specific cognitive modulation of early cortical auditory processing in human cerebral cortex. During the experiments, we acquired whole-head magnetoencephalography (MEG data while participants were performing an auditory delayed-match-to-sample (DMS task and associated control tasks. Using a spatial filtering beamformer technique to simultaneously estimate multiple source activities inside the human brain, we observed a significant DMS-specific suppression of the auditory evoked response to the second stimulus in a sound pair, with the center of the effect being located in the vicinity of the left auditory cortex. For the right auditory cortex, a non-invariant suppression effect was observed in both DMS and control tasks. Furthermore, analysis of coherence revealed a beta band (12 ~ 20 Hz DMS-specific enhanced functional interaction between the sources in left auditory cortex and those in left inferior frontal gyrus, which has been shown to involve in short-term memory processing during the delay period of DMS task. Our findings support the view that early evoked cortical responses to incoming acoustic stimuli can be modulated by task-specific cognitive functions by means of frontal-temporal functional interactions.
Evans, Theodore A.; Beran, Michael J.
Prospective memory (PM) involves forming intentions, retaining those intentions, and later executing those intended responses at the appropriate time. Few studies have investigated this capacity in animals. Monkeys performed a computerized task that assessed their ability to remember to make a particular response if they observed a PM cue embedded…
Ventura-León, José Luís; Caycho, Tomás
The purpose of the study is to determine the relationship between a group of writing tasks and the immediate auditory memory, as well as to establish differences according to sex and level of study. Two hundred and three schoolchildren of fifth and sixth grade of elementary education from Lima (Peru) participated; they were selected by a…
Koch, Iring; Rumiati, Raffaella I
Three dual-task experiments examined the influence of processing a briefly presented visual object for deferred verbal report on performance in an unrelated auditory-manual reaction time (RT) task. RT was increased at short stimulus-onset asynchronies (SOAs) relative to long SOAs, showing that memory consolidation processes can produce a functional processing bottleneck in dual-task performance. In addition, the experiments manipulated the spatial compatibility of the orientation of the visual object and the side of the speeded manual response. This cross-task compatibility produced relative RT benefits only when the instruction for the visual task emphasized overlap at the level of response codes across the task sets (Experiment 1). However, once the effective task set was in place, it continued to produce cross-task compatibility effects even in single-task situations ("ignore" trials in Experiment 2) and when instructions for the visual task did not explicitly require spatial coding of object orientation (Experiment 3). Taken together, the data suggest a considerable degree of task-set inertia in dual-task performance, which is also reinforced by finding costs of switching task sequences (e.g., AC --> BC vs. BC --> BC) in Experiment 3.
Wang, Shinmin; Gathercole, Susan E.
The current study investigated the cause of the reported problems in working memory in children with reading difficulties. Verbal and visuospatial simple and complex span tasks, and digit span and reaction times tasks performed singly and in combination, were administered to 46 children with single word reading difficulties and 45 typically…
James M Stone
Full Text Available Working memory is a key construct within cognitive science. It is an important theory in its own right, but the influence of working memory is enriched due to the widespread evidence that measures of its capacity are linked to a variety of functions in wider cognition. To facilitate the active research environment into this topic, we describe seven computer-based tasks that provide estimates of short-term and working memory incorporating both visuospatial and verbal material. The memory span tasks provided are; digit span, matrix span, arrow span, reading span, operation span, rotation span, and symmetry span. These tasks are built to be simple to use, flexible to adapt to the specific needs of the research design, and are open source. All files can be downloaded from the project website http://www.cognitivetools.uk and the source code is available via Github.
Ferré, Pilar; Fraga, Isabel; Comesaña, Montserrat; Sánchez-Casas, Rosa
Emotional stimuli have been repeatedly demonstrated to be better remembered than neutral ones. The aim of the present study was to test whether this advantage in memory is mainly produced by the affective content of the stimuli or it can be rather accounted for by factors such as semantic relatedness or type of encoding task. The valence of the stimuli (positive, negative and neutral words that could be either semantically related or unrelated) as well as the type of encoding task (focused on either familiarity or emotionality) was manipulated. The results revealed an advantage in memory for emotional words (either positive or negative) regardless of semantic relatedness. Importantly, this advantage was modulated by the encoding task, as it was reliable only in the task which focused on emotionality. These findings suggest that congruity with the dimension attended at encoding might contribute to the superiority in memory for emotional words, thus offering us a more complex picture of the underlying mechanisms behind the advantage for emotional information in memory.
Cox, R.; Hofman, W.F.; de Boer, M.; Talamini, L.M.
Sleep spindles have been connected to memory processes in various ways. In addition, spindles appear to be modulated at the local cortical network level. We investigated whether cueing specific memories during sleep leads to localized spindle modulations in humans. During learning of word-location
Kaczorowski, Catherine C.; Disterhoft, John F.
Normal aging disrupts hippocampal neuroplasticity and learning and memory. Aging deficits were exposed in a subset (30%) of middle-aged mice that performed below criterion on a hippocampal-dependent contextual fear conditioning task. Basal neuronal excitability was comparable in middle-aged and young mice, but learning-related modulation of the…
Engelhard, I.M.; Krypotos, A.M.; Leer, A.; van Dis, E.A.M.
This experiment tested whether dual-tasking (i.e., recalling the emotional memory while performing a visuospatial dual-task) neutralizes emotional memory, thereby decreasing conditioned responses. Undergraduates completed a differential conditioning paradigm with pictures of food items as
Kristjánsson, Arni; Campana, Gianluca
What we have recently seen and attended to strongly influences how we subsequently allocate visual attention. A clear example is how repeated presentation of an object's features or location in visual search tasks facilitates subsequent detection or identification of that item, a phenomenon known as priming. Here, we review a large body of results from priming studies that suggest that a short-term implicit memory system guides our attention to recently viewed items. The nature of this memory system and the processing level at which visual priming occurs are still debated. Priming might be due to activity modulations of low-level areas coding simple stimulus characteristics or to higher level episodic memory representations of whole objects or visual scenes. Indeed, recent evidence indicates that only minor changes to the stimuli used in priming studies may alter the processing level at which priming occurs. We also review recent behavioral, neuropsychological, and neurophysiological evidence that indicates that the priming patterns are reflected in activity modulations at multiple sites along the visual pathways. We furthermore suggest that studies of priming in visual search may potentially shed important light on the nature of cortical visual representations. Our conclusion is that priming occurs at many different levels of the perceptual hierarchy, reflecting activity modulations ranging from lower to higher levels, depending on the stimulus, task, and context-in fact, the neural loci that are involved in the analysis of the stimuli for which priming effects are seen.
Kevin T. Jones
Full Text Available The nature of parietal contributions to working memory (WM remain poorly understood but of considerable interest. We previously reported that posterior parietal damage selectively impaired WM probed by recognition (Berryhill & Olson, 2008a. Recent studies provided support using a neuromodulatory technique, transcranial direct current stimulation (tDCS applied to the right parietal cortex (P4. These studies confirmed parietal involvement in WM because parietal tDCS altered WM performance: anodal current tDCS improved performance in a change detection task, and cathodal current tDCS impaired performance on a sequential presentation task. In Experiment 1, we applied cathodal and anodal tDCS to the right parietal cortex and tested participants on both previously used WM tasks. When the WM task was difficult, parietal stimulation (anodal or cathodal improved WM performance selectively in participants with high WM capacity. In the low WM capacity group, parietal stimulation (anodal or cathodal impaired WM performance. These nearly equal and opposite effects were only observed when the WM task was challenging, as in the change detection task. Experiment 2 probed the interplay of WM task difficulty and WM capacity in a parametric manner by varying set size in the WM change detection task. Here, the effect of parietal stimulation (anodal or cathodal on the high WM capacity group followed a linear function as WM task difficulty increased with set size. These findings provide evidence that parietal involvement in WM performance depends on both WM capacity and WM task demands. We discuss these findings in terms of alternative WM strategies employed by low and high WM capacity individuals. We speculate that low WM capacity individuals do not recruit the posterior parietal lobe for WM tasks as efficiently as high WM capacity individuals. Consequently, tDCS provides greater benefit to individuals with high WM capacity.
Oi, Yuhei; Kita, Yosuke; Suzuki, Kota; Okumura, Yasuko; Okuzumi, Hideyuki; Shinoda, Haruo; Inagaki, Masumi
Spatial working memory (SWM) involves both simultaneous and sequential encoding, but the differences in their neural correlates are unclear. We investigated the differences in prefrontal cortex activity related to these SWM encoding types. We also examined the patterns of brain activity influencing individual visuospatial abilities (VSA). We conducted SWM tasks with two different conditions, sequential and simultaneous encoding, and examined hemodynamic activity in 39 healthy adults using near-infrared spectroscopy. The bilateral dorsolateral prefrontal cortex was activated more strongly in the sequential condition compared with the simultaneous condition. This suggests that prefrontal cortex activity underlying SWM is modulated by the type of encoding. We also found that individuals with high VSA showed weaker activation in the right-dorsolateral prefrontal cortex compared with those with lower VSA during the simultaneous condition. This hypoactivation is thought to reflect neural efficiency in the individuals with high ability. These findings are expected to lead to a better understanding of neural substrates for SWM.
Vogels, WWA; Dekker, MR; Brouwer, WH; de Jong, R
The primary purpose of the study was to identify event-based prospective-memory tasks that provide sensitive and reliable tools for assessing effects of normal aging in prospective-memory performance. Four prospective-memory tasks were selected from the literature or were newly developed, with the
Dipoppa, Mario; Gutkin, Boris S
Working memory (WM) requires selective information gating, active information maintenance, and rapid active updating. Hence performing a WM task needs rapid and controlled transitions between neural persistent activity and the resting state. We propose that changes in correlations in neural activity provides a mechanism for the required WM operations. As a proof of principle, we implement sustained activity and WM in recurrently coupled spiking networks with neurons receiving excitatory random background activity where background correlations are induced by a common noise source. We first characterize how the level of background correlations controls the stability of the persistent state. With sufficiently high correlations, the sustained state becomes practically unstable, so it cannot be initiated by a transient stimulus. We exploit this in WM models implementing the delay match to sample task by modulating flexibly in time the correlation level at different phases of the task. The modulation sets the network in different working regimes: more prompt to gate in a signal or clear the memory. We examine how the correlations affect the ability of the network to perform the task when distractors are present. We show that in a winner-take-all version of the model, where two populations cross-inhibit, correlations make the distractor blocking robust. In a version of the mode where no cross inhibition is present, we show that appropriate modulation of correlation levels is sufficient to also block the distractor access while leaving the relevant memory trace in tact. The findings presented in this manuscript can form the basis for a new paradigm about how correlations are flexibly controlled by the cortical circuits to execute WM operations.
Wang, Jian Hong; Liu, Xiao Fen; Chen, Yan Mei; Sun, Hua Yin; Fu, Yu; Ma, Man Xiu; He, Jing; Wang, Hai Yan; Wilson, Fraser A W; Carlson, Synnöve; Ma, Yuan Ye
Male and female heroin-dependent patients (HDPs) matched with "normal" people were tested on 4 topographical orientation tasks: schematic map-following, map-memory, schematic picture-following, and picture-memory tasks. The results showed that, in general, female HDPs demonstrated greater performance deficits in map-following and map-picture-memory tasks than did other participants. In the map-picture-following tasks, participants showed a preference for turning right versus turning left, reflected by lower correct scores and longer latencies in completing left-oriented tasks. In contrast, no difference in orientation preference was found for participants in memory tasks, except for female HDPs. Asymmetric dopamine receptor distribution in the brain, sex steroidal hormone, brain areas related to motor functioning and working memory, and gender-dependent lateralization may be involved in the different effects of heroin and rightward bias between men and women. ((c) 2007 APA, all rights reserved).
Full Text Available Performing two cognitively demanding tasks at the same time is known to decrease performance. The current study investigates the underlying executive functions of a dual-tasking situation involving the simultaneous performance of decision making under explicit risk and a working memory task. It is suggested that making a decision and performing a working memory task at the same time should particularly require monitoring - an executive control process supervising behavior and the state of processing on two tasks. To test the role of a supervisory/monitoring function in such a dual-tasking situation we investigated 122 participants with the Game of Dice Task plus 2-back task (GDT plus 2-back task. This dual task requires participants to make decisions under risk and to perform a 2-back working memory task at the same time. Furthermore, a task measuring a set of several executive functions gathered in the term concept formation (Modified Card Sorting Test, MCST and the newly developed Balanced Switching Task (BST, measuring monitoring in particular, were used. The results demonstrate that concept formation and monitoring are involved in the simultaneous performance of decision making under risk and a working memory task. In particular, the mediation analysis revealed that BST performance partially mediates the influence of MCST performance on the GDT plus 2-back task. These findings suggest that monitoring is one important subfunction for superior performance in a dual-tasking situation including decision making under risk and a working memory task.
Full Text Available Cannabinoid agonists generally have a disruptive effect on memory, learning, and operant behavior that is considered to be hippocampus-dependent. Nevertheless, under certain conditions, cannabinoid receptor activation may facilitate neuronal learning processes. For example, CB1 receptors are essential for the extinction of conditioned fear associations, indicating an important role for this receptor in neuronal emotional learning and memory. This review examines the diverse effects of cannabinoids on hippocampal memory and plasticity. It shows how the effects of cannabinoid receptor activation may vary depending on the route of administration, the nature of the task (aversive or not, and whether it involves emotional memory formation (e.g. conditioned fear and extinction learning or non-emotional memory formation (e.g. spatial learning. It also examines the memory stage under investigation (acquisition, consolidation, retrieval, extinction, and the brain areas involved. Differences between the effects of exogenous and endogenous agonists are also discussed. The apparently biphasic effects of cannabinoids on anxiety is noted as this implies that the effects of cannabinoid receptor agonists on hippocampal learning and memory may be attributable to a general modulation of anxiety or stress levels and not to memory per se. The review concludes that cannabinoids have diverse effects on hippocampal memory and plasticity that cannot be categorized simply into an impairing or an enhancing effect. A better understanding of the involvement of cannabinoids in memory processes will help determine whether the benefits of the clinical use of cannabinoids outweigh the risks of possible memory impairments.
Luis Augusto Teixeira
Full Text Available Daily life activities of humans are characterized by dual tasks, in which a manual task is performed concomitantly with a postural task. Based on the assumption that both manual and postural tasks require attentional resources, no consensus exists as to how the central nervous system modulates postural adjustments in dual tasks. The aim of the present study was to analyze the effect of a manual task requiring attentional resources on shoulder and ankle adjustments as a function of the direction and predictability of postural perturbation. The participants (n=6 were evaluated during the performance of a simple and a complex manual task, while the base of support was moved backward or forward. Latency of activation of the tibialis anterior and gastroc-nemius muscles and angular acceleration of the shoulder were analyzed. The results showed that execution of the complex manual task delayed postural adjustment. Moreover, this delay occurred differently depending on the direction of postural perturbation. The delay in postural adjustment occurred proximally in the case of anterior displacement of the platform, and distally in the case of posterior displacement. Postural adjustments were more affected by the attentional task than by the predictability of platform displacement. These results are consistent with the concept of an integrated control between manual actions and the maintenance of static posture.
Berger, Christoph; Erbe, Anna-Katharina; Ehlers, Inga; Marx, Ivo; Hauenstein, Karlheinz; Teipel, Stefan
Research suggests generally impaired cognitive control functions in working memory (WM) processes in amnestic mild cognitive impairment (MCI) and incipient Alzheimer's disease (AD). Little is known how emotional salience of task-irrelevant stimuli may modulate cognitive control of WM performance and neurofunctional activation in MCI and AD individuals. We investigated the impact of emotional task-irrelevant visual stimuli on cortical activation during verbal WM. Twelve AD/MCI individuals and 12 age-matched healthy individuals performed a verbal WM (nback-) task with task-irrelevant emotionally neutral and emotionally negative background pictures during fMRI measurement. AD/MCI individuals showed decreased WM performance compared with controls; both AD/MCI and control groups reacted slower during presentation of negative pictures, regardless of WM difficulty. The AD/MCI group showed increased activation in the left hemispheric prefrontal network, higher amygdala and less cerebellar activation with increasing WM task difficulty compared to healthy controls. Correlation analysis between neurofunctional activation and WM performance revealed a negative correlation between task sensitivity and activation in the dorsal anterior cingulum for the healthy controls but not for the AD/MCI group. Our data suggest compensatory activation in prefrontal cortex and amygdala, but also dysfunctional inhibition of distracting information in the AD/MCI group during higher WM task difficulty. Additionally, attentional processes affecting the correlation between WM performance and neurofunctional activation seem to be different between incipient AD and healthy aging.
Nguyen-Louie, Tam T.; Buckman, Jennifer F.; Ray, Suchismita
Background Alcohol cues can bias attention and elicit emotional reactions, especially in drinkers. Yet, little is known about how alcohol cues affect explicit and implicit memory processes, and how memory for alcohol cues is affected by acute alcohol intoxication. Methods Young adult participants (N=161) were randomly assigned to alcohol, placebo, or control beverage conditions. Following beverage consumption, they were shown neutral, emotional and alcohol-related pictures cues. Participants then completed free recall and repetition priming tasks to test explicit and implicit memory, respectively, for picture cues. Average blood alcohol concentration for the alcohol group was 74 ± 13 mg/dl when memory testing began. Two mixed linear model analyses were conducted to examine the effects of beverage condition, picture cue type, and their interaction on explicit and implicit memory. Results Picture cue type and beverage condition each significantly affected explicit recall of picture cues, whereas only picture cue type significantly influenced repetition priming. Individuals in the alcohol condition recalled significantly fewer pictures than those in other conditions, regardless of cue type. Both free recall and repetition priming were greater for emotional and alcohol-related cues compared to neutral picture cues. No interaction effects were detected. Conclusions Young adult drinkers showed enhanced explicit and implicit memory processing of alcohol cues compared to emotionally neutral cues. This enhanced processing for alcohol cues was on par with that seen for positive emotional cues. Acute alcohol intoxication did not alter this preferential memory processing for alcohol cues over neutral cues. PMID:26811126
Nguyen-Louie, Tam T; Buckman, Jennifer F; Ray, Suchismita; Bates, Marsha E
Alcohol cues can bias attention and elicit emotional reactions, especially in drinkers. Yet, little is known about how alcohol cues affect explicit and implicit memory processes, and how memory for alcohol cues is affected by acute alcohol intoxication. Young adult participants (N=161) were randomly assigned to alcohol, placebo, or control beverage conditions. Following beverage consumption, they were shown neutral, emotional and alcohol-related pictures cues. Participants then completed free recall and repetition priming tasks to test explicit and implicit memory, respectively, for picture cues. Average blood alcohol concentration for the alcohol group was 74±13mg/dl when memory testing began. Two mixed linear model analyses were conducted to examine the effects of beverage condition, picture cue type, and their interaction on explicit and implicit memory. Picture cue type and beverage condition each significantly affected explicit recall of picture cues, whereas only picture cue type significantly influenced repetition priming. Individuals in the alcohol condition recalled significantly fewer pictures than those in other conditions, regardless of cue type. Both free recall and repetition priming were greater for emotional and alcohol-related cues compared to neutral picture cues. No interaction effects were detected. Young adult drinkers showed enhanced explicit and implicit memory processing of alcohol cues compared to emotionally neutral cues. This enhanced processing for alcohol cues was on par with that seen for positive emotional cues. Acute alcohol intoxication did not alter this preferential memory processing for alcohol cues over neutral cues. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Sebastian, Catherine L; McCrory, Eamon J; De Brito, Stephane A; Viding, Essi
It has been shown that as cognitive demands of a non-emotional task increase, amygdala response to task-irrelevant emotional stimuli is reduced. However, it remains unclear whether effects are due to altered task demands, or altered perceptual input associated with task demands. Here, we present fMRI data from 20 adult males during a novel cognitive conflict task in which the requirement to scan emotional information was necessary for task performance and held constant across levels of cognitive conflict. Response to fearful facial expressions was attenuated under high (vs low) conflict conditions, as indexed by both slower reaction times and reduced right amygdala response. Psychophysiological interaction analysis showed that increased amygdala response to fear in the low conflict condition was accompanied by increased functional coupling with middle frontal gyrus, a prefrontal region previously associated with emotion regulation during cognitive task performance. These data suggest that amygdala response to emotion is modulated as a function of task demands, even when perceptual inputs are closely matched across load conditions. PPI data also show that, in particular emotional contexts, increased functional coupling of amygdala with prefrontal cortex can paradoxically occur when executive demands are lower. © The Author (2017). Published by Oxford University Press.
Piccoli, Tommaso; Valente, Giancarlo; Linden, David E J; Re, Marta; Esposito, Fabrizio; Sack, Alexander T; Di Salle, Francesco
The default mode network and the working memory network are known to be anti-correlated during sustained cognitive processing, in a load-dependent manner. We hypothesized that functional connectivity among nodes of the two networks could be dynamically modulated by task phases across time. To address the dynamic links between default mode network and the working memory network, we used a delayed visuo-spatial working memory paradigm, which allowed us to separate three different phases of working memory (encoding, maintenance, and retrieval), and analyzed the functional connectivity during each phase within and between the default mode network and the working memory network networks. We found that the two networks are anti-correlated only during the maintenance phase of working memory, i.e. when attention is focused on a memorized stimulus in the absence of external input. Conversely, during the encoding and retrieval phases, when the external stimulation is present, the default mode network is positively coupled with the working memory network, suggesting the existence of a dynamically switching of functional connectivity between "task-positive" and "task-negative" brain networks. Our results demonstrate that the well-established dichotomy of the human brain (anti-correlated networks during rest and balanced activation-deactivation during cognition) has a more nuanced organization than previously thought and engages in different patterns of correlation and anti-correlation during specific sub-phases of a cognitive task. This nuanced organization reinforces the hypothesis of a direct involvement of the default mode network in cognitive functions, as represented by a dynamic rather than static interaction with specific task-positive networks, such as the working memory network.
Geraci, Lisa; Hughes, Matthew L; Miller, Tyler M; De Forrest, Ross L
Negative aging stereotypes can lead older adults to perform poorly on memory tests. Yet, memory performance can be improved if older adults have a single successful experience on a cognitive test prior to participating in a memory experiment (Geraci & Miller, 2013, Psychology and Aging, 28, 340-345). The current study examined the effects of different types of prior task experience on subsequent memory performance. Before participating in a verbal free recall experiment, older adults in Experiment 1 successfully completed either a verbal or a visual cognitive task or no task. In Experiment 2, they successfully completed either a motor task or no task before participating in the free recall experiment. Results from Experiment 1 showed that relative to control (no prior task), participants who had prior success, either on a verbal or a visual task, had better subsequent recall performance. Experiment 2 showed that prior success on a motor task, however, did not lead to a later memory advantage relative to control. These findings demonstrate that older adults' memory can be improved by a successful prior task experience so long as that experience is in a cognitive domain.
Bryant, Richard A; Chan, Iris
Although priming mental representations of attachment security reduces arousal, research has not examined the effect of attachment on the retrieval of emotionally arousing memories. This study investigated the effect of priming attachment security on the retrieval of emotional memories. Seventy-five participants viewed negative and neutral images, and two days later received either an attachment prime or a control prime immediately prior to free recall of the images. Two days later, participants reported how frequently they experienced intrusions of the negative images. The attachment group had less distress, and reported fewer subsequent intrusions than the control group. Attachment style moderated these effects such that individuals with an avoidant attachment style were not impacted by the attachment prime. These findings suggest that priming attachment security decreases distress during memory reactivation, and this may reduce subsequent intrusive memories. Copyright © 2017 Elsevier Inc. All rights reserved.
Shah, Darshna S; Prados, Jose; Gamble, Jasmin; De Lillo, Carlo; Gibson, Claire L
The present study assessed the spatial abilities of male and female human participants using different versions of the non-navigational Corsi block-tapping test (CBT) and a search task. Males performed significantly better than females on the standard manual version of the CBT; however, the standard CBT does not allow discrimination between spatial memory span and the role of spatial organisational factors (structure, path length and presence of crossings) in the sequences to recall. These organisational factors were assessed, therefore, in an experiment in which 7-block-sequences had to be recalled in a computerised version of the CBT. No sex differences in performance were observed on the computerised CBT, indicating that males do not make better use of spatial organisational principles. Accordingly, sex differences observed in the manual CBT are likely to rely upon differences in memory span between males and females. In the search task, participants could locate a goal by reference to a Euclidian space (the geometry of a virtual enclose) or to proximal non-geometric cues. Both male and female participants showed a preference for the non-geometric cues, which overshadowed learning about the geometric cues when the two sets were available simultaneously during the training stage. These results indicate that sex differences do exist in those tests which are dependent on memory span. Sex differences were absent, however, in spatial organisational skills or in the usage of Euclidian and egocentric strategies to solve problems relying on spatial ability. Copyright © 2013 Elsevier B.V. All rights reserved.
Nijboer, Menno; Borst, Jelmer; van Rijn, Hedderik; Taatgen, Niels
Working memory can be a major source of interference in dual tasking. However, there is no consensus on whether this interference is the result of a single working memory bottleneck, or of interactions between different working memory components that together form a complete working-memory system.
Hafiz, Md Abdullah Al
We demonstrate reconfigurable logic and random access memory devices based on an axially modulated clamped-guided arch resonator. The device is electrostatically actuated and the motional signal is capacitively sensed, while the resonance frequency is modulated through an axial electrostatic force from the guided side of the microbeam. A multi-physics finite element model is used to verify the effectiveness of the axial modulation. We present two case studies: first, a reconfigurable two-input logic gate based on the linear resonance frequency modulation, and second, a memory element based on the hysteretic frequency response of the resonator working in the nonlinear regime. The energy consumptions of the device for both logic and memory operations are in the range of picojoules, promising for energy efficient alternative computing paradigm.
Tadmor, Avia; McNally, Richard J; Engelhard, Iris M
BACKGROUND AND OBJECTIVES: People who perform a cognitively demanding secondary task while recalling a distressing memory often experience the memory as less emotional, vivid, or accurate during subsequent recollections. In this experiment, we tested whether the emotional valence (positive versus
Caspar, Emilie A.; Gevers, Wim; Cleeremans, Axel
Here, we ask whether placebo-suggestion (without any form of hypnotic induction) can modulate the resolution of cognitive conflict. Naïve participants performed a Stroop Task while wearing an EEG cap described as a “brain wave” machine. In Experiment 1, participants were made to believe that the EEG cap would either enhance or decrease their color perception and performance on the Stroop task. In Experiment 2, participants were explicitly asked to imagine that their color perception and performance would be enhanced or decreased (non-hypnotic imaginative suggestion). We observed effects of placebo-suggestion on Stroop interference on accuracy: interference was decreased with positive suggestion and increased with negative suggestion compared to baseline. Intra-individual variability was also increased under negative suggestion compared to baseline. Compliance with the instruction to imagine a modulation of performance, on the other hand, did not influence accuracy and only had a negative impact on response latencies and on intra-individual variability, especially in the congruent condition of the Stroop Task. Taken together, these results demonstrate that expectations induced by a placebo-suggestion can modulate our ability to resolve cognitive conflict, either facilitating or impairing response accuracy depending on the suggestion’s contents. Our results also demonstrate a dissociation between placebo-suggestion and non-hypnotic imaginative suggestion. PMID:24130735
Bensoussan, Laurent; Duclos, Yann; Rossi-Durand, Christiane
This study aimed to determine whether the performance of a mental task affects motoneuron activity. To this end, the tonic discharge pattern of wrist extensor motor units was analyzed in healthy subjects while they were required to maintain a steady wrist extension force and to concurrently perform a mental arithmetic (MA) task. A shortening of the mean inter-spike interval (ISI) and a decrease in ISI variability occurred when MA task was superimposed to the motor task. Aloud and silent MA affected equally the rate and variability of motoneuron discharge. Increases in surface EMG activity and force level were consistent with the modulation of the motor unit discharge rate. Trial-by-trial analysis of the characteristics of motor unit firing revealed that performing MA increases activation of wrist extensor SMU. It is suggested that increase in muscle spindle afferent activity, resulting from fusimotor drive activation by MA, may have contributed to the increase in synaptic inputs to motoneurons during the mental task performance, likely together with enhancement in the descending drive. The finding that a mental task affects motoneuron activity could have consequences in assessment of motor disabilities and in rehabilitation in motor pathologies. Copyright © 2012 Elsevier B.V. All rights reserved.
Kim, Dong Hyun; Kim, Jong Min; Park, Se Jin; Lee, Seungheon; Shin, Chan Young; Cheong, Jae Hoon; Ryu, Jong Hoon
Available evidence strongly suggests that the γ-aminobutyric acid type A (GABAA) receptor has a crucial role in memory retrieval. However, the signaling mechanisms underlying the role of GABAA receptor modulation in memory retrieval are unclear. We conducted one-trial passive avoidance task with pre-retention trial drug administration in the hippocampus to test the effects of GABAA receptor modulation on memory retrieval. We further tested the co-involvement of signaling molecules: extracellu...
Guerra, Gustavo Petri; Rubin, Maribel Antonello; Mello, Carlos Fernando
Spermine and spermidine are natural polyamines that are produced mainly via decarboxylation of l-ornithine and the sequential transfer of aminopropyl groups from S-adenosylmethionine to putrescine by spermidine synthase and spermine synthase. Spermine and spermidine interact with intracellular and extracellular acidic residues of different nature, including nucleic acids, phospholipids, acidic proteins, carboxyl- and sulfate-containing polysaccharides. Therefore, multiple actions have been suggested for these polycations, including modulation of the activity of ionic channels, protein synthesis, protein kinases, and cell proliferation/death, within others. In this review we summarize these neurochemical/neurophysiological/morphological findings, particularly those that have been implicated in the improving and deleterious effects of spermine and spermidine on learning and memory of naïve animals in shock-motivated and nonshock-motivated tasks, from a historical perspective. The interaction with the opioid system, the facilitation and disruption of morphine-induced reward and the effect of polyamines and putative polyamine antagonists on animal models of cognitive diseases, such as Alzheimer's, Huntington, acute neuroinflammation and brain trauma are also reviewed and discussed. The increased production of polyamines in Alzheimer's disease and the biphasic nature of the effects of polyamines on memory and on the NMDA receptor are also considered. In light of the current literature on polyamines, which include the description of an inborn error of the metabolism characterized by mild-to moderate mental retardation and polyamine metabolism alterations in suicide completers, we can anticipate that polyamine targets may be important for the development of novel strategies and approaches for understanding the etiopathogenesis of important central disorders and their pharmacological treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Kliegel, Matthias; Mahy, Caitlin E V; Voigt, Babett; Henry, Julie D; Rendell, Peter G; Aberle, Ingo
This study presents evidence that 9- and 10-year-old children outperform 6- and 7-year-old children on a measure of event-based prospective memory and that retrieval-based factors systematically influence performance and age differences. All experiments revealed significant age effects in prospective memory even after controlling for ongoing task performance. In addition, the provision of a less absorbing ongoing task (Experiment 1), higher cue salience (Experiment 2), and cues appearing in the center of attention (Experiment 3) were each associated with better performance. Of particular developmental importance was an age by cue centrality (in or outside of the center of attention) interaction that emerged in Experiment 3. Thus, age effects were restricted to prospective memory cues appearing outside of the center of attention, suggesting that the development of prospective memory across early school years may be modulated by whether a cue requires overt monitoring beyond the immediate attentional context. Because whether a cue is in or outside of the center of attention might determine the amount of executive control needed in a prospective memory task, findings suggest that developing executive control resources may drive prospective memory development across primary school age. Copyright © 2013 Elsevier Inc. All rights reserved.
Full Text Available Variability of neural discharges can be revealing about the computations and network properties of neuronal populations during the performance of cognitive tasks. We sought to quantify neuronal variability in the prefrontal cortex of naïve monkeys that were only required to fixate, and to examine how this measure was altered by learning and execution of a working memory task. We therefore performed analysis of a large database of recordings in the same animals, using the same stimuli, before and after training. Our results indicate that the Fano Factor, a measure of variability, differs across neurons depending on their functional properties both before and after learning. Fano Factor generally decreased after learning the task. Variability was modulated by task events and displayed lowest values during the stimulus presentation. Nonetheless, the decrease in variability after training was present even prior to the presentation of any stimuli, in the fixation period. The greatest decreases were observed comparing populations of neurons that exhibited elevated firing rate during the trial events. Our results offer insights on how properties of the prefrontal network are affected by performance of a cognitive task.
Qi, Xue-Lian; Constantinidis, Christos
Variability of neural discharges can be revealing about the computations and network properties of neuronal populations during the performance of cognitive tasks. We sought to quantify neuronal variability in the prefrontal cortex of naïve monkeys that were only required to fixate, and to examine how this measure was altered by learning and execution of a working memory task. We therefore performed analysis of a large database of recordings in the same animals, using the same stimuli, before and after training. Our results indicate that the Fano Factor, a measure of variability, differs across neurons depending on their functional properties both before and after learning. Fano Factor generally decreased after learning the task. Variability was modulated by task events and displayed lowest values during the stimulus presentation. Nonetheless, the decrease in variability after training was present even prior to the presentation of any stimuli, in the fixation period. The greatest decreases were observed comparing populations of neurons that exhibited elevated firing rate during the trial events. Our results offer insights on how properties of the prefrontal network are affected by performance of a cognitive task.
Osaka, Mariko; Yaoi, Ken; Minamoto, Takehiro; Osaka, Naoyuki
The present study investigated when emotion modulates working memory from the perspective of neural activation. Using fMRI, we measured brain activity during the encoding and retrieval phases of a reading span test (RST) that used emotional contexts. The emotional RST required participants to read sentences that elicited negative, neural or positive emotional states while they were memorizing target words from the sentences. Compared with the neutral RST, the negative RST activated the right amygdala during the reading phase. Significant activation was also found in the parahippocampal gyrus, albeit only after activation of the amygdala became comparable to that in the neutral RST. In contrast, the positive RST activated the substantia nigra during the reading phase relative to the neutral RST. These findings suggest that negative and positive emotions modulate working memory through distinctive neural circuits. We also discuss possible relationships between emotional modulation and working memory capacity. PMID:23459220
Osaka, Mariko; Yaoi, Ken; Minamoto, Takehiro; Osaka, Naoyuki
The present study investigated when emotion modulates working memory from the perspective of neural activation. Using fMRI, we measured brain activity during the encoding and retrieval phases of a reading span test (RST) that used emotional contexts. The emotional RST required participants to read sentences that elicited negative, neural or positive emotional states while they were memorizing target words from the sentences. Compared with the neutral RST, the negative RST activated the right amygdala during the reading phase. Significant activation was also found in the parahippocampal gyrus, albeit only after activation of the amygdala became comparable to that in the neutral RST. In contrast, the positive RST activated the substantia nigra during the reading phase relative to the neutral RST. These findings suggest that negative and positive emotions modulate working memory through distinctive neural circuits. We also discuss possible relationships between emotional modulation and working memory capacity.
van der Meer, Dennis; Hoekstra, Pieter J; van Rooij, Daan; Winkler, Anderson M; van Ewijk, Hanneke; Heslenfeld, Dirk J; Oosterlaan, Jaap; Faraone, Stephen V; Franke, Barbara; Buitelaar, Jan K; Hartman, Catharina A
Individuals with attention-deficit/hyperactivity disorder (ADHD) often have heightened levels of anxiety, which has been associated with worse performance on working memory tasks. Knowledge of the neural pathways underlying the combined presence of ADHD and anxiety may aid in a better understanding of their co-occurrence. Therefore, we investigated how anxiety modulates the effect of ADHD severity on neural activity during a visuospatial working memory (VSWM) task. Neuroimaging data were available for 371 adolescents and young adults participating in the multicentre cohort study NeuroIMAGE (average age 17.1 years). We analysed the effects of ADHD severity, anxiety severity and their interaction on-task accuracy, and on neural activity associated with working memory (VSWM trials minus baseline), and memory load (high memory load trials minus low load trials). Anxiety significantly modulated the relation between ADHD severity and neural activity in the cerebellum for the working memory contrast, and bilaterally in the striatum and thalamus for the memory load contrast. We found that ADHD with co-occurring anxiety is associated with lowered neural activity during a VSWM task in regions important for information gating. This fits well with previous theorising on ADHD with co-occurring anxiety, and illustrates the neurobiological heterogeneity of ADHD.
Smith, Rebekah E; McConnell Rogers, Melissa D; McVay, Jennifer C; Lopez, Joshua A; Loft, Shayne
Implementation intentions are a self-regulatory strategy broadly studied in the area of social cognition that can improve realization of one's goals and improve performance on prospective memory tasks. Three experiments, using a non-focal task for which the prospective memory targets were specified at the time of intention formation, investigated whether (and how) implementation intentions can improve non-focal prospective memory performance. An improvement in prospective memory performance was accompanied by an increase in the allocation of conscious resources to the prospective memory task, but not by an increase in perceived importance of the prospective memory task. The third experiment also investigated the effects of implementation intentions on recall of the appropriate action and found that accurate action recall was improved by implementation intentions. Finally, the effect of implementation intention instructions on cognitive processes that underlie non-focal prospective memory performance was investigated using a multinomial model. Copyright © 2014 Elsevier Inc. All rights reserved.
LaLumiere, Ryan T; McGaugh, James L; McIntyre, Christa K
Memory consolidation involves the process by which newly acquired information becomes stored in a long-lasting fashion. Evidence acquired over the past several decades, especially from studies using post-training drug administration, indicates that emotional arousal during the consolidation period influences and enhances the strength of the memory and that multiple different chemical signaling systems participate in this process. The mechanisms underlying the emotional influences on memory involve the release of stress hormones and activation of the basolateral amygdala, which work together to modulate memory consolidation. Moreover, work suggests that this amygdala-based memory modulation occurs with numerous types of learning and involves interactions with many different brain regions to alter consolidation. Additionally, studies suggest that emotional arousal and amygdala activity in particular influence synaptic plasticity and associated proteins in downstream brain regions. This review considers the historical understanding for memory modulation and cellular consolidation processes and examines several research areas currently using this foundational knowledge to develop therapeutic treatments. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.
Morey, Candice C; Mall, Jonathan T
Some evidence suggests that memory for serial order is domain-general. Evidence also points to asymmetries in interference between verbal and visual-spatial tasks. We confirm that concurrently remembering verbal and spatial serial lists provokes substantial interference compared with remembering a single list, but we further investigate the impact of this interference throughout the serial position curve, where asymmetries are indeed apparent. A concurrent verbal order memory task affects spatial memory performance throughout the serial positions of the list, but performing a spatial order task affects memory for the verbal serial list only for early list items; in the verbal task only, the final items are unaffected by a concurrent task. Adding suffixes eliminates this asymmetry, resulting in impairment throughout the list for both tasks. These results suggest that domain-general working memory resources may be supplemented with resources specific to the verbal domain, but perhaps not with equivalent spatial resources.
Riggs, Lily; McQuiggan, Douglas A; Farb, Norman; Anderson, Adam K; Ryan, Jennifer D
The presence of emotional stimuli results in a central/peripheral tradeoff effect in memory: memory for central details is enhanced at the cost of peripheral items. It has been assumed that emotion-modulated differences in memory are the result of differences in attention, but this has not been tested directly. The present experiment used eye movement monitoring as an index of overt attention allocation and mediation analysis to determine whether differences in attention were related to subsequent memory. Participants viewed negative and neutral scenes surrounded by three neutral objects and were then given a recognition memory test. The results revealed evidence in support of a central/peripheral tradeoff in both attention and memory. However, contrary with previous assumptions, whereas attention partially mediated emotion-enhanced memory for central pictures, it did not explain the entire relationship. Further, although centrally presented emotional stimuli led to decreased number of eye fixations toward the periphery, these differences in viewing did not contribute to emotion-impaired memory for specific details pertaining to the periphery. These findings suggest that the differential influence of negative emotion on central versus peripheral memory may result from other cognitive influences in addition to overt visual attention or on postencoding processes. 2011 APA, all rights reserved
Full Text Available The subjective experience of cognitive dysfunction (“fibrofog” is common in fibromyalgia. This study investigated the relation between subjective appraisal of cognitive function, objective cognitive task performance, and brain activity during a cognitive task using functional magnetic resonance imaging (fMRI. Sixteen fibromyalgia patients and 13 healthy pain-free controls completed a battery of questionnaires, including the Multiple Ability Self-Report Questionnaire (MASQ, a measure of self-perceived cognitive difficulties. Participants were evaluated for working memory performance using a modified N-back working memory task while undergoing Blood Oxygen Level Dependent (BOLD fMRI measurements. Fibromyalgia patients and controls did not differ in working memory performance. Subjective appraisal of cognitive function was associated with better performance (accuracy on the working memory task in healthy controls but not in fibromyalgia patients. In fibromyalgia patients, increased perceived cognitive difficulty was positively correlated with the severity of their symptoms. BOLD response during the working memory task did not differ between the groups. BOLD response correlated with task accuracy in control subjects but not in fibromyalgia patients. Increased subjective cognitive impairment correlated with decreased BOLD response in both groups but in different anatomic regions. In conclusion, “fibrofog” appears to be better characterized by subjective rather than objective impairment. Neurologic correlates of this subjective experience of impairment might be separate from those involved in the performance of cognitive tasks.
Haam, Juhee; Yakel, Jerrel L
Acetylcholine (ACh) plays an important role in memory function and has been implicated in aging-related dementia, in which the impairment of hippocampus-dependent learning strongly manifests. Cholinergic neurons densely innervate the hippocampus, mediating the formation of episodic as well as semantic memory. Here, we will review recent findings on acetylcholine's modulation of memory function, with a particular focus on hippocampus-dependent learning, and the circuits involved. In addition, we will discuss the complexity of ACh actions in memory function to better understand the physiological role of ACh in memory. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms. © 2017 International Society for Neurochemistry.
Rummel, Jan; Smeekens, Bridget A.; Kane, Michael J.
Prospective memory (PM) is the cognitive ability to remember to fulfill intended action plans at the appropriate future moment. Current theories assume that PM fulfillment draws on attentional processes. Accordingly, pending PM intentions interfere with other ongoing tasks to the extent to which both tasks rely on the same processes. How do people…
Rossion, B; Campanella, S; Gomez, C M; Delinte, A; Debatisse, D; Liard, L; Dubois, S; Bruyer, R; Crommelinck, M; Guerit, J M
In order to investigate stimulus-related and task-related electrophysiological activity relevant for face processing, event-related potentials (ERPs) from 58 electrodes at standard EEG sites were recorded while subjects performed a simple visual discrimination (control) task, in addition to various face processing tasks: recognition of previously learned faces and gender decision on familiar and unfamiliar faces. Three electrophysiological components or dipolar complex were recorded in all subjects: an occipital early component (P1, around 110 ms); a vertex positive potential (VPP; around 158 ms) which appeared to be specific to faces; and a negative central component, N2 (around 230 ms). Parametric analysis and source localization were applied to these components by means of a single-subject analysis methodology. No effect of familiarity was observed on any of these early component. While the VPP appears to be independent of the kind of processing performed, face task modulations of the early P1 and the N2 were observed, with a higher amplitude for the recognition than for the gender discrimination task. An attentional modulation of early visual areas is proposed for the first effect (P1 modulation), while the N2 seems to be related to general visual memory processing. This study strongly suggests that the VPP reflects an early visual stage of face processing in the fusiform gyrus that is strictly stimulus-related and independent of familiarity. It also shows that source localization algorithms may give reliable solutions on single subject averages for early visual components despite high inter-subject variability of the surface characteristics of ERPs.
Full Text Available We have previously shown that temporal prediction errors (PEs, the differences between the expected and the actual stimulus’ onset times modulate the effective connectivity between the anterior cingulate cortex and the right anterior insular cortex (rAI, causing the activity of the rAI to decrease. The activity of the rAI is associated with efficient performance under uncertainty (e.g., changing a prepared behavior when a change demand is not expected, which leads to hypothesize that temporal PEs might disrupt behavior-change performance under uncertainty. This hypothesis has not been tested at a behavioral level. In this work, we evaluated this hypothesis within the context of task switching and concurrent temporal predictions. Our participants performed temporal predictions while observing one moving ball striking a stationary ball which bounced off with a variable temporal gap. Simultaneously, they performed a simple color comparison task. In some trials, a change signal made the participants change their behaviors. Performance accuracy decreased as a function of both the temporal PE and the delay. Explaining these results without appealing to ad-hoc concepts such as executive control is a challenge for cognitive neuroscience. We provide a predictive coding explanation. We hypothesize that exteroceptive and proprioceptive minimization of PEs would converge in a fronto-basal ganglia network which would include the rAI. Both temporal gaps (or uncertainty and temporal PEs would drive and modulate this network respectively. Whereas the temporal gaps would drive the activity of the rAI, the temporal PEs would modulate the endogenous excitatory connections of the fronto-striatal network. We conclude that in the context of perceptual uncertainty, the system is not able to minimize perceptual PE, causing the ongoing behavior to finalize and, in consequence, disrupting task switching.
Full Text Available Many cognitive abilities decline with aging, making it difficult to detect pathological changes against a background of natural changes in cognition. Most of the tests to assess cognitive decline are artificial tasks that have little resemblance to the problems faced by people in everyday life. This means both that people may have little practice doing such tasks (potentially contributing to the decline in performance and that the tasks may not be good predictors of real-world cognitive problems.In this study, we test the performance of young people (18-25 years and older people (60+-year-olds on a novel, more ecologically valid test of episodic memory: the real-world What-Where-When (WWW memory test. We also compare them on a battery of other cognitive tests, including working memory, psychomotor speed, executive function, and episodic memory. Older people show the expected age-related declines on the test battery. In the WWW memory task, older people were more likely to fail to remember any What-Where-When combination than younger people were, although they did not significantly differ in their overall WWW score due to some older people performing as well as or better than most younger people. WWW memory performance was significantly predicted by other measures of episodic memory, such as the single-trial learning and long-term retention in the Rey Auditory Verbal Learning task and Combined Object Location Memory in the Object Relocation task. Self-reported memory complaints also predicted performance on the WWW task.These findings confirm that our real-world WWW memory task is a valid measure of episodic memory, with high ecological validity, which may be useful as a predictor of everyday memory abilities. The task will require a bit more development to improve its sensitivity to cognitive declines in aging and to potentially distinguish between mentally healthy older adults and those with early signs of cognitive pathologies.
Watanabe, Tatsunori; Koyama, Soichiro; Tanabe, Shigeo; Nojima, Ippei
When multiple sensory modalities are simultaneously presented, reaction time can be reduced while interference enlarges. The purpose of this research was to examine the effects of task-irrelevant acoustic accessory stimuli simultaneously presented with visual imperative stimuli on executive function during stepping. Executive functions were assessed by analyzing temporal events and errors in the initial weight transfer of the postural responses prior to a step (anticipatory postural adjustment errors). Eleven healthy young adults stepped forward in response to a visual stimulus. We applied a choice reaction time task and the Simon task, which consisted of congruent and incongruent conditions. Accessory stimuli were randomly presented with the visual stimuli. Compared with trials without accessory stimuli, the anticipatory postural adjustment error rates were higher in trials with accessory stimuli in the incongruent condition and the reaction times were shorter in trials with accessory stimuli in all the task conditions. Analyses after division of trials according to whether anticipatory postural adjustment error occurred or not revealed that the reaction times of trials with anticipatory postural adjustment errors were reduced more than those of trials without anticipatory postural adjustment errors in the incongruent condition. These results suggest that accessory stimuli modulate the initial motor programming of stepping by lowering decision threshold and exclusively under spatial incompatibility facilitate automatic response activation. The present findings advance the knowledge of intersensory judgment processes during stepping and may aid in the development of intervention and evaluation tools for individuals at risk of falls. Copyright © 2015 the American Physiological Society.
Abush, Hila; Akirav, Irit
Considerable evidence demonstrates that cannabinoid agonists impair whereas cannabinoid antagonists improve memory and plasticity. However, recent studies suggest that the effects of cannabinoids on learning do not necessarily follow these simple patterns, particularly when emotional memory processes are involved. We investigated the involvement of the cannabinoid system in hippocampal learning and plasticity using the fear-related inhibitory avoidance (IA) and the non-fear-related spatial learning paradigms, and cellular models of learning and memory, i.e., long-term potentiation (LTP) and long-term depression (LTD). We found that microinjection into the CA1 of the CB1/CB2 receptor agonist WIN55,212-2 (5 μg/side) and an inhibitor of endocannabinoid reuptake and breakdown AM404 (200 ng/side) facilitated the extinction of IA, while the CB1 receptor antagonist AM251 (6 ng/side) impaired it. WIN55,212-2 and AM251 did not affect IA conditioning, while AM404 enhanced it, probably due to a drug-induced increase in pain sensitivity. However, in the water maze, systemic or local CA1 injections of AM251, WIN55,212-2, and AM404 all impaired spatial learning. We also found that i.p. administration of WIN55,212-2 (0.5 mg/kg), AM404 (10 mg/kg), and AM251 (2 mg/kg) impaired LTP in the Schaffer collateral-CA1 projection, whereas AM404 facilitated LTD. Our findings suggest diverse effects of the cannabinoid system on CA1 memory and plasticity that cannot be categorized simply into an impairing or an enhancing effect of cannabinoid activation and deactivation, respectively. Moreover, they provide preclinical support for the suggestion that targeting the endocannabinoid system may aid in the treatment of disorders associated with impaired extinction-like processes, such as post-traumatic stress disorder. © 2009 Wiley-Liss, Inc.
Blinowska, Katarzyna J; Kamiński, Maciej; Brzezicka, Aneta; Kamiński, Jan
The dynamic pattern of functional connectivity during a working memory task was investigated by means of the short-time directed transfer function. A clear-cut picture of transmissions was observed with the main centres of propagation located in the frontal and parietal regions, in agreement with imaging studies and neurophysiological hypotheses concerning the mechanisms of working memory. The study of the time evolution revealed that most of the time short-range interactions prevailed, whereas the communication between the main centres of activity occurred more sparsely and changed dynamically in time. The patterns of connectivity were quantified by means of a network formalism based on assortative mixing--an approach novel in the field of brain networks study. By means of application of the above method, we have demonstrated the existence of a modular structure of brain networks. The strength of interaction inside the modules was higher than between modules. The obtained results are compatible with theories concerning metabolic energy saving and efficient wiring in the brain, which showed that preferred organization includes modular structure with dense connectivity inside the modules and more sparse connections between the modules. The presented detailed temporal and spatial patterns of propagation are in line with the neurophysiological hypotheses concerning the role of gamma and theta activity in information processing during a working memory task.
Wittig, John H., Jr.; Richmond, Barry J.
Seven monkeys performed variants of two short-term memory tasks that others have used to differentiate between selective and nonselective memory mechanisms. The first task was to view a list of sequentially presented images and identify whether a test matched any image from the list, but not a distractor from a preceding list. Performance was best…
Carr, Joshua K.; Fournier, Neil M.; Lehmann, Hugo
We examined whether increasing retrieval difficulty in a spatial memory task would promote the recruitment of the anterior cingulate cortex (ACC) similar to what is typically observed during remote memory retrieval. Rats were trained on the hidden platform version of the Morris Water Task and tested three or 30 d later. Retrieval difficulty was…
van der Kooij, Michael A; Sandi, Carmen
Intact social memory forms the basis of meaningful interactions between individuals. Many factors can modulate the quality of social memory, and these have been studied in detail in rodents. Social memory, however, cannot be considered a single entity. The term social memory reflects different processes, such as social recognition of a novel conspecific individual and social learning (or 'learning from others'). This review summarizes the findings obtained with behavioral paradigms that were developed for the study of memory formation by social recognition and social learning. In particular, we focus on studies that include tests for social habituation/discrimination paradigms, tests for memory of a previously established social hierarchy and the social transmission of the food preference test. The role of individual differences and the main neurobiological mechanisms (i.e., the brain regions and neurochemical systems involved) that have been implicated in each of these types of social-related memories are reviewed. In addition, we address the key modulatory influence of stress on the formation of these types of memories; discussing the contribution of central (corticotropin-releasing factor, CRF) and peripheral (glucocorticoids) stress systems and their interactions with the social neuropeptide systems. Overall, we present here a general overview of the current state of a thriving research area within the field of social neuroscience. Copyright © 2011 Elsevier Ltd. All rights reserved.
Visual working memory (VWM) is an online memory buffer that is typically assumed to be immune to source memory confusions. Accordingly, the few studies that have investigated the role of proactive interference (PI) in VWM tasks found only a modest PI effect at best. In contrast, a recent study has found a substantial PI effect in that performance…
ANA M DONOSO
Full Text Available Working memory (WM designates the retention of objects or events in conscious awareness when these are not present in the environment. Many studies have focused on the interference properties of distracter stimuli in working memory, but these studies have mainly examined the influence of the intensity of these stimuli. Little is known about the memory modulation of hedonic content of distracter stimuli as they also may affect WM performance or attentional tasks. In this paper, we have studied the performance of a visual WM task where subjects recollect from five to eight visually presented objects while they are simultaneously exposed to additional - albeit weak- auditory or olfactory distracter stimulus. We found that WM performance decreases as the number of Ítems to remember increases, but this performance was unaltered by any of the distracter stimuli. However, when performance was correlated to the subject's perceived hedonic valúes, distracter stimuli classified as negative exhibit higher error rates than positive, neutral or control stimuli. We demónstrate that some hedonic content of otherwise neutral stimuli can strongly modulate memory processes.
Lima, Ramon H.; Radiske, Andressa; Kohler, Cristiano A.; Gonzalez, Maria Carolina; Bevilaqua, Lia R.; Rossato, Janine I.; Medina, Jorge H.; Cammarota, Martin
Late post-training activation of the ventral tegmental area (VTA)-hippocampus dopaminergic loop controls the entry of information into long-term memory (LTM). Nicotinic acetylcholine receptors (nAChR) modulate VTA function, but their involvement in LTM storage is unknown. Using pharmacological and behavioral tools, we found that…
Arning, Larissa; Stock, Ann-Kathrin; Kloster, Eugen; Epplen, Jörg T; Beste, Christian
Sensory memory systems are modality-specific buffers that comprise information about external stimuli, which represent the earliest stage of information processing. While these systems have been the subject of cognitive neuroscience research for decades, little is known about the neurobiological basis of sensory memory. However, accumulating evidence suggests that the glutamatergic system and systems influencing glutamatergic neural transmission are important. In the current study we examine if functional promoter variations in neuropeptide Y (NPY) and its receptor gene NPY2R affect iconic memory processes using a partial report paradigm. We found that iconic memory decayed much faster in individuals carrying the rare promoter NPY2R G allele which is associated with increased expression of the Y2 receptor. Possibly this effect is due to altered presynaptic inhibition of glutamate release, known to be modulated by Y2 receptors. Altogether, our results provide evidence that the functionally relevant single nucleotide polymorphism (SNP) in the NPY2R promoter gene affect circumscribed processes of early sensory processing, i.e. only the stability of information in sensory memory buffers. This leads us to suggest that especially the stability of information in sensory memory buffers depends on glutamatergic neural transmission and factors modulating glutamatergic turnover. Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.
Kyria Finardi; Gicele Vergine Vieira Prebianca
This is an experimental study which aimed at investigating theralationsship between working memory capacity and measuresof L2 speech performance in a picture description task. The mainassumption underlying the present study was that L2 speaking isa complex cognitive task which is carried out within theconstraints of a limited-capacity system, namely, working memory.In this system, there are trade-off effects between the storage andprocessing functions of working memory just as in L2 speakingt...
Reboreda, Antonio; Theissen, Frederik M; Valero-Aracama, Maria; Arboit, Alberto; Corbu, Mihaela A; Yoshida, Motoharu
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. Published by Elsevier B.V.
Salvetti, Beatrice; Morris, Richard G. M.; Wang, Szu-Han
Many insignificant events in our daily life are forgotten quickly but can be remembered for longer when other memory-modulating events occur before or after them. This phenomenon has been investigated in animal models in a protocol in which weak memories persist longer if exploration in a novel context is introduced around the time of memory…
Kennerley, Steven W; Wallis, Jonathan D
Although research implicates lateral prefrontal cortex (PFC) in executive control and goal-directed behavior, it remains unclear how goals influence executive processes. One possibility is that goal-relevant information, such as expected rewards, could modulate the representation of information relating to executive control, thereby ensuring the efficient allocation of cognitive resources. To investigate this, we examined how reward modulated spatial working memory. Past studies investigating spatial working memory have focused on dorsolateral PFC, but this area only weakly connects with areas processing reward. Ventrolateral PFC has better connections in this regard. Thus, we contrasted the functional properties of single neurons in ventrolateral and dorsolateral PFC as two subjects performed a task that required them to hold spatial information in working memory under different expectancies of reward for correct performance. We balanced the order of presentation of spatial and reward information so we could assess the neuronal encoding of the two pieces of information independently and conjointly. Neurons in ventrolateral PFC encoded both spatial and reward information earlier, stronger and in a more sustained manner than neurons in dorsolateral PFC. Within ventrolateral PFC, spatial selectivity was more prevalent on the inferior convexity than within the principal sulcus. Finally, when reward increased spatial selectivity, behavioral performance improved, whereas when reward decreased spatial selectivity, behavioral performance deteriorated. These results suggest that ventrolateral PFC may be a locus whereby information about expected rewards can modulate information in working memory. The pattern of results is consistent with a role for ventrolateral PFC in attentional control.
Huh, Terri J; Kramer, Joel H; Gazzaley, Adam; Delis, Dean C
Response bias reflects the decision rule an individual uses when faced with uncertainty on recognition memory tasks. Recent studies indicate frontal regions may mediate response bias performance. One theory of aging also implicates frontal lobe contributions in age-related cognitive changes. This suggests that frontal lobe changes may mediate response bias in older adults. Consistent with this frontal aging hypothesis, we predicted that response bias would become more liberal with age. Participants were 181 younger (30-49) and 112 older normal adults (75+) that were part of the California Verbal Learning Test-second edition (CVLT-2) normative sample (total n = 1078). We used parametric measures of discriminability and response bias provided by the CVLT-2 scoring program. Groups were similar in IQ and education. Multi-level regression models were created to examine the effects of moderating variables. The interaction between age and age group significantly predicted response bias. Post hoc analysis indicated that increasing age was associated with more liberal bias in the older but not in the younger group. In the light of reported relationships between frontal regions and both aging and response bias, we hypothesize that frontal changes may be the underlying mechanism explaining the increase in liberal response bias with age.
Full Text Available It is known that sleep reshapes the neural representations that subtend the memories acquired while navigating in a virtual environment. However, navigation is not process-pure, as manifold learning components contribute to performance, notably the spatial and contextual memory constituents. In this context, it remains unclear whether post-training sleep globally promotes consolidation of all of the memory components embedded in virtual navigation, or rather favors the development of specific representations. Here, we investigated the effect of post-training sleep on the neural substrates of the consolidation of spatial and contextual memories acquired while navigating in a complex 3D, naturalistic virtual town. Using fMRI, we mapped regional cerebral activity during various tasks designed to tap either the spatial or the contextual memory component, or both, 72 h after encoding with or without sleep deprivation during the first post-training night. Behavioral performance was not dependent upon post-training sleep deprivation, neither in a natural setting that engages both spatial and contextual memory processes nor when looking more specifically at each of these memory representations. At the neuronal level however, analyses that focused on contextual memory revealed distinct correlations between performance and neuronal activity in frontal areas associated with recollection processes after post-training sleep, and in the parahippocampal gyrus associated with familiarity processes in sleep-deprived participants. Likewise, efficient spatial memory was associated with posterior cortical activity after sleep whereas it correlated with parahippocampal/medial temporal activity after sleep deprivation. Finally, variations in place-finding efficiency in a natural setting encompassing spatial and contextual elements were associated with caudate activity after post-training sleep, suggesting the automation of navigation. These data indicate that post
Full Text Available Functional neuroimaging studies have noted that brain regions supporting theory of mind (ToM overlap remarkably with those underlying episodic memory, suggesting a link between the two processes. The present study shows that memory for others’ past experiences modulates significantly our appraisal of, and reaction to, what is happening to them currently. Participants read the life story of two characters; one had experienced a long series of love-related failures, the other a long series of work-related failures. In a later faux pas recognition task, participants reported more empathy for the character unlucky in love in love-related faux pas scenarios, and for the character unlucky at work in work-related faux pas scenarios. The memory-based modulation of empathy correlated with the number of details remembered from the characters’ life story. These results suggest that individuals use memory for other people’s past experiences to simulate how they feel in similar situations they are currently facing. The integration of ToM and memory processes allows adjusting mental state inferences to fit unique social targets, constructing an individualized ToM (iToM.
Campolongo, Patrizia; Roozendaal, Benno; Trezza, Viviana; Hauer, Daniela; Schelling, Gustav; McGaugh, James L.; Cuomo, Vincenzo
Extensive evidence indicates that the basolateral complex of the amygdala (BLA) modulates the consolidation of memories for emotionally arousing experiences, an effect that involves the activation of the glucocorticoid system. Because the BLA expresses high densities of cannabinoid CB1 receptors, the present experiments investigated whether the endocannabinoid system in the BLA influences memory consolidation and whether glucocorticoids interact with this system. The CB1 receptor agonist WIN5...
Solar cells, integrated circuits, and sensors are essential to manned and unmanned space flight and exploration, but such systems are highly susceptible to damage from radiation. Especially problematic, the Van Allen radiation belts encircle Earth in concentric radioactive tori at distances from about 6,300 to 38,000 km, though the inner radiation belt can dip as low as 700 km, posing a severe hazard to craft and humans leaving Earth s atmosphere. To avoid this radiation, the International Space Station and space shuttles orbit at altitudes between 275 and 460 km, below the belts range, and Apollo astronauts skirted the edge of the belts to minimize exposure, passing swiftly through thinner sections of the belts and thereby avoiding significant side effects. This radiation can, however, prove detrimental to improperly protected electronics on satellites that spend the majority of their service life in the harsh environment of the belts. Compact, high-performance electronics that can withstand extreme environmental and radiation stress are thus critical to future space missions. Increasing miniaturization of electronics addresses the need for lighter weight in launch payloads, as launch costs put weight at a premium. Likewise, improved memory technologies have reduced size, cost, mass, power demand, and system complexity, and improved high-bandwidth communication to meet the data volume needs of the next-generation high-resolution sensors. This very miniaturization, however, has exacerbated system susceptibility to radiation, as the charge of ions may meet or exceed that of circuitry, overwhelming the circuit and disrupting operation of a satellite. The Hubble Space Telescope, for example, must turn off its sensors when passing through intense radiation to maintain reliable operation. To address the need for improved data quality, additional capacity for raw and processed data, ever-increasing resolution, and radiation tolerance, NASA spurred the development of the
Boehringer, Andreas; Macher, Katja; Dukart, Juergen; Villringer, Arno; Pleger, Burkhard
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.
Elisa C Dias
Full Text Available Schizophrenia patients have deficits in cognitive function that are a core feature of the disorder. AX-CPT is commonly used to study cognition in schizophrenia, and patients have characteristic pattern of behavioral and ERP response. In AX-CPT subjects respond when a flashed cue A is followed by a target X, ignoring other letter combinations. Patients show reduced hit rate to go trials, and increased false alarms to sequences that require inhibition of a prepotent response. EEG recordings show reduced sensory (P1/N1, as well as later cognitive components (N2, P3, CNV. Behavioral deficits correlate most strongly with sensory dysfunction. Oscillatory analyses provide critical information regarding sensory/cognitive processing over and above standard ERP analyses. Recent analyses of induced oscillatory activity in single trials during AX-CPT in healthy volunteers showed characteristic response patterns in theta, alpha and beta frequencies tied to specific sensory and cognitive processes. Alpha and beta modulated during the trials and beta modulation over the frontal cortex correlated with reaction time. In this study, EEG data was obtained from 18 schizophrenia patients and 13 controls during AX-CPT performance, and single trial decomposition of the signal yielded power in the target wavelengths.Significant task-related event-related desynchronization (ERD was observed in both alpha and beta frequency bands over parieto-occipital cortex related to sensory encoding of the cue. This modulation was reduced in patients for beta, but not for alpha. In addition, significant beta ERD was observed over motor cortex, related to motor preparation for the response, and was also reduced in patients. These findings demonstrate impaired dynamic modulation of beta frequency rhythms in schizophrenia, and suggest that failures of oscillatory activity may underlie impaired sensory information processing in schizophrenia that in turn contributes to cognitive deficits.
Wang, Chunjie; Geng, Fengji; Yao, Yuan; Weng, Jian; Hu, Yuzheng; Chen, Feiyan
Our previous work demonstrated that abacus-based mental calculation (AMC), a traditional Chinese calculation method, could help children improve their math abilities (e.g. basic arithmetical ability) and executive function (e.g. working memory). This study further examined the effects of long-term AMC training on math ability in visual-spatial domain and the task switching component of executive function. More importantly, this study investigated whether AMC training modulated the relationship between math abilities and task switching. The participants were seventy 7-year-old children who were randomly assigned into AMC and control groups at primary school entry. Children in AMC group received 2-hour AMC training every week since primary school entry. On the contrary, children in the control group had never received any AMC training. Math and task switching abilities were measured one year and three years respectively after AMC training began. The results showed that AMC children performed better than their peers on math abilities in arithmetical and visual-spatial domains. In addition, AMC group responded faster than control group in the switching task, while no group difference was found in switch cost. Most interestingly, group difference was present in the relationships between math abilities and switch cost. These results implied the effect of AMC training on math abilities as well as its relationship with executive function.
Full Text Available Our previous work demonstrated that abacus-based mental calculation (AMC, a traditional Chinese calculation method, could help children improve their math abilities (e.g. basic arithmetical ability and executive function (e.g. working memory. This study further examined the effects of long-term AMC training on math ability in visual-spatial domain and the task switching component of executive function. More importantly, this study investigated whether AMC training modulated the relationship between math abilities and task switching. The participants were seventy 7-year-old children who were randomly assigned into AMC and control groups at primary school entry. Children in AMC group received 2-hour AMC training every week since primary school entry. On the contrary, children in the control group had never received any AMC training. Math and task switching abilities were measured one year and three years respectively after AMC training began. The results showed that AMC children performed better than their peers on math abilities in arithmetical and visual-spatial domains. In addition, AMC group responded faster than control group in the switching task, while no group difference was found in switch cost. Most interestingly, group difference was present in the relationships between math abilities and switch cost. These results implied the effect of AMC training on math abilities as well as its relationship with executive function.
Huang, Tracy; Loft, Shayne; Humphreys, Michael S.
"Time-based prospective memory" (PM) refers to performing intended actions at a future time. Participants with time-based PM tasks can be slower to perform ongoing tasks (costs) than participants without PM tasks because internal control is required to maintain the PM intention or to make prospective-timing estimates. However, external…
Kvavilashvili, Lia; Messer, David J.; Ebdon, Pippa
Three experiments examined effects of age and task interruption on children's prospective memory (PM), remembering to carry out a future task. Age explained a small portion of variance in performance. Children who did not have to interrupt their ongoing activity to complete the PM tasks performed significantly better than children who had to…
Harinen, Kirsi; Rinne, Teemu
We used fMRI to investigate activations within human auditory cortex (AC) to vowels during vowel discrimination, vowel (categorical n-back) memory, and visual tasks. Based on our previous studies, we hypothesized that the vowel discrimination task would be associated with increased activations in the anterior superior temporal gyrus (STG), while the vowel memory task would enhance activations in the posterior STG and inferior parietal lobule (IPL). In particular, we tested the hypothesis that activations in the IPL during vowel memory tasks are associated with categorical processing. Namely, activations due to categorical processing should be higher during tasks performed on nonphonemic (hard to categorize) than on phonemic (easy to categorize) vowels. As expected, we found distinct activation patterns during vowel discrimination and vowel memory tasks. Further, these task-dependent activations were different during tasks performed on phonemic or nonphonemic vowels. However, activations in the IPL associated with the vowel memory task were not stronger during nonphonemic than phonemic vowel blocks. Together these results demonstrate that activations in human AC to vowels depend on both the requirements of the behavioral task and the phonemic status of the vowels. Copyright © 2013 Elsevier Inc. All rights reserved.
Gonthier, Corentin; Thomassin, Noémylle; Roulin, Jean-Luc
Most studies in individual differences in the field of working memory research use complex span tasks to measure working memory capacity. Various complex span tasks based on different materials have been developed, and these tasks have proven both reliable and valid; several complex span tasks are often combined to provide a domain-general estimate of working memory capacity with even better psychometric properties. The present work sought to address two issues. Firstly, having participants perform several full-length complex span tasks in succession makes for a long and tedious procedure. Secondly, few complex span tasks have been translated and validated in French. We constructed a French working memory task labeled the Composite Complex Span (CCS). The CCS includes shortened versions of three classic complex span tasks: the reading span, symmetry span, and operation span. We assessed the psychometric properties of the CCS, including test-retest reliability and convergent validity, with Raven's Advanced Progressive Matrices and with an alpha span task; the CCS demonstrated satisfying qualities in a sample of 1,093 participants. This work provides evidence that shorter versions of classic complex span tasks can yield valid working memory estimates. The materials and normative data for the CCS are also included.
Walter, Stefan; Meier, Beat
Prospective memory performance can be enhanced by task importance, for example by promising a reward. Typically, this comes at costs in the ongoing task. However, previous research has suggested that social importance (e.g., providing a social motive) can enhance prospective memory performance without additional monitoring costs in activity-based and time-based tasks. The aim of the present study was to investigate the influence of social importance in an event-based task. We compared four conditions: social importance, promising a reward, both social importance and promising a reward, and standard prospective memory instructions (control condition). The results showed enhanced prospective memory performance for all importance conditions compared to the control condition. Although ongoing task performance was slowed in all conditions with a prospective memory task when compared to a baseline condition with no prospective memory task, additional costs occurred only when both the social importance and reward were present simultaneously. Alone, neither social importance nor promising a reward produced an additional slowing when compared to the cost in the standard (control) condition. Thus, social importance and reward can enhance event-based prospective memory at no additional cost.
Galli, Giulia; Griffiths, Victoria A; Otten, Leun J
It has been shown that the effectiveness with which unpleasant events are encoded into memory is related to brain activity set in train before the events. Here, we assessed whether encoding-related activity before an aversive event can be modulated by emotion regulation. Electrical brain activity was recorded from the scalps of healthy women while they performed an incidental encoding task on randomly intermixed unpleasant and neutral visual scenes. A cue presented 1.5 s before each picture indicated the upcoming valence. In half of the blocks of trials, the instructions emphasized to let emotions arise in a natural way. In the other half, participants were asked to decrease their emotional response by adopting the perspective of a detached observer. Memory for the scenes was probed 1 day later with a recognition memory test. Brain activity before unpleasant scenes predicted later memory of the scenes, but only when participants felt their emotions and did not detach from them. The findings indicate that emotion regulation can eliminate the influence of anticipatory brain activity on memory encoding. This may be relevant for the understanding and treatment of psychiatric diseases with a memory component.
Theodore A Evans
Full Text Available Prospective memory is remembering to do something at a future time. A growing body of research supports that prospective memory may exist in nonhuman animals, but the methods used to test nonhuman prospective memory differ from those used with humans. The current work tests prospective memory in chimpanzees using a method that closely approximates a typical human paradigm. In these experiments, the prospective memory cue was embedded within an ongoing task. Tokens representing food items could be used in one of two ways: in a matching task with pictures of items (the ongoing task or to request a food item hidden in a different location at the beginning of the trial. Chimpanzees had to disengage from the ongoing task in order to use the appropriate token to obtain a higher preference food item. In Experiment 1, chimpanzees effectively matched tokens to pictures, when appropriate, and disengaged from the ongoing task when the token matched the hidden item. In Experiment 2, performance did not differ when the target item was either hidden or visible. This suggested no effect of cognitive load on either the prospective memory task or the ongoing task, but performance was near ceiling, which may have contributed to this outcome. In Experiment 3, we created a more challenging version of the task. More errors on the matching task occurred before the prospective memory had been carried out, and this difference seemed to be limited to the hidden condition. This finding parallels results from human studies and suggests that working memory load and prospective memory may have a similar relationship in nonhuman primates.
Di Stasi, Leandro L; Diaz-Piedra, Carolina; Suárez, Juan; McCamy, Michael B; Martinez-Conde, Susana; Roca-Dorda, Joaquín; Catena, Andrés
Most research connecting task performance and neural activity to date has been conducted in laboratory conditions. Thus, field studies remain scarce, especially in extreme conditions such as during real flights. Here, we investigated the effects of flight procedures of varied complexity on the in-flight EEG activity of military helicopter pilots. Flight procedural complexity modulated the EEG power spectrum: highly demanding procedures (i.e., takeoff and landing) were associated with higher EEG power in the higher frequency bands, whereas less demanding procedures (i.e., flight exercises) were associated with lower EEG power over the same frequency bands. These results suggest that EEG recordings may help to evaluate an operator's cognitive performance in challenging real-life scenarios, and thus could aid in the prevention of catastrophic events. © 2015 Society for Psychophysiological Research.
Hawley, Wayne R; Grissom, Elin M; Martin, Ryan C; Halmos, Miklos B; Bart, Corrine L S; Dohanich, Gary P
A growing body of research indicates that testosterone influences spatial cognition in male rats; however, the overwhelming majority of studies have been conducted on tasks motivated by either food deprivation or water escape. The hippocampus-dependent version of the Y-maze task, which characterizes spatial recognition memory, capitalizes on the propensity of rats to gravitate toward novel spatial environments and is not contingent upon either appetite or the stress associated with water escape, two factors also affected by testosterone. Accordingly, the aim of the current study was to examine the effects of orchidectomy and subsequent testosterone treatment on spatial recognition memory. Orchidectomy did not impact spatial recognition memory when the delay between the information and retention trials of the Y-maze task was 24h. Alternatively, on the second Y-maze task, which featured a 48-h delay between trials, orchidectomy reduced, and treatments that produced higher levels of testosterone restored, preference for the arm associated with the novel spatial environment. Importantly, there were no differences in activity levels as a function of orchidectomy or testosterone treatment on either of the two tasks. Consistent with previous findings, orchidectomy attenuated, and testosterone treatment restored, both body weight gain and the relative weight of the androgen-sensitive ischiocavernosus muscle, which confirmed the efficacy of orchidectomy and testosterone treatments on physiological outcomes. Therefore, testosterone influenced spatial cognition on a task that minimized the influence of non-mnemonic factors and took advantage of the innate preference of rodents to seek out novel spatial environments. Copyright © 2013 Elsevier Inc. All rights reserved.
Krawczyk, Daniel C; D'Esposito, Mark
Cognitive performance is affected by motivation. Few studies, however, have investigated the neural mechanisms of the influence of motivation through potential monetary punishment on working memory. We employed functional MRI during a delayed recognition task that manipulated top-down control demands with added monetary incentives to some trials in the form of potential losses of bonus money. Behavioral performance on the task was influenced by loss-threatening incentives in the form of faster and more accurate performance. As shown previously, we found enhancement of activity for relevant stimuli occurs throughout all task periods (e.g., stimulus encoding, maintenance, and response) in both prefrontal and visual association cortex. Further, these activation patterns were enhanced for trials with possible monetary loss relative to nonincentive trials. During the incentive cue, the amygdala and striatum showed significantly greater activation when money was at a possible loss on the trial. We also evaluated patterns of functional connectivity between regions responsive to monetary consequences and prefrontal areas responsive to the task. This analysis revealed greater delay period connectivity between and the left insula and prefrontal cortex with possible monetary loss relative to nonincentive trials. Overall, these results reveal that incentive motivation can modulate performance on working memory tasks through top-down signals via amplification of activity within prefrontal and visual association regions selective to processing the perceptual inputs of the stimuli to be remembered. Copyright © 2011 Wiley Periodicals, Inc.
Campolongo, Patrizia; Roozendaal, Benno; Trezza, Viviana; Hauer, Daniela; Schelling, Gustav; McGaugh, James L.; Cuomo, Vincenzo
Extensive evidence indicates that the basolateral complex of the amygdala (BLA) modulates the consolidation of memories for emotionally arousing experiences, an effect that involves the activation of the glucocorticoid system. Because the BLA expresses high densities of cannabinoid CB1 receptors,
León, Irene; Cimadevilla, José Manuel; Tascón, Laura
Behavioral achievements are the product of brain maturation. During postnatal development, the medial temporal lobe completes its maturation, and children acquire new memory abilities. In recent years, virtual reality-based tasks have been introduced in the neuropsychology field to assess different cognitive functions. In this work, desktop virtual reality tasks are combined with classic psychometric tests to assess spatial abilities in 4- to 10-year-old children. Fifty boys and 50 girls 4-10-years of age participated in this study. Spatial reference memory and spatial working memory were assessed using a desktop virtual reality-based task. Other classic psychometric tests were also included in this work (e.g., the Corsi Block Tapping Test, digit tests, 10/36 Spatial Recall Test). In general terms, 4- and 5-year-old groups showed poorer performance than the older groups. However, 5-year-old children showed basic spatial navigation abilities with little difficulty. In addition, boys outperformed girls from the 6-8-year-old groups. Gender differences only emerged in the reference-memory version of the spatial task, whereas both sexes displayed similar performances in the working-memory version. There was general improvement in the performance of different tasks in children older than 5 years. However, results also suggest that brain regions involved in allocentric memory are functional even at the age of 5. In addition, the brain structures underlying reference memory mature later in girls than those required for the working memory.
Vladimir A. Markov, Ph.D.
High capacity, high transfer rate, random access memory systems are needed to archive and distribute the tremendous volume of digital information being generated, for example, the human genome mapping and online libraries. The development of multi-gigabit per second networks underscores the need for next-generation archival memory systems. During Phase I we conducted the theoretical analysis and accomplished experimental tests that validated the key aspects of the ultra-high density holographic data storage module with high transfer rate. We also inspected the secure nature of the encoding method and estimated the performance of full-scale system. Two basic architectures were considered, allowing for reversible compact solid-state configuration with limited capacity, and very large capacity write once read many memory system.
Vercammen, Charlotte; Goossens, Tine; Wouters, Jan; van Wieringen, Astrid
The main objective of this study is to investigate memory task performance in different age groups, irrespective of hearing status. Data are collected on a short-term memory task (WAIS-III Digit Span forward) and two working memory tasks (WAIS-III Digit Span backward and the Reading Span Test). The tasks are administered to young (20-30 years, n = 56), middle-aged (50-60 years, n = 47), and older participants (70-80 years, n = 16) with normal hearing thresholds. All participants have passed a cognitive screening task (Montreal Cognitive Assessment (MoCA)). Young participants perform significantly better than middle-aged participants, while middle-aged and older participants perform similarly on the three memory tasks. Our data show that older clinically normal hearing persons perform equally well on the memory tasks as middle-aged persons. However, even under optimal conditions of preserved sensory processing, changes in memory performance occur. Based on our data, these changes set in before middle age.
Merkel, Stephen P.; Hall, Vernon C.
Measures of memory for order were correlated with measures requiring mental manipulation, achievement, and aptitude using college and fifth grade students. A significant relationship was found for fifth graders but not for college students, suggesting that the nature and capacity of short-term memory changes with age. (Author/PN)
Lewandowsky, Stephan; Yang, Lee-Xieng; Newell, Ben R.; Kalish, Michael L.
Working memory is crucial for many higher level cognitive functions, ranging from mental arithmetic to reasoning and problem solving. Likewise, the ability to learn and categorize novel concepts forms an indispensable part of human cognition. However, very little is known about the relationship between working memory and categorization. This…
Zhao, Xin; Xu, Yiwenjie; Fu, Junjun; Maes, Joseph H R
Previous studies examining effects of working memory (WM) updating training revealed mixed results. One factor that might modulate training gains, and possibly also transfer of those gains to non-trained cognitive tasks, is achievement motivation. In the present Studies 1 and 2, students with either a high (HAM) or low (LAM) achievement motivation completed a 14-day visuospatial WM updating training program. In Study 2, the students also performed a set of tasks measuring other executive functions and fluid intelligence prior to and after training. In both studies, the HAM students displayed a larger training gain than the LAM students. Study 2 revealed that after training, both groups showed better performance on the near-transfer but not far-transfer tasks. Importantly, the differential training gain was not associated with better post-training performance for the HAM compared to the LAM students on any of the transfer tasks. These results are taken to support a modulatory role of achievement motivation on WM training benefits, but not on transfer of those benefits to other tasks. Possible reasons for the general improvement on the near-transfer tasks and the absence of a modulatory role of achievement motivation on transfer-task performance are discussed.
Altgassen, Mareike; Koban, Nancy; Kliegel, Matthias
The present study is the first to directly compare event- and time-based prospective memory in Autism Spectrum Disorders (ASD) using a contextual task mirroring real life demands of prospective memory. Twenty-five individuals with ASD and 25 age- and ability-matched controls completed the Dresden Breakfast task which required participants to prepare breakfast following a set of rules and time restrictions. Overall, adults with ASD had less correct time- and event-based prospective memory responses in comparison to controls, which is consistent with previous research in children with ASD. Moreover, ASD participants completed fewer tasks, followed rules less closely, and monitored the elapsing time less closely than controls. Individuals with ASD seem not to be compensating in naturalistic prospective memory tasks.
Kirschner, Femke; Paas, Fred; Kirschner, Paul A.
Kirschner, F., Paas, F., & Kirschner, P. A. (2011). Task complexity as a driver for collaborative learning efficiency: The collective working-memory effect. Applied Cognitive Psychology, 25, 615–624. doi: 10.1002/acp.1730.
McReynolds, Jayme R.; Anderson, Kelly M.; Donowho, Kyle M.; McIntyre, Christa K.
The basolateral complex of the amygdala (BLA) plays a role in the modulation of emotional memory consolidation through its interactions with other brain regions. In rats, memory enhancing infusions of the β-adrenergic receptor agonist clenbuterol into the BLA immediately after training enhances expression of the protein product of the immediate early gene Arc in the dorsal hippocampus and memory-impairing intra-BLA treatments reduce hippocampal Arc expression. We have proposed that the BLA may modulate memory consolidation through an influence on the local translation of synaptic plasticity proteins, like Arc, in recently active synapses in efferent brain regions. To date, all work related to this hypothesis is based on aversive memory tasks such as inhibitory avoidance (IA). To determine whether BLA modulation of hippocampal Arc protein expression is specific to plasticity associated with inhibitory avoidance memory, or a common mechanism for multiple types of memory, we tested the effect of intra-BLA infusions of clenbuterol on memory and hippocampal synaptic Arc expression following IA or object recognition training. Results indicate that intra-BLA infusions of clenbuterol enhance memory for both tasks; however, Arc expression in hippocampal synaptoneurosomes was significantly elevated only in rats trained on the aversive IA task. These findings suggest that regulation of Arc expression in hippocampal synapses may depend on co-activation of arousal systems. To test this hypothesis, a “high arousal” version of the OR task was used where rats were not habituated to the testing conditions. Posttraining intra-BLA infusions of clenbuterol enhanced consolidation of the high-arousing version of the task and significantly increased Arc protein levels in dorsal hippocampus synaptic fractions. These findings suggest that the BLA modulates multiple forms of memory and affects the synaptic plasticity-associated protein Arc in synapses of the dorsal hippocampus when
Zhang, Hongxia; Tang, Weihai; Liu, Xiping
Remembering to perform an action when a specific event occurs is referred to as Event-Based Prospective Memory (EBPM). This study investigated how EBPM performance is affected by task duration by having university students ( n = 223) perform an EBPM task that was embedded within an ongoing computer-based color-matching task. For this experiment, we separated the overall task's duration into the filler task duration and the ongoing task duration. The filler task duration is the length of time between the intention and the beginning of the ongoing task, and the ongoing task duration is the length of time between the beginning of the ongoing task and the appearance of the first Prospective Memory (PM) cue. The filler task duration and ongoing task duration were further divided into three levels: 3, 6, and 9 min. Two factors were then orthogonally manipulated between-subjects using a multinomial processing tree model to separate the effects of different task durations on the two EBPM components. A mediation model was then created to verify whether task duration influences EBPM via self-reminding or discrimination. The results reveal three points. (1) Lengthening the duration of ongoing tasks had a negative effect on EBPM performance while lengthening the duration of the filler task had no significant effect on it. (2) As the filler task was lengthened, both the prospective and retrospective components show a decreasing and then increasing trend. Also, when the ongoing task duration was lengthened, the prospective component decreased while the retrospective component significantly increased. (3) The mediating effect of discrimination between the task duration and EBPM performance was significant. We concluded that different task durations influence EBPM performance through different components with discrimination being the mediator between task duration and EBPM performance.
Wamsley, Erin J; Tucker, Matthew; Payne, Jessica D; Benavides, Joseph A; Stickgold, Robert
It is now well established that postlearning sleep is beneficial for human memory performance. Meanwhile, human and animal studies have demonstrated that learning-related neural activity is re-expressed during posttraining nonrapid eye movement (NREM) sleep. NREM sleep processes appear to be particularly beneficial for hippocampus-dependent forms of memory. These observations suggest that learning triggers the reactivation and reorganization of memory traces during sleep, a systems-level process that in turn enhances behavioral performance. Here, we hypothesized that dreaming about a learning experience during NREM sleep would be associated with improved performance on a hippocampus-dependent spatial memory task. Subjects were trained on a virtual navigation task and then retested on the same task 5 hr after initial training. Improved performance at retest was strongly associated with task-related dream imagery during an intervening afternoon nap. Task-related thoughts during wakefulness, in contrast, did not predict improved performance. These observations suggest that sleep-dependent memory consolidation in humans is facilitated by the offline reactivation of recently formed memories, and furthermore that dream experiences reflect this memory processing. That similar effects were not observed during wakefulness suggests that these mnemonic processes are specific to the sleep state. (c) 2010 Elsevier Ltd. All rights reserved.
Ram-Tsur, Ronit; Faust, Miriam; Zivotofsky, Ari Z.
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…
Schicknick, Horst; Reichenbach, Nicole; Smalla, Karl-Heinz; Scheich, Henning; Gundelfinger, Eckart D; Tischmeyer, Wolfgang
In Mongolian gerbils, the auditory cortex is critical for discriminating rising vs. falling frequency-modulated tones. Based on our previous studies, we hypothesized that dopaminergic inputs to the auditory cortex during and shortly after acquisition of the discrimination strategy control long-term memory formation. To test this hypothesis, we studied frequency-modulated tone discrimination learning of gerbils in a shuttle box GO/NO-GO procedure following differential treatments. (i) Pre-exposure of gerbils to the frequency-modulated tones at 1 day before the first discrimination training session severely impaired the accuracy of the discrimination acquired in that session during the initial trials of a second training session, performed 1 day later. (ii) Local injection of the D1/D5 dopamine receptor antagonist SCH-23390 into the auditory cortex after task acquisition caused a discrimination deficit of similar extent and time course as with pre-exposure. This effect was dependent on the dose and time point of injection. (iii) Injection of the D1/D5 dopamine receptor agonist SKF-38393 into the auditory cortex after retraining caused a further discrimination improvement at the beginning of subsequent sessions. All three treatments, which supposedly interfered with dopamine signalling during conditioning and/or retraining, had a substantial impact on the dynamics of the discrimination performance particularly at the beginning of subsequent training sessions. These findings suggest that auditory-cortical dopamine activity after acquisition of a discrimination of complex sounds and after retrieval of weak frequency-modulated tone discrimination memory further improves memory consolidation, i.e. the correct association of two sounds with their respective GO/NO-GO meaning, in support of future memory recall. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.
Blades, Mark; Banham, Jessica
Described is an investigation that determined whether young children have schemas for environmental information. The results are discussed with reference to the importance of memory schemas for learning about the environment. (KR)
Full Text Available Remembering to perform an action when a specific event occurs is referred to as Event-Based Prospective Memory (EBPM. This study investigated how EBPM performance is affected by task duration by having university students (n = 223 perform an EBPM task that was embedded within an ongoing computer-based color-matching task. For this experiment, we separated the overall task’s duration into the filler task duration and the ongoing task duration. The filler task duration is the length of time between the intention and the beginning of the ongoing task, and the ongoing task duration is the length of time between the beginning of the ongoing task and the appearance of the first Prospective Memory (PM cue. The filler task duration and ongoing task duration were further divided into three levels: 3, 6, and 9 min. Two factors were then orthogonally manipulated between-subjects using a multinomial processing tree model to separate the effects of different task durations on the two EBPM components. A mediation model was then created to verify whether task duration influences EBPM via self-reminding or discrimination. The results reveal three points. (1 Lengthening the duration of ongoing tasks had a negative effect on EBPM performance while lengthening the duration of the filler task had no significant effect on it. (2 As the filler task was lengthened, both the prospective and retrospective components show a decreasing and then increasing trend. Also, when the ongoing task duration was lengthened, the prospective component decreased while the retrospective component significantly increased. (3 The mediating effect of discrimination between the task duration and EBPM performance was significant. We concluded that different task durations influence EBPM performance through different components with discrimination being the mediator between task duration and EBPM performance.
Full Text Available Working memory (WM is a neural system responsible for the temporary storage of information and its utilization in problem solving. The central executive is theorized as the controller of storage functions that support WM. Neurophysiological data suggest that EEG theta and alpha oscillations in frontal and midline regions are involved in neural communication between the central executive and storage functions during WM performance. Emotion is known to modulate several memory systems, including WM, through central and peripheral pathways. However, the physiological correlations (electroencephalographic – EEG; autonomic nervous activity of the effect of emotion over WM are not well described. In this study we aimed to identify physiological responses related to emotional WM performance. EEG (21 channels, heart rate (HR and galvanic skin response (GSR recordings were obtained from 54 volunteers while performing delayed matching and non-matching to sample tasks (DMTS/DNMTS. Emotional and neutral pictures from the International Affective Picture System and geometric figures were used as stimuli. As expected, WM performance was accompanied by presence of theta (frontal and midline electrodes and Alpha power (parietal electrodes. Beta and gamma oscillations were concentrated in frontopolar and left temporal regions. DNMTS task was accompanied by increases in Beta power, HR and GSR compared to DMTS task. Correlation analysis showed a positive tendency for gamma in Fp2 site, ratio of LF/HF (HR low and high frequency and skin conductance in both tasks. The HR results indicate an inverse reaction related to parasympathetic and sympathetic nervous system during the performance of the tasks. Taken together, our results contribute to elucidate the complex interactions between central and autonomic nervous systems in the modulation of emotional WM tasks.
Zhang, Xiaofan; Yi, Hu; Bai, Wenwen; Tian, Xin
Working memory plays an important role in complex cognitive tasks. A popular theoretical view is that transient properties of neuronal dynamics underlie cognitive processing. The question raised here as to how the transient dynamics evolve in working memory. To address this issue, we investigated the multiple single-unit activity dynamics in rat medial prefrontal cortex (mPFC) during a Y-maze working memory task. The approach worked by reconstructing state space from delays of the original single-unit firing rate variables, which were further analyzed using kernel principal component analysis (KPCA). Then the neural trajectories were obtained to visualize the multiple single-unit activity. Furthermore, the maximal Lyapunov exponent (MLE) was calculated to quantitatively evaluate the neural trajectories during the working memory task. The results showed that the neuronal activity produced stable and reproducible neural trajectories in the correct trials while showed irregular trajectories in the incorrect trials, which may establish a link between the neurocognitive process and behavioral performance in working memory. The MLEs significantly increased during working memory in the correctly performed trials, indicating an increased divergence of the neural trajectories. In the incorrect trials, the MLEs were nearly zero and remained unchanged during the task. Taken together, the trial-specific neural trajectory provides an effective way to track the instantaneous state of the neuronal population during the working memory task and offers valuable insights into working memory function. The MLE describes the changes of neural dynamics in working memory and may reflect different neuronal population states in working memory.
Hollingworth, Andrew; Matsukura, Michi; Luck, Steven J.
In three experiments, we examined the influence of visual working memory (VWM) on the metrics of saccade landing position in a global effect paradigm. Participants executed a saccade to the more eccentric object in an object pair appearing on the horizontal midline, to the left or right of central fixation. While completing the saccade task, participants maintained a color in VWM for an unrelated memory task. Either the color of the saccade target matched the memory color (target match), the color of the distractor matched the memory color (distractor match), or the colors of neither object matched the memory color (no match). In the no-match condition, saccades tended to land at the midpoint between the two objects: the global, or averaging, effect. However, when one of the two objects matched VWM, the distribution of landing position shifted toward the matching object, both for target match and for distractor match. VWM modulation of landing position was observed even for the fastest quartile of saccades, with a mean latency as low as 112 ms. Effects of VWM on such rapidly generated saccades, with latencies in the express-saccade range, indicate that VWM interacts with the initial sweep of visual sensory processing, modulating perceptual input to oculomotor systems and thereby biasing oculomotor selection. As a result, differences in memory match produce effects on landing position similar to the effects generated by differences in physical salience. PMID:24190909
Hollingworth, Andrew; Matsukura, Michi; Luck, Steven J
In three experiments, we examined the influence of visual working memory (VWM) on the metrics of saccade landing position in a global effect paradigm. Participants executed a saccade to the more eccentric object in an object pair appearing on the horizontal midline, to the left or right of central fixation. While completing the saccade task, participants maintained a color in VWM for an unrelated memory task. Either the color of the saccade target matched the memory color (target match), the color of the distractor matched the memory color (distractor match), or the colors of neither object matched the memory color (no match). In the no-match condition, saccades tended to land at the midpoint between the two objects: the global, or averaging, effect. However, when one of the two objects matched VWM, the distribution of landing position shifted toward the matching object, both for target match and for distractor match. VWM modulation of landing position was observed even for the fastest quartile of saccades, with a mean latency as low as 112 ms. Effects of VWM on such rapidly generated saccades, with latencies in the express-saccade range, indicate that VWM interacts with the initial sweep of visual sensory processing, modulating perceptual input to oculomotor systems and thereby biasing oculomotor selection. As a result, differences in memory match produce effects on landing position similar to the effects generated by differences in physical salience.
Seemüller, A; Müller, E M; Rösler, F
We investigated EEG-power and EEG-coherence changes in a unimodal and a crossmodal matching-to-sample working memory task with either visual or kinesthetic stimuli. Angle-shaped trajectories were used as stimuli presented either as a moving dot on a screen or as a passive movement of a haptic device. Effects were evaluated during the different phases of encoding, maintenance, and recognition. Alpha power was modulated during encoding by the stimulus modality, and in crossmodal conditions during encoding and maintenance by the expected modality of the upcoming test stimulus. These power modulations were observed over modality-specific cortex regions. Systematic changes of coherence for crossmodal compared to unimodal tasks were not observed during encoding and maintenance but only during recognition. There, coherence in the theta-band increased between electrode sites over left central and occipital cortex areas in the crossmodal compared to the unimodal conditions. The results underline the importance of modality-specific representations and processes in unimodal and crossmodal working memory tasks. Crossmodal recognition of visually and kinesthetically presented object features seems to be related to a direct interaction of somatosensory/motor and visual cortex regions by means of long-range synchronization in the theta-band and such interactions seem to take place at the beginning of the recognition phase, i.e. when crossmodal transfer is actually necessary. Copyright © 2011 Elsevier B.V. All rights reserved.
Pirmoradi, Mona; Jemel, Boutheina; Gallagher, Anne; Tremblay, Julie; D'Hondt, Fabien; Nguyen, Dang Khoa; Béland, Renée; Lassonde, Maryse
The aim of this study was to develop a presurgical magnetoencephalography (MEG) protocol to localize and lateralize expressive and receptive language function as well as verbal memory in patients with epilepsy. Two simple language tasks and a different analytical procedure were developed. Ten healthy participants and 13 epileptic patients completed two language tasks during MEG recording: a verbal memory task and a verbal fluency task. As a first step, principal component analyses (PCA) were performed on source data from the group of healthy participants to identify spatiotemporal factors that were relevant to these paradigms. Averaged source data were used to localize areas activated during each task and a laterality index (LI) was computed on an individual basis for both groups, healthy participants and patients, using sensor data. PCA revealed activation in the left temporal lobe (300 ms) during the verbal memory task, and from the frontal lobe (210 ms) to the temporal lobe (500 ms) during the verbal fluency task in healthy participants. Averaged source data showed activity in the left hemisphere (250-750 ms), in Wernicke's area, for all participants. Left hemisphere dominance was demonstrated better using the verbal memory task than the verbal fluency task (F1,19=4.41, p=0.049). Cohen's kappa statistic revealed 93% agreement (k=0.67, p=0.002) between LIs obtained from MEG sensor data and fMRI, the IAT, electrical cortical stimulation or handedness with the verbal memory task for all participants. At 74%, agreement results for the verbal fluency task did not reach statistical significance. Analysis procedures yielded interesting findings with both tasks and localized language-related activation. However, based on source localization and laterality indices, the verbal memory task yielded better results in the context of the presurgical evaluation of epileptic patients. The verbal fluency task did not add any further information to the verbal memory task as
Smithson, Lisa; Nicoladis, Elena
Physiological arousal that occurs during narrative production is thought to reflect emotional processing and cognitive effort (Bar-Haim et al. in Dev Psychobiol 44:238-249, 2004). The purpose of this study was to determine whether individual differences in visuospatial working memory and/or verbal working memory capacity predict physiological arousal in a narrative task. Visuospatial working memory was a significant predictor of skin conductance level (SCL); verbal working memory was not. When visuospatial working memory interference was imposed, visuospatial working memory was no longer a significant predictor of SCL. Visuospatial interference also resulted in a significant reduction in SCL. Furthermore, listener ratings of narrative quality were contingent upon the visuospatial working memory resources of the narrator. Potential implications for educators and clinical practitioners are discussed.
Chiu, George L.; Eichenberger, Alexandre E.; O'Brien, John K. P.
The present disclosure relates generally to a dedicated memory structure (that is, hardware device) holding data for detecting available worker thread(s) and informing available worker thread(s) of task(s) to execute.
Festini, Sara B; Reuter-Lorenz, Patricia A
Directed forgetting requires the voluntary control of memory. Whereas many studies have examined directed forgetting in long-term memory (LTM), the mechanisms and effects of directed forgetting within working memory (WM) are less well understood. The current study tests how directed forgetting instructions delivered in a WM task influence veridical memory, as well as false memory, over the short and long term. In a modified item recognition task Experiment 1 tested WM only and demonstrated that directed forgetting reduces false recognition errors and semantic interference. Experiment 2 replicated these WM effects and used a surprise LTM recognition test to assess the long-term effects of directed forgetting in WM. Long-term veridical memory for to-be-remembered lists was better than memory for to-be-forgotten lists-the directed forgetting effect. Moreover, fewer false memories emerged for to-be-forgotten information than for to-be-remembered information in LTM as well. These results indicate that directed forgetting during WM reduces semantic processing of to-be-forgotten lists over the short and long term. Implications for theories of false memory and the mechanisms of directed forgetting within working memory are discussed.
Krimsky, Marissa; Forster, Daniel E; Llabre, Maria M; Jha, Amishi P
Working memory relies on executive resources for successful task performance, with higher demands necessitating greater resource engagement. In addition to mnemonic demands, prior studies suggest that internal sources of distraction, such as mind wandering (i.e., having off-task thoughts) and greater time on task, may tax executive resources. Herein, the consequences of mnemonic demand, mind wandering, and time on task were investigated during a visual working memory task. Participants (N=143) completed a delayed-recognition visual working memory task, with mnemonic load for visual objects manipulated across trials (1 item=low load; 2 items=high load) and subjective mind wandering assessed intermittently throughout the experiment using a self-report Likert-type scale (1=on-task, 6=off-task). Task performance (correct/incorrect response) and self-reported mind wandering data were evaluated by hierarchical linear modeling to track trial-by-trial fluctuations. Performance declined with greater time on task, and the rate of decline was steeper for high vs low load trials. Self-reported mind wandering increased over time, and significantly varied asa function of both load and time on task. Participants reported greater mind wandering at the beginning of the experiment for low vs. high load trials; however, with greater time on task, more mind wandering was reported during high vs. low load trials. These results suggest that the availability of executive resources in support of working memory maintenance processes fluctuates in a demand-sensitive manner with time on task, and may be commandeered by mind wandering. Copyright © 2017 Elsevier B.V. All rights reserved.
Varma, S.; Takashima, A.; Krewinkel, S.C.; Kooten, M.E. van; Fu, L.; Medendorp, W.P.; Kessels, R.P.C.; Daselaar, S.M.
So far, studies that investigated interference effects of post-learning processes on episodic memory consolidation in humans have only used tasks involving complex and meaningful information. Such tasks require reallocation of general or encoding-specific resources away from consolidation-relevant
McFarland, Craig P.; Glisky, Elizabeth L.
Time-based prospective memory (PM) has been found to be negatively affected by aging, possibly as a result of declining frontal lobe (FL) function. Despite a clear retrospective component to PM tasks, the medial temporal lobes (MTL) are thought to play only a secondary role in successful task completion. The present study investigated the role of…
Li, Shaofeng; Fu, Mengxia
This study investigated the comparative effects of strategic and unpressured within-task planning on second language (L2) Chinese oral production and the role of working memory in mediating the effects of the two types of planning. Twenty-nine L2 Chinese learners at a large New Zealand university performed a narrative task after watching a…
Hering, A.; Cortez, S.A.; Kliegel, M.; Altgassen, A.M.
The present study aimed at investigating age-related differences in prospective memory performance using a paradigm with high ecological validity and experimental control. Thirty old and 30 young adults completed the Dresden Breakfast task; a meal preparation task in the lab that comprises several
Recent results from Vo and Wolfe (2012b) suggest that the application of memory to visual search may be task specific: Previous experience searching for an object facilitated later search for that object, but object information acquired during a different task did not appear to transfer to search. The latter inference depended on evidence that a…
Koshino, Hideya; Minamoto, Takehiro; Yaoi, Ken; Osaka, Mariko; Osaka, Naoyuki
The Default Mode Network (DMN) regions exhibit deactivation during a wide variety of resource demanding tasks. However, recent brain imaging studies reported that they also show activation during various cognitive activities. In addition, studies have found a negative correlation between the DMN and the working memory network (WMN). Here, we investigated activity in the DMN and WMN regions during preparation and execution phases of a verbal working memory task. Results showed that the core DMN regions, including the medial prefrontal cortex and posterior cingulate cortex, and WMN regions were activated during preparation. During execution, however, the WMN regions were activated but the DMN regions were deactivated. The results suggest that activation of these network regions is affected by allocation of attentional resources to the task relevant regions due to task demands. This study extends our previous results by showing that the core DMN regions exhibit activation during task preparation and deactivation during task execution.
Elvemo, Nicolas A; Landrø, Nils I; Borchgrevink, Petter C; Håberg, Asta K
Patients with chronic pain (CP) are often reported to have deficits in working memory. Pain impairs working memory, but so do depression and sleep problems, which are also common in CP. Depression has been linked to changes in brain activity in CP during working memory tasks, but the effect of sleep problems on working memory performance and brain activity remains to be investigated. Fifteen CP patients and 17 age-, sex-, and education-matched controls underwent blood-oxygen-level dependent (BOLD) functional magnetic resonance imaging at 3T while performing block design 0-back, 2-back, and paced visual serial addition test paradigms. Subjects also reported their level of pain (Brief Pain Inventory), depression (Beck Depression Inventory II), and sleep problems (Pittsburgh Sleep Quality Index) and were tested outside the scanner with neuropsychological tests of working memory. The CP group reported significantly higher levels of pain, depression, and sleep problems. No significant performance difference was found on the neuropsychological tests in or outside the scanner between the two groups. There were no correlations between level of pain, depression, and sleep problems or between these and the neuropsychological test scores. CP patients exhibited significantly less brain activation and deactivation than controls in parietal and frontal lobes, which are the brain areas that normally show activation and deactivation during working memory tasks. Sleep problems independently and significantly modulated the BOLD response to the complex working memory tasks and were associated with decreased brain activation in task-positive regions and decreased deactivation in the default mode network in the CP group compared to the control group. The pain and depression scores covaried with working memory activation. Sleep problems in CP patients had a significant impact on the BOLD response during working memory tasks, independent of pain level and depression, even when
Cruz, Gabriela; Miyakoshi, Makoto; Makeig, Scott; Kilborn, Kerry; Evans, Jonathan
The present study examined whether Event-Related Potential (ERP) components and their neural generators are common to perceptual and conceptual prospective memory (PM) tasks or specific to the form of PM cue involved. We used Independent Component Analysis (ICA) to study the contributions of brain source activities to scalp ERPs across the different phases of two event-based PM-tasks: (1) holding intentions during a delay (monitoring) (2) detecting the correct context to perform the delayed intention (cue detection) and (3) carrying out the action (realisation of delayed intentions). Results showed that monitoring for both perceptual and conceptual PM-tasks was characterised by an enhanced early occipital negativity (N200). In addition the conceptual PM-task showed a long-lasting effect of monitoring significant around 700ms. Perceptual PM-task cues elicited an N300 enhancement associated with cue detection, whereas a midline N400-like response was evoked by conceptual PM-task cues. The Prospective Positivity associated with realisation of delayed intentions was observed in both conceptual and perceptual tasks. A common frontal-midline brain source contributed to the Prospective Positivity in both tasks and a strong contribution from parieto-frontal brain sources was observed only for the perceptually cued PM-task. These findings support the idea that: (1) The enhanced N200 can be understood as a neural correlate of a 'retrieval mode' for perceptual and conceptual PM-tasks, and additional strategic monitoring is implemented according the nature of the PM task; (2) ERPs associated with cue detection are specific to the nature of the PM cues; (3) Prospective Positivity reflects a general PM process, but the specific brain sources contributing to it depend upon the nature of the PM task. Copyright © 2016 Elsevier Ltd. All rights reserved.
Guastello, Stephen J; Boeh, Henry; Schimmels, Michael; Gorin, Hillary; Huschen, Samuel; Davis, Erin; Peters, Natalie E; Fabisch, Megan; Poston, Kirsten
The aim of this study was to evaluate two cusp catastrophe models for cognitive workload and fatigue. They share similar cubic polynomial structures but derive from different underlying processes and contain variables that contribute to flexibility with respect to load and the ability to compensate for fatigue. Cognitive workload and fatigue both have a negative impact on performance and have been difficult to separate. Extended time on task can produce fatigue, but it can also produce a positive effect from learning or automaticity. In this two-part experiment, 129 undergraduates performed tasks involving spelling, arithmetic, memory, and visual search. The fatigue cusp for the central memory task was supported with the quantity of work performed and performance on an episodic memory task acting as the control parameters. There was a strong linear effect, however. The load manipulations for the central task were competition with another participant for rewards, incentive conditions, and time pressure. Results supported the workload cusp in which trait anxiety and the incentive manipulation acted as the control parameters. The cusps are generally better than linear models for analyzing workload and fatigue phenomena; practice effects can override fatigue. Future research should investigate multitasking and task sequencing issues, physical-cognitive task combinations, and a broader range of variables that contribute to flexibility with respect to load or compensate for fatigue. The new experimental medium and analytic strategy can be generalized to virtually any real-world cognitively demanding tasks. The particular results are generalizable to tasks involving visual search.
Osaka, Mariko; Yaoi, Ken; Otsuka, Yuki; Katsuhara, Maya; Osaka, Naoyuki
Effects of practice on a conflict task in elderly individuals are examined with a focus on its impact on executive function in working memory. During a short-term practice period, healthy elderly participants practiced switching attention using a Stroop task that involved a conflict between a task relevant stimulus and an irrelevant stimulus. To explore neural substrates underlying practice effects, two working memory tasks were used: a focus reading span test (F-RST) and a non-focus reading span test (NF-RST); the NF-RST test demanded greater switching attention due to a conflict between the relevant task stimulus and an irrelevant task stimulus, thus requiring an attention switch from the latter to the former. Following the Stroop task practice, fMRI data showed that participants who had engaged in practice had significant increases in activation in the anterior cingulate cortex (ACC), the left inferior parietal lobule (IPL), the left dorsolateral prefrontal cortex (DLPFC) and the precuneus regions during the NF-RST. By contrast, a control group, which did not practice, showed no significant increases in these regions. Results suggest that practice on conflict tasks in elderly individuals activated regions related to conflict perceiving and attention switching regions as well as attention-maintenance regions thereby improving performance on tasks requiring a high degree of attention control of working memory. Copyright © 2012 Elsevier B.V. All rights reserved.
Ratwani, Raj M; Andrews, Alyssa E; McCurry, Malcolm; Trafton, J. G; Peterson, Matthew S
.... In addition, eye track data suggest that participants were more accurate at returning to where they left off, suggesting that they were able to maintain a spatial representation of the task and use this information to resume more quickly.
It has recently been reported that selective REM sleep deprivation (REMD) in college students results in memory impairment of the application of a set of rules in a logic task, but not recall of a paired associate task. The present experiments were designed to examine the effects of Total Sleep Deprivation (TSD) and (REMD) following acquisition of a pure motor task, the pursuit rotor. In Experiment 1, subjects (N = 90) were exposed to TSD for one of several nights following training. Results showed that TSD on the same night as training resulted in poorer performance on retest one week later. In Experiment 2, subjects (N = 42) were exposed to various kinds of sleep deprivation on the night of task acquisition. One group was subjected to REMD. Other groups included a non-REM awakening control group (NREMA), a TSD group, a normally rested Control group and a group allowed the first 4 h of sleep in the night before being subjected to TSD (LH - TSD) for the rest of the night. Results showed the REMD and Control groups to have excellent memory for this task while the TSD and LH - TSD subjects had significantly poorer memory for the task. The NREMA group showed a slight, but not significant deficit. It was concluded that Stage 2 sleep, rather than REM sleep was the important stage of sleep for efficient memory processing of the pursuit rotor task.
Poch, Claudia; Capilla, Almudena; Hinojosa, José Antonio; Campo, Pablo
Working Memory (WM) maintains flexible representations. Retrospective cueing studies indicate that selective attention can be directed to memory representations in WM improving performance. While most of the work has explored the neural substrates of orienting attention based on a spatial retro-cue, behavioral studies show that a feature other than location can also improve WM performance. In the present work we explored the oscillatory underpinnings of orienting attention to a relevant representation held in WM guided by a feature value. We recorded EEG data in a group of 36 healthy human subjects (20 females) performing a WM task in which they had to memorize the orientation of four rectangles of different colors. After a maintenance period, a cue was presented indicating the color of the relevant item. We showed that directing attention to a memory item based on its color resulted in a modulation of posterior alpha activity, which appears as more desynchronization in the contralateral than in the ipsilateral hemisphere. Alpha lateralization is considered a neurophysiological marker of external and internal spatial attention. We propose that current findings support the idea that selection of a memory item based on a non-location feature could be accomplished by a spatial attentional mechanism. Moreover, using a centrally presented color retro-cue allowed us to surpass the confounds inherent to the use of spatial retro-cues, supporting that the observed lateralized alpha results from an endogenous attentional mechanism. Copyright © 2017 Elsevier Ltd. All rights reserved.
Muthukrishnan, Suriya-Prakash; Ahuja, Navdeep; Mehta, Nalin; Sharma, Ratna
Humans have limited capacity of processing just up to 4 integrated items of information in the working memory. Thus, it is inevitable to commit more errors when challenged with high memory loads. However, the neural mechanisms that determine the accuracy of response at high memory loads still remain unclear. High temporal resolution of Electroencephalography (EEG) technique makes it the best tool to resolve the temporal dynamics of brain networks. EEG-defined microstate is the quasi-stable scalp electrical potential topography that represents the momentary functional state of brain. Thus, it has been possible to assess the information processing currently performed by the brain using EEG microstate analysis. We hypothesize that the EEG microstate preceding the trial could determine its outcome in a visuospatial working memory (VSWM) task. Twenty-four healthy participants performed a high memory load VSWM task, while their brain activity was recorded using EEG. Four microstate maps were found to represent the functional brain state prior to the trials in the VSWM task. One pre-trial microstate map was found to determine the accuracy of subsequent behavioural response. The intracranial generators of the pre-trial microstate map that determined the response accuracy were localized to the visuospatial processing areas at bilateral occipital, right temporal and limbic cortices. Our results imply that the behavioural outcome in a VSWM task could be determined by the intensity of activation of memory representations in the visuospatial processing brain regions prior to the trial. Copyright © 2016 Elsevier B.V. All rights reserved.
Landmann, Nina; Kuhn, Marion; Maier, Jonathan-Gabriel; Feige, Bernd; Spiegelhalder, Kai; Riemann, Dieter; Nissen, Christoph
Sleep after learning promotes the quantitative strengthening of new memories. Less is known about the impact of sleep on the qualitative reorganization of memory content. This study tested the hypothesis that sleep facilitates both memory strengthening and reorganization as indexed by a verbal creativity task. Sixty healthy university students (30 female, 30 male, 20-30 years) were investigated in a randomized, controlled parallel-group study with three experimental groups (sleep, sleep deprivation, daytime wakefulness). At baseline, 60 items of the Compound Remote Associate (CRA) task were presented. At retest after the experimental conditions, the same items were presented again together with 20 new control items to disentangle off-line incubation from online performance effects. Sleep significantly strengthened formerly encoded memories in comparison to both wake conditions (improvement in speed of correctly resolved items). Offline reorganization was not enhanced following sleep, but was enhanced following sleep-deprivation in comparison to sleep and daytime wakefulness (solution time of previously incubated, newly solved items). Online performance did not differ between the groups (solution time of new control items). The results support the notion that sleep promotes the strengthening, but not the reorganization, of newly encoded memory traces in a verbal creativity task. Future studies are needed to further determine the impact of sleep on different types of memory reorganization, such as associative thinking, creativity and emotional memory processing, and potential clinical translations, such as the augmentation of psychotherapy through sleep interventions. © 2016 Associated Professional Sleep Societies, LLC.
Bertrand, Julie Marilyne; Moulin, Chris John Anthony; Souchay, Céline
Our objective was to explore metamemory in short-term memory across the lifespan. Five age groups participated in this study: 3 groups of children (4-13 years old), and younger and older adults. We used a three-phase task: prediction-span-postdiction. For prediction and postdiction phases, participants reported with a Yes/No response if they could recall in order a series of images. For the span task, they had to actually recall such series. From 4 years old, children have some ability to monitor their short-term memory and are able to adjust their prediction after experiencing the task. However, accuracy still improves significantly until adolescence. Although the older adults had a lower span, they were as accurate as young adults in their evaluation, suggesting that metamemory is unimpaired for short-term memory tasks in older adults. •We investigate metamemory for short-term memory tasks across the lifespan. •We find younger children cannot accurately predict their span length. •Older adults are accurate in predicting their span length. •People's metamemory accuracy was related to their short-term memory span.
Klados, Manousos A; Simos, Panagiotis; Micheloyannis, Sifis; Margulies, Daniel; Bamidis, Panagiotis D
There have been several attempts to account for the impact of Mathematical Anxiety (MA) on brain activity with variable results. The present study examines the effects of MA on ERP amplitude during performance of simple arithmetic calculations and working memory tasks. Data were obtained from 32 university students as they solved four types of arithmetic problems (one- and two-digit addition and multiplication) and a working memory task comprised of three levels of difficulty (1, 2, and 3-back task). Compared to the Low-MA group, High-MA individuals demonstrated reduced ERP amplitude at frontocentral (between 180-320 ms) and centroparietal locations (between 380-420 ms). These effects were independent of task difficulty/complexity, individual performance, and general state/trait anxiety levels. Results support the hypothesis that higher levels of self-reported MA are associated with lower cortical activation during the early stages of the processing of numeric stimuli in the context of cognitive tasks.
Kretschmer-Trendowicz, A; Schnitzspahn, K M; Reuter, L; Altgassen, M
Research on children's prospective memory (PM) shows an increase of performance across childhood and provides first evidence that encoding strategies such as episodic future thinking (EFT; i.e., engaging in a vivid prospection of oneself performing future tasks) may improve performance. The present study aimed at testing whether the beneficial effects of EFT extend from typical lab-based tasks to more complex tasks with real life demands. Further, it was tested whether children's ability to project themselves into different perspectives (i.e., self-projection) moderates the effects of EFT encoding on PM. Overall, 56 children (mean age: M = 10.73 years) were included in this study who were randomly assigned to either an EFT or control condition. Children participated in a 'sightseeing tour' (ongoing activity) inside the lab with various socially relevant and neutral PM tasks embedded. Results showed significantly higher PM performance in the EFT compared to the control group. There was no difference between neutral and social PM tasks and no interaction between type of PM tasks with encoding condition. Further, self-projection did not moderate the effects of EFT encoding on PM. Results suggest that EFT is an effective strategy to improve children's everyday PM. These beneficial effects seem to occur independent from children's general ability to change perspectives and for different types of PM tasks.
Boselie, Jantine J L M; Vancleef, Linda M G; Peters, Madelon L
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
Nakamura, Katsuki; Koba, Reiko; Miwa, Miki; Yamaguchi, Chieko; Suzuki, Hiromi; Takemoto, Atsushi
Learning and memory processes are similarly organized in humans and monkeys; therefore, monkeys can be ideal models for analyzing human aging processes and neurodegenerative diseases such as Alzheimer's disease. With the development of novel gene modification methods, common marmosets ( Callithrix jacchus ) have been suggested as an animal model for neurodegenerative diseases. Furthermore, the common marmoset's lifespan is relatively short, which makes it a practical animal model for aging. Working memory deficits are a prominent symptom of both dementia and aging, but no data are currently available for visual working memory in common marmosets. The delayed matching-to-sample task is a powerful tool for evaluating visual working memory in humans and monkeys; therefore, we developed a novel procedure for training common marmosets in such a task. Using visual discrimination and reversal tasks to direct the marmosets' attention to the physical properties of visual stimuli, we successfully trained 11 out of 13 marmosets in the initial stage of the delayed matching-to-sample task and provided the first available data on visual working memory in common marmosets. We found that the marmosets required many trials to initially learn the task (median: 1316 trials), but once the task was learned, the animals needed fewer trials to learn the task with novel stimuli (476 trials or fewer, with the exception of one marmoset). The marmosets could retain visual information for up to 16 s. Our novel training procedure could enable us to use the common marmoset as a useful non-human primate model for studying visual working memory deficits in neurodegenerative diseases and aging.
Huff, Mark J; Yates, Tyler J; Balota, David A
Recently, we have shown that two types of initial testing (recall of a list or guessing of critical items repeated over 12 study/test cycles) improved final recognition of related and unrelated word lists relative to restudy. These benefits were eliminated, however, when test instructions were manipulated within subjects and presented after study of each list, procedures designed to minimise expectancy of a specific type of upcoming test [Huff, Balota, & Hutchison, 2016. The costs and benefits of testing and guessing on recognition memory. Journal of Experimental Psychology: Learning, Memory, and Cognition, 42, 1559-1572. doi: 10.1037/xlm0000269 ], suggesting that testing and guessing effects may be influenced by encoding strategies specific for the type of upcoming task. We follow-up these experiments by examining test-expectancy processes in guessing and testing. Testing and guessing benefits over restudy were not found when test instructions were presented either after (Experiment 1) or before (Experiment 2) a single study/task cycle was completed, nor were benefits found when instructions were presented before study/task cycles and the task was repeated three times (Experiment 3). Testing and guessing benefits emerged only when instructions were presented before a study/task cycle and the task was repeated six times (Experiments 4A and 4B). These experiments demonstrate that initial testing and guessing can produce memory benefits in recognition, but only following substantial task repetitions which likely promote task-expectancy processes.
Full Text Available Memory is prone to illusions. When people are presented with lists of words associated with a non-presented critical lure, they produce a high level of false recognitions (false memories for non-presented related stimuli indistinguishable, at the explicit level, from presented words (DRM paradigm. We assessed whether true and false DRM memories can be distinguished at the implicit level by using the autobiographical IAT (aIAT, a novel method based on indirect measures that permits to detect true autobiographical events encoded in the respondent's mind/brain. In our experiment, after a DRM task participants performed two aIATs: the first aimed at testing implicit memory for presented words (true-memories aIAT and the second aimed at evaluating implicit memory for critical lures (false-memories aIAT. Specifically, the two aIATs assessed the association of presented words and critical lures with the logical dimension true. Results showed that the aIAT detected a greater association of presented words than critical lures with the logical dimension true. This result indicates that although true and false DRM memories are indistinguishable at the explicit level a different association of the true and false DRM memories with the logical dimension true can be detected at the implicit level, and suggests that the aIAT may be a sensitive instrument to detect differences between true and false DRM memories.
Marini, Maddalena; Agosta, Sara; Mazzoni, Giuliana; Barba, Gianfranco Dalla; Sartori, Giuseppe
Memory is prone to illusions. When people are presented with lists of words associated with a non-presented critical lure, they produce a high level of false recognitions (false memories) for non-presented related stimuli indistinguishable, at the explicit level, from presented words (DRM paradigm). We assessed whether true and false DRM memories can be distinguished at the implicit level by using the autobiographical IAT (aIAT), a novel method based on indirect measures that permits to detect true autobiographical events encoded in the respondent's mind/brain. In our experiment, after a DRM task participants performed two aIATs: the first aimed at testing implicit memory for presented words (true-memories aIAT) and the second aimed at evaluating implicit memory for critical lures (false-memories aIAT). Specifically, the two aIATs assessed the association of presented words and critical lures with the logical dimension "true." Results showed that the aIAT detected a greater association of presented words than critical lures with the logical dimension "true." This result indicates that although true and false DRM memories are indistinguishable at the explicit level a different association of the true and false DRM memories with the logical dimension "true" can be detected at the implicit level, and suggests that the aIAT may be a sensitive instrument to detect differences between true and false DRM memories.
Amir Kassim, Azlina; Rehman, Rehan; Price, Jessica M
Previous research has shown that auditory recognition memory is poorer compared to visual and cross-modal (visual and auditory) recognition memory. The effect of repetition on memory has been robust in showing improved performance. It is not clear, however, how auditory recognition memory compares to visual and cross-modal recognition memory following repetition. Participants performed a recognition memory task, making old/new discriminations to new stimuli, stimuli repeated for the first time after 4-7 intervening items (R1), or repeated for the second time after 36-39 intervening items (R2). Depending on the condition, participants were either exposed to visual stimuli (2D line drawings), auditory stimuli (spoken words), or cross-modal stimuli (pairs of images and associated spoken words). Results showed that unlike participants in the visual and cross-modal conditions, participants in the auditory recognition did not show improvements in performance on R2 trials compared to R1 trials. These findings have implications for pedagogical techniques in education, as well as for interventions and exercises aimed at boosting memory performance. Copyright © 2018 Elsevier B.V. All rights reserved.
Choi, Sangsook; Lotto, Andrew; Lewis, Dawna; Hoover, Brenda; Stelmachowicz, Patricia
Purpose: This study investigated an account of limited short-term memory capacity for children's speech perception in noise using a dual-task paradigm. Method: Sixty-four normal-hearing children (7-14 years of age) participated in this study. Dual tasks were repeating monosyllabic words presented in noise at 8 dB signal-to-noise ratio and…
Pottage, Claire L; Schaefer, Alexandre
The emotional enhancement of memory is often thought to be determined by attention. However, recent evidence using divided attention paradigms suggests that attention does not play a significant role in the formation of memories for aversive pictures. We report a study that investigated this question using a paradigm in which participants had to encode lists of randomly intermixed negative and neutral pictures under conditions of full attention and divided attention followed by a free recall test. Attention was divided by a highly demanding concurrent task tapping visual processing resources. Results showed that the advantage in recall for aversive pictures was still present in the DA condition. However, mediation analyses also revealed that concurrent task performance significantly mediated the emotional enhancement of memory under divided attention. This finding suggests that visual attentional processes play a significant role in the formation of emotional memories. PsycINFO Database Record (c) 2012 APA, all rights reserved
Vawter, M P; De Wied, D; Van Ree, J M
The hole board search task (HBST) measures long-term and short-term memory, operationally defined as reference memory and working memory. The HBST is an open-field spatial learning test. Previously, we have shown that desglycinamide(Arg8) vasopressin (DGAVP) modulated reference memory, working memory, spatial sequence memory, and learning in the HBST in a dose-dependent manner (Vawter MP, Van Ree JM. Effects of des-glycinamide-sup-9-(arginine-sup-8) vasopressin upon spatial memory in the hole-board search task. Psychobiology 1995; 23: 45-51). To examine the potential active site of the DGAVP molecule, the fragment of the vasopressin amino acid sequence, [pGlu4,Cyt6]AVP-(4-8) (AVP-(4-8)), was administered 1 h prior to training in the HBST. Three groups received either 0, 0.3 microgram, or 1 microgram AVP-(4-8). A repeated measures MANOVA showed the AVP-(4-8) pretreatment factor to be significant (P = 0.048) on the reference memory measure, but not the working memory or learning measures. Interactions between peptide x sessions for reference memory (P = 0.015), working memory (P = 0.003) and learning (P = 0.010) indicated differences in improvement over sessions between placebo- and peptide-treated groups. Post hoc comparisons revealed that the AVP-(4-8) fragment in a dose of 0.3 microgram increased reference memory on the fourth, fifth and sixth acquisition sessions compared with placebo or 1 microgram AVP-(4-8) pretreated groups. Working memory and errors were significantly lowered by 0.3 microgram AVP-(4-8) on the first acquisition session when compared with placebo pretreatment. Thus, AVP-(4-8) improves long-term and short-term memory scores in the HBST, similar to previous results with DGAVP. However, AVP-(4-8) appears twice as potent than DGAVP in improving long-term memory scores in the HBST. The data suggest that the memory modulating property of DGAVP is contained within the amino acid sequence of the AVP-(4-8) peptide.
Di, Xin; Huang, Jia; Biswal, Bharat B
Understanding functional connectivity of the amygdala with other brain regions, especially task modulated connectivity, is a critical step toward understanding the role of the amygdala in emotional processes and the interactions between emotion and cognition. The present study performed coordinate-based meta-analysis on studies of task modulated connectivity of the amygdala which used psychophysiological interaction (PPI) analysis. We first analyzed 49 PPI studies on different types of tasks using activation likelihood estimation (ALE) meta-analysis. Widespread cortical and subcortical regions showed consistent task modulated connectivity with the amygdala, including the medial frontal cortex, bilateral insula, anterior cingulate, fusiform gyrus, parahippocampal gyrus, thalamus, and basal ganglia. These regions were in general overlapped with those showed coactivations with the amygdala, suggesting that these regions and amygdala are not only activated together, but also show different levels of interactions during tasks. Further analyses with subsets of PPI studies revealed task specific functional connectivities with the amygdala that were modulated by fear processing, face processing, and emotion regulation. These results suggest a dynamic modulation of connectivity upon task demands, and provide new insights on the functions of the amygdala in different affective and cognitive processes. The meta-analytic approach on PPI studies may offer a framework toward systematical examinations of task modulated connectivity.
da Silva, Ronaldo Luis; Labrecque, David; Caromano, Fátima Aparecida; Higgins, Johanne; Frak, Victor
Manual action verbs modulate the right-hand grip force in right-handed subjects. However, to our knowledge, no studies demonstrate the ability to accomplish this modulation during bimanual tasks nor describe their effect on left-hand behavior in unimanual and bimanual tasks. Using load cells and word playlists, we evaluated the occurrence of grip force modulation by manual action verbs in unimanual and symmetrical bimanual tasks across the three auditory processing phases. We found a significant grip force increase for all conditions compared to baseline, indicating the occurrence of modulation. When compared to each other, the grip force variation from baseline for the three phases of both hands in the symmetrical bimanual task was not different from the right-hand in the unimanual task. The left-hand grip force showed a lower amplitude for auditory phases 1 and 2 when compared to the other conditions. The right-hand grip force modulation became significant from baseline at 220 ms after the word onset in the unimanual task. This moment occurred earlier for both hands in bimanual task (160 ms for the right-hand and 180 for the left-hand). It occurred later for the left-hand in unimanual task (320 ms). We discuss the hypothesis that Broca's area and Broca's homologue area likely control the left-hand modulation in a unilateral or a bilateral fashion. These results provide new evidence for understanding the linguistic function processing in both hemispheres.
Ronaldo Luis da Silva
Full Text Available Manual action verbs modulate the right-hand grip force in right-handed subjects. However, to our knowledge, no studies demonstrate the ability to accomplish this modulation during bimanual tasks nor describe their effect on left-hand behavior in unimanual and bimanual tasks. Using load cells and word playlists, we evaluated the occurrence of grip force modulation by manual action verbs in unimanual and symmetrical bimanual tasks across the three auditory processing phases. We found a significant grip force increase for all conditions compared to baseline, indicating the occurrence of modulation. When compared to each other, the grip force variation from baseline for the three phases of both hands in the symmetrical bimanual task was not different from the right-hand in the unimanual task. The left-hand grip force showed a lower amplitude for auditory phases 1 and 2 when compared to the other conditions. The right-hand grip force modulation became significant from baseline at 220 ms after the word onset in the unimanual task. This moment occurred earlier for both hands in bimanual task (160 ms for the right-hand and 180 for the left-hand. It occurred later for the left-hand in unimanual task (320 ms. We discuss the hypothesis that Broca's area and Broca's homologue area likely control the left-hand modulation in a unilateral or a bilateral fashion. These results provide new evidence for understanding the linguistic function processing in both hemispheres.
Landmann, Nina; Kuhn, Marion; Maier, Jonathan-Gabriel; Feige, Bernd; Spiegelhalder, Kai; Riemann, Dieter; Nissen, Christoph
Study Objectives: Sleep after learning promotes the quantitative strengthening of new memories. Less is known about the impact of sleep on the qualitative reorganization of memory content. This study tested the hypothesis that sleep facilitates both memory strengthening and reorganization as indexed by a verbal creativity task. Methods: Sixty healthy university students (30 female, 30 male, 20–30 years) were investigated in a randomized, controlled parallel-group study with three experimental groups (sleep, sleep deprivation, daytime wakefulness). At baseline, 60 items of the Compound Remote Associate (CRA) task were presented. At retest after the experimental conditions, the same items were presented again together with 20 new control items to disentangle off-line incubation from online performance effects. Results: Sleep significantly strengthened formerly encoded memories in comparison to both wake conditions (improvement in speed of correctly resolved items). Offline reorganization was not enhanced following sleep, but was enhanced following sleep-deprivation in comparison to sleep and daytime wakefulness (solution time of previously incubated, newly solved items). Online performance did not differ between the groups (solution time of new control items). Conclusions: The results support the notion that sleep promotes the strengthening, but not the reorganization, of newly encoded memory traces in a verbal creativity task. Future studies are needed to further determine the impact of sleep on different types of memory reorganization, such as associative thinking, creativity and emotional memory processing, and potential clinical translations, such as the augmentation of psychotherapy through sleep interventions. Citation: Landmann N, Kuhn M, Maier JG, Feige B, Spiegelhalder K, Riemann D, Nissen C. Sleep strengthens but does not reorganize memory traces in a verbal creativity task. SLEEP 2016;39(3):705–713. PMID:26518596
Brum, Paula Schimidt; Borella, Erika; Carretti, Barbara; Guidotti, Elena; Yassuda, Mônica Sanches
The Categorization Working Memory Span Task (CWMS task) is a complex working memory (WM) span test that has been used previously to assess age and individual differences in WM as well as the relationship between WM and complex aspects of cognition such as listening comprehension. Two alternate versions of the task have been developed to be used as outcome variables in WM training protocol, which mirrors the task involved in the CWMS task. (1) To translate and adapt the CWMS task for Brazilian Portuguese; (2) to test the equivalence of its 2 alternate versions; (3) to examine temporal stability; (4) to examine the influence of age and schooling on CWMS task; (5) to establish its relationship with other tests of WM. Eighty-one older adults completed version A, and 86 completed version B of the CWMS task. After 6 months, a subsample (n = 85) completed the same version of the task. Versions A and B of the task generated comparable scores. Both versions had adequate temporal stability, which was higher for the CWMS total recall, which is the classical variable in this task to represent WM performance, when compared to the other variables generated by the test. The CWMS task variables were moderately correlated with schooling and other cognitive tests (Mini Mental State Examination, Letter-Number Sequencing, Spatial Span Backward, Digit Span Forward). The 2 versions of the CWMS task were equivalent and stable temporally. The task was influenced by schooling and global cognition. Copyright © 2017 John Wiley & Sons, Ltd.
Full Text Available This paper presents the MnemoCity task, which is a 3D application that introduces the user into a totally 3D virtual environment to evaluate spatial short-term memory. A study has been carried out to validate the MnemoCity task for the assessment of spatial short-term memory in children, by comparing the children's performance in the developed task with current approaches. A total of 160 children participated in the study. The task incorporates two types of interaction: one based on standard interaction and another one based on natural interaction involving physical movement by the user. There were no statistically significant differences in the results of the task using the two types of interaction. Furthermore, statistically significant differences were not found in relation to gender. The correlations between scores were obtained using the MnemoCity task and a traditional procedure for assessing spatial short-term memory. Those results revealed that the type of interaction used did not affect the performance of children in the MnemoCity task.
Sörqvist, Patrik; Stenfelt, Stefan; Rönnberg, Jerker
Two fundamental research questions have driven attention research in the past: One concerns whether selection of relevant information among competing, irrelevant, information takes place at an early or at a late processing stage; the other concerns whether the capacity of attention is limited by a central, domain-general pool of resources or by independent, modality-specific pools. In this article, we contribute to these debates by showing that the auditory-evoked brainstem response (an early stage of auditory processing) to task-irrelevant sound decreases as a function of central working memory load (manipulated with a visual-verbal version of the n-back task). Furthermore, individual differences in central/domain-general working memory capacity modulated the magnitude of the auditory-evoked brainstem response, but only in the high working memory load condition. The results support a unified view of attention whereby the capacity of a late/central mechanism (working memory) modulates early precortical sensory processing.
Glienke, Katharina; Piefke, Martina
Successful execution of intentions, but also the failure to recall are common phenomena in everyday life. The planning, retention, and realization of intentions are often framed as the scientific concept of prospective memory. The current study aimed to examine the influence of acute stress on key dimensions of complex "real life" prospective memory. To this end, we applied a prospective memory task that involved the planning, retention, and performance of intentions during a fictional holiday week. Forty healthy males participated in the study. Half of the subjects were stressed with the Socially Evaluated Cold Pressor Test (SECPT) before the planning of intentions, and the other half of the participants underwent a control procedure at the same time. Salivary cortisol was used to measure the effectiveness of the SECPT stress induction. Stressed participants did not differ from controls in planning accuracy. However, when we compared stressed participants with controls during prospective memory retrieval, we found statistically significant differences in PM across the performance phase. Participants treated with the SECPT procedure before the planning phase showed improved prospective memory retrieval over time, while performance of controls declined. Particularly, there was a significant difference between the stress and control group for the last two days of the holiday week. Interestingly, control participants showed significantly better performance for early than later learned items, which could be an indicator of a primacy effect. This differential effect of stress on performance was also found in time- and event-dependent prospective memory. Our results demonstrate for the first time, that acute stress induced before the planning phase may improve prospective memory over the time course of the performance phase in time- and event-dependent prospective memory. Our data thus indicate that prospective memory can be enhanced by acute stress. Copyright © 2016
Ward, Heather; Shum, David; McKinlay, Lynne; Baker-Tweney, Simone; Wallace, Geoff
This study investigated the development of prospective memory using tasks based on the prefrontal-lobe model. Three groups each of 30 children, adolescents, and young adults were compared on prospective-memory performance using ongoing tasks with two levels of cognitive demand (low and high), and two levels of importance (unstressed and stressed) of remembering prospective cues. The Self-Ordered Pointing Task (SOPT), Stroop Color Word Interference Test, and Tower of London were also used to assess relationships between prospective memory and prefrontal-lobe functions. The children remembered fewer prospective cues than either the adolescents or adults, but the adolescents and adults remembered equally well. This trend increased significantly as the cognitive demand of the ongoing tasks increased. However, stressing or not stressing the importance of remembering made no difference to prospective-memory performance. Performance on the SOPT and Stroop Colour Word Interference predicted performance on the high- but not on the low-demand condition. These findings implicate the maturation of the brain's prefrontal region in the development of prospective memory.
Goodman, Jarid; Ressler, Reed L; Packard, Mark G
The present experiments investigated the involvement of N-methyl-d-aspartate (NMDA) receptors of the dorsolateral striatum (DLS) in consolidation of extinction in a habit memory task. Adult male Long-Evans rats were initially trained in a food-reinforced response learning version of a plus-maze task and were subsequently given extinction training in which the food was removed from the maze. In experiment 1, immediately after the first day of extinction training, rats received bilateral intra-DLS injections of the NMDA receptor antagonist 2-amino-5-phosphonopentanoic acid (AP5; 2µg/side) or physiological saline. In experiment 2, immediately following the first day of extinction training, animals were given intra-DLS injections of NMDA receptor partial agonist d-cycloserine (DCS; 10 or 20µg/side) or saline. In both experiments, the number of perseverative trials (a trial in which a rat made the same previously reinforced body-turn response) and latency to reach the previously correct food well were used as measures of extinction behavior. Results indicated that post-training intra-DLS injections of AP5 impaired extinction. In contrast, post-training intra-DLS infusions of DCS (20µg) enhanced extinction. Intra-DLS administration of AP5 or DCS given two hours after extinction training did not influence extinction of response learning, indicating that immediate post-training administration of AP5 and DCS specifically influenced consolidation of the extinction memory. The present results indicate a critical role for DLS NMDA receptors in modulating extinction of habit memory and may be relevant to developing therapeutic approaches to combat the maladaptive habits observed in human psychopathologies in which DLS-dependent memory has been implicated (e.g. drug addiction and relapse and obsessive compulsive disorder). Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.
Schwabe, Lars; Tegenthoff, Martin; Höffken, Oliver; Wolf, Oliver T
Accumulating evidence suggests that stress may orchestrate the engagement of multiple memory systems in the brain. In particular, stress is thought to favor dorsal striatum-dependent procedural over hippocampus-dependent declarative memory. However, the neuroendocrine mechanisms underlying these modulatory effects of stress remain elusive, especially in humans. Here, we targeted the role of the mineralocorticoid receptor (MR) in the stress-induced modulation of dorsal striatal and hippocampal memory systems in the human brain using a combination of event-related functional magnetic resonance imaging and pharmacologic blockade of the MR. Eighty healthy participants received the MR antagonist spironolactone (300 mg) or a placebo and underwent a stressor or control manipulation before they performed, in the scanner, a classification task that can be supported by the hippocampus and the dorsal striatum. Stress after placebo did not affect learning performance but reduced explicit task knowledge and led to a relative increase in the use of more procedural learning strategies. At the neural level, stress promoted striatum-based learning at the expense of hippocampus-based learning. Functional connectivity analyses showed that this shift was associated with altered coupling of the amygdala with the hippocampus and dorsal striatum. Mineralocorticoid receptor blockade before stress prevented the stress-induced shift toward dorsal striatal procedural learning, same as the stress-induced alterations of amygdala connectivity with hippocampus and dorsal striatum, but resulted in significantly impaired performance. Our findings indicate that the stress-induced shift from hippocampal to dorsal striatal memory systems is mediated by the amygdala, required to preserve performance after stress, and dependent on the MR. © 2013 Society of Biological Psychiatry.
Piai, Vitória; Roelofs, Ardi
Researchers have found no agreement on whether dual-task interference in language performance, such as dual-task interference from tone discrimination on picture naming, reflects passive queuing or active scheduling of processes for each task. According to a passive-queuing account, while a central response-selection bottleneck is occupied by the tone discrimination task, picture naming is held in a passive queue until the bottleneck is freed. In contrast, according to an active-scheduling account, participants determine the order in which the tasks proceed, monitor progress on the tasks, suspend picture naming and hold it in working memory, and determine when to resume picture naming. Here, we report a study that assessed the relative merits of the queuing and scheduling accounts by examining whether the magnitude of dual-task interference in picture naming is associated with individual differences in the capacity of monitoring and updating of working memory representations, as assessed by the operation-span task. We observed that the updating/monitoring ability correlated with the speed of picture naming and with the magnitude of the interference from tone discrimination on picture naming. These results lend support to the active-scheduling account of dual-task interference in picture naming. Copyright © 2013 Elsevier B.V. All rights reserved.
Kimchi, Ruth; Pirkner, Yossef
Perception of object continuity depends on establishing correspondence between objects viewed across disruptions in visual information. The role of spatiotemporal information in guiding object continuity is well documented; the role of surface features, however, is controversial. Some researchers have shown an object-specific preview benefit (OSPB)-a standard index of object continuity-only when correspondence could be based on an object's spatiotemporal information, whereas others have found color-based OSPB, suggesting that surface features can also guide object continuity. This study shows that surface feature-based OSPB is dependent on the task memory demands. When the task involved letters and matching just one target letter to the preview ones, no color congruency effect was found under spatiotemporal discontinuity and spatiotemporal ambiguity (Experiments 1-3), indicating that the absence of feature-based OSPB cannot be accounted for by salient spatiotemporal discontinuity. When the task involved complex shapes and matching two target shapes to the preview ones, color-based OSPB was obtained. Critically, however, when a visual working memory task was performed concurrently with the matching task, the presence of a nonspatial (but not a spatial) working memory load eliminated the color-based OSPB (Experiments 4 and 5). These results suggest that the surface feature congruency effects that are observed in the object-reviewing paradigm (with the matching task) reflect memory-based strategies that participants use to solve a memory-demanding task; therefore, they are not reliable measures of online object continuity and cannot be taken as evidence for the role of surface features in establishing object correspondence.
Lilienthal, Lindsey; Hale, Sandra; Myerson, Joel
The present experiments examined the effects of environmental support on participants’ ability to rehearse locations and its role in the effects of secondary tasks on memory span. In Experiment 1, the duration of inter-item intervals and the presence of environmental support for visuospatial rehearsal (i.e., the array of possible memory locations) during the inter-item intervals were both manipulated across four tasks. When support was provided, memory spans increased as the inter-item interval durations increased, consistent with the hypothesis that environmental support facilitates rehearsal. In contrast, when environmental support was not provided, spans decreased as the duration of the inter-item intervals increased, consistent with the hypothesis that visuospatial memory representations decay when rehearsal is impeded. In Experiment 2, the ratio of inter-item interval duration to inter-trial interval duration was kept the same on all four tasks in order to hold temporal distinctiveness constant, yet forgetting was still observed in the absence of environmental support, consistent with the decay hypothesis. In Experiment 3, the effects of impeding rehearsal were compared to the effects of verbal and visuospatial secondary processing tasks. Forgetting of locations was greater when presentation of to-be-remembered locations alternated with performance of a secondary task than when rehearsal was impeded by the absence of environmental support. The greatest forgetting occurred when a secondary task required processing visuospatial information, suggesting that in addition to decay, both domain-specific and domain-general effects contribute to forgetting on visuospatial working memory tasks. PMID:24874509
Zanin, Karina A; Patti, Camilla L; Sanday, Leandro; Fernandes-Santos, Luciano; Oliveira, Larissa C; Poyares, Dalva; Tufik, Sergio; Frussa-Filho, Roberto
Zolpidem (Zolp), a hypnotic drug prescribed to treat insomnia, may have negative effects on memory, but reports are inconsistent. We examined the effects of acute doses of Zolp (2, 5, or 10 mg/kg, i.p.) on memory formation (learning, consolidation, and retrieval) using the plus-maze discriminative avoidance task. Mice were acutely treated with Zolp 30 min before training or testing. In addition, the effects of Zolp and midazolam (Mid; a classic benzodiazepine) on consolidation at different time points were examined. The possible role of state dependency was investigated using combined pre-training and pre-test treatments. Zolp produced a dose-dependent sedative effect, without modifying anxiety-like behavior. The pre-training administration of 5 or 10 mg/kg resulted in retention deficits. When administered immediately after training or before testing, memory was preserved. Zolp post-training administration (2 or 3 h) impaired subsequent memory. There was no participation of state dependency phenomenon in the amnestic effects of Zolp. Similar to Zolp, Mid impaired memory consolidation when administered 1 h after training. Amnestic effects occurred when Zolp was administered either before or 2-3 h after training. These memory deficits are not related to state dependency. Moreover, Zolp did not impair memory retrieval. Notably, the memory-impairing effects of Zolp are similar to those of Mid, with the exception of the time point at which the drug can modify consolidation. Finally, the memory effects were unrelated to sedation or anxiolysis.
Atance, Cristina M; Sommerville, Jessica A
A total of 48 preschoolers (ages 3, 4, and 5) received four tasks modelled after prior work designed to assess the development of "episodic foresight". For each task, children encountered a problem in one room and, after a brief delay, were given the opportunity in a second room to select an item to solve the problem. Importantly, after selecting an item, children were queried about their memory for the problem. Age-related changes were found both in children's ability to select the correct item and their ability to remember the problem. However, when we controlled for children's memory for the problem, there were no longer significant age-related changes on the item choice measure. These findings suggest that age-related changes in children's performance on these tasks are driven by improvements in children's memory versus improvements in children's future-oriented thinking or "foresight" per se. Our results have important implications for how best to structure tasks to measure children's episodic foresight, and also for the relative role of memory in this task and in episodic foresight more broadly.
Barban, Francesco; Carlesimo, Giovanni Augusto; Macaluso, Emiliano; Caltagirone, Carlo; Costa, Alberto
Recent studies have suggested that medial (medBA10) and lateral (latBA10) portions of the Brodmann area 10 subserve respectively stimulus-oriented (SO) and stimulus-independent (SI) attending during prospective memory (PM) tasks. We investigated this dissociation by manipulating the saliency (SO) and the memory load (SI) of PM cues. Sixteen healthy subjects participated to a functional imaging protocol with a 2×2×2 experimental design, including the factors: task (ongoing target vs. PM cue), Saliency (high vs. low; with targets/cues either embedded or standing out from distracters), and memory load (high vs. low; with 1 or 4 possible PM targets). We localized the medBA10 and latBA10 by means of a localizer task. In medBA10 we found a significant main effects of high Saliency and low memory load; whereas in the left latBA10, we found a significant task×load interaction, with maximal activation for PM cues presented in the high load condition. These results are in agreement with the gateway hypothesis: during a PM task medBA10 biases attention toward external salient stimuli, SO attending, while latBA10 biases attention toward internal mnemonic representations, SI attending. Additional whole-brain analyses highlighted activation of other areas besides BA10, consistent with recent proposals that emphasise the role of distributed networks during PM performance. © 2013 Published by Elsevier Ltd.
Full Text Available Our study explores inhibitory control across a range of widely recognised memory and behavioural tasks. Eighty-seven never-depressed participants completed a series of tasks designed to measure inhibitory control in memory and behaviour. Specifically, a variant of the selective retrieval-practice and the Think/No-Think tasks were employed as measures of memory inhibition. The Stroop-Colour Naming and the Go/No-Go tasks were used as measures of behavioural inhibition. Participants completed all 4 tasks. Task presentation order was counterbalanced across 3 separate testing sessions for each participant. Standard inhibitory forgetting effects emerged on both memory tasks but the extent of forgetting across these tasks was not correlated. Furthermore, there was no relationship between memory inhibition tasks and either of the main behavioural inhibition measures. At a time when cognitive inhibition continues to gain acceptance as an explanatory mechanism, our study raises fundamental questions about what we actually know about inhibition and how it is affected by the processing demands of particular inhibitory tasks.
Noreen, Saima; MacLeod, Malcolm D
Our study explores inhibitory control across a range of widely recognised memory and behavioural tasks. Eighty-seven never-depressed participants completed a series of tasks designed to measure inhibitory control in memory and behaviour. Specifically, a variant of the selective retrieval-practice and the Think/No-Think tasks were employed as measures of memory inhibition. The Stroop-Colour Naming and the Go/No-Go tasks were used as measures of behavioural inhibition. Participants completed all 4 tasks. Task presentation order was counterbalanced across 3 separate testing sessions for each participant. Standard inhibitory forgetting effects emerged on both memory tasks but the extent of forgetting across these tasks was not correlated. Furthermore, there was no relationship between memory inhibition tasks and either of the main behavioural inhibition measures. At a time when cognitive inhibition continues to gain acceptance as an explanatory mechanism, our study raises fundamental questions about what we actually know about inhibition and how it is affected by the processing demands of particular inhibitory tasks.
Hamid, Aini Ismafairus Abd; Yusoff, Ahmad Nazlim; Mukari, Siti Zamratol-Mai Sarah; Mohamad, Mazlyfarina; Manan, Hanani Abdul; Hamid, Khairiah Abdul
Functional magnetic resonance imaging (fMRI) was used to investigate brain responses due to arithmetic working memory. Nine healthy young male subjects were given simple addition and subtraction instructions in noise and in quiet. The general linear model (GLM) and random field theory (RFT) were implemented in modelling the activation. The results showed that addition and subtraction evoked bilateral activation in Heschl's gyrus (HG), superior temporal gyrus (STG), inferior frontal gyrus (IFG), supramarginal gyrus (SG) and precentral gyrus (PCG). The HG, STG, SG and PCG activate higher number of voxels in noise as compared to in quiet for addition and subtraction except for IFG that showed otherwise. The percentage of signal change (PSC) in all areas is higher in quiet as compared to in noise. Surprisingly addition (not subtraction) exhibits stronger activation.
Schroeder, Paul J
BACKGROUND/STUDY CONTEXT: Declines in verbal working memory span task performance have been associated with deficits in the language processing abilities of healthy older adults, but it is unclear how storage and processing contribute to this relationship. Moreover, recent studies of the psychometric properties of span measures in the general cognitive literature highlight the need for a critical reassessment of age-related differences in working memory task performance. Forty-two young (Mage = 19.45 years) and 42 older participants (Mage = 73.00 years) completed a series of neuropsychological screening measures, four memory span tasks (one-syllable word span, three-syllable word span, reading span, and sentence span), and a measure of reading comprehension. Each span measure was completed under self-paced and timed encoding conditions. A 2 (age) × 2 (task type) × 2 (encoding conditions) mixed-model design was used. (1) Age effects were reliable for both simple and complex span task performance; (2) limiting the available encoding time yielded lower recall scores across tasks and exacerbated age differences in simple span performance; and (3) both encoding condition and age affected the relationship between each of the span measures and the relationship between span and reading comprehension. Declines in both storage and processing abilities contributed to age differences in span task performance and the relationship between span and reading comprehension. Although older people appear to benefit from task administration protocols that promote successful memory encoding, researchers should be aware of the potential risks to validity posed by such accommodations.
Zimmermann, Friederike G S; Eimer, Martin
The question whether the recognition of individual faces is mandatory or task-dependent is still controversial. We employed the N250r component of the event-related potential as a marker of the activation of representations of facial identity in visual memory, in order to find out whether identity-related information from faces is encoded and maintained even when facial identity is task-irrelevant. Pairs of faces appeared in rapid succession, and the N250r was measured in response to repetitions of the same individual face, as compared to presentations of two different faces. In Experiment 1, an N250r was present in an identity matching task where identity information was relevant, but not when participants had to detect infrequent targets (inverted faces), and facial identity was task-irrelevant. This was the case not only for unfamiliar faces, but also for famous faces, suggesting that even famous face recognition is not as automatic as is often assumed. In Experiment 2, an N250r was triggered by repetitions of non-famous faces in a task where participants had to match the view of each face pair, and facial identity had to be ignored. This shows that when facial features have to be maintained in visual memory for a subsequent comparison, identity-related information is retained as well, even when it is irrelevant. Our results suggest that individual face recognition is neither fully mandatory nor completely task-dependent. Facial identity is encoded and maintained in tasks that involve visual memory for individual faces, regardless of the to-be-remembered feature. In tasks without this memory component, irrelevant visual identity information can be completely ignored. Copyright © 2014 Elsevier Ltd. All rights reserved.
Excitotoxic median raphe lesions aggravate working memory storage performance deficits caused by scopolamine infusion into the dentate gyrus of the hippocampus in the inhibitory avoidance task in rats
Full Text Available The interactions between the median raphe nucleus (MRN serotonergic system and the septohippocampal muscarinic cholinergic system in the modulation of immediate working memory storage performance were investigated. Rats with sham or ibotenic acid lesions of the MRN were bilaterally implanted with cannulae in the dentate gyrus of the hippocampus and tested in a light/dark step-through inhibitory avoidance task in which response latency to enter the dark compartment immediately after the shock served as a measure of immediate working memory storage. MRN lesion per se did not alter response latency. Post-training intrahippocampal scopolamine infusion (2 and 4 µg/side produced a more marked reduction in response latencies in the lesioned animals compared to the sham-lesioned rats. Results suggest that the immediate working memory storage performance is modulated by synergistic interactions between serotonergic projections of the MRN and the muscarinic cholinergic system of the hippocampus.
Kvavilashvili, Lia; Kornbrot, Diana E; Mash, Veronica; Cockburn, Janet; Milne, Alan
Remembering to do something in the future (termed prospective memory) is distinguished from remembering information from the past (retrospective memory). Because prospective memory requires strong self-initiation, Craik (1986) predicted that age decrements should be larger in prospective than retrospective memory tasks. The aim of the present study was to assess Craik's prediction by examining the onset of age decline in two retrospective and three prospective memory tasks in the samples of young (18-30 years), young-old (61-70 years), and old-old (71-80 years) participants recruited from the local community. Results showed that although the magnitude of age effects varied across the laboratory prospective memory tasks, they were smaller than age effects in a simple three-item free recall task. Moreover, while reliable age decrements in both retrospective memory tasks of recognition and free recall were already present in the young-old group, in laboratory tasks of prospective memory they were mostly present in the old-old group only. In addition, older participants were more likely to report a retrospective than prospective memory failure as their most recent memory lapse, while the opposite pattern was present in young participants. Taken together, these findings highlight the theoretical importance of distinguishing effects of ageing on prospective and retrospective memory, and support and extend the results of a recent meta-analysis by Henry, MacLeod, Phillips, and Crawford (2004).
Morris, Ken A; Gold, Paul E
Epinephrine enhances memory in young adult rats, in part, by increasing blood glucose levels needed to modulate memory. In old rats, epinephrine is deficient at raising blood glucose levels and thus is only moderately effective at enhancing memory. In contrast, systemic glucose injections improve memory in old rats, with resulting memory performance equal to that of young rats. The diminished response of glucose to training in old rats may blunt downstream neurochemical and molecular mechanisms needed to upregulate memory processes. In the first experiment, young adult and old rats were trained on an inhibitory avoidance task with immediate post-training injections of aCSF or glucose into the dorsal hippocampus. Old rats had significant memory impairments compared to young rats 7 days after training. Intrahippocampal injections of glucose reversed age-related deficits, improving memory scores in old rats to values seen in young rats. A second experiment examined age-related changes in activation of the transcription factor CREB, which is widely implicated in memory formation and may act downstream of hormonal and metabolic signals. Activation was assessed in response to training with systemic injections of epinephrine and glucose at doses known to enhance memory. Young adult and old rats were trained on inhibitory avoidance with immediate post-training systemic injections of saline, epinephrine, or glucose. After training, old rats had significant impairments in CREB phosphorylation in area CA1 and the dentate gyrus region of the hippocampus, and in the basolateral and lateral amygdala. Epinephrine and glucose attenuated age-related deficits in CREB phosphorylation, but were more effective in the amygdala and hippocampus, respectively. Together, these results support the view that age-related changes in blood glucose responses to epinephrine contribute to memory impairments, which may be related to alterations in regional patterns of CREB phosphorylation. Copyright
Healey, M Karl; Miyake, Akira
We tested the hypothesis that retrieving target words in operation span (OSpan) involves attention-demanding processes. Participants completed the standard OSpan task and a modified version in which all equations preceded all target words. Recall took place under either full attention or easy versus hard divided-attention conditions. Recall suffered under divided attention with the recall decrement being greater for the hard secondary task. Moreover, secondary-task performance was disrupted more by the standard OSpan task than by the modified version with the hard secondary task showing the larger decrement. Finally, the time taken to start recalling the first word was considerably longer for the standard version than for the modified version. These results are consistent with the proposal that successful OSpan task performance in part involves the attention-demanding retrieval of targets from long-term memory.
Pardilla-Delgado, Enmanuelle; Payne, Jessica D
The Deese, Roediger and McDermott (DRM) task is a false memory paradigm in which subjects are presented with lists of semantically related words (e.g., nurse, hospital, etc.) at encoding. After a delay, subjects are asked to recall or recognize these words. In the recognition memory version of the task, subjects are asked whether they remember previously presented words, as well as related (but never presented) critical lure words ('doctor'). Typically, the critical word is recognized with high probability and confidence. This false memory effect has been robustly demonstrated across short (e.g., immediate, 20 min) and long (e.g., 1, 7, 60 d) delays between encoding and memory testing. A strength of using this task to study false memory is its simplicity and short duration. If encoding and retrieval components of the task occur in the same session, the entire task can take as little as 2 - 30 min. However, although the DRM task is widely considered a 'false memory' paradigm, some researchers consider DRM illusions to be based on the activation of semantic memory networks in the brain, and argue that such semantic gist-based false memory errors may actually be useful in some scenarios (e.g., remembering the forest for the trees; remembering that a word list was about "doctors", even though the actual word "doctor" was never presented for study). Remembering the gist of experience (instead of or along with individual details) is arguably an adaptive process and this task has provided a great deal of knowledge about the constructive, adaptive nature of memory. Therefore, researchers should use caution when discussing the overall reach and implications of their experiments when using this task to study 'false memory', as DRM memory errors may not adequately reflect false memories in the real world, such as false memory in eyewitness testimony, or false memories of sexual abuse.
Swan, Garrett; Wyble, Brad; Chen, Hui
It is well known that information can be held in memory while performing other tasks concurrently, such as remembering a color or number during a separate visual search task. However, it is not clear what happens to stored information in the face of unexpected tasks, such as the surprise questions that are often used in experiments related to inattentional and change blindness. Does the unpredicted shift in task context cause memory representations to be cleared in anticipation of new information? To answer this question, we ran two experiments where the task unexpectedly switched partway through the experiment with a surprise question. Half of the participants were asked to report the same attribute (Exp. 1 = Identity, Exp. 2 = Color) of a target stimulus in both presurprise and postsurprise trials, while for the other half, the reported attribute switched from identity to color (Exp. 1) or vice versa (Exp. 2). Importantly, all participants had to read an unexpected set of instructions and respond differently on the surprise trial. Accuracy on the surprise trial was higher for the same-attribute groups than the different-attribute groups. Furthermore, there was no difference in reaction time on the surprise trial between the two groups. These results suggest that information participants expected to report can survive an encounter with an unexpected task. The implication is that failures to report information on a surprise trial in many experiments reflect genuine differences in memory encoding, rather than forgetting or overwriting induced by the surprise question.
Qi, Xue-Lian; Meyer, Travis; Stanford, Terrence R; Constantinidis, Christos
The prefrontal cortex is considered essential for learning to perform cognitive tasks though little is known about how the representation of stimulus properties is altered by learning. To address this issue, we recorded neuronal activity in monkeys before and after training on a task that required visual working memory. After the subjects learned to perform the task, we observed activation of more prefrontal neurons and increased activity during working memory maintenance. The working memory-related increase in firing rate was due mostly to regular-spiking putative pyramidal neurons. Unexpectedly, the selectivity of neurons for stimulus properties and the ability of neurons to discriminate between stimuli decreased as the information about stimulus properties was apparently present in neural firing prior to training and neuronal selectivity degraded after training in the task. The effect was robust and could not be accounted for by differences in sampling sites, selection of neurons, level of performance, or merely the elapse of time. The results indicate that, in contrast to the effects of perceptual learning, mastery of a cognitive task degrades the apparent stimulus selectivity as neurons represent more abstract information related to the task. This effect is countered by the recruitment of more neurons after training.
Cutanda, Diana; Correa, Ángel; Sanabria, Daniel
The present study investigated whether participants can develop temporal preparation driven by auditory isochronous rhythms when concurrently performing an auditory working memory (WM) task. In Experiment 1, participants had to respond to an auditory target presented after a regular or an irregular sequence of auditory stimuli while concurrently performing a Sternberg-type WM task. Results showed that participants responded faster after regular compared with irregular rhythms and that this effect was not affected by WM load; however, the lack of a significant main effect of WM load made it difficult to draw any conclusion regarding the influence of the dual-task manipulation in Experiment 1. In order to enhance dual-task interference, Experiment 2 combined the auditory rhythm procedure with an auditory N-Back task, which required WM updating (monitoring and coding of the information) and was presumably more demanding than the mere rehearsal of the WM task used in Experiment 1. Results now clearly showed dual-task interference effects (slower reaction times [RTs] in the high- vs. the low-load condition). However, such interference did not affect temporal preparation induced by rhythms, with faster RTs after regular than after irregular sequences in the high-load and low-load conditions. These results revealed that secondary tasks demanding memory updating, relative to tasks just demanding rehearsal, produced larger interference effects on overall RTs in the auditory rhythm task. Nevertheless, rhythm regularity exerted a strong temporal preparation effect that survived the interference of the WM task even when both tasks competed for processing resources within the auditory modality. (c) 2015 APA, all rights reserved).
Chavez, Candice M.; McGaugh, James L.; Weinberger, Norman M.
Stress hormones released by an experience can modulate memory strength via the basolateral amygdala, which in turn acts on sites of memory storage such as the cerebral cortex [McGaugh, J. L. (2004). The amygdala modulates the consolidation of memories of emotionally arousing experiences. Annual Review of Neuroscience, 27, 1–28]. Stimuli that acquire behavioral importance gain increased representation in the cortex. For example, learning shifts the tuning of neurons in the primary auditory cor...
Lourenço, Joana S.; Hill, Johnathan H.; Maylor, Elizabeth A.
Previous research suggests that when intentions are encoded, participants establish an attention allocation policy based on their metacognitive beliefs about how demanding it will be to fulfill the prospective memory (PM) task. We investigated whether tacit PM demands can influence judgments about the cognitive effort required for success, and, as a result, affect ongoing task interference and PM performance. Participants performed a lexical decision task in which a PM task of responding to animal words was embedded. PM demands were tacitly manipulated by presenting participants with either typical or atypical animal exemplars at both instructions and practice (low vs. high tacit demands, respectively). Crucially, objective PM task demands were the same for all participants as PM targets were always atypical animals. Tacit demands affected participants’ attention allocation policies such that task interference was greater for the high than low demands condition. Also, PM performance was reduced in the low relative to the high demands condition. Participants in the low demands condition who succeeded to the first target showed a subsequent increase in task interference, suggesting adjustment to the higher than expected demands. This study demonstrates that tacit information regarding the PM task can affect ongoing task processing as well as harm PM performance when actual demands are higher than expected. Furthermore, in line with the proposal that attention allocation is a dynamic and flexible process, we found evidence that PM task experience can trigger changes in ongoing task interference. PMID:25983687
Valle, M T Costa; Couto-Pereira, N S; Lampert, C; Arcego, D M; Toniazzo, A P; Limberger, R P; Dallegrave, E; Dalmaz, C; Arbo, M D; Leal, M B
This study aimed to evaluate the effects of the subchronic consumption of energy drinks and their constituents (caffeine and taurine) in male Wistar rats using behavioural and oxidative measures. Energy drinks (ED 5, 7.5, and 10 mL/kg) or their constituents, caffeine (3.2 mg/kg) and taurine (40 mg/kg), either separately or in combination, were administered orally to animals for 28 days. Attention was measured though the ox-maze apparatus and the object recognition memory test. Following behavioural analyses, markers of oxidative stress, including SOD, CAT, GPx, thiol content, and free radicals, were measured in the prefrontal cortex, hippocampus, and striatum. The latency time to find the first reward was lower in animals that received caffeine, taurine, or a combination of both (P = 0.003; ANOVA/Bonferroni). In addition, these animals took less time to complete the ox-maze task (P = 0.0001; ANOVA/Bonferroni), and had better short-term memory (P energy drink. This might be related to other components contained in the energy drink, such as vitamins and minerals, which may have altered the ability of caffeine and taurine to modulate memory and attention.
Krueger, Lacy E.
Past studies have suggested that study time allocation partially mediates age relations on memory performance in a verbal task. To identify whether this applied to a different material modality, participants ages 20-87 completed a spatial task in addition to a traditional verbal task. In both the verbal and the spatial task, increased age was…
Nakao, Yoshiaki; Tamura, Toshiyo; Kodabashi, Atsushi; Fujimoto, Toshiro; Yarita, Masaru
In recent cognitive neuroscience, a lot of studies of the human working memory were examined, and electroencephalography (EEG) measurements during n-back task were often used. However, they were almost studied by event related potentials (ERP) analysis. In the ERP study, time-locked components can be elicited, but non time-locked components such as the modulated brain oscillatory activity might be lost by an averaging procedure. To elucidate the contribution of the modulations of the brain oscillatory activity to the human working memory, we examined event related desynchronization (ERD)/event related synchronization (ERS) analysis on the source waveforms during n-back task. Source waveforms were calculated from a source model which was constructed with the sources seeded from fMRI meta-analysis of n-back task and additional sources in the orbitofrontal cortex and the visual cortex estimated with P100 and P360 components in the n-back ERP. Our results suggested the network which included the prefrontal cortex and the parietal lobe had a contribution to human working memory process, and it was mediated by theta oscillatory activity. (author)
Dennett, Hugh W; McKone, Elinor; Tavashmi, Raka; Hall, Ashleigh; Pidcock, Madeleine; Edwards, Mark; Duchaine, Bradley
Many research questions require a within-class object recognition task matched for general cognitive requirements with a face recognition task. If the object task also has high internal reliability, it can improve accuracy and power in group analyses (e.g., mean inversion effects for faces vs. objects), individual-difference studies (e.g., correlations between certain perceptual abilities and face/object recognition), and case studies in neuropsychology (e.g., whether a prosopagnosic shows a face-specific or object-general deficit). Here, we present such a task. Our Cambridge Car Memory Test (CCMT) was matched in format to the established Cambridge Face Memory Test, requiring recognition of exemplars across view and lighting change. We tested 153 young adults (93 female). Results showed high reliability (Cronbach's alpha = .84) and a range of scores suitable both for normal-range individual-difference studies and, potentially, for diagnosis of impairment. The mean for males was much higher than the mean for females. We demonstrate independence between face memory and car memory (dissociation based on sex, plus a modest correlation between the two), including where participants have high relative expertise with cars. We also show that expertise with real car makes and models of the era used in the test significantly predicts CCMT performance. Surprisingly, however, regression analyses imply that there is an effect of sex per se on the CCMT that is not attributable to a stereotypical male advantage in car expertise.
Huang, Li-Yu; She, Hsiao-Ching; Chou, Wen-Chi; Chuang, Ming-Hua; Duann, Jeng-Ren; Jung, Tzyy-Ping
Many studies have reported that frontal theta and posterior alpha activities are associated with working memory tasks. However, fewer studies have focused on examining whether or not the frontal alpha or posterior theta can play a role in the working memory task. This study investigates electroencephalography (EEG) dynamics and connectivity among different brain regions' theta and alpha oscillations. The EEG was collected from undergraduate students (n = 64) while they were performing a Sternberg-like working memory task involving chemistry concepts. The results showed that the frontal midline cluster exhibited sustained theta augmentation across the periods of stimulus presentations, maintenance, and probe presentation, suggesting that the frontal midline theta might associate with facilitating the central execute function to maintain information in the working memory. Study of the central parietal and the occipital clusters revealed a sequence of theta augmentation followed by alpha suppression at constant intervals after the onset of stimulus and probe presentations, suggesting that the posterior theta might be associated with sensory processing, theta gating, or stimulus selection. It further suggests that the posterior alpha event-related de-synchronization (ERD) might be linked to direct information flow into and out of the long-term memory (LTM) and precede stimulus recognition. An alternating phasic alpha event-related synchronization (ERS) and ERD following the 1st stimulus and probe presentations were observed at the occipital cluster, in which alpha ERS might be linked to the inhibition of irrelevant information. © 2013.
Full Text Available Attention is a limited resource, and in order to improve processing of the attended information, competing processes must be suppressed. Although it is well established that an experimentally induced change in mood state comprises one type of competing process that can impair performance on a subsequent task, no study has investigated whether an emotionally valenced autobiographical memory (AM also can alter performance on a subsequent task. We therefore examined the effects of AM recall on cognitive performance. Healthy participants (n=20 per experiment recalled AMs in response to positive, negative, and neutral cue words. Following each AM participants completed a simple perceptual task (Experiment 1 or solved moderately difficult subtraction problems (Experiment 2. In Experiment 1 participants performed less accurately following exposure to positive or negative versus neutral cue words (ps<0.001, and also were less accurate following negative versus positive cue words (p<0.001. In Experiment 2, in contrast, no difference in accuracy or response times reached statistical significance. Performance accuracy even trended towards being higher following exposure to negative versus neutral cue words (p=0.08. The results of Experiment 1 suggested that recalling emotionally salient AMs reduces the attention directed toward a simple continuous performance task administered immediately following the AM task, conceivably due to persistent contemplation of the AM. The negative results of Experiment 2 suggested that the effect of AMs on attention was attenuated, however, by increasing the difficulty of the subsequent task. Our results have implications for patients with MDD, as performing cognitively demanding tasks may allow them to attenuate the impairing effects of negative rumination on cognition.
Schlickum, Marcus; Hedman, Leif; Enochsson, Lars; Henningsohn, Lars; Kjellin, Ann; Felländer-Tsai, Li
New strategies for selection and training of physicians are emerging. Previous studies have demonstrated a correlation between visual-spatial ability and visual working memory with surgical simulator performance. The aim of this study was to perform a detailed analysis on how these abilities are associated with metrics in simulator performance with different task content. The hypothesis is that the importance of visual-spatial ability and visual working memory varies with different task contents. Twenty-five medical students participated in the study that involved testing visual-spatial ability using the MRT-A test and visual working memory using the RoboMemo computer program. Subjects were also trained and tested for performance in three different surgical simulators. The scores from the psychometric tests and the performance metrics were then correlated using multivariate analysis. MRT-A score correlated significantly with the performance metrics Efficiency of screening (p = 0.006) and Total time (p = 0.01) in the GI Mentor II task and Total score (p = 0.02) in the MIST-VR simulator task. In the Uro Mentor task, both the MRT-A score and the visual working memory 3-D cube test score as presented in the RoboMemo program (p = 0.02) correlated with Total score (p = 0.004). In this study we have shown that some differences exist regarding the impact of visual abilities and task content on simulator performance. When designing future cognitive training programs and testing regimes, one might have to consider that the design must be adjusted in accordance with the specific surgical task to be trained in mind.
Shipstead, Zach; Engle, Randall W.
One approach to understanding working memory (WM) holds that individual differences in WM capacity arise from the amount of information a person can store in WM over short periods of time. This view is especially prevalent in WM research conducted with the visual arrays task. Within this tradition, many researchers have concluded that the average…
The present study sets out to explore the distinctive roles played by two working memory (WM) components in various aspects of L2 task-based speech planning and performance. A group of 40 post-intermediate proficiency level Chinese EFL learners took part in the empirical study. Following the tenets and basic principles of the…
Morey, Candice C.; Mall, Jonathan T.
Some evidence suggests that memory for serial order is domain-general. Evidence also points to asymmetries in interference between verbal and visual-spatial tasks. We confirm that concurrently remembering verbal and spatial serial lists provokes substantial interference compared with remembering a
Kane, Michael J.; Conway, Andrew R. A.; Miura, Timothy K.; Colflesh, Gregory J. H.
The n-back task requires participants to decide whether each stimulus in a sequence matches the one that appeared n items ago. Although n-back has become a standard "executive" working memory (WM) measure in cognitive neuroscience, it has been subjected to few behavioral tests of construct validity. A combined experimental-correlational study…
Roman, Adrienne S.; Pisoni, David B.; Kronenberger, William G.
The purpose of this study was to investigate the feasibility and validity of a modified version of Buschke's missing scan methodology, the Missing Scan Task (MST), to assess working memory capacity (WMC) and cognitive control processes in preschool children 3-6?years in age. Forty typically developing monolingual English-speaking children between…
Cevik, V.; Altun, A.
This study aims to investigate how working memory (WM) performances and instructional strategy choices affect learners' complex cognitive task performance in online environments. Three different e-learning environments were designed based on Merrill's (2006a) model of instructional strategies. The lack of experimental research on his framework is…
Mulligan, Neil W.; Dew, Ilana T. Z.
The generation manipulation has been critical in delineating differences between implicit and explicit memory. In contrast to past research, the present experiments indicate that generating from a rhyme cue produces as much perceptual priming as does reading. This is demonstrated for 3 visual priming tasks: perceptual identification, word-fragment…
Full Text Available Working memory (WM processes depend on our momentary mental state and therefore exhibit considerable fluctuations. Here, we investigate the interplay of task-preparatory and task-related brain activity as represented by pre-stimulus BOLD-fluctuations and spectral EEG from the retention periods of a visual WM task. Visual WM is used to maintain sensory information in the brain enabling the performance of cognitive operations and is associated with mental health.We tested 22 subjects simultaneously with EEG and fMRI while performing a visuo-verbal Sternberg task with two different loads, allowing for the temporal separation of preparation, encoding, retention and retrieval periods.Four temporally coherent networks - the default mode network (DMN, the dorsal attention, the right and the left WM network - were extracted from the continuous BOLD data by means of a group ICA. Subsequently, the modulatory effect of these networks’ pre-stimulus activation upon retention-related EEG activity in the theta, alpha and beta frequencies was analyzed. The obtained results are informative in the context of state-dependent information processing.We were able to replicate two well-known load-dependent effects: the frontal-midline theta increase during the task and the decrease of pre-stimulus DMN activity. As our main finding, these two measures seem to depend on each other as the significant negative correlations at frontal-midline channels suggested. Thus, suppressed pre-stimulus DMN levels facilitated later task related frontal midline theta increases. In general, based on previous findings that neuronal coupling in different frequency bands may underlie distinct functions in WM retention, our results suggest that processes reflected by spectral oscillations during retention seem not only to be online synchronized with activity in different attention-related networks but are also modulated by activity in these networks during preparation intervals.
Hampson, Robert E.; Song, Dong; Opris, Ioan; Santos, Lucas M.; Shin, Dae C.; Gerhardt, Greg A.; Marmarelis, Vasilis Z.; Berger, Theodore W.; Deadwyler, Sam A.
Objective Memory accuracy is a major problem in human disease and is the primary factor that defines Alzheimer’s’, aging and dementia resulting from impaired hippocampal function in medial temporal lobe. Development of a hippocampal memory neuroprosthesis that facilitates normal memory encoding in nonhuman primates (NHPs) could provide the basis for improving memory in human disease states. Approach NHPs trained to perform a short-term delayed match to sample (DMS) memory task were examined with multi-neuron recordings from synaptically connected hippocampal cell fields, CA1 and CA3. Recordings were analyzed utilizing a previously developed nonlinear multi-input multi-output (MIMO) neuroprosthetic model, capable of extracting CA3-to-CA1 spatiotemporal firing patterns during DMS performance. Main Results The MIMO model verified that specific CA3-to-CA1 firing patterns were critical for successful encoding of Sample phase information on more difficult DMS trials. This was validated by delivery of successful MIMO-derived encoding patterns via electrical stimulation to the same CA1 recording locations during the Sample phase which facilitated task performance in the subsequent delayed Match phase on difficult trials that required more precise encoding of Sample information. Significance These findings provide the first successful application of a neuroprosthesis designed to enhance and/or repair memory encoding in primate brain. PMID:24216292
Stuart, Matthias Bo; Sparsø, Jens
Task Graphs is a commonly used application model in research in computer-aided design tools for design space exploration of embedded systems, including system synthesis, scheduling and application mapping. These design tools need an estimate of the actual communication in the target system caused...... by the application modelled by the task graph. In this paper, we present a method for analytically deriving the worst-case traffic pattern when a task graph is mapped to a multiprocessor system-on-chip with a shared memory architecture. We describe the additionally needed information besides the dependencies...
Luksys, Gediminas; Ackermann, Sandra; Coynel, David; Fastenrath, Matthias; Gschwind, Leo; Heck, Angela; Rasch, Björn; Spalek, Klara; Vogler, Christian; Papassotiropoulos, Andreas; de Quervain, Dominique J-F
Memory performance is the result of many distinct mental processes, such as memory encoding, forgetting, and modulation of memory strength by emotional arousal. These processes, which are subserved by partly distinct molecular profiles, are not always amenable to direct observation. Therefore, computational models can be used to make inferences about specific mental processes and to study their genetic underpinnings. Here we combined a computational model-based analysis of memory-related proc...
Vu, Michael T; Du, Guizhi; Bayliss, Douglas A; Horner, Richard L
Basal forebrain cholinergic neurons are the main source of cortical acetylcholine, and their activation by histamine elicits cortical arousal. TWIK-like acid-sensitive K(+) (TASK) channels modulate neuronal excitability and are expressed on basal forebrain cholinergic neurons, but the role of TASK channels in the histamine-basal forebrain cholinergic arousal circuit is unknown. We first expressed TASK channel subunits and histamine Type 1 receptors in HEK cells. Application of histamine in vitro inhibited the acid-sensitive K(+) current, indicating a functionally coupled signaling mechanism. We then studied the role of TASK channels in modulating electrocortical activity in vivo using freely behaving wild-type (n = 12) and ChAT-Cre:TASK(f/f) mice (n = 12), the latter lacking TASK-1/3 channels on cholinergic neurons. TASK channel deletion on cholinergic neurons significantly altered endogenous electroencephalogram oscillations in multiple frequency bands. We then identified the effect of TASK channel deletion during microperfusion of histamine into the basal forebrain. In non-rapid eye movement sleep, TASK channel deletion on cholinergic neurons significantly attenuated the histamine-induced increase in 30-50 Hz activity, consistent with TASK channels contributing to histamine action on basal forebrain cholinergic neurons. In contrast, during active wakefulness, histamine significantly increased 30-50 Hz activity in ChAT-Cre:TASK(f/f) mice but not wild-type mice, showing that the histamine response depended upon the prevailing cortical arousal state. In summary, we identify TASK channel modulation in response to histamine receptor activation in vitro, as well as a role of TASK channels on cholinergic neurons in modulating endogenous oscillations in the electroencephalogram and the electrocortical response to histamine at the basal forebrain in vivo. Attentive states and cognitive function are associated with the generation of γ EEG activity. Basal forebrain
Rodríguez-Villagra, Odir Antonio; Göthe, Katrin; Oberauer, Klaus; Kliegl, Reinhold
We tested the limits of working-memory capacity (WMC) of young adults, old adults, and children with a memory-updating task. The task consisted of mentally shifting spatial positions within a grid according to arrows, their color signaling either only go (control) or go/no-go conditions. The interference model (IM) of Oberauer and Kliegl (2006)…
Johnson, Elizabeth L; Miller Singley, Alison T; Peckham, Andrew D; Johnson, Sheri L; Bunge, Silvia A
The capacity to keep multiple items in short-term memory (STM) improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.6 years) and adults (n = 54, mean age = 27.5 years) performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC) and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM overload task, after which the adults' pupils continued to dilate and the children's began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM.
Shin, Eunsam; Fabiani, Monica; Gratton, Gabriele
Studies using the lateralized readiness potential (LRP; an index of hand-specific motor preparation), suggest that the motor system can be activated on the basis of partial information, providing support for a parallel view of the human information processing system. However, data to the contrary have been obtained in memory-search paradigms, leading Heil et al. [Psychological Research 62 (1999) 289] to propose that hand-specific motor preparation cannot occur in parallel with memory scanning. To further investigate these findings we recorded the LRP in a fast-paced memory search task, in which the case of target letter and memory set size were manipulated and a choice-go/no-go procedure was used. The case of the test letter determined the response hand, whereas membership of the test stimulus in the memory set determined whether a response was required. We found different types of LRP effects as a function of time on task. Analyses based on the data from the first half of the experiment replicated those obtained by Heil et al. [Psychological Research 62 (1999) 289]. However, unlike Heil et al. [Psychological Research 62 (1999) 289], the second half of the data showed significant LRP activity on no-go trials and similar LRP onset latencies for go and no-go trials, as well as for different memory set size conditions in the stimulus-locked LRP waveforms. The response-related waveforms showed an earlier LRP onset in the set-size 4 than in the set-size 2 condition. These data suggest that motor preparation can occur simultaneously with memory search when participants are sufficiently practiced. Time-on-task and strategy differences between the two studies are discussed.
Herz, D. M.; Christensen, M. S.; Reck, C.
Neural oscillations in different frequency bands have been observed in a range of sensorimotor tasks and have been linked to coupling of spatially distinct neurons. The goal of this study was to detect a general motor network that is activated during phasic and tonic movements and to study the ta...
Geerligs, Linda; Saliasi, Emi; Renken, Remco J.; Maurits, Natasha M.; Lorist, Monicque M.
Recent studies have shown that aging has a large impact on connectivity within and between functional networks. An open question is whether elderly still have the flexibility to adapt functional network connectivity (FNC) to the demands of the task at hand. To study this, we collected fMRI data in
Gonthier, Corentin; Aubry, Alexandre; Bourdin, Béatrice
Working memory tasks designed for children usually present trials in order of ascending difficulty, with testing discontinued when the child fails a particular level. Unfortunately, this procedure comes with a number of issues, such as decreased engagement from high-ability children, vulnerability of the scores to temporary mind-wandering, and large between-subjects variations in number of trials, testing time, and proactive interference. To circumvent these problems, the goal of the present study was to demonstrate the feasibility of assessing working memory using an adaptive testing procedure. The principle of adaptive testing is to dynamically adjust the level of difficulty as the task progresses to match the participant's ability. We used this method to develop an adaptive complex span task (the ACCES) comprising verbal and visuo-spatial subtests. The task presents a fixed number of trials to all participants, allows for partial credit scoring, and can be used with children regardless of ability level. The ACCES demonstrated satisfying psychometric properties in a sample of 268 children aged 8-13 years, confirming the feasibility of using adaptive tasks to measure working memory capacity in children. A free-to-use implementation of the ACCES is provided.
Noreen, Saima; MacLeod, Malcolm D.
Using a novel autobiographical think/no-think procedure (ATNT; a modified version of the think/no-think task), 2 studies explored the extent to which we possess executive control over autobiographical memory. In Study 1, 30 never-depressed participants generated 12 positive and 12 negative autobiographical memories. Memories associated with…
Goonawardena, Anushka V.; Robinson, Lianne; Hampson, Robert E.; Riedel, Gernot
It is now well established that cannabinoid agonists such as [delta][superscript 9]-tetrahydrocannabinol (THC), anandamide, and WIN 55,212-2 (WIN-2) produce potent and specific deficits in working memory (WM)/short-term memory (STM) tasks in rodents. Although mediated through activation of CB1 receptors located in memory-related brain regions such…
Occhionero, Miranda; Cicogna, Piercarla; Esposito, Maria Jose
The aim of the present study was to deepen knowledge about the effect of a lowered vigilance state on time-based prospective memory (TBPM) performance. For this purpose 2 TBPM tasks (primary and interpolated), which shared a portion of the retention interval, and 3 reasoning tasks, as ongoing activities, were administered after total sleep deprivation and in a regular sleep condition. The results showed a detrimental effect of sleep deprivation on prospective memory performance and a partial dissociation between clock-checking behavior and time estimation for prospective compliance. This study clearly indicates that total sleep deprivation im- pairs the ability to complete multiple prospective task assignments in a timely fashion. Results are discussed suggesting the existence of different mechanisms involved in time monitoring and other cognitive functions underlying TBPM performance.
Peters, Benjamin; Bledowski, Christoph; Rieder, Maria; Kaiser, Jochen
Processing of auditory spatial and non-spatial information in working memory has been shown to rely on separate cortical systems. While previous studies have demonstrated differences in spatial versus non-spatial processing from the encoding of to-be-remembered stimuli onwards, here we investigated whether such differences would be detectable already prior to presentation of the sample stimulus. We analyzed broad-band magnetoencephalography data from 15 healthy adults during an auditory working memory paradigm starting with a visual cue indicating the task-relevant stimulus feature for a given trial (lateralization or pitch) and a subsequent 1.5-s pre-encoding phase. This was followed by a sample sound (0.2s), the delay phase (0.8s) and a test stimulus (0.2s) after which participants made a match/non-match decision. Linear discriminant functions were trained to decode task-specific signal patterns throughout the task, and temporal generalization was used to assess whether the neural codes discriminating between the tasks during the pre-encoding phase would recur during later task periods. The spatial versus non-spatial tasks could indeed be discriminated after the onset of the cue onwards, and decoders trained during the pre-encoding phase successfully discriminated the tasks during both sample stimulus encoding and during the delay phase. This demonstrates that task-specific neural codes are established already before the memorandum is presented and that the same patterns are reestablished during stimulus encoding and maintenance. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2015 Elsevier B.V. All rights reserved.
Jayaram, Vinay; Hohmann, Matthias; Just, Jennifer; Schölkopf, Bernhard; Grosse-Wentrup, Moritz
Task-induced amplitude modulation of neural oscillations is routinely used in brain-computer interfaces (BCIs) for decoding subjects' intents, and underlies some of the most robust and common methods in the field, such as common spatial patterns and Riemannian geometry. While there has been some interest in phase-related features for classification, both techniques usually presuppose that the frequencies of neural oscillations remain stable across various tasks. We investigate here whether features based on task-induced modulation of the frequency of neural oscillations enable decoding of subjects' intents with an accuracy comparable to task-induced amplitude modulation. We compare cross-validated classification accuracies using the amplitude and frequency modulated features, as well as a joint feature space, across subjects in various paradigms and pre-processing conditions. We show results with a motor imagery task, a cognitive task, and also preliminary results in patients with amyotrophic lateral sclerosis (ALS), as well as using common spatial patterns and Laplacian filtering. The frequency features alone do not significantly out-perform traditional amplitude modulation features, and in some cases perform significantly worse. However, across both tasks and pre-processing in healthy subjects the joint space significantly out-performs either the frequency or amplitude features alone. This result only does not hold for ALS patients, for whom the dataset is of insufficient size to draw any statistically significant conclusions. Task-induced frequency modulation is robust and straight forward to compute, and increases performance when added to standard amplitude modulation features across paradigms. This allows more information to be extracted from the EEG signal cheaply and can be used throughout the field of BCIs.
Tamara L. Powell
Full Text Available We investigated the mediating role of interference in developmental assessments of working memory (WM capacity across childhood, adolescence, and young adulthood. One hundred and forty-two participants completed two versions of visuospatial (colour matching task, CMT and verbal (letter matching task, LMT WM tasks, which systematically varied cognitive load in a high and low interference condition. Results showed similar developmental trajectories across high interference contexts (CMT- and LMT-Complex and divergent developmental growth patterns across low interference contexts (CMT- and LMT-Simple. Performance on tasks requiring greater cognitive control was in closer agreement with developmental predictions relative to simple recall guided tasks that rely solely on the storage components of WM. These findings suggest that developmental WM capacity, as measured by the CMT and LMT paradigms, can be better quantified using high interference contexts, in both content domains, and demonstrate steady increases in WM through to mid-adolescence.
1. Post-training administration of the opiate receptor antagonist naloxone facilitates the memory consolidation of a wide variety of tasks by rats. 2. Post-training administration of subanalgesic doses of beta-endorphin causes retrograde amnesia. This effect is shared by other opiates and opioids and is competitively antagonized by naloxone. These other opiates and opioids probably act by the release of endogenous beta-endorphin. 3. During various forms of aversive and non-aversive training beta-endorphin (but not Met-enkephalin) is released in the rat brain in amounts compatible with amnestic doses of this substance. 4. A number of treatments that cause naloxone-reversible retrograde amnesia, i.e. high doses of ACTH or adrenaline, low doses of morphine or of opioids, electroconvulsive shock, release massive amounts of beta-endorphin and Met-enkephalin in the rat brain. 5. These findings point to the existence of a physiological amnesic mechanism mediated by beta-endorphin, and perhaps other opioids as well, that normally prevents memory from being as good as it could be, and when operating at an exaggerated level may cause complete amnesia. 6. This mechanism interacts with other systems that influence memory consolidation (central dopaminergic and noradrenergic pathways, ACTH, peripheral adrenaline) and is a powerful modulator of their activity. 7. One possible role of the amnesic mechanism during training is to cause the rapid forgetting of adventitious learning that may interfere with acquisition of the main tasks for which animals are being trained. 8. Either through this action, or by some direct effect, beta-endorphin facilitates retrieval of a variety of behaviors in the rat when given before a test session.
Glou, Eric Le; Seugnet, Laurent; Shaw, Paul J.; Preat, Thomas; Goguel, Valérie
Objectives: Several lines of evidence indicate that sleep plays a critical role in learning and memory. The aim of this study was to evaluate anesthesia resistant memory following sleep deprivation in Drosophila. Design: Four to 16 h after aversive olfactory training, flies were sleep deprived for 4 h. Memory was assessed 24 h after training. Training, sleep deprivation, and memory tests were performed at different times during the day to evaluate the importance of the time of day for memory formation. The role of circadian rhythms was further evaluated using circadian clock mutants. Results Memory was disrupted when flies were exposed to 4 h of sleep deprivation during the consolidation phase. Interestingly, normal memory was observed following sleep deprivation when the memory test was performed during the 2 h preceding lights-off, a period characterized by maximum wake in flies. We also show that anesthesia resistant memory was less sensitive to sleep deprivation in flies with disrupted circadian rhythms. Conclusions Our results indicate that anesthesia resistant memory, a consolidated memory less costly than long-term memory, is sensitive to sleep deprivation. In addition, we provide evidence that circadian factors influence memory vulnerability to sleep deprivation and memory retrieval. Taken together, the data show that memories weakened by sleep deprivation can be retrieved if the animals are tested at the optimal circadian time. Citation: Le Glou E; Seugnet L; Shaw PJ; Preat T; Goguel V. Circadian modulation of consolidated memory retrieval following sleep deprivation in Drosophila. SLEEP 2012;35(10):1377-1384. PMID:23024436
Full Text Available Conflict monitoring is a process of stimulus evaluation and a pre-requisite for subsequent recruitment of cognitive control and behavioral adaptations. This study investigated how experimentally manipulated working-memory-related cognitive demand and aversive reinforcement modulate individual differences of conflict monitoring intensity and behavioral adjustments. Individual differences were assessed by means of an anxiety-related trait dimension (trait-BIS and by means of reasoning abilities–a core determinant of intelligence. Moreover, we investigated the special role of verbal reasoning ability and figural reasoning ability for the modulation of the conflict monitoring intensity. Ninety participants performed a go/nogo task with four conditions each comprising a combination of low vs. high working-memory-related cognitive demand and low vs. high aversive reinforcement. No effect of aversive reinforcement was observed for the N2 amplitude. The fronto-central nogo N2 amplitude was more pronounced for high demand vs. low demand suggesting that cognitive demand served as an aversive costly event. Higher total reasoning abilities were associated with more intense conflict monitoring and shorter response times with increasing aversive reinforcement (defined as verbal error-feedback vs. monetary loss. Individuals with higher trait-BIS scores demonstrated a more intense conflict monitoring even in conditions with low aversive reinforcement and also a more cautious responding (i.e., response times slowing with increasing aversive reinforcement indicating a focus on negative feedback prevention. The findings provide evidence for the conflict-monitoring theory and suggest that working-memory-related demand overrules the impact of aversive reinforcement on conflict monitoring intensity. Reasoning abilities and anxiety-related traits go along with an intensification of conflict monitoring but differences in the flexibility of behavioral adjustment.
Leue, Anja; Weber, Bernd; Beauducel, André
Conflict monitoring is a process of stimulus evaluation and a pre-requisite for subsequent recruitment of cognitive control and behavioral adaptations. This study investigated how experimentally manipulated working-memory-related cognitive demand and aversive reinforcement modulate individual differences of conflict monitoring intensity and behavioral adjustments. Individual differences were assessed by means of an anxiety-related trait dimension (trait-BIS) and by means of reasoning abilities-a core determinant of intelligence. Moreover, we investigated the special role of verbal reasoning ability and figural reasoning ability for the modulation of the conflict monitoring intensity. Ninety participants performed a go/nogo task with four conditions each comprising a combination of low vs. high working-memory-related cognitive demand and low vs. high aversive reinforcement. No effect of aversive reinforcement was observed for the N2 amplitude. The fronto-central nogo N2 amplitude was more pronounced for high demand vs. low demand suggesting that cognitive demand served as an aversive costly event. Higher total reasoning abilities were associated with more intense conflict monitoring and shorter response times with increasing aversive reinforcement (defined as verbal error-feedback vs. monetary loss). Individuals with higher trait-BIS scores demonstrated a more intense conflict monitoring even in conditions with low aversive reinforcement and also a more cautious responding (i.e., response times slowing) with increasing aversive reinforcement indicating a focus on negative feedback prevention. The findings provide evidence for the conflict monitoring theory and suggest that working-memory-related demand overrules the impact of aversive reinforcement on conflict monitoring intensity. Reasoning abilities and anxiety-related traits go along with an intensification of conflict monitoring but differences in the flexibility of behavioral adjustment.
Walsh, Stephanie J; Martin, Gerard M; Courage, Mary L
The development of prospective memory (PM) in 3-, 4-, and 5-year-old children (N=123) was assessed in two experiments using several naturalistic game-like tasks that varied in the explicitness of the cues for retrieval that they provided. The goals of the study were to evaluate age differences in PM (a) with the effects of retrospective memory (RM) factored out and (b) as a function of increasing retrieval cue specificity. Results from Experiment 1 showed that there were age differences in PM on a simulated Shopping Trip task that favored older children after age differences attributable to RM were identified in a hierarchical regression. PM and RM components followed the same developmental trajectory. Because the Shopping Trip task provided a visual cue for retrieval, a second naturalistic PM task that was incidental to the Shopping Trip task (i.e., to ask for stickers at the end of the shopping trip) was included but provided no explicit cue other than the end of Shopping Trip task itself. A binary logistic regression showed that age did not predict children who succeeded and those who did not succeed. Because the end of the Shopping Trip task might have cued PM, two new tasks without any explicit cues for retrieval were examined in Experiment 2. Logistic regressions revealed that age predicted PM success on both tasks. With additional cues following failure to retrieve the PM intention, nearly all children succeeded, but the number of cues needed increased with age. The joint and separate contributions of PM and RM to successful task performance are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.
Speer, Megan E.; Soldan, Anja
Although many epidemiological studies suggest the beneficial effects of higher cognitive reserve (CR) in reducing age-related cognitive decline and dementia risk, the neural basis of CR is poorly understood. To our knowledge, the current study represents the first electrophysiological investigation of the relationship between CR and neural reserve (i.e., neural efficiency and capacity). Specifically, we examined whether CR modulates event-related potentials (ERPs) associated with performance on a verbal recognition memory task with three set sizes (1, 4, or 7 letters) in healthy younger and older adults. Neural data showed that as task difficulty increased, the amplitude of the parietal P3b component during the probe phase decreased and its latency increased. Notably, the degree of these neural changes was negatively correlated with CR in both age groups, such that individuals with higher CR showed smaller changes in P3b amplitude and less slowing in P3b latency (i.e., smaller changes in the speed of neural processing) with increasing task difficulty, suggesting greater neural efficiency. These CR-related differences in neural efficiency may underlie reserve against neuropathology and age-related burden. PMID:25619663
Riby, Leigh M; McMurtrie, Hazel; Smallwood, Jonathan; Ballantyne, Carrie; Meikle, Andrew; Smith, Emily
The ingestion of a glucose-containing drink has been shown to improve cognitive performance, particularly memory functioning. However, it remains unclear as to the extent to which task domain and task difficulty moderate the glucose enhancement effect. The aim of this research was to determine whether boosts in performance are restricted to particular classes of memory (episodic v. semantic) or to tasks of considerable cognitive load. A repeated measures (25 g glucose v. saccharin), counterbalanced, double-blind design was used with younger and older adults. Participants performed a battery of episodic (e.g. paired associate learning) and semantic memory (e.g. category verification) tasks under low and high cognitive load. Electrophysiological measures (heart rate and galvanic skin response) of arousal and mental effort were also gathered. The results indicated that whilst glucose appeared to aid episodic remembering, cognitive load did not exaggerate the facilitative effect. For semantic memory, there was little evidence to suggest that glucose can boost semantic memory retrieval even when the load was manipulated. One exception was that glucose facilitated performance during the difficult category fluency task. Regardless, the present findings are consistent with the domain-specific account in which glucose acts primarily on the hippocampal region, which is known to support episodic memory. The possible contribution of the hippocampus in semantic memory processing is also discussed.
Walser, Moritz; Goschke, Thomas; Möschl, Marcus; Fischer, Rico
Recent prospective memory (PM) studies indicate that intentions are not always directly deactivated after completion, but that they entail aftereffects in terms of slower ongoing-task performance and/or commission errors on repeated (no-longer relevant) PM trials. In four experiments, we investigated whether aftereffects depend on the similarity between completed and currently performed PM-tasks. Aftereffects were reduced when PM-cues differed between the two PM-tasks (symbols vs. words) compared to when PM-cues belonged to the same category (symbols vs. symbols). This could be explained by the new dissimilar PM-task shifting spatial attention away from repeated PM-cues and, thus, attenuating processing of these cues. Moreover, a switch of the PM-response (to or within the manual modality) did not result in erroneous retrieval of the no-more-relevant PM-response (i.e., commission errors) but in erroneous retrieval of the currently relevant PM-response (i.e., false alarms). In addition, aftereffects vanished in conditions, in which participants did not perform a new PM-task. This finding indicates that forming a new PM-task set might be a prerequisite for aftereffects when the ongoing task changes between the two subsequent PM-tasks. Finally, we did not find evidence that forming a new, dissimilar PM-task representation led to overwriting of the completed intention representation, and thus to a change of the content or destabilization of its activation level.
Full Text Available Current perspectives on cognitive control acknowledge that individual differences in motivational dispositions may modulate cognitive processes in the absence of reward contingencies. This work aimed to study the relationship between individual differences in Behavioral Activation System (BAS sensitivity and the neural underpinnings involved in processing a switching cue in a task-switching paradigm. BAS sensitivity was hypothesized to modulate brain activity in frontal regions, ACC and the striatum. Twenty-eight healthy participants underwent fMRI while performing a switching task, which elicited activity in fronto-striatal regions during the processing of the switch cue. BAS sensitivity was negatively associated with activity in the lateral prefrontal cortex, anterior cingulate cortex and the ventral striatum. Combined with previous results, our data indicate that BAS sensitivity modulates the neurocognitive processes involved in task switching in a complex manner depending on task demands. Therefore, individual differences in motivational dispositions may influence cognitive processing in the absence of reward contingencies.
Smith, Carlyle; Smith, Danielle
The aim of Experiment 1 was to determine if moderate ethanol consumption at bedtime would result in memory loss for recently learned cognitive procedural and declarative tasks. The aim of Experiment 2 was to establish that the memory loss due to alcohol consumption at bedtime was due to the effect of alcohol on sleep states. In Experiment 1, participants were asked to learn a cognitive procedural task and a declarative task in the evening. Then, either the same evening or 2 nights later, they were asked to drink ethanol (0.7g/kg). Sleep was monitored for 3 days and re-testing of the tasks was done on the eighth day after training at the same time of day. In Experiment 2, subjects were asked to learn a cognitive procedural task (Tower of Hanoi) and a motor procedural task (Pursuit Rotor) in the late afternoon. Then one group was asked to drink ethanol (0.9 g/kg) right after task acquisition (5 hours before bed), while the other was asked to drink the same dose of ethanol just prior to bedtime. Re-testing was done 8 days later at the same time of day. Subjects in Experiment 1 were 15 college students between the ages of 19 and 24 that appeared to be in good health and were relatively naive in terms of drinking alcohol. Subjects in Experiment 2 were 13 college students in the same age range. These subjects were considered to be more experienced drinkers than subjects in Experiment 1 but were not judged to be heavy drinkers. In Experiment 1, the alcohol ingestion resulted in memory loss for the cognitive procedural task but not the declarative task. Further, the effect was seen when alcohol ingestion occurred the same day or 2 days after the end of acquisition. In Experiment 2, alcohol ingestion at bedtime impaired memory for the cognitive procedural and motor procedural tasks. By contrast, alcohol ingestion in the afternoon, immediately after the acquisition of these two tasks, did not impair memory. There were clear changes in the nature of rapid eye movement (REM
Vu, Michael T.; Du, Guizhi; Bayliss, Douglas A.
Basal forebrain cholinergic neurons are the main source of cortical acetylcholine, and their activation by histamine elicits cortical arousal. TWIK-like acid-sensitive K+ (TASK) channels modulate neuronal excitability and are expressed on basal forebrain cholinergic neurons, but the role of TASK channels in the histamine-basal forebrain cholinergic arousal circuit is unknown. We first expressed TASK channel subunits and histamine Type 1 receptors in HEK cells. Application of histamine in vitro inhibited the acid-sensitive K+ current, indicating a functionally coupled signaling mechanism. We then studied the role of TASK channels in modulating electrocortical activity in vivo using freely behaving wild-type (n = 12) and ChAT-Cre:TASKf/f mice (n = 12), the latter lacking TASK-1/3 channels on cholinergic neurons. TASK channel deletion on cholinergic neurons significantly altered endogenous electroencephalogram oscillations in multiple frequency bands. We then identified the effect of TASK channel deletion during microperfusion of histamine into the basal forebrain. In non-rapid eye movement sleep, TASK channel deletion on cholinergic neurons significantly attenuated the histamine-induced increase in 30–50 Hz activity, consistent with TASK channels contributing to histamine action on basal forebrain cholinergic neurons. In contrast, during active wakefulness, histamine significantly increased 30–50 Hz activity in ChAT-Cre:TASKf/f mice but not wild-type mice, showing that the histamine response depended upon the prevailing cortical arousal state. In summary, we identify TASK channel modulation in response to histamine receptor activation in vitro, as well as a role of TASK channels on cholinergic neurons in modulating endogenous oscillations in the electroencephalogram and the electrocortical response to histamine at the basal forebrain in vivo. SIGNIFICANCE STATEMENT Attentive states and cognitive function are associated with the generation of γ EEG activity
Yin, Jun; Zhou, Jifan; Xu, Haokui; Liang, Junying; Gao, Zaifeng; Shen, Mowei
The limited capacity of visual working memory (VWM) requires the existence of an efficient information selection mechanism. While it has been shown that under low VWM load, an irrelevant simple feature can be processed, its fate under high load (e.g., six objects) remains unclear. We explored this issue by probing the "irrelevant-change distracting effect," in which the change of a stored irrelevant feature affects performance. Simple colored shapes were used as stimuli, with color as the target. Using a whole-probe method (presenting six objects in both the memory and test arrays), in Experiment 1 we found that a change to one of the six shapes led to a significant distracting effect. Using a partial-probe method (presenting the probe either at the screen center or at a location selected from the memory array), in Experiment 2 we showed the distracting effect again. These results suggest that irrelevant simple features can be stored into VWM, regardless of memory load.
León, Irene; Tascón, Laura; Cimadevilla, José Manuel
Cognitive skills decline with age. Our ability to keep oriented in our surrounding environment was demonstrated to be influenced by factors like age and gender. Introduction of virtual reality based tasks improved assessment of spatial memory in humans. In this study, spatial orientation was assessed in a virtual memory task in order to determine the effect of aging and gender on navigational skills. Subjects from 45 to 74 years of age were organized in three groups (45-54, 55-64, 65-74 years old). Two levels of difficulty were considered. Results showed that males outperformed females in 65-74 years-old group. In addition to this, females showed a more noticeable poor performance in spatial memory than males, since memory differences appeared between all age groups. On the other hand, 65-74 year-old males showed an impaired performance in comparison with 45-54 year-old group. These results support that spatial memory becomes less accurate as we age and gender is an important factor influencing spatial orientation skills. Copyright © 2016 Elsevier B.V. All rights reserved.
Grimes, Kyrsten M; Zanjani, Anosha; Zakzanis, Konstantine K
Using meta-analytic methods, we sought to synthesize the research literature on memory impairment in schizophrenia. Additionally, we compared performances across memory measures to determine if task difficulty (e.g., effortful encoding and retrieval vs non-effortful encoding and retrieval) could account for variance across studies. Our primary measures of interest included the California Verbal Learning Test, Wechsler Memory Scale, Rey Auditory Verbal Learning Test, Hopkins Verbal Learning Test, Rey-Osterrieth Complex Figure Test, and the Benton Visual Retention Test. We searched for all studies that met inclusion criteria using PubMed, PsycINFO, Scholars Portal Search, and Google Scholar. Studies were included if: (i) they were published after 1980; (ii) healthy controls were compared to patients with schizophrenia; (iii) at least one of the noted measures of interest was employed in the primary study; and (iv) the primary study included data that could be transformed to point estimate effect sizes (i.e., Cohen's d). Cohen's d was calculated between patients and healthy controls, along with overall 95% confidence intervals. A two-tailed independent samples t-test was conducted to assess if performance differed on various paired subtests of the same domain. Large effect sizes were found for all memory tests. No significant differences were found between subtests. In conclusion, patients with schizophrenia experience significant verbal and visual memory impairments, which are not explained by task difficulty. Patients were unable to learn or retrieve more reliably despite repetition and cuing strategies, suggesting that memory impairment in the illness is not a function of task difficulty. © 2017 The Authors. Psychiatry and Clinical Neurosciences © 2017 Japanese Society of Psychiatry and Neurology.
Fraize, Nicolas; Carponcy, Julien; Joseph, Mickaël Antoine; Comte, Jean-Christophe; Luppi, Pierre-Hervé; Libourel, Paul-Antoine; Salin, Paul-Antoine; Malleret, Gaël; Parmentier, Régis
It is commonly accepted that sleep is beneficial to memory processes, but it is still unclear if this benefit originates from improved memory consolidation or enhanced information processing. It has thus been proposed that sleep may also promote forgetting of undesirable and non-essential memories, a process required for optimization of cognitive resources. We tested the hypothesis that non-rapid eye movement sleep (NREMS) promotes forgetting of irrelevant information, more specifically when processing information in working memory (WM), while REM sleep (REMS) facilitates the consolidation of important information. We recorded sleep patterns of rats trained in a radial maze in three different tasks engaging either the long-term or short-term storage of information, as well as a gradual level of interference. We observed a transient increase in REMS amount on the day the animal learned the rule of a long-term/reference memory task (RM), and, in contrast, a positive correlation between the performance of rats trained in a WM task involving an important processing of interference and the amount of NREMS or slow wave activity. Various oscillatory events were also differentially modulated by the type of training involved. Notably, NREMS spindles and REMS rapid theta increase with RM training, while sharp-wave ripples increase with all types of training. These results suggest that REMS, but also rapid oscillations occurring during NREMS would be specifically implicated in the long-term memory in RM, whereas NREMS and slow oscillations could be involved in the forgetting of irrelevant information required for WM. © 2016 Associated Professional Sleep Societies, LLC.
Full Text Available BACKGROUND: Sleep facilitates off-line consolidation of memories, as shown for learning of motor skills in the absence of concomitant distractors. We often perform complex tasks focusing our attention mostly on one single part of them. However, we are equally able to skillfully perform other concurrent tasks. One may even improve performance on disregarded parts of complex tasks, which were learned implicitly. In the present study we investigated the role of sleep in the off-line consolidation of procedural skills when attention is diverted from the procedural task because of interference from a concurrent task. METHODOLOGY/PRINCIPAL FINDINGS: We used a dual-task paradigm containing (i procedural serial reaction time task (SRTT, which was labeled as subordinate and unimportant and (ii declarative word-pair association task (WPAT, performed concomitantly. The WPAT served as a masked distractor to SRTT and was strongly reinforced by the instructions. One experimental and three control groups were tested. The experimental group was re-tested after two nights of sleep (sleep group, SG. The first control group had sleep deprivation on the first post-learning night (nighttime-awake group, NA, the second control group was tested in the morning and then re-tested after 12-hours (daytime-awake group, DA; the third one had the same assignments as DA but with a subsequent, instead of a concomitant, WPAT (daytime-awake-subsequent-WPAT group, DAs. We found SRTT performance gains in SG but not in NA and DA groups. Furthermore, SG reached similar learning gains in SRTT as the DAs group, which gained in SRTT performance because of post-training interference from the declarative task. CONCLUSIONS/SIGNIFICANCE: The results demonstrate that sleep allows off-line consolidation, which is resistant to deteriorating effects of a reinforced distractor on the implicit procedural learning and allowing for gains which are consistent with those produced when inhibited
Huang, Xianjun; Yang, Jin-Chen; Chang, Ruohan; Guo, Chunyan
Using unimodal auditory tasks of word-matching and meaning-matching, this study investigated how the phonological and semantic processes in Chinese disyllabic spoken word recognition are modulated by top-down mechanism induced by experimental tasks. Both semantic similarity and word-initial phonological similarity between the primes and targets were manipulated. Results showed that at early stage of recognition (~150-250 ms), an enhanced P2 was elicited by the word-initial phonological mismatch in both tasks. In ~300-500 ms, a fronto-central negative component was elicited by word-initial phonological similarities in the word-matching task, while a parietal negativity was elicited by semantically unrelated primes in the meaning-matching task, indicating that both the semantic and phonological processes can be involved in this time window, depending on the task requirements. In the late stage (~500-700 ms), a centro-parietal Late N400 was elicited in both tasks, but with a larger effect in the meaning-matching task than in the word-matching task. This finding suggests that the semantic representation of the spoken words can be activated automatically in the late stage of recognition, even when semantic processing is not required. However, the magnitude of the semantic activation is modulated by task requirements.
Jaldert O Rombouts
Full Text Available Intelligence is our ability to learn appropriate responses to new stimuli and situations. Neurons in association cortex are thought to be essential for this ability. During learning these neurons become tuned to relevant features and start to represent them with persistent activity during memory delays. This learning process is not well understood. Here we develop a biologically plausible learning scheme that explains how trial-and-error learning induces neuronal selectivity and working memory representations for task-relevant information. We propose that the response selection stage sends attentional feedback signals to earlier processing levels, forming synaptic tags at those connections responsible for the stimulus-response mapping. Globally released neuromodulators then interact with tagged synapses to determine their plasticity. The resulting learning rule endows neural networks with the capacity to create new working memory representations of task relevant information as persistent activity. It is remarkably generic: it explains how association neurons learn to store task-relevant information for linear as well as non-linear stimulus-response mappings, how they become tuned to category boundaries or analog variables, depending on the task demands, and how they learn to integrate probabilistic evidence for perceptual decisions.
Ivanova, M V; Dragoy, O V; Kuptsova, S V; Akinina Yu, S; Petrushevskii, A G; Fedina, O N; Turken, A; Shklovsky, V M; Dronkers, N F
Currently, a distributed bilateral network of frontal-parietal areas is regarded as the neural substrate of working memory (WM), with the verbal WM network being more left-lateralized. This conclusion is based primarily on functional magnetic resonance imaging (fMRI) data that provides correlational evidence for brain regions involved in a task. However, fMRI cannot differentiate the areas that are fundamentally required for performing a task. These data can only come from brain-injured individuals who fail the task after the loss of specific brain areas. In addition to the lack of complimentary data, is the issue of the variety in the WM tasks used to assess verbal WM. When different tasks are assumed to measure the same behavior, this may mask the contributions of different brain regions. Here, we investigated the neural substrate of WM by using voxel-based lesion symptom mapping (VLSM) in 49 individuals with stroke-induced left hemisphere brain injuries. These participants completed two different verbal WM tasks: complex listening span and a word 2-back task. Behavioral results indicated that the two tasks were only slightly related, while the VLSM analysis revealed different critical regions associated with each task. Specifically, significant detriments in performance on the complex span task were found with lesions in the inferior frontal gyrus, while for the 2-back task, significant deficits were seen after injury to the superior and middle temporal gyri. Thus, the two tasks depend on the structural integrity of different, non-overlapping frontal and temporal brain regions, suggesting distinct neural and cognitive mechanisms triggered by the two tasks: rehearsal and cue-dependent selection in the complex span task, versus updating/auditory recognition in the 2-back task. These findings call into question the common practice of using these two tasks interchangeably in verbal WM research and undermine the legitimacy of aggregating data from studies with
Meier, Beat; Zimmermann, Thomas D.
In prospective memory tasks different kinds of load can occur. Adding a prospective memory task can impose a load on ongoing task performance. Adding ongoing task load (OTL) can affect prospective memory performance. The existence of multiple target events increases prospective load (PL) and adding complexity to the to-be-remembered action increases retrospective load (RL). In two experiments, we systematically examined the effects of these different types of load on prospective memory performance. Results showed an effect of PL on costs in the ongoing task for categorical targets (Experiment 2), but not for specific targets (Experiment 1). RL and OTL both affected remembering the retrospective component of the prospective memory task. We suggest that PL can enhance costs in the ongoing task due to additional monitoring requirements. RL and OTL seem to impact the division of resources between the ongoing task and retrieval of the retrospective component, which may affect disengagement from the ongoing task. In general, the results demonstrate that the different types of load affect prospective memory differentially. PMID:26082709
Full Text Available The proinflammatory cytokine interleukin-1 (IL-1 is produced by many types of cells, including immune cells in the periphery and glia and neurons in the brain. The type I IL-1 receptor (IL-1r1 is primarily responsible for transmitting the inflammatory effects of IL-1 and mediates several biological functions by binding to either IL-1α or IL-1β. IL-1β activation is associated with hippocampus-dependent memory tasks. Although IL-1β impairs spatial memory under certain pathophysiological conditions, IL-1β may be required for the normal physiological regulation of hippocampal plasticity and memory. In addition, brain IL-1β levels are thought to change in the hippocampus in an age-dependent manner. These findings suggest that IL-1β may have a beneficial, temporary effect on learning and memory in young mice, but the matter remains unclear. Therefore, we hypothesized that hippocampal IL-1β has a beneficial effect on spatial learning and memory in young mice via IL-1r1, which is diminished in adults. We investigated the performance of young (3-month-old and adult (6-month-old wild-type mice, IL-1β knockout mice (IL-1βko and IL-1r1 knockout mice (IL-1r1ko in learning a spatial memory task with a fixed platform in a water maze (WM and measured the levels of IL-1β and IL-1α in the hippocampus and cortex of adult and young mice by using homogeneous time-resolved fluorescence (HTRF. Learning was significantly impaired in the training trials of the WM spatial memory task in young IL-1βko and IL-1r1ko mice but not in adult IL-1βko and IL-1r1ko mice. Moreover, young IL-1r1ko mice but not IL-1βko mice showed an impairment in long-term memory extinction, suggesting that IL-1α might facilitate memory extinction. In this study, the cytokine assay using HTRF did not indicate a higher expression of hippocampal IL-1 in young mice but cortical IL-1β and IL-1α were significantly increased in adult mice. We need to investigate the role of cortical IL-1
Rissman, Jesse; Gazzaley, Adam; D'Esposito, Mark
While a core function of the working memory (WM) system is the active maintenance of behaviorally relevant sensory representations, it is also critical that distracting stimuli are appropriately ignored. We used functional magnetic resonance imaging to examine the role of domain-general WM resources in the top-down attentional modulation of task-relevant and irrelevant visual representations. In our dual-task paradigm, each trial began with the auditory presentation of six random (high load) or sequentially ordered (low load) digits. Next, two relevant visual stimuli (e.g., faces), presented amongst two temporally interspersed visual distractors (e.g., scenes), were to be encoded and maintained across a 7-s delay interval, after which memory for the relevant images and digits was probed. When taxed by high load digit maintenance, participants exhibited impaired performance on the visual WM task and a selective failure to attenuate the neural processing of task-irrelevant scene stimuli. The over-processing of distractor scenes under high load was indexed by elevated encoding activity in a scene-selective region-of-interest relative to low load and passive viewing control conditions, as well as by improved long-term recognition memory for these items. In contrast, the load manipulation did not affect participants' ability to upregulate activity in this region when scenes were task-relevant. These results highlight the critical role of domain-general WM resources in the goal-directed regulation of distractor processing. Moreover, the consequences of increased WM load in young adults closely resemble the effects of cognitive aging on distractor filtering [Gazzaley, A., Cooney, J. W., Rissman, J., & D'Esposito, M. (2005). Top-down suppression deficit underlies working memory impairment in normal aging. Nature Neuroscience 8, 1298-1300], suggesting the possibility of a common underlying mechanism.
Ge, Ruiyang; Fu, Yan; Wang, DaHua; Yao, Li; Long, Zhiying
Autobiographical memory is the ability to recollect past events from one's own life. Both emotional tone and memory remoteness can influence autobiographical memory retrieval along the time axis of one's life. Although numerous studies have been performed to investigate brain regions involved in retrieving processes of autobiographical memory, the effect of emotional tone and memory age on autobiographical memory retrieval remains to be clarified. Moreover, whether the involvement of hippocampus in consolidation of autobiographical events is time dependent or independent has been controversial. In this study, we investigated the effect of memory remoteness (factor1: recent and remote) and emotional valence (factor2: positive and negative) on neural correlates underlying autobiographical memory by using functional magnetic resonance imaging (fMRI) technique. Although all four conditions activated some common regions known as "core" regions in autobiographical memory retrieval, there are some other regions showing significantly different activation for recent versus remote and positive versus negative memories. In particular, we found that bilateral hippocampal regions were activated in the four conditions regardless of memory remoteness and emotional valence. Thus, our study confirmed some findings of previous studies and provided further evidence to support the multi-trace theory which believes that the role of hippocampus involved in autobiographical memory retrieval is time-independent and permanent in memory consolidation.
Full Text Available Our ability to maintain small amounts of information in mind is critical for successful performance on a wide range of tasks. However, it remains unclear exactly how this maintenance is achieved. One possibility is that it is brought about using mechanisms that overlap with those used for attentional control. That is, the same mechanisms that we use to regulate and optimise our sensory processing may be recruited when we maintain information in visual short-term memory (VSTM. We aimed to test this hypothesis by exploring how distracter filtering is modified by concurrent VSTM load. We presented participants with sequences of target items, the order and location of which had to be maintained in VSTM. We also presented distracter items alongside the targets, and these distracters were graded such that they could be either very similar or dissimilar to the targets. We analysed scalp potentials using a novel multiple regression approach, which enabled us to explore the neural mechanisms by which the participants accommodated these variable distracters on a trial-to-trial basis. Critically, the effect of distracter filtering interacted with VSTM load; the same graded changes in perceptual similarity exerted effects of a different magnitude depending upon how many items participants were already maintaining in VSTM. These data provide compelling evidence that maintaining information in VSTM recruits an overlapping set of attentional control mechanisms that are otherwise used for distracter filtering.
Takács, Ádám; Kóbor, Andrea; Chezan, Júlia; Éltető, Noémi; Tárnok, Zsanett; Nemeth, Dezso; Ullman, Michael T; Janacsek, Karolina
Procedural memory, which is rooted in the basal ganglia, underlies the learning and processing of numerous automatized motor and cognitive skills, including in language. Not surprisingly, disorders with basal ganglia abnormalities have been found to show impairments of procedural memory. However, brain abnormalities could also lead to atypically enhanced function. Tourette syndrome (TS) is a candidate for enhanced procedural memory, given previous findings of enhanced TS processing of grammar, which likely depends on procedural memory. We comprehensively examined procedural learning, from memory formation to retention, in children with TS and typically developing (TD) children, who performed an implicit sequence learning task over two days. The children with TS showed sequence learning advantages on both days, despite a regression of sequence knowledge overnight to the level of the TD children. This is the first demonstration of procedural learning advantages in any disorder. The findings may further our understanding of procedural memory and its enhancement. The evidence presented here, together with previous findings suggesting enhanced grammar processing in TS, underscore the dependence of language on a system that also subserves visuomotor sequencing. Copyright © 2017 Elsevier Ltd. All rights reserved.
Kim, YouJin; Payant, Caroline; Pearson, Pamela
The extent to which individual differences in cognitive abilities affect the relationship among task complexity, attention to form, and second language development has been addressed only minimally in the cognition hypothesis literature. The present study explores how reasoning demands in tasks and working memory (WM) capacity predict learners'…
Zucco, Gesualdo M; Hummel, Thomas; Tomaiuolo, Francesco; Stevenson, Richard J
Amongst the techniques to assess olfactory functions, discrimination and cued identification are those most prone to the influence of odour short-term memory (STM). Discrimination task requires participants to detect the odd one out of three presented odourants. As re-smelling is not permitted, an un-intended STM load may generate, even though the task purports to assess discrimination ability. Analogously, cued identification task requires participants to smell an odour, and then select a label from three or four alternatives. As the interval between smelling and reading each label increases this too imposes a STM load, even though the task aims to measure identification ability. We tested whether modifying task design to reduce STM load improve performance on these tests. We examined five age-groups of participants (Adolescents, Young adults, Middle-aged, Elderly, very Elderly), some of whom should be more prone to the effects of STM load than others, on standard and modified tests of discrimination and identification. We found that using a technique to reduce STM load improved performance, especially for the very Elderly and Adolescent groups. Sources of error are now prevented. Findings indicate that STM load can adversely affect performance in groups vulnerable from memory impairment (i.e., very Elderly) and in those who may still be acquiring memory-based representations of familiar odours (i.e., Adolescents). It may be that adults in general would be even more sensitive to the effects of olfactory STM load reduction, if the odour-related task was more difficult. Copyright © 2013 Elsevier B.V. All rights reserved.
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.
Vuontela, Virve; Steenari, Maija-Riikka; Aronen, Eeva T.; Korvenoja, Antti; Aronen, Hannu J.; Carlson, Synnove
Using functional magnetic resonance imaging (fMRI) and n-back tasks we investigated whether, in 11-13-year-old children, spatial (location) and nonspatial (color) information is differentially processed during visual attention (0-back) and working memory (WM) (2-back) tasks and whether such cognitive task performance, compared to a resting state,…
Manousos A. Klados
Full Text Available There have been several attempts to account for the impact of Mathematical Anxiety (MA on brain activity with variable results. The present study examines the effects of MA on ERP amplitude during performance of simple arithmetic calculations and working memory tasks. Data were obtained from 32 university students as they solved four types of arithmetic problems (one- and two-digit addition and multiplication and a working memory task comprised of three levels of difficulty (1,2,and 3-back task. Compared to the Low-MA group, High-MA individuals demonstrated reduced ERP amplitude at frontocentral (between 180-320 ms and centroparietal locations (between 380-420 ms. These effects were independent of task difficulty/complexity, individual performance, and general state/trait anxiety levels. Results support the hypothesis that higher levels of self-reported MA are associated with lower cortical activation during the early stages of the processing of numeric stimuli in the context of cognitive tasks.
Lenneman, John K; Backs, Richard W
The objective of the study was to illustrate sensitivity and diagnosticity differences between cardiac measures and lane-keeping measures of driving performance. Previous research suggests that physiological measures can be sensitive to the effects of driving and side task performance and diagnostic of the source of the attentional demands. We hypothesized that increases in side task difficulty would elicit physiological change without reduction of driving task performance and that the side task demands would elicit patterns ofautonomic activity that map to specific attentional processing resources. Separately and concurrently, thirty-two participants performed a simulated driving task and verbal working memory task (with two levels of difficulty, 0 back and 3 back) separately and concurrently. Attentional demands were assessed through physiological and performance measures. Cardiac measures reflected changes in attentional demand from single- to dual-task driving with an n-back task, whereas lane-keeping measures did not. Furthermore, patterns of autonomic activity elicited by driving, n-back task, and dual-task driving with a 3-back task were consistent with our predictions about autonomic activity. Changes in cardiac measures without changes in lane-keeping measures provide evidence that cardiac measures can be sensitive to hidden costs in attention that do not manifest in coarse measures of driving performance. Furthermore, correct predictions regarding the patterns of autonomic activity elicited suggests that cardiac measures can serve as diagnostic tools for attention assessment. Because of the demonstrated differences in sensitivity and diagnosticity, researchers should consider the use of cardiac measures in addition to driving performance measures when studying attention in a driving simulator environment.
Nielsen, Malene Schjnning; Simonsen, Anja Hviid; Siersma, Volkert; Hasselbalch, Steen Gregers; Hoegh, Peter
Daily living requires the ability to perform dual-tasking. As cognitive skills decrease in dementia, performing a cognitive and motor task simultaneously become increasingly challenging and subtle gait abnormalities may even be present in pre-dementia stages. Therefore, a dual-tasking paradigm, such as the Timed Up and Go-Dual Task (TUG-DT), may be useful in the diagnostic assessment of mild cognitive impairment (MCI). To investigate the diagnostic and prognostic ability of a dual-tasking paradigm in patients with MCI or mild Alzheimer's disease (AD) and to evaluate the association between the dual-tasking paradigm and cerebrospinal fluid (CSF) AD biomarkers. The study is a prospective cohort study conducted in a clinical setting in two memory clinics. Eighty-six patients were included (28 MCI, 17 AD, 41 healthy controls (HC)). The ability to perform dual-tasking was evaluated by the TUG-DT. Patients underwent a standardized diagnostic assessment and were evaluated to determine progression yearly. ROC curve analysis illustrated a high discriminative ability of the dual-tasking paradigm in separating MCI patients from HC (AUC: 0.78, AUC: 0.82) and a moderate discriminative ability in separating MCI from AD (AUC: 0.73, AUC: 0.55). Performance discriminated clearly between all groups (p paradigm for progression and rate of cognitive decline. A moderately strong correlation between the dual-tasking paradigm and CSF AD biomarkers was observed. In our study, we found that patients with MCI and mild AD have increasing difficulties in dual-tasking compared to healthy elderly. Hence, the dual-tasking paradigm may be a potential complement in the diagnostic assessment in a typical clinical setting.
Pan, Yi; Hou, Xiu
Recent research has shown that the contents of working memory can alter our perceptual experiences of visual matching stimuli. However, it is possible that different kinds of working memory representations may distort visual perception in different ways. In the present study, we associated working memory representations with different attentional tags and then examined their effects on perceived duration. The results showed that working memory representations prolonged apparent duration when they were tagged as a target and shortened perceived duration when they were tagged as a distractor. This is the first demonstration that attentional tags can modulate working memory effects on perceptual experience. We conclude that the influences of working memory on visual perception are determined not only by what information to be held in memory, but also by how the information is represented in memory. Copyright © 2016 Elsevier B.V. All rights reserved.
Krasny-Pacini, Agata; Servant, Violette; Alzieu, Christine; Chevignard, Mathilde
Prospective memory (PM) has been shown to be impaired in children with acquired brain injuries (ABI) and is a major concern for parents. Few studies have addressed this issue and most used tasks that are not ecologically valid. The aims of this study were (1) to explore if children who have sustained an ABI suffer PM impairment, measured both by the Children's Cooking task (CCT) PM score and using the 2 PM subtests of the Rivermead Behavioral Memory Test (RBMT), and (2) to explore if the CCT PM score is sensitive to developmental changes in PM in typically developing children and in children with ABI. Fifty-four children with ABI and 33 typically developing controls participated in the study. Children with ABI had significantly lower PM scores and poorer performance in the CCT than their typically developing peers. PM scores increased significantly with age, indicating developmental progress of PM performance.
Lachman, Margie E.; Agrigoroaei, Stefan
Low perceived control is considered a risk factor for poor cognitive functioning, but the mechanisms are unclear. The goal of this study was to analyze anxiety and task interference as sequential mediators of the association between control beliefs and episodic memory. Cognitive-specific control beliefs were assessed prior to the lab session. State anxiety was assessed in the lab followed by a word list recall task. The frequency of intrusive thoughts during the memory task was reported by the participants as a measure of task interference after the completion of the cognitive testing. The results for 152 participants aged 22 to 84 years supported the predicted three-path mediation model. Lower levels of control beliefs were associated with higher state anxiety, which in turn affected episodic memory performance by increasing the likelihood of task interference, with age, sex, and verbal abilities as covariates. The implications of the results for developing interventions to improve memory performance are considered. PMID:21918911
Ortells, Juan J; Noguera, Carmen; Álvarez, Dolores; Carmona, Encarna; Houghton, George
The present study investigated whether semantic negative priming from single prime words depends on the availability of cognitive control resources. Participants with high vs. low working memory capacity (as assessed by their performance in complex span and attentional control tasks) were instructed to either attend to or ignore a briefly presented single prime word that was followed by either a semantically related or unrelated target word on which participants made a lexical decision. Individual differences in working memory capacity (WMC) mainly affected the processing of the ignored primes, but not the processing of the attended primes: While the latter produced reliable positive semantic priming for both high- and low-WMC participants, the former gave rise to reliable semantic negative priming only for high WMC participants, with low WMC participants showing the opposite positive priming effect. The present results extend previous findings in demonstrating that (a) single negative priming can reliably generalize to semantic associates of the prime words, and (b) a differential availability of cognitive control resources can reliably modulate the negative priming effect at a semantic level of representation.
Sripada, Rebecca K; Marx, Christine E; King, Anthony P; Rajaram, Nirmala; Garfinkel, Sarah N; Abelson, James L; Liberzon, Israel
Dehydroepiandrosterone (DHEA) is a neurosteroid with anxiolytic, antidepressant, and antiglucocorticoid properties. It is endogenously released in response to stress, and may reduce negative affect when administered exogenously. Although there have been multiple reports of DHEA's antidepressant and anxiolytic effects, no research to date has examined the neural pathways involved. In particular, brain imaging has not been used to link neurosteroid effects to emotion neurocircuitry. To investigate the brain basis of DHEA's impact on emotion modulation, patients were administered 400 mg of DHEA (N=14) or placebo (N=15) and underwent 3T fMRI while performing the shifted-attention emotion appraisal task (SEAT), a test of emotional processing and regulation. Compared with placebo, DHEA reduced activity in the amygdala and hippocampus, enhanced connectivity between the amygdala and hippocampus, and enhanced activity in the rACC. These activation changes were associated with reduced negative affect. DHEA reduced memory accuracy for emotional stimuli, and also reduced activity in regions associated with conjunctive memory encoding. These results demonstrate that DHEA reduces activity in regions associated with generation of negative emotion and enhances activity in regions linked to regulatory processes. Considering that activity in these regions is altered in mood and anxiety disorders, our results provide initial neuroimaging evidence that DHEA may be useful as a pharmacological intervention for these conditions and invite further investigation into the brain basis of neurosteroid emotion regulatory effects.
Full Text Available Extinction is not always permanent, as indicated by several types of recovery effects, such as the renewal effect, which may occur after a context change and points towards the importance of contextual cues. Strengthening the retrieval of extinction memory is a crucial aim of extinction-based psychotherapeutic treatments of anxiety disorders to prevent relapse. Stress is known to modulate learning and memory, with mostly enhancing effects on memory consolidation. However, whether such a consolidation-enhancing effect of acute stress can also be found for extinction memory has not yet been examined in humans. In this study, we investigated the effect of stress after extinction learning on the retrieval of extinction memory in a predictive learning renewal paradigm. Participants took the part of being the doctor of a fictitious patient and learned to predict whether certain food stimuli were associated with ‘stomach trouble’ in two different restaurants (contexts. On the first day, critical stimuli were associated with stomach trouble in context A (acquisition phase. On the second day, these associations were extinguished in context B. Directly after extinction, participants were either exposed to a stressor (socially evaluated cold pressor test; n = 22 or a control condition (n = 24. On the third day, we tested retrieval of critical associations in contexts A and B. Participants exposed to stress after extinction exhibited a reduced recovery of responding at test in context B, suggesting that stress may context-dependently enhance the consolidation of extinction memory. Furthermore, the increase in cortisol in response to the stressor was negatively correlated with the recovery of responding in context A. Our findings suggest that in parallel to the known effects of stress on the consolidation of episodic memory, stress also enhances the consolidation of extinction memory, which might be relevant for potential applications in extinction
Parker, Andrew; Dagnall, Neil
Two experiments investigated the effects of product-attribute associations on false consumer memory. In both experiments, subjects were presented with sets of related product attributes under incidental encoding conditions. Later, recognition memory was tested with studied attributes, non-studied but associated attributes (critical lures) and non-studied unrelated attributes. In Experiment 1, the effect of Need for Cognition (NFC) was assessed. It was found that individuals high in NFC recognised more presented attributes and falsely recognised more associative critical lures. The increase in both true and associative false memory was accompanied by a greater number of responses that index the retrieval of detailed episodic-like information. Experiment 2, replicated the main findings through an experimental manipulation of the encoding task that required subjects to consider purchase likelihood. Explanations for these findings are considered from the perspective of activation processes and knowledge structures in the form of gist-based representations.
Full Text Available By administering Simon, Simon switching, and operation-span working memory tasks to Cantonese-English bilingual children who varied in their first-language (L1, Cantonese and second-language (L2, English proficiencies, as quantified by standardized vocabulary test performance, the current study examined the effects of L1 and L2 proficiency on attentional control performance. Apart from mean performance, we conducted ex-Gaussian analyses to capture the modal and positive-tail components of participants’ reaction time distributions in the Simon task. Bilinguals’ L2 proficiency was associated with higher scores in the operation span task, and a shift of reaction time distributions in incongruent trials, relative to congruent trials (Simon effect in µ, and the tail size of reaction time distributions (τ regardless of trial types. Bilinguals’ L1 proficiency, which was strongly associated with participants’ age, showed similar results, except that it was not associated with the Simon effect in µ. In contrast, neither bilinguals’ L1 nor L2 proficiency modulated the global switch cost or local switch cost in the Simon switching task. After taking into account potential cognitive maturation by partialling out the participants’ age, only (a scores in the working memory task and (b RT in incongruent trials and (c Simon effect in µ in the Simon task could still be predicted by bilinguals’ L2 proficiency. Overall, the current findings suggest that bilingual children’s L2 proficiency was associated with their conflict resolution and working memory capacity, but not goal maintenance or task-set switching, when they performed the cognitive tasks that demanded attentional control. This was not entirely consistent with the findings of college-age bilinguals reported in previous studies.
Hakun, Jonathan G; Johnson, Nathan F
Older adults tend to over-activate regions throughout frontoparietal cortices and exhibit a reduced range of functional modulation during WM task performance compared to younger adults. While recent evidence suggests that reduced functional modulation is associated with poorer task performance, it remains unclear whether reduced range of modulation is indicative of general WM capacity-limitations. In the current study, we examined whether the range of functional modulation observed over multiple levels of WM task difficulty (N-Back) predicts in-scanner task performance and out-of-scanner psychometric estimates of WM capacity. Within our sample (60-77years of age), age was negatively associated with frontoparietal modulation range. Individuals with greater modulation range exhibited more accurate N-Back performance. In addition, despite a lack of significant relationships between N-Back and complex span task performance, range of frontoparietal modulation during the N-Back significantly predicted domain-general estimates of WM capacity. Consistent with previous cross-sectional findings, older individuals with less modulation range exhibited greater activation at the lowest level of task difficulty but less activation at the highest levels of task difficulty. Our results are largely consistent with existing theories of neurocognitive aging (e.g. CRUNCH) but focus attention on dynamic range of functional modulation asa novel marker of WM capacity-limitations in older adults. Copyright © 2017 Elsevier Inc. All rights reserved.
Kaushanskaya, Margarita; Gross, Megan; Buac, Milijana
We examined the effects of classroom bilingual experience in children on an array of cognitive skills. Monolingual English-speaking children were compared with children who spoke English as the native language and who had been exposed to Spanish in the context of dual-immersion schooling for an average of 2 years. The groups were compared on a measure of non-linguistic task-shifting; measures of verbal short-term and working memory; and measures of word learning. The two groups of children did not differ on measures of non-linguistic task-shifting and verbal short-term memory. However, the classroom-exposure bilingual group outperformed the monolingual group on the measure of verbal working memory and a measure of word learning. Together, these findings indicate that while exposure to a second language in a classroom setting may not be sufficient to engender changes in cognitive control, it can facilitate verbal memory and verbal learning. © 2014 John Wiley & Sons Ltd.
Zhou, Y D; Fuster, J M
Studies have shown that in the monkey's associative cerebral cortex, cells undergo sustained activation of discharge while the animal retains information for a subsequent action. Recent work has revealed the presence of such "memory cells" in the anterior parietal cortex (Brodmann's areas 3a, 3b, 1, and 2)--the early stage of the cortical somatosensory system. Here we inferred that, in a cross-modal visuo-haptic short-term memory task, somatosensory cells would react to visual stimuli associated with tactile features. Single-unit discharge was recorded from the anterior parietal cortex--including areas of hand representation--of monkeys performing a visuo-haptic delayed matching-to-sample task. Units changed firing frequency during the presentation of a visual cue that the animal had to remember for making a correct tactile choice between two objects at the end of a delay (retention period). Some units showed sustained activation during the delay. In some of them that activation differed depending on the cue. These findings suggest that units in somatosensory cortex react to visual stimuli behaviorally associated with tactile information. Further, the results suggest that some of these neurons are involved in short-term active memory and may, therefore, be part of cross-modal memory networks.
Kaushanskaya, Margarita; Gross, Megan; Buac, Milijana
We examined the effects of classroom bilingual experience in children on an array of cognitive skills. Monolingual English-speaking children were compared with children who spoke English as the native language and who had been exposed to Spanish in the context of dual-immersion schooling for an average of two years. The groups were compared on a measure of non-linguistic task-shifting; measures of verbal short-term and working memory; and measures of word-learning. The two groups of children did not differ on measures of non-linguistic task-shifting and verbal short-term memory. However, the classroom-exposure bilingual group outperformed the monolingual group on the measure of verbal working memory and a measure of word-learning. Together, these findings indicate that while exposure to a second language in a classroom setting may not be sufficient to engender changes in cognitive control, it can facilitate verbal memory and verbal learning. PMID:24576079
Vartanian, Oshin; Goel, Vinod
Lesion data suggest that right prefrontal cortex (PFC) plays a critical role in open-ended problem solving. To test this hypothesis, we scanned fifteen normal subjects with fMRI as they completed three types of anagram problems varying in the level of constraints placed on the search space. On unconstrained trials, they rearranged letters to generate solutions (e.g., Can you make a "Word with ZJAZ?"). On semantically constrained trials, they rearranged letters to generate solutions within particular semantic categories (e.g., Can you make a type of "Music with ZJAZ?"). On baseline trials, they rearranged letters to make specific words (e.g., Can you make the word "JAZZ with ZJAZ?"). As predicted, the critical comparison of unconstrained vs. semantically constrained trials revealed significant activation in right ventral lateral PFC, as well as left superior frontal gyrus, frontopolar cortex, right superior parietal lobe, right post central gyrus, and the occipital-parietal sulcus. Furthermore, activation in right ventral lateral PFC (BA 47) increased as the constraints placed on the anagram search space were reduced. We argue that the activation in right ventral lateral PFC is related to hypothesis generation in unconstrained settings, whereas activation in other structures is related to additional processes linked to anagram problems such as semantic retrieval, semantic categorization, and cognitive monitoring. These results extend the lesion data and imaging studies by demonstrating that a relative absence of constraints on the solution space is sufficient to engage right ventral lateral PFC in hypothesis generation tasks.
David W Smith
Full Text Available Recent studies lead to the conclusion that focused attention, through the activity of corticofugal and medial olivocochlear efferent pathways, modulates activity at the most peripheral aspects of the auditory system within the cochlea. In two experiments we investigated the effects of different intermodal attention manipulations on the response of outer hair cells (OHCs, and the control exerted by the medial olivocochlear (MOC efferent system. The effect of the MOCs on OHC activity was characterized by measuring the amplitude and rapid adaptation time course of distortion product otoacoustic emissions (DPOAEs. In the first, DPOAE recordings were compared while participants were reading a book and counting the occurrence of the letter a (auditory ignoring and while counting the either short- or long-duration eliciting tones (auditory attending. In the second, DPOAEs were recorded while subjects watched muted movies with subtitles (auditory ignoring/visual distraction and were compared with DPOAEs recorded while subjects counted the same tones (auditory attending as in experiment 1. In both experiments 1 and 2, the absolute level of the averaged DPOAEs recorded during the auditory-ignoring condition was statistically higher than that recorded in the auditory-attending condition. Efferent-induced rapid adaptation was evident in all DPOAE contours, under all attention conditions, suggesting that two medial efferent processes act independently to determine rapid adaptation, which is unaffected by attention, and the overall DPOAE level, which is significantly affected by changes in the focus of attention.
Groussard, M; Rauchs, G; Landeau, B; Viader, F; Desgranges, B; Eustache, F; Platel, H
Recognizing a musical excerpt without necessarily retrieving its title typically reflects the existence of a memory system dedicated to the retrieval of musical knowledge. The functional distinction between musical and verbal semantic memory has seldom been investigated. In this fMRI study, we directly compared the musical and verbal memory of 20 nonmusicians, using a congruence task involving automatic semantic retrieval and a familiarity task requiring more thorough semantic retrieval. In the former, participants had to access their semantic store to retrieve musical or verbal representations of melodies or expressions they heard, in order to decide whether these were then given the right ending or not. In the latter, they had to judge the level of familiarity of musical excerpts and expressions. Both tasks revealed activation of the left inferior frontal and posterior middle temporal cortices, suggesting that executive and selection processes are common to both verbal and musical retrievals. Distinct patterns of activation were observed within the left temporal cortex, with musical material mainly activating the superior temporal gyrus and verbal material the middle and inferior gyri. This cortical organization of musical and verbal semantic representations could explain clinical dissociations featuring selective disturbances for musical or verbal material. Copyright © 2010 Elsevier Inc. All rights reserved.
Han, Pi-Guo; Han, Lei; Bian, Yu-Long; Tian, Yu; Xu, Min-Xia; Gao, Feng-Qiang
Prospective memory (PM) is the process associated with the task of realizing delayed intentions in the future. Researchers distinguish two types of PM, namely time-based PM (tbPM) and event-based PM (ebPM). Experiment 1 investigated the developmental trajectory of 3- to 5-year-old preschool children's PM ability, and the occurrence of delayed retrieval (children execute the PM task in a larger window of opportunity) in both tbPM and ebPM tasks. Results revealed that the 5-year-old children outperformed the 3- and 4-year-old children in PM. Moreover, delayed retrieval was more likely to occur in tbPM task than in ebPM task. In Experiment 2, the influence of ongoing task (OT) difficulty on PM performance was investigated with a sample of 5-year-old children. Results revealed no significant effect of OT difficulty on PM performance. In Experiment 3, we improved children's motivation level to complete the OT, then explored the influence of OT difficulty on children's PM performance. Results revealed that the effect of OT difficulty on PM performance became significant after increasing the children's motivation to complete the OT. These results provide insights into the mechanism of attentional resource allocation in PM tasks and have crucial educational and social implications.
Full Text Available Finding neurobiological markers for neurodevelopmental disorders, such as attention deficit and hyperactivity disorder (ADHD, is a major objective of clinicians and neuroscientists. We examined if functional Magnetic Resonance Imaging (fMRI data from a few distinct visuospatial working memory (VSWM tasks enables accurately detecting cases with ADHD. We tested 20 boys with ADHD combined type and 20 typically developed (TD boys in four VSWM tasks that differed in feedback availability (feedback, no-feedback and reward size (large, small. We used a multimodal analysis based on brain activity in 16 regions of interest, significantly activated or deactivated in the four VSWM tasks (based on the entire participants' sample. Dimensionality of the data was reduced into 10 principal components that were used as the input variables to a logistic regression classifier. fMRI data from the four VSWM tasks enabled a classification accuracy of 92.5%, with high predicted ADHD probability values for most clinical cases, and low predicted ADHD probabilities for most TDs. This accuracy level was higher than those achieved by using the fMRI data of any single task, or the respective behavioral data. This indicates that task-based fMRI data acquired while participants perform a few distinct VSWM tasks enables improved detection of clinical cases.
Takeuchi, Hikaru; Taki, Yasuyuki; Hashizume, Hiroshi; Sassa, Yuko; Nagase, Tomomi; Nouchi, Rui; Kawashima, Ryuta
Working memory (WM) is an essential component for human higher order cognitive activities. Creativity has been essential to the development of human civilization. Previous studies from different fields have suggested creativity and capacity of WM have opposing characteristics possibly in terms of diffuse attention. However, despite a number of functional imaging studies on creativity, how creativity relates to brain activity during WM has never been investigated. In this functional magnetic resonance imaging (fMRI) study, we investigated this issue using an n-back WM paradigm and a psychometric measure of creativity (a divergent thinking test). A multiple regression analysis revealed that individual creativity was significantly and positively correlated with brain activity in the precuneus during the 2-back task (WM task), but not during the non-WM 0-back task. As the precuneus shows deactivation during cognitive tasks, our findings show that reduced task induced deactivation (TID) in the precuneus is associated with higher creativity measured by divergent thinking. The precuneus is included in the default mode network, which is deactivated during cognitive tasks. The magnitude of TID in the default mode network is considered to reflect the reallocation of cognitive resources from networks irrelevant to the performance of the task. Thus, our findings may indicate that individual creativity, as measured by the divergent thinking test, is related to the inefficient reallocation of attention, congruent with the idea that diffuse attention is associated with individual creativity. Copyright © 2010 Elsevier Inc. All rights reserved.
Barsegyan, Areg; McGaugh, James L.; Roozendaal, Benno
Noradrenergic activation of the basolateral complex of the amygdala (BLA) is well known to enhance the consolidation of long-term memory of highly emotionally arousing training experiences. The present study investigated whether such noradrenergic activation of the BLA also influences the consolidation of object-in-context recognition memory, a low-arousing training task assessing episodic-like memory. Male Sprague-Dawley rats were exposed to two identical objects in one context for either 3 ...
Strauss, Gregory P; Lee, Bern G; Waltz, James A; Robinson, Benjamin M; Brown, Jaime K; Gold, James M
Prior research provides evidence for aberrant cognition-emotion interactions in schizophrenia. In the current study, we aimed to extend these findings by administering the "distractor devaluation" task to 40 individuals with schizophrenia and 32 demographically matched healthy controls. The task consisted of a simple visual search task for neutral faces, followed by an evaluative response made for one of the search items (or a novel item) to determine whether prior attentional selection results in a devaluation of a previously unattended stimulus. We also manipulated working memory demands by preceding the search array with a memory array that required subjects to hold 0, 1, or 2 items in working memory while performing the search array and devaluation task, to determine whether the normative process by which attentional states influence evaluative response is limited by working memory capacity. Results indicated that individuals with schizophrenia demonstrated the typical distractor devaluation effect at working memory load 0, suggesting intact evaluative response. However, the devaluation effect was absent at working memory loads of 1 and 2, suggesting that normal evaluative responses can be abolished in people with schizophrenia when working memory capacity is exceeded. Thus, findings provide further evidence for normal evaluative response in schizophrenia, but clarify that these normal experiences may not hold when working memory demands are too high. Copyright © 2012 Elsevier B.V. All rights reserved.
Fura, David A.; Cohen, Gerald C.
This report describes interpreter composition techniques suitable for the formal specification and verification of a processor-memory module using the HOL theorem proving system. The processor-memory module is a multichip subsystem within a fault-tolerant embedded system under development within the Boeing Defense and Space Group. Modeling and verification methods were developed that permit provably secure composition at the transaction-level of specification, significantly reducing the complexity of the hierarchical verification of the system.
Gomarus, HK; Althaus, M; Wijers, AA; Minderaa, RB
Objective: Psychophysiological correlates of selective attention and working memory were investigated in a group of 18 healthy children using a visually presented selective mernory search task. Methods: Subjects had to memorize one (load 1) or 3 (load3) letters (memory set) and search for these
Müller-Oehring, Eva M.; Sullivan, Edith V.; Pfefferbaum, Adolf; Huang, Neng C.; Poston, Kathleen L.; Bronte-Stewart, Helen M.; Schulte, Tilman
Parkinson’s disease (PD) is associated with abnormal synchronization in basal ganglia-thalamo-cortical loops. We tested whether early PD patients without demonstrable cognitive impairment exhibit abnormal modulation of functional connectivity at rest, while engaged in a task, or both. PD and healthy controls underwent two functional MRI scans: a resting-state scan and a Stroop Match-to-Sample task scan. Rest-task modulation of basal ganglia (BG) connectivity was tested using seed-to-voxel connectivity analysis with task and rest time series as conditions. Despite substantial overlap of BG–cortical connectivity patterns in both groups, connectivity differences between groups had clinical and behavioral correlates. During rest, stronger putamen–medial parietal and pallidum–occipital connectivity in PD than controls was associated with worse task performance and more severe PD symptoms suggesting that abnormalities in resting-state connectivity denote neural network dedifferentiation. During the executive task, PD patients showed weaker BG-cortical connectivity than controls, i.e., between caudate–supramarginal gyrus and pallidum–inferior prefrontal regions, that was related to more severe PD symptoms and worse task performance. Yet, task processing also evoked stronger striatal–cortical connectivity, specifically between caudate–prefrontal, caudate–precuneus, and putamen–motor/premotor regions in PD relative to controls, which was related to less severe PD symptoms and better performance on the Stroop task. Thus, stronger task-evoked striatal connectivity in PD demonstrated compensatory neural network enhancement to meet task demands and improve performance levels. fMRI-based network analysis revealed that despite resting-state BG network compromise in PD, BG connectivity to prefrontal, premotor, and precuneus regions can be adequately invoked during executive control demands enabling near normal task performance. PMID:25280970
Müller-Oehring, Eva M; Sullivan, Edith V; Pfefferbaum, Adolf; Huang, Neng C; Poston, Kathleen L; Bronte-Stewart, Helen M; Schulte, Tilman
Parkinson's disease (PD) is associated with abnormal synchronization in basal ganglia-thalamo-cortical loops. We tested whether early PD patients without demonstrable cognitive impairment exhibit abnormal modulation of functional connectivity at rest, while engaged in a task, or both. PD and healthy controls underwent two functional MRI scans: a resting-state scan and a Stroop Match-to-Sample task scan. Rest-task modulation of basal ganglia (BG) connectivity was tested using seed-to-voxel connectivity analysis with task and rest time series as conditions. Despite substantial overlap of BG-cortical connectivity patterns in both groups, connectivity differences between groups had clinical and behavioral correlates. During rest, stronger putamen-medial parietal and pallidum-occipital connectivity in PD than controls was associated with worse task performance and more severe PD symptoms suggesting that abnormalities in resting-state connectivity denote neural network dedifferentiation. During the executive task, PD patients showed weaker BG-cortical connectivity than controls, i.e., between caudate-supramarginal gyrus and pallidum-inferior prefrontal regions, that was related to more severe PD symptoms and worse task performance. Yet, task processing also evoked stronger striatal-cortical connectivity, specifically between caudate-prefrontal, caudate-precuneus, and putamen-motor/premotor regions in PD relative to controls, which was related to less severe PD symptoms and better performance on the Stroop task. Thus, stronger task-evoked striatal connectivity in PD demonstrated compensatory neural network enhancement to meet task demands and improve performance levels. fMRI-based network analysis revealed that despite resting-state BG network compromise in PD, BG connectivity to prefrontal, premotor, and precuneus regions can be adequately invoked during executive control demands enabling near normal task performance.
Elizabeth L. Johnson
Full Text Available The capacity to keep multiple items in short-term memory (STM improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.5 years and adults (n = 54, mean age = 27.5 years performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM Overload task, after which the adults’ pupils continued to dilate and the children’s began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage attention from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM Overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM.
Kalpouzos, Gr?goria; Eriksson, Johan
Background: While the use of different cognitive strategies when encoding episodic memory information has been extensively investigated, modulation of brain activity by memory self-efficacy beliefs has not been studied yet. Methodology/Principal Findings: Sixteen young adults completed the prospective and retrospective metamemory questionnaire, providing individual subjective judgments of everyday memory function. The day after, using functional magnetic resonance imaging, the participants ha...
Steinmetz, Adam B.; Ng, Ka H.; Freeman, John H.
Amygdala lesions impair, but do not prevent, acquisition of cerebellum-dependent eyeblink conditioning suggesting that the amygdala modulates cerebellar learning. Two-factor theories of eyeblink conditioning posit that a fast-developing memory within the amygdala facilitates slower-developing memory within the cerebellum. The current study tested…
This is a memorial volume dedicated to A. L. S. Corner, previously Professor in Oxford, who published important results on algebra, especially on the connections of modules with endomorphism algebras. The volume contains refereed contributions which are related to the work of Corner.It contains also an unpublished extended paper of Corner himself. A memorial volume with important contributions related to algebra.
Alvares, Lucas de Oliveira; Engelke, Douglas Senna; Diehl, Felipe; Scheffer-Teixeira, Robson; Haubrich, Josue; Cassini, Lindsey de Freitas; Molina, Victor Alejandro; Quillfeldt, Jorge Alberto
The modulation of memory processes is one of the several functions of the endocannabinoid system (ECS) in the brain, with CB1 receptors highly expressed in areas such as the dorsal hippocampus. Experimental evidence suggested an important role of the ECS in aversively motivated memories. Similarly, glucocorticoids released in response to stress…
Avancini, Chiara; Galfano, Giovanni; Szűcs, Dénes
Event-related potential (ERP) studies have detected several characteristic consecutive amplitude modulations in both implicit and explicit mental arithmetic tasks. Implicit tasks typically focused on the arithmetic relatedness effect (in which performance is affected by semantic associations between numbers) while explicit tasks focused on the distance effect (in which performance is affected by the numerical difference of to-be-compared numbers). Both task types elicit morphologically similar ERP waves which were explained in functionally similar terms. However, to date, the relationship between these tasks has not been investigated explicitly and systematically. In order to fill this gap, here we examined whether ERP effects and their underlying cognitive processes in implicit and explicit mental arithmetic tasks differ from each other. The same group of participants performed both an implicit number-matching task (in which arithmetic knowledge is task-irrelevant) and an explicit arithmetic-verification task (in which arithmetic knowledge is task-relevant). 129-channel ERP data differed substantially between tasks. In the number-matching task, the arithmetic relatedness effect appeared as a negativity over left-frontal electrodes whereas the distance effect was more prominent over right centro-parietal electrodes. In the verification task, all probe types elicited similar N2b waves over right fronto-central electrodes and typical centro-parietal N400 effects over central electrodes. The distance effect appeared as an early-rising, long-lasting left parietal negativity. We suggest that ERP effects in the implicit task reflect access to semantic memory networks and to magnitude discrimination, respectively. In contrast, effects of expectation violation are more prominent in explicit tasks and may mask more delicate cognitive processes. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.
Boraxbekk, Carl-Johan; Stomby, Andreas; Ryberg, Mats; Lindahl, Bernt; Larsson, Christel; Nyberg, Lars; Olsson, Tommy
It has been suggested that overweight is negatively associated with cognitive functions. The aim of this study was to investigate whether a reduction in body weight by dietary interventions could improve episodic memory performance and alter associated functional brain responses in overweight and obese women. 20 overweight postmenopausal women were randomized to either a modified paleolithic diet or a standard diet adhering to the Nordic Nutrition Recommendations for 6 months. We used functional magnetic resonance imaging to examine brain function during an episodic memory task as well as anthropometric and biochemical data before and after the interventions. Episodic memory performance improved significantly (p = 0.010) after the dietary interventions. Concomitantly, brain activity increased in the anterior part of the right hippocampus during memory encoding, without differences between diets. This was associated with decreased levels of plasma free fatty acids (FFA). Brain activity increased in pre-frontal cortex and superior/middle temporal gyri. The magnitude of increase correlated with waist circumference reduction. During episodic retrieval, brain activity decreased in inferior and middle frontal gyri, and increased in middle/superior temporal gyri. Diet-induced weight loss, associated with decreased levels of plasma FFA, improves episodic memory linked to increased hippocampal activity. © 2015 S. Karger GmbH, Freiburg.
Full Text Available Objective: It has been suggested that overweight is negatively associated with cognitive functions. The aim of this study was to investigate whether a reduction in body weight by dietary interventions could improve episodic memory performance and alter associated functional brain responses in overweight and obese women. Methods: 20 overweight postmenopausal women were randomized to either a modified paleolithic diet or a standard diet adhering to the Nordic Nutrition Recommendations for 6 months. We used functional magnetic resonance imaging to examine brain function during an episodic memory task as well as anthropometric and biochemical data before and after the interventions. Results: Episodic memory performance improved significantly (p = 0.010 after the dietary interventions. Concomitantly, brain activity increased in the anterior part of the right hippocampus during memory encoding, without differences between diets. This was associated with decreased levels of plasma free fatty acids (FFA. Brain activity increased in pre-frontal cortex and superior/middle temporal gyri. The magnitude of increase correlated with waist circumference reduction. During episodic retrieval, brain activity decreased in inferior and middle frontal gyri, and increased in middle/superior temporal gyri. Conclusions: Diet-induced weight loss, associated with decreased levels of plasma FFA, improves episodic memory linked to increased hippocampal activity.
Pezze, Marie A; Marshall, Hayley J; Fone, Kevin C F; Cassaday, Helen J
Previous studies have shown that dopamine D1 receptor antagonists impair novel object recognition memory but the effects of dopamine D1 receptor stimulation remain to be determined. This study investigated the effects of the selective dopamine D1 receptor agonist SKF81297 on acquisition and retrieval in the novel object recognition task in male Wistar rats. SKF81297 (0.4 and 0.8 mg/kg s.c.) given 15 min before the sampling phase impaired novel object recognition evaluated 10 min or 24 h later. The same treatments also reduced novel object recognition memory tested 24 h after the sampling phase and when given 15 min before the choice session. These data indicate that D1 receptor stimulation modulates both the encoding and retrieval of object recognition memory. Microinfusion of SKF81297 (0.025 or 0.05 μg/side) into the prelimbic sub-region of the medial prefrontal cortex (mPFC) in this case 10 min before the sampling phase also impaired novel object recognition memory, suggesting that the mPFC is one important site mediating the effects of D1 receptor stimulation on visual recognition memory. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.
Meyer, Travis; Qi, Xue-Lian; Stanford, Terrence R.; Constantinidis, Christos
The prefrontal cortex is known to represent different types of information in working memory. Contrasting theories propose that the dorsal and ventral regions of the lateral prefrontal cortex are innately specialized for the representation of spatial and non-spatial information respectively (Goldman-Rakic, 1996), or that the two regions are shaped by the demands of cognitive tasks imposed on them (Miller, 2000). To resolve this issue, we recorded from neurons in the two regions, prior to and at multiple stages of training monkeys on visual working memory tasks. Prior to training, substantial functional differences were present between the two regions. Dorsal prefrontal cortex exhibited higher overall responsiveness to visual stimuli and higher selectivity for spatial information. After training, stimulus selectivity generally decreased, though dorsal prefrontal cortex retained higher spatial selectivity regardless of task performed. Ventral prefrontal cortex appeared to be affected to a greater extent by the nature of task performed. Our results indicate that regional specialization for stimulus selectivity is present in the primate prefrontal cortex regardless of training. Dorsal areas of the prefrontal cortex are inherently organized to represent spatial information and training has little influence on this spatial bias. Ventral areas are biased toward non-spatial information although they are more influenced by training both in terms of activation and changes in stimulus selectivity. PMID:21525266
Sideman, Noah; Chaitanya, Ganne; He, Xiaosong; Doucet, Gaelle; Kim, Na Young; Sperling, Michael R; Sharan, Ashwini D; Tracy, Joseph I
In epilepsy, asymmetries in the organization of mesial temporal lobe (MTL) functions help determine the cognitive risk associated with procedures such as anterior temporal lobectomy. Past studies have investigated the change/shift in a visual episodic memory laterality index (LI) in mesial temporal lobe structures through functional magnetic resonance imaging (fMRI) task activations. Here, we examine whether underlying task-related functional connectivity (FC) is concordant with such standard fMRI laterality measures. A total of 56 patients with temporal lobe epilepsy (TLE) (Left TLE [LTLE]: 31; Right TLE [RTLE]: 25) and 34 matched healthy controls (HC) underwent fMRI scanning during performance of a scene encoding task (SET). We assessed an activation-based LI of the hippocampal gyrus (HG) and parahippocampal gyrus (PHG) during the SET and its correspondence with task-related FC measures. Analyses involving the HG and PHG showed that the patients with LTLE had a consistently higher LI (right-lateralized) than that of the HC and group with RTLE, indicating functional reorganization. The patients with RTLE did not display a reliable contralateral shift away from the pathology, with the mesial structures showing quite distinct laterality patterns (HG, no laterality bias; PHG, no evidence of LI shift). The FC data for the group with LTLE provided confirmation of reorganization effects, revealing that a rightward task LI may be based on underlying connections between several left-sided regions (middle/superior occipital and left medial frontal gyri) and the right PHG. The FCs between the right HG and left anterior cingulate/medial frontal gyri were also observed in LTLE. Importantly, the data demonstrate that the areas involved in the LTLE task activation shift to the right hemisphere showed a corresponding increase in task-related FCs between the hemispheres. Altered laterality patterns based on mesial temporal lobe epilepsy (MTLE) pathology manifest as several
De Dreu, Carsten K W; Nijstad, Bernard A; Baas, Matthijs; Wolsink, Inge; Roskes, Marieke
Anecdotes from creative eminences suggest that executive control plays an important role in creativity, but scientific evidence is sparse. Invoking the Dual Pathway to Creativity Model, the authors hypothesize that working memory capacity (WMC) relates to creative performance because it enables persistent, focused, and systematic combining of elements and possibilities (persistence). Study 1 indeed showed that under cognitive load, participants performed worse on a creative insight task. Study 2 revealed positive associations between time-on-task and creativity among individuals high but not low in WMC, even after controlling for general intelligence. Study 3 revealed that across trials, semiprofessional cellists performed increasingly more creative improvisations when they had high rather than low WMC. Study 4 showed that WMC predicts original ideation because it allows persistent (rather than flexible) processing. The authors conclude that WMC benefits creativity because it enables the individual to maintain attention focused on the task and prevents undesirable mind wandering.
memory through influences invol- ving noradrenergic receptors in the amygdala. , .. . .... C-Qc- u , Y\\ o C r z A-, - r V r a ,, ~ Epinephrine Effects...epinephrine affects memory through influences involving the amygdala is supported by the finding that lesions of the stria terminalis (ST), a major...interpreted these findings as indicating that peripherally- administered naloxone influences memory by blocking opioid peptide recep- tors located within
Pauline L Baniqued
Full Text Available Although some studies have shown that cognitive training can produce improvements to untrained cognitive domains (far transfer, many others fail to show these effects, especially when it comes to improving fluid intelligence. The current study was designed to overcome several limitations of previous training studies by incorporating training expectancy assessments, an active control group, and "Mind Frontiers," a video game-based mobile program comprised of six adaptive, cognitively demanding training tasks that have been found to lead to increased scores in fluid intelligence (Gf tests. We hypothesize that such integrated training may lead to broad improvements in cognitive abilities by targeting aspects of working memory, executive function, reasoning, and problem solving. Ninety participants completed 20 hour-and-a-half long training sessions over four to five weeks, 45 of whom played Mind Frontiers and 45 of whom completed visual search and change detection tasks (active control. After training, the Mind Frontiers group improved in working memory n-back tests, a composite measure of perceptual speed, and a composite measure of reaction time in reasoning tests. No training-related improvements were found in reasoning accuracy or other working memory tests, nor in composite measures of episodic memory, selective attention, divided attention, and multi-tasking. Perceived self-improvement in the tested abilities did not differ between groups. A general expectancy difference in problem-solving was observed between groups, but this perceived benefit did not correlate with training-related improvement. In summary, although these findings provide modest evidence regarding the efficacy of an integrated cognitive training program, more research is needed to determine the utility of Mind Frontiers as a cognitive training tool.
Baniqued, Pauline L.; Ward, Nathan; Geyer, Alexandra; Kramer, Arthur F.
Although some studies have shown that cognitive training can produce improvements to untrained cognitive domains (far transfer), many others fail to show these effects, especially when it comes to improving fluid intelligence. The current study was designed to overcome several limitations of previous training studies by incorporating training expectancy assessments, an active control group, and “Mind Frontiers,” a video game-based mobile program comprised of six adaptive, cognitively demanding training tasks that have been found to lead to increased scores in fluid intelligence (Gf) tests. We hypothesize that such integrated training may lead to broad improvements in cognitive abilities by targeting aspects of working memory, executive function, reasoning, and problem solving. Ninety participants completed 20 hour-and-a-half long training sessions over four to five weeks, 45 of whom played Mind Frontiers and 45 of whom completed visual search and change detection tasks (active control). After training, the Mind Frontiers group improved in working memory n-back tests, a composite measure of perceptual speed, and a composite measure of reaction time in reasoning tests. No training-related improvements were found in reasoning accuracy or other working memory tests, nor in composite measures of episodic memory, selective attention, divided attention, and multi-tasking. Perceived self-improvement in the tested abilities did not differ between groups. A general expectancy difference in problem-solving was observed between groups, but this perceived benefit did not correlate with training-related improvement. In summary, although these findings provide modest evidence regarding the efficacy of an integrated cognitive training program, more research is needed to determine the utility of Mind Frontiers as a cognitive training tool. PMID:26555341
Brouillet, Denis; Vagnot, Caroline; Milhau, Audrey; Brunel, Lionel; Briglia, Johan; Versace, Rémy; Rousset, Stéphane
The aim of this study was to show that sensory-motor consequences of past actions form part of memory trace components cued by current experience. In a first task participants had to learn a list of words. Then in a guessing task they played against the computer. Finally, in a recognition task, they had to judge if the words were or were not present in the learning task. Words appeared either in the colour associated with success or failure in the guessing task, or in a non-informative colour. In the first experiment, results show that when the words to be judged were in the colour associated with success, participants answered faster and produced more "old" responses than when the words to be judged were in the colour associated with failure in the previous task. Moreover, when the words to be judged were in the colour associated with failure, participants were slower and produced less "old" responses than when the words were in a colour not informative of success or failure. The second experiment confirms that the results obtained in Experiment 1 were linked to the sensory-motor consequences of past actions associated with the colour and not to the colour itself.
Meir Drexler, Shira; Hamacher-Dang, Tanja C; Wolf, Oliver T
In extinction learning, the individual learns that a previously acquired association (e.g. between a threat and its predictor) is no longer valid. This learning is the principle underlying many cognitive-behavioral psychotherapeutic treatments, e.g. 'exposure therapy'. However, extinction is often highly-context dependent, leading to renewal (relapse of extinguished conditioned response following context change). We have previously shown that post-extinction stress leads to a more context-dependent extinction memory in a predictive learning task. Yet as stress prior to learning can impair the integration of contextual cues, here we aim to create a more generalized extinction memory by inducing stress prior to extinction. Forty-nine men and women learned the associations between stimuli and outcomes in a predictive learning task (day 1), extinguished them shortly after an exposure to a stress/control condition (day 2), and were tested for renewal (day 3). No group differences were seen in acquisition and extinction learning, and a renewal effect was present in both groups. However, the groups differed in the strength and context-dependency of the extinction memory. Compared to the control group, the stress group showed an overall reduced recovery of responding to the extinguished stimuli, in particular in the acquisition context. These results, together with our previous findings, demonstrate that the effects of stress exposure on extinction memory depend on its timing. While post-extinction stress makes the memory more context-bound, pre-extinction stress strengthens its consolidation for the acquisition context as well, making it potentially more resistant to relapse. These results have implications for the use of glucocorticoids as extinction-enhancers in exposure therapy. Copyright © 2017 Elsevier Inc. All rights reserved.
Wesley, Michael J; Lile, Joshua A; Fillmore, Mark T; Porrino, Linda J
Determining the neurobehavioral profiles that differentiate heavy drinkers who are and are not alcohol dependent will inform treatment efforts. Working memory is linked to substance use disorders and can serve as a representation of the demand placed on the neurophysiology associated with cognitive control. Behavior and brain activity (via fMRI) were recorded during an N-Back working memory task in controls (CTRL), nondependent heavy drinkers (A-ND) and dependent heavy drinkers (A-D). Typical and novel step-wise analyses examined profiles of working memory load and increasing task demand, respectively. Performance was significantly decreased in A-D during high working memory load (2-Back), compared to CTRL and A-ND. Analysis of brain activity during high load (0-Back vs. 2- Back) showed greater responses in the dorsal lateral and medial prefrontal cortices of A-D than CTRL, suggesting increased but failed compensation. The step-wise analysis revealed that the transition to Low Demand (0-Back to 1-Back) was associated with robust increases and decreases in cognitive control and default-mode brain regions, respectively, in A-D and A-ND but not CTRL. The transition to High Demand (1-Back to 2-Back) resulted in additional engagement of these networks in A-ND and CTRL, but not A-D. Heavy drinkers engaged working memory neural networks at lower demand than controls. As demand increased, nondependent heavy drinkers maintained control performance but relied on additional neurophysiological resources, and dependent heavy drinkers did not display further resource engagement and had poorer performance. These results support targeting these brain areas for treatment interventions. Copyright © 2017 Elsevier B.V. All rights reserved.
Moon, Chung-Man; Yang, Jong-Chul; Jeong, Gwang-Woo
The functional neuroanatomy for explicit memory in conjunction with the major anxiety symptoms in patients with generalized anxiety disorder (GAD) has not yet been clearly identified. To investigate the brain activation patterns on the interaction between emotional and cognitive function during the explicit memory tasks, as well as its correlation with clinical characteristics in GAD. The participants comprised GAD patients and age-matched healthy controls. The fMR images were obtained while the participants performed an explicit memory task with neutral and anxiety-inducing words. Patients showed significantly decreased functional activities in the putamen, head of the caudate nucleus, hippocampus, and middle cingulate gyrus during the memory tasks with the neutral and anxiety-inducing words, whereas the precentral gyrus and ventrolateral prefrontal cortex were significantly increased only in the memory tasks with the anxiety-inducing words. Also, the blood oxygenation level-dependent (BOLD) signal changes in the hippocampus were positively correlated with the recognition accuracy for both neutral and anxiety-inducing words. This study identified the brain areas associated with the interaction between emotional regulation and cognitive function in the explicit memory tasks in patients with GAD. These findings would be helpful to understand the neural mechanism on the explicit memory-related cognitive deficits and emotional dysfunction with GAD symptoms. © The Foundation Acta Radiologica 2016.
Mahy, Caitlin E. V.; Moses, Louis J.
The current study examined the impact of retention interval task difficulty on 4- and 5-year-olds' prospective memory (PM) to test the hypothesis that children periodically monitor their intentions during the retention interval and that disrupting this monitoring may result in poorer PM performance. In addition, relations among PM, working memory,…
Hernandez, Mireia; Costa, Albert; Humphreys, Glyn W.
We ask whether bilingualism aids cognitive control over the inadvertent guidance of visual attention from working memory and from bottom-up cueing. We compare highly-proficient Catalan-Spanish bilinguals with Spanish monolinguals in three visual search conditions. In the working memory (WM) condition, attention was driven in a top-down fashion by…
Zhang, Wen-Hua; Williams, Ziv M.
Once a memory has formed, it is thought to undergo a gradual transition within the brain from short- to long-term storage. This putative process, however, also poses a unique problem to the memory system in that the same learned items must also be retrieved across broadly varying time scales. Here, we find that neurons in the ventrolateral…
Willebrand, Mimmie; Norlund, Fredrika; Kildal, Morten; Gerdin, Bengt; Ekselius, Lisa; Andersson, Gerhard
The aim of the study was to explore cognitive distortions in recovered burn patients. Previous studies in trauma patients have shown trauma-specific attentional bias, long response latencies, and deficits in memory specificity. Eighteen former patients, burn injured 5-19 years ago and 18 matched controls performed the emotional Stroop task, including burn and general trauma-related words, and the autobiographical memory test (AMT). In addition, verbal fluency, life events, and current mood were assessed. Regarding the Stroop task, the recovered patients had longer response latencies to burn words than to neutral and trauma words, a difference not seen in the control subjects. Regarding the AMT, the memory specificity did not differ between the groups. Overall, the former patients had longer latencies than the controls and poorer verbal fluency. The present study showed that recovered burn patients display a moderate Stroop effect, i.e. an attentional bias, in spite of the fact that the injury occurred several years before the testing. This may imply that the recovered burn patients consider the burn an important issue in life. The post-burn patients also presented signs of a slight cognitive slowness as compared to the controls. This finding deserves further attention in the rehabilitation of burn patients.
Pu, Shenghong; Nakagome, Kazuyuki; Yamada, Takeshi; Itakura, Masashi; Yamanashi, Takehiko; Yamada, Sayaka; Masai, Mieko; Miura, Akihiko; Yamauchi, Takahira; Satake, Takahiro; Iwata, Masaaki; Nagata, Izumi; Roberts, David L; Kaneko, Koichi
Social cognition is an important determinant of functional impairment in schizophrenia, but its relationship with the prefrontal functional abnormalities associated with the condition is still unclear. The present study aimed to explore the relationship between social cognition and prefrontal function in patients with schizophrenia using 52-channel near-infrared spectroscopy (NIRS). Twenty-six patients with schizophrenia and 26 age-, gender-, and intelligence quotient-matched healthy controls (HCs) participated in the study. Hemodynamic responses in the prefrontal and superior temporal cortical regions were assessed during a working memory task using NIRS. Social cognition was assessed using the Social Cognition Screening Questionnaire (SCSQ). The observed hemodynamic responses were significantly reduced in the lateral prefrontal cortex (PFC), the frontopolar cortex, and temporal regions in subjects with schizophrenia compared to HCs. Additionally, lateral PFC hemodynamic responses assessed during the working memory task demonstrated a strong positive correlation with the SCSQ theory of mind (ToM) subscale score even after controlling for working memory performance. These results suggest that ToM integrity is closely related to lateral PFC functional abnormalities found in patients with schizophrenia. In addition, this study provides evidence to suggest that NIRS could be used to identify biomarkers of social cognition function in subjects with schizophrenia.
Dall, Jonas Olsen; Watanabe, Katsumi; Sørensen, Thomas Alrik
We explore whether expertise can modulate the capacity of visual short-term memory, as some seem to argue that training affects capacity of short-term memory  while others are not able to find this modulation . We extend on a previous study  demonstrating expertise effects...... are in line with the theoretical interpretation that visual short-term memory reflects the sum of the reverberating feedback loops to representations in long-term memory.......), and expert observers (Japanese university students). For both the picture and the letter condition we find no performance difference in memory capacity, however, in the critical hiragana condition we demonstrate a systematic difference relating expertise differences between the groups. These results...
Bäumler, Damaris; Kliegel, Matthias; Kirschbaum, Clemens; Miller, Robert; Alexander, Nina; Stalder, Tobias
Activation of prospective memory (PM) representations following awakening has been proposed to modulate expression of the cortisol awakening response (CAR). However, experimental testing of this hypothesis is still missing. This study examined the effect of a naturalistic PM-related manipulation on the CAR in a sample of 35 preschool-aged children. The CAR was assessed on two study days (0 and 30min post-awakening) using objective verification of awakening and sampling times. Children had to remember to perform a naturalistic PM-related task (reminding their parents about a gift) on the experimental day while there was no intervention on the control day (counterbalanced order). Results revealed an increased CAR on the experimental day (mean±SD increase: 9.97±7.05nmol/L) compared to the control day (mean±SD increase: 5.45±8.14nmol/L; p=.022). Our findings concur with the notion that expression of the CAR is modulated by post-awakening anticipatory processes involving activation of PM representations. Copyright © 2014 Elsevier B.V. All rights reserved.
Larsen, Lisbeth Hoejkjaer; Zibrandtsen, Ivan Chrilles; Wienecke, Troels
The functional relevance of cortical reorganisation post-stroke is still not well understood. In this study we investigated task-specific modulation of cortical connectivity between neural oscillations in key motor regions during the early phase after stroke. EEG and EMG recordings were examined...... from 15 patients and 18 controls during a precision grip task using the affected hand. Each patient attended two sessions in the acute and subacute phase (median of 3 & 34 days) post-stroke. Dynamic causal modeling (DCM) for induced responses was used to investigate task-specific modulations......). Bayesian model selection favoured a fully connected model. A reduced coupling from SMA and intact M1 in the γ-band (31-48 Hz) to lesioned M1 in the β-band (15-30 Hz) was observed in patients in the acute phase compared to controls. Behavioral performance improved significantly in the subacute phase while...
Bai, Feng; Yuan, Yonggui; Yu, Hui; Zhang, Zhijun
Social-cognitive processing has been posited to underlie general functions such as episodic memory. Episodic memory impairment is a recognized hallmark of amnestic mild cognitive impairment (aMCI) who is at a high risk for dementia. Three canonical networks, self-referential processing, executive control processing and salience processing, have distinct roles in episodic memory retrieval processing. It remains unclear whether and how these sub-networks of the episodic memory retrieval system would be affected in aMCI. This task-state fMRI study constructed systems-level episodic memory retrieval sub-networks in 28 aMCI and 23 controls using two computational approaches: a multiple region-of-interest based approach and a voxel-level functional connectivity-based approach, respectively. These approaches produced the remarkably similar findings that the self-referential processing network made critical contributions to episodic memory retrieval in aMCI. More conspicuous alterations in self-referential processing of the episodic memory retrieval network were identified in aMCI. In order to complete a given episodic memory retrieval task, increases in cooperation between the self-referential processing network and other sub-networks were mobilized in aMCI. Self-referential processing mediate the cooperation of the episodic memory retrieval sub-networks as it may help to achieve neural plasticity and may contribute to the prevention and treatment of dementia. Copyright © 2016 Elsevier B.V. All rights reserved.
Gallo, David A; Kensinger, Elizabeth A; Schacter, Daniel L
According to the distinctiveness heuristic, subjects rely more on detailed recollections (and less on familiarity) when memory is tested for pictures relative to words, leading to reduced false recognition. If so, then neural regions that have been implicated in effortful postretrieval monitoring (e.g., dorsolateral prefrontal cortex) might be recruited less heavily when trying to remember pictures. We tested this prediction with the criterial recollection task. Subjects studied black words, paired with either the same word in red font or a corresponding colored picture. Red words were repeated at study to equate recognition hits for red words and pictures. During fMRI scanning, alternating red word memory tests and picture memory tests were given, using only white words as test stimuli (say "yes" only if you recollect a corresponding red word or picture, respectively). These tests were designed so that subjects had to rely on memory for the criterial information. Replicating prior behavioral work, we found enhanced rejection of lures on the picture test compared to the red word test, indicating that subjects had used a distinctiveness heuristic. Critically, dorsolateral prefrontal activity was reduced when rejecting familiar lures on the picture test, relative to the red word test. These findings indicate that reducing false recognition via the distinctiveness heuristic is not heavily dependent on frontally mediated postretrieval monitoring processes.
Gould, Kristy L; Ort, Amy J; Kamil, Alan C
What-where-when (WWW) memory during cache recovery was investigated in six Clark's nutcrackers. During caching, both red- and blue-colored pine seeds were cached by the birds in holes filled with sand. Either a short (3 day) retention interval (RI) or a long (9 day) RI was followed by a recovery session during which caches were replaced with either a single seed or wooden bead depending upon the color of the cache and length of the retention interval. Knowledge of what was in the cache (seed or bead), where it was located, and when the cache had been made (3 or 9 days ago) were the three WWW memory components under investigation. Birds recovered items (bead or seed) at above chance levels, demonstrating accurate spatial memory. They also recovered seeds more than beads after the long RI, but not after the short RI, when they recovered seeds and beads equally often. The differential recovery after the long RI demonstrates that nutcrackers may have the capacity for WWW memory during this task, but it is not clear why it was influenced by RI duration.
Zhou, Yong-Di; Fuster, Joaquín M
Neurons in the monkey's anterior parietal cortex (Brodmann's areas 3a, 3b, 1, and 2) have been reported to retain information from a visual cue that has been associated with a tactile stimulus in a haptic memory task. This cross-modal transfer indicates that neurons in somatosensory cortex can respond to non-tactile stimuli if they are associated with tactile information needed for performance of the task. We hypothesized that neurons in somatosensory cortex would be activated by other non-tactile stimuli signaling the haptic movements--of arm and hand--that the task required. We found such cells in anterior parietal areas. They reacted with short-latency activity changes to an auditory signal (a click) that prompted those movements. Further, some of those cells changed their discharge in temporal correlation with the movements themselves, with the touch of the test objects, and with the short-term memory of those objects for subsequent tactile discrimination. These findings suggest that cells in the somatosensory cortex participate in the behavioral integration of auditory stimuli with other sensory stimuli and with motor acts that are associated with those stimuli.
Full Text Available The dopaminergic system is known to be involved in working memory processed by several brain regions like prefrontal cortex (PFC, hippocampus, striatum. In an earlier study we could show that Levodopa but not Modafinil enhanced working memory in a T-maze only during the early phase of training (day 3, whereas the later phase remained unaffected. Rats treated with a higher dose performed better than low dose treated rats. Here we could more specifically segregate the contributions of dopamine type 1- and 2- like receptors (D1R; D2R to the training state dependent modulation of spatial working memory by intracerebroventricular (ICV application of a D1R-like (SKF81297 and D2R-like agonist (Sumanirole and antagonist (SCH23390, Remoxipride at a low and high dose through 3 days of training. The D1R-like-agonist at both doses enhanced working memory at day 1 but only in the low dose treated rats enhancement persists over training compared to control rats. Rats treated with a high dose of a D1R-like-antagonist show persistent enhancement of working memory over training, whereas in low dose treated rats no statistical difference at any time point could be determined compared to controls. The D2R-like-agonist at both doses does not show an effect at any time point when compared to control animals, whereas the D2R-like antagonist at a low dose enhanced working memory at day 2. For the most effective D1R-like agonist, we repeated the experiments in a water maze working memory task, to test for task dependent differences in working memory modulations. Treated rats at both doses did not differ as compared to controls, but the temporal behavioral performance of all groups was different compared to T-maze trained rats. The results are in line with the view that spatial working memory is optimized within a limited range of dopaminergic transmission, however suggest that these ranges vary during spatial training.
Stephanie L. Gage
Full Text Available Nitric oxide (NO is thought to play an important neuromodulatory role in the olfactory system. This modulation has been suggested to be particularly important for olfactory learning and memory in the antennal lobe (the primary olfactory network in invertebrates. We are using the hawkmoth, Manduca sexta, to further investigate the role of NO in olfactory memory. Recent findings suggest that NO affects short-term memory traces and that NO concentration fluctuates with the light cycle. This gives rise to the hypothesis that NO may be involved in the connection between memory and circadian rhythms. In this study, we explore the role of diurnal time and NO in memory by altering the time of day when associative-olfactory conditioning is performed. We find a strong effect of NO on short-term memory, and two surprising effects of diurnal time. We find that (1 at certain time points, NO affects longer traces of memory in addition to short-term memory, and (2 when conditioning is performed close to the light cycle switches—both from light to dark and dark to light—NO does not significantly affect memory at all. These findings suggest an intriguing functional role for NO in olfactory conditioning that is modulated as a function of diurnal time.
Kim, Dong Hyun; Kim, Jong Min; Park, Se Jin; Lee, Seungheon; Shin, Chan Young; Cheong, Jae Hoon; Ryu, Jong Hoon
Available evidence strongly suggests that the γ-aminobutyric acid type A (GABA(A)) receptor has a crucial role in memory retrieval. However, the signaling mechanisms underlying the role of GABA(A) receptor modulation in memory retrieval are unclear. We conducted one-trial passive avoidance task with pre-retention trial drug administration in the hippocampus to test the effects of GABA(A) receptor modulation on memory retrieval. We further tested the co-involvement of signaling molecules: extracellular signal-regulated kinase (ERK), Ca(2+)/calmodulin-dependent protein kinase II (CaMKII), and cAMP responsive element-binding protein (CREB). First, we observed that the phosphorylation of hippocampal ERK was required for memory retrieval during the task. Accordingly, to investigate whether GABA(A) receptor activation or inhibition induces ERK phosphorylation during memory retrieval, drugs that target the GABA(A) receptor were administered into the hippocampus before the retention trial. Muscimol, a GABA(A) receptor agonist, and diazepam, an agonist to benzodiazepine-binding site of GABA(A) receptor, blocked retention trial-induced ERK phosphorylation and impaired memory retrieval. Furthermore, co-treatment with sub-effective dose of U0126, a mitogen-activated protein kinase inhibitor, blocked the upregulation of ERK phosphorylation and impaired memory retrieval, and bicuculline methiodide (BMI), a GABA(A) receptor antagonist, increased ERK phosphorylation induced by the retention trial and facilitated memory retrieval. Finally, the effects of BMI were blocked by the co-application of a sub-effective dose of U0126. These results suggest that GABA(A) receptor-mediated memory retrieval is closely related to ERK activity.
Bodner, M; Shafi, M; Zhou, Y-D; Fuster, J M
Abstract Cells in the somatosensory cortex of the monkey are known to exhibit sustained elevations of firing frequency during the short-term mnemonic retention of tactile information in a haptic delay task. In this study, we examine the possibility that those firing elevations are accompanied by changes in firing pattern. Patterns are identified by the application of a pattern-searching algorithm to the interspike intervals of spike trains. By sequential use of sets of pattern templates with a range of temporal resolutions, we find patterned activity in the majority of the cells investigated. In general, the degree of patterning significantly increases during active memory. Surrogate analysis suggests that the observed patterns may not be simple linear stochastic functions of instantaneous or average firing frequency. Therefore, during the active retention of a memorandum, the activity of a 'memory cell' may be characterized not only by changes in frequency but also by changes in pattern.
Full Text Available It is now established that vitamin A and its derivatives, retinoic acid (RA, are required for cognitive functions in adulthood. RA hyposignaling and hyperactivity of glucocorticoid (GC pathway appear concomitantly during ageing and would contribute to the deterioration of hippocampal synaptic plasticity and functions. Furthermore, recent data have evidenced counteracting effects of retinoids on GC signaling pathway. In the present study, we addressed the following issue: whether the stimulation of RA pathway could modulate intrahippocampal corticosterone (CORT levels in middle-aged mice and thereby impact on hippocampal plasticity and cognitive functions. We firstly investigated the effects of vitamin A supplementation and RA treatment in middle-aged mice, on contextual serial discrimination task (CSD, a paradigm which allows the detection of early signs of age-related hippocampal-dependent memory dysfunction. We then measured intrahippocampal CORT concentrations by microdialysis before and after a novelty-induced stress. Our results show that both RA treatment and vitamin A supplementation improve episodic-like memory in middle-aged mice but RA treatment appears to be more efficient. Moreover, we show that the beneficial effect of RA on memory is associated to an increase in hippocampal PSD-95 expression. In addition, intrahippocampal CORT levels are reduced after novelty-induced stress in RA treated animals. This effect cannot be related to a modulation of hippocampal 11β-HSD1 expression. In addition, RA treatment induces a modulation of retinoic acid receptors RARα and RARβ expression in middle-aged mice, a finding which has been correlated with the amplitude of intrahippocampal CORT levels after novelty-induced stress. Taken together, our results suggest that the preventive action of RA treatment on age-related memory deficits in middle-aged mice could be, at least in part, due to an inhibitory effect of retinoids on glucocorticoid
Full Text Available Long-term potentiation (LTP is the enhancement of postsynaptic responses for hours, days or weeks following the brief repetitive afferent stimulation of presynaptic afferents. It has been proposed many times over the last 30 years to be the basis of long-term memory. Several recent findings finally supported this hypothesis: a memory formation of one-trial avoidance learning depends on a series of molecular steps in the CA1 region of the hippocampus almost identical to those of LTP in the same region; bhippocampal LTP in this region accompanies memory formation of that task and of another similar task. However, CA1 LTP and the accompanying memory processes can be dissociated, and in addition plastic events in several other brain regions(amygdala, entorhinal cortex, parietal cortex are also necessary for memory formation of the one-trial task, and perhaps of many others.A potenciação de longa duração (LTP é o aumento de respostas pós-sinápticas durante horas, dias ou semanas após a breve estimulação repetitiva de aferentes pre-sinápticos. Foi proposto durante 30 anos ser a base da memória de longa duração. Vários achados recentes finalmente apoiaram esta hipótese: a a formação da memória de esquiva inibitória adquirida numa sessão depende de uma cadeia de processos moleculares na região CA1 do hipocampo quase idêntica à da LTP nessa mesma região; b LTP hipocampal nessa região acompanha a formação da memóría dessa tarefa e de outra semelhante. No entanto, a LTP de CA1 e os processos de memória podem ser dissociados e, fora disso, processos plásticos em outras regiões cerebrais (amígdala, córtex entorrinal, córtex parietal também são necessários para a formação da memória da tarefa de uma sessão e talvez de muitas outras.
McVay, Jennifer C.; Kane, Michael J.
On the basis of the executive-attention theory of working memory capacity (WMC; e.g., M. J. Kane, A. R. A. Conway, D. Z. Hambrick, & R. W. Engle, 2007), the authors tested the relations among WMC, mind wandering, and goal neglect in a sustained attention to response task (SART; a go/no-go task). In 3 SART versions, making conceptual versus…
Lawton, B. W.
An investigation has been made to determine the effects of noise on human performance. Fourteen subjects performed a memory-decision-response task in relative quiet and while listening to tape recorded noises. Analysis of the data obtained indicates that performance was degraded in the presence of noise. Significant increases in problem solution times were found for impulsive noise conditions as compared with times found for the no-noise condition. Performance accuracy was also degraded. Significantly more error responses occurred at higher noise levels; a direct or positive relation was found between error responses and noise level experienced by the subjects.
Beran, Michael J; Perdue, Bonnie M; Futch, Sara E; Smith, J David; Evans, Theodore A; Parrish, Audrey E
Three chimpanzees performed a computerized memory task in which auditory feedback about the accuracy of each response was delayed. The delivery of food rewards for correct responses also was delayed and occurred in a separate location from the response. Crucially, if the chimpanzees did not move to the reward-delivery site before food was dispensed, the reward was lost and could not be recovered. Chimpanzees were significantly more likely to move to the dispenser on trials they had completed correctly than on those they had completed incorrectly, and these movements occurred before any external feedback about the outcome of their responses. Thus, chimpanzees moved (or not) on the basis of their confidence in their responses, and these confidence movements aligned closely with objective task performance. These untrained, spontaneous confidence judgments demonstrated that chimpanzees monitored their own states of knowing and not knowing and adjusted their behavior accordingly. Copyright © 2015 Elsevier B.V. All rights reserved.
Beran, Michael J.; Perdue, Bonnie M.; Futch, Sara E.; Smith, J. David; Evans, Theodore A.; Parrish, Audrey E.
Three chimpanzees performed a computerized memory task in which auditory feedback about the accuracy of each response was delayed. The delivery of food rewards for correct responses was also delayed and occurred in a separate location from the response. Crucially, if the chimpanzees did not move to the reward-delivery site before food was dispensed, the reward was lost and could not be recovered. Chimpanzees were significantly more likely to move to the dispenser on trials they had completed correctly than on those they had completed incorrectly, and these movements occurred before any external feedback about the outcome of their responses. Thus, chimpanzees moved (or not) on the basis of their confidence in their responses, and these confidence movements aligned closely with objective task performance. These untrained, spontaneous confidence judgments demonstrated that chimpanzees monitored their own states of knowing and not knowing and adjusted their behavior accordingly. PMID:26057831
Full Text Available Prefrontal cortex activity has been associated with changes to heart rate variability (HRV via mediation of the cortico-subcortical pathways that regulate the parasympathetic and sympathetic branches of the autonomic nervous system. Changes in HRV due to altered prefrontal cortex functioning can be predicted using the neurovisceral integration model, which suggests that prefrontal hyperactivity increases parasympathetic tone and decreases contributions from the sympathetic nervous system. Working memory (WM tasks and transcranial direct current stimulation (tDCS have been used independently to modulate brain activity demonstrating changes to HRV in agreement with the model. We investigated the combined effects of prefrontal tDCS and a WM task on HRV. Bifrontal tDCS was administered for 15 minutes at 2mA to 20 participants in a sham controlled, single-blind study using parallel groups. A WM task was completed by participants at three time points; pre-, during-, and post-tDCS, with resting state data collected at similar times. Frequency-domain HRV was computed for high frequency (HF; 0.15-0.4Hz and low frequency (LF; 0.04-0.15Hz power reflecting parasympathetic and sympathetic branch activity, respectively. Response time on the WM task, but not accuracy, improved from baseline to during-tDCS and post-tDCS with sham, but not active, stimulation. HF-HRV was significantly increased in the active tDCS group compared to sham, lasting beyond cessation of stimulation. Additionally, HF-HRV showed a task-related reduction in power during performance on the WM task. Changes in LF-HRV were moderately inversely correlated (r > 0.4 with changes in WM accuracy during and following tDCS compared to baseline levels. Stimulation of the prefrontal cortex resulted in changes to the parasympathetic branch of the nervous system in agreement with a linearly additive interpretation of effects. Sympathetic activity was not directly altered by tDCS, but was correlated
Kessler, Yoav; Meiran, Nachshon
Previous studies claimed that task representation is carried out by the activated long-term memory portion of working memory (WM; Meiran and Kessler in J Exp Psychol Human Percept Perform 34:137-157, 2008). The present study provides a more direct support for this hypothesis. We used the reaction-time task-rule congruency effect (RT-TRCE) in a task-switching setup, and tested the effects of loading WM with irrelevant task rules on RT-TRCE. Experiment 1 manipulated WM load in a between-subject design. WM participants performed a color/shape task switching, while having 0, 1 or 3 numerical task rules as WM load. Experiment 2 used a similar load manipulation (1 or 3 rules to load WM) in a within-subject design. Experiment 3 extended these results by loading WM with perceptual tasks that were more similar to the shape/color tasks. The results show that RT-TRCE was not affected by WM load supporting the activated long-term memory hypothesis.
Full Text Available Spontaneous low-frequency Blood-Oxygenation Level-Dependent (BOLD signals acquired during resting state are characterized by spatial patterns of synchronous fluctuations, ultimately leading to the identification of robust brain networks. The resting-state brain networks, including the Default Mode Network (DMN, are demonstrated to persist during sustained task execution, but the exact features of task-related changes of network properties are still not well characterized. In this work we sought to examine in a group of 20 healthy volunteers (age 33 ± 6 years, 8 F/12 M the relationship between changes of spectral and spatiotemporal features of one prominent resting-state network, namely the DMN, during the continuous execution of a working memory n-back task. We found that task execution impacted on both functional connectivity and amplitude of BOLD fluctuations within large parts of the DMN, but these changes correlated between each other only in a small area of the posterior cingulate. We conclude that combined analysis of multiple parameters related to connectivity, and their changes during the transition from resting state to continuous task execution, can contribute to a better understanding of how brain networks rearrange themselves in response to a task.
Tommasin, Silvia; Mascali, Daniele; Gili, Tommaso; Assan, Ibrahim Eid; Moraschi, Marta; Fratini, Michela; Wise, Richard G.; Macaluso, Emiliano; Mangia, Silvia; Giove, Federico
Spontaneous low-frequency Blood-Oxygenation Level-Dependent (BOLD) signals acquired during resting state are characterized by spatial patterns of synchronous fluctuations, ultimately leading to the identification of robust brain networks. The resting-state brain networks, including the Default Mode Network (DMN), are demonstrated to persist during sustained task execution, but the exact features of task-related changes of network properties are still not well characterized. In this work we sought to examine in a group of 20 healthy volunteers (age 33 ± 6 years, 8 F/12 M) the relationship between changes of spectral and spatiotemporal features of one prominent resting-state network, namely the DMN, during the continuous execution of a working memory n-back task. We found that task execution impacted on both functional connectivity and amplitude of BOLD fluctuations within large parts of the DMN, but these changes correlated between each other only in a small area of the posterior cingulate. We conclude that combined analysis of multiple parameters related to connectivity, and their changes during the transition from resting state to continuous task execution, can contribute to a better understanding of how brain networks rearrange themselves in response to a task. PMID:28845420
Tommasin, Silvia; Mascali, Daniele; Gili, Tommaso; Eid Assan, Ibrahim; Moraschi, Marta; Fratini, Michela; Wise, Richard G.; Macaluso, Emiliano; Mangia, Silvia; Giove, Federico
Spontaneous low-frequency Blood-Oxygenation Level-Dependent (BOLD) signals acquired during resting state are characterized by spatial patterns of synchronous fluctuations, ultimately leading to the identification of robust brain networks. The resting-state brain networks, including the Default Mode Network (DMN), are demonstrated to persist during sustained task execution, but the exact features of task-related changes of network properties are still not well characterized. In this work we sought to examine in a group of 20 healthy volunteers (age 33±6 years, 8F/12M) the relationship between changes of spectral and spatiotemporal features of one prominent resting-state network, namely the DMN, during the steady-state execution of a sustained working memory n-back task. We found that the steady state execution of such a task impacted on both functional connectivity and amplitude of BOLD fluctuations within large parts of the DMN, but these changes correlated between each other only in a small area of the posterior cingulate. We conclude that combined analysis of multiple parameters related to connectivity, and their changes during the transition from resting state to steady-state task execution, can contribute to a better understanding of how brain networks rearrange themselves in response of a task.
Blinowska, Katarzyna J; Kaminski, Maciej; Kaminski, Jan; Brzezicka, Aneta
We studied the dynamical pattern of transmission involved in the information processing during cognitive experiments engaging working memory. The ensemble averaging approach was used to fit a multichannel autoregressive model to the EEG signals recorded during the transitive reasoning task. The short-time directed transfer function was estimated for finding dynamical patterns of functional connectivity during the memory and reasoning task. The results indicated that there exist particular areas where information is processed as envisaged by transmissions between closely located electrodes. In case of reasoning task these local circuits were located in frontal and parietal regions. These areas (these local circuits) from time to time exchange information between each other‥
Vandenberghe, M; Michiels, J; Vanderaspoilden, V; Claes, T; Fery, P
Early damage to episodic memory encoding and consolidation processes has been demonstrated in dementia of the Alzheimer type. However, in the domain of verbal episodic memory assessment, there are few diagnostic tools adapted to the old and oldest old as far as ease of administration and accuracy of normative data are concerned. Classic tasks are either too effortful (like the free recall/cued recall of 16 items), not sensitive enough (like the 5 words test), or insufficiently accurate for people above 70 years old in terms of normative data. The aim of this study was to develop a reduced task (in terms of number of items and number of trials) assessing verbal episodic memory in people aged between 70 and 89 years old. The task (GERIA-12) used the same procedure as the RL/RI-16 task but the list comprised only 12 words and there were only 2 learning trials. In order to assess consolidation processes, we included 2 delayed recall trials, one after 20 minutes and the other after 24 hours. We also calculated indexes adapted from the Item-Specific Deficit Approach developed by Wright et al., which has the advantage of providing measures specific to encoding, consolidation and retrieval processes. Standardization was done with data from 220 people aged between 70 and 89 years old and belonging to 3 education levels. We obtained a significant effect of age and education level: scores decrease with age and increase with education. Norms have thus been calculated taking those two variables into consideration. Concerning the standardization, Barona method has been used for free recall scores while percentiles have been used for all other scores (total recall, free recall, encoding, consolidation and retrieval indexes). Normative data are also provided for intrusions and perseverations. This new task allows encoding, consolidation and retrieval processes assessment in older people and has the following advantages: the procedure is more suitable (ease and time of
van Ede, Freek; Jensen, Ole; Maris, Eric
Flexible control over currently relevant sensory representations is an essential feature of primate cognition. We investigated the neurophysiological bases of such flexible control in humans during an intermodal working memory task in which participants retained visual or tactile sequences. Using magnetoencephalography, we first show that working memory retention engages early visual and somatosensory areas, as reflected in the sustained load-dependent suppression of alpha and beta oscillations. Next, we identify three components that are also load dependent but modality independent: medial prefrontal theta synchronization, frontoparietal gamma synchronization, and sustained parietal event-related fields. Critically, these domain-general components predict (across trials and within load conditions) the modality-specific suppression of alpha and beta oscillations, with largely unique contributions per component. Thus, working memory engages multiple complementary frontoparietal components that have discernible neuronal dynamics and that flexibly modulate retention-related activity in sensory areas in a manner that tracks the current contents of working memory.
Guo, Zhiqiang; Wu, Xiuqin; Li, Weifeng; Jones, Jeffery A; Yan, Nan; Sheft, Stanley; Liu, Peng; Liu, Hanjun
Although working memory (WM) is considered as an emergent property of the speech perception and production systems, the role of WM in sensorimotor integration during speech processing is largely unknown. We conducted two event-related potential experiments with female and male young adults to investigate the contribution of WM to the neurobehavioural processing of altered auditory feedback during vocal production. A delayed match-to-sample task that required participants to indicate whether the pitch feedback perturbations they heard during vocalizations in test and sample sequences matched, elicited significantly larger vocal compensations, larger N1 responses in the left middle and superior temporal gyrus, and smaller P2 responses in the left middle and superior temporal gyrus, inferior parietal lobule, somatosensory cortex, right inferior frontal gyrus, and insula compared with a control task that did not require memory retention of the sequence of pitch perturbations. On the other hand, participants who underwent extensive auditory WM training produced suppressed vocal compensations that were correlated with improved auditory WM capacity, and enhanced P2 responses in the left middle frontal gyrus, inferior parietal lobule, right inferior frontal gyrus, and insula that were predicted by pretraining auditory WM capacity. These findings indicate that WM can enhance the perception of voice auditory feedback errors while inhibiting compensatory vocal behavior to prevent voice control from being excessively influenced by auditory feedback. This study provides the first evidence that auditory-motor integration for voice control can be modulated by top-down influences arising from WM, rather than modulated exclusively by bottom-up and automatic processes. SIGNIFICANCE STATEMENT One outstanding question that remains unsolved in speech motor control is how the mismatch between predicted and actual voice auditory feedback is detected and corrected. The present study
Full Text Available A new tablet device version (IOS platform of the Spatial Delayed Recognition Span Task (SDRST was developed with the aim of investigating visuospatial Working Memory (WM abilities based on touchscreen technology. This new WM testing application will be available to download for free in Apple Store app (SDRST app. In order to verify the feasibility of this computer-based task, we conducted three experiments with different manipulations and groups of participants. We were interested in investigating if (1 the SDRST is sensitive enough to tap into cognitive differences brought by ageing and dementia; (2 different experimental manipulations work successfully; (3 cortical brain activations seen in other WM tasks are also demonstrated here; and (4 non-human primates are able to answer the task. Performance (scores and response time was better for young than older adults and higher for the latter when compared to Alzheimer’s disease patients. All groups performed better with facial stimuli than with images of scenes and with emotional than with neutral stimuli. Electrophysiology data showed activation on prefrontal and frontal areas of scalp, theta band activity on the midline area, and gamma activity in left temporal area. There are all scalp regions known to be related to attention and WM. Besides those data, our sample of adult captive capuchin monkeys (Sapajus libidinosus answered the task above chance level. Taken together, these results corroborate the reliability of this new computer-based SDRST as a measure of visuospatial WM in clinical and non-clinical populations as well as in non-human primates. Its tablet app allows the task to be administered in a wide range of settings, including hospitals, homes, schools, laboratories, universities, and research institutions.
Mélanie F Guigueno
Full Text Available Spatial cognition in females and males can differ in species in which there are sex-specific patterns in the use of space. Brown-headed cowbirds are brood parasites that show a reversal of sex-typical space use often seen in mammals. Female cowbirds, search for, revisit and parasitize hosts nests, have a larger hippocampus than males and have better memory than males for a rewarded location in an open spatial environment. In the current study, we tested female and male cowbirds in breeding and non-breeding conditions on a touchscreen delayed-match-to-sample task using both spatial and colour stimuli. Our goal was to determine whether sex differences in spatial memory in cowbirds generalizes to all spatial tasks or is task-dependant. Both sexes performed better on the spatial than on the colour touchscreen task. On the spatial task, breeding males outperformed breeding females. On the colour task, females and males did not differ, but females performed better in breeding condition than in non-breeding condition. Although female cowbirds were observed to outperform males on a previous larger-scale spatial task, males performed better than females on a task testing spatial memory in the cowbirds' immediate visual field. Spatial abilities in cowbirds can favour males or females depending on the type of spatial task, as has been observed in mammals, including humans.
Guigueno, Mélanie F.; MacDougall-Shackleton, Scott A.; Sherry, David F.
Spatial cognition in females and males can differ in species in which there are sex-specific patterns in the use of space. Brown-headed cowbirds are brood parasites that show a reversal of sex-typical space use often seen in mammals. Female cowbirds, search for, revisit and parasitize hosts nests, have a larger hippocampus than males and have better memory than males for a rewarded location in an open spatial environment. In the current study, we tested female and male cowbirds in breeding and non-breeding conditions on a touchscreen delayed-match-to-sample task using both spatial and colour stimuli. Our goal was to determine whether sex differences in spatial memory in cowbirds generalizes to all spatial tasks or is task-dependant. Both sexes performed better on the spatial than on the colour touchscreen task. On the spatial task, breeding males outperformed breeding females. On the colour task, females and males did not differ, but females performed better in breeding condition than in non-breeding condition. Although female cowbirds were observed to outperform males on a previous larger-scale spatial task, males performed better than females on a task testing spatial memory in the cowbirds’ immediate visual field. Spatial abilities in cowbirds can favour males or females depending on the type of spatial task, as has been observed in mammals, including humans. PMID:26083573
Henckens, Marloes J. A. G.; van Wingen, Guido A.; Joëls, Marian; Fernández, Guillén
Corticosteroids are potent modulators of human higher cognitive function. They are released in response to stress, and are thought to be involved in the modulation of cognitive function by inducing distinct rapid nongenomic, and slow genomic changes, affecting neural plasticity throughout the brain.
Ming-I Brandon Lin
Full Text Available BackgroundIncreasing evidence suggests that walking while performing a concurrent task negatively influences gait performance. However, it remains unclear how higher-level cognitive processes and coordination of limb movements are altered in challenging walking environments. This study investigated the influence of cognitive task complexity and walking road condition on the neutral correlates of executive function and postural control in dual-task walking. MethodsTwenty-four healthy young adults completed a series of overground walks with three walking road conditions (wide, narrow, with obstacles with and without the concurrent n-back working memory tasks of two complexity levels (1-back and 3-back. Prefrontal brain activation was assessed by functional near-infrared spectroscopy. A three-dimensional motion analysis system was used simultaneously to measure gait performance and lower-extremity kinematics. Repeated measures analysis of variance were performed to examine the differences between the conditions. ResultsIn comparison with standing still, participants showed lower n-back task accuracy while walking, with the worst performance from the road with obstacles. Spatiotemporal gait parameters, lower-extremity joint movements, and the relative changes in oxygenated hemoglobin (HbO concentration levels were all significantly different across the task complexity and walking path conditions. While dual-tasking participants were found to flex their hips and knees less, leading to a slower gait speed, longer stride time, shorter step length, and greater gait variability than during normal walking. For narrow-road walking, smaller ankle dorsiflexion and larger hip flexion were observed, along with a reduced gait speed. Obstacle negotiation was mainly characterized by increased gait variability than other conditions. HbO levels appeared to be lower during dual-task walking than normal walking. Compared to wide and obstacle conditions, walking on
Akpinar, Selcuk; Popović, Stevo; Kirazci, Sadettin
The purpose of this study was to analyze the effect of two different types of feedback on a spatial memory task between the blind and blindfolded-sighted participants. Participants tried to estimate the predetermined distance by using their dominant hands. Both blind and blindfolded-sighted groups were randomly divided into two feedback subgroups as "100% frequency" and "10% bandwidth". The score of the participants was given verbally to the participants as knowledge of results (KR). The target distance was set as 60 cm. Sixty acquisition trials were performed in 4 sets each including 15 repetition afterwards immediate and delayed retention tests were undertaken. Moreover, 24 hours past the delayed retention test, the participants completed 15 no-KR trials as a transfer test (target distance was 30 cm). The results of the statistical analyses revealed no significant differences for both acquisition and retention tests. However, a significant difference was found at transfer test. 100% frequency blind group performed significantly less accurate than all other groups. As a result, it can be concluded that different types of feedback have similar effect on spatial memory task used in this study. However, types of feedback can change the performance of accuracy on transferring this skill among the blind.
Kvavilashvili, Lia; Ford, Ruth M
It is well documented that young children greatly overestimate their performance on tests of retrospective memory (RM), but the current investigation is the first to examine children's prediction accuracy for prospective memory (PM). Three studies were conducted, each testing a different group of 5-year-olds. In Study 1 (N=46), participants were asked to predict their success in a simple event-based PM task (remembering to convey a message to a toy mole if they encountered a particular picture during a picture-naming activity). Before naming the pictures, children listened to either a reminder story or a neutral story. Results showed that children were highly accurate in their PM predictions (78% accuracy) and that the reminder story appeared to benefit PM only in children who predicted they would remember the PM response. In Study 2 (N=80), children showed high PM prediction accuracy (69%) regardless of whether the cue was specific or general and despite typical overoptimism regarding their performance on a 10-item RM task using item-by-item prediction. Study 3 (N=35) showed that children were prone to overestimate RM even when asked about their ability to recall a single item-the mole's unusual name. In light of these findings, we consider possible reasons for children's impressive PM prediction accuracy, including the potential involvement of future thinking in performance predictions and PM. Copyright © 2014 Elsevier Inc. All rights reserved.
Li, Xin; Wang, Wenxiao; Wang, Ailin; Li, Peng; Zhang, Junying; Tao, Wuhai; Zhang, Zhanjun
Hypertension is related with cognitive decline in the elderly. The frontal-parietal executive system plays an important role in cognitive aging and is also vulnerable to damage in elderly patients with hypertension. Examination of the brain's functional characteristics in frontal-parietal regions of hypertension is likely to be important for understanding the neural mechanisms of hypertension's effect on cognitive aging. We address this issue by comparing hypertension and control-performers in a functional MRI study. Twenty-eight hypertensive patients and 32 elderly controls were tested with n-back task with two load levels. The hypertensive patients exhibited worse executive and memory abilities than control subjects. The patterns of brain activation changed under different working memory loads in the hypertensive patients, who exhibited reduced activation only in the precentral gyrus under low loads and reduced activation in the middle frontal gyrus, left medial superior frontal gyrus and right precuneus under high loads. Thus, more regions of diminished activation were observed in the frontal and parietal regions with increasing task difficulty. More importantly, we found that lower activation in changed frontal and parietal regions was associated with worse cognitive function in high loads. The results demonstrate the relationship between cognitive function and frontoparietal functional activation in hypertension and their relevance to cognitive aging risk. Our findings provide a better understanding of the mechanism of cognitive decline in hypertension and highlight the importance of brain protection in hypertension.
Hafiz, Md Abdullah Al
We experimentally demonstrate memory and logic devices based on an axially modulated clamped-guided arch resonator. The device are electrostatically actuated and capacitively sensed, while the resonance frequency modulation is achieved through an axial electrostatic force from the guided side of the clamped-guided arch microbeam. We present two case studies: first, a dynamic memory based on the nonlinear frequency response of the resonator, and second, a reprogrammable two-input logic gate based on the linear frequency modulation of the resonator. These devices show energy cost per memory/logic operation in pJ, are fully compatible with CMOS fabrication processes, have the potential for on-chip system integration, and operate at room temperature.
Gomarus, H Karin; Althaus, Monika; Wijers, Albertus A; Minderaa, Ruud B
Psychophysiological correlates of selective attention and working memory were investigated in a group of 18 healthy children using a visually presented selective memory search task. Subjects had to memorize one (load1) or 3 (load3) letters (memory set) and search for these among a recognition set consisting of 4 letters only if the letters appeared in the correct (relevant) color. Event-related potentials (ERPs) as well as alpha and theta event-related synchronization and desynchronization (ERD/ERS) were derived from the EEG that was recorded during the task. In the ERP to the memory set, a prolonged load-related positivity was found. In response to the recognition set, effects of relevance were manifested in an early frontal positivity and a later frontal negativity. Effects of load were found in a search-related negativity within the attended category and a suppression of the P3-amplitude. Theta ERS was most pronounced for the most difficult task condition during the recognition set, whereas alpha ERD showed a load-effect only during memorization. The manipulation of stimulus relevance and memory load affected both ERP components and ERD/ERS. The present paradigm may supply a useful method for studying processes of selective attention and working memory and can be used to examine group differences between healthy controls and children showing psychopathology.
Full Text Available The change detection task has become a standard method for estimating the storage capacity of visual working memory. Most researchers assume that this task isolates the properties of an active short-term storage system that can be dissociated from long-term memory systems. However, long-term memory storage may influence performance on this task. In particular, memory traces from previous trials may create proactive interference that sometimes leads to errors, thereby reducing estimated capacity. Consequently, the capacity of visual working memory may be higher than is usually thought, and correlations between capacity and other measures of cognition may reflect individual differences in proactive interference rather than individual differences in the capacity of the short-term storage system. Indeed, previous research has shown that change detection performance can be influenced by proactive interference under some conditions. The purpose of the present study was to determine whether the canonical version of the change detection task—in which the to-be-remembered information consists of simple, briefly presented features—is influenced by proactive interference. Two experiments were conducted using methods that ordinarily produce substantial evidence of proactive interference, but no proactive interference was observed. Thus, the canonical version of the change detection task can be used to assess visual working memory capacity with no meaningful influence of proactive interference.
Full Text Available Previous findings suggest that visual working memory preferentially remembers angry looking faces. However, the meaning of facial actions is construed in relation to context. To date, there are no studies investigating the role of perceiver-based context when processing emotional cues in visual working memory. To explore the influence of affective context on visual working memory for faces, we conducted two experiments using both a visual working memory task for emotionally expressive faces and a mood induction procedure. Affective context was manipulated by unpleasant (Experiment 1 and pleasant (Experiment 2 IAPS pictures in order to induce an affect high in motivational intensity (defensive or appetitive, respectively compared to a low arousal control condition. Results indicated specifically increased sensitivity of visual working memory for angry looking faces in the neutral condition. Enhanced visual working memory for angry faces was prevented by inducing affects of high motivational intensity. In both experiments, affective states led to a switch from specific enhancement of angry expressions in visual working memory to an equally sensitive representation of all emotional expressions. Our findings demonstrate that emotional expressions are of different behavioral relevance for the receiver depending on the affective context, supporting a functional organization of visual working memory along with flexible resource allocation. In visual working memory, stimulus processing adjusts to situational requirements and transitions from a specifically prioritizing default mode in predictable environments to a sensitive, hypervigilant mode in exposure to emotional events.
Drumond, Luciana Estefani; Mourão, Flávio Afonso Gonçalves; Leite, Hércules Ribeiro; Abreu, Renata Viana; Reis, Helton José; Moraes, Márcio Flávio Dutra; Pereira, Grace Schenatto; Massensini, André Ricardo
Physical activity has been proposed as a behavioral intervention that improves learning and memory; nevertheless, the mechanisms underlying these health benefits are still not well understood. Neuronal Calcium Sensor-1 (NCS-1) is a member of a superfamily of proteins that respond to local Ca(2+) changes shown to have an important role in learning and memory. The aim of the present study was to investigate the effects of swimming training on NCS-1 levels in the rat brain after accessing cognitive performance. Wistar rats were randomly assigned to sedentary (SG) or exercised groups (EG). The EG was subject to forced swimming activity, 30 min/day, 5 days/week, during 8 weeks. Progressive load trials were performed in the first and last week in order to access the efficiency of the training. After the 8 week training protocol, memory performance was evaluated by the novel object preference and object location tasks. NCS-1 levels were measured in the cortex and hippocampus using immunoblotting. The EG performed statistically better for the spatial short-term memory (0.73 ± 0.01) when compared to the SG (0.63 ± 0.02; P0.05). In addition, chronic exercise promoted a significant increase in hippocampal NCS-1 levels (1.8 ± 0.1) when compared to SG (1.17 ± 0.08; P0.05). Results suggest that physical exercise would modulate the state of the neural network regarding its potential for plastic changes: physical exercise could be modulating NCS-1 in an activity dependent manner, for specific neural substrates, thus enhancing the cellular/neuronal capability for plastic changes in these areas; which, in turn, would differentially effect ORM task performance for object recognition and displacement. Copyright © 2012 Elsevier Inc. All rights reserved.
Seno, Takeharu; Kawabe, Takahiro; Ito, Hiroyuki; Sunaga, Shoji
We examined whether illusory self-motion perception ("vection") induced by viewing upward and downward grating motion stimuli can alter the emotional valence of recollected autobiographical episodic memories. We found that participants recollected positive episodes more often while perceiving upward vection. However, when we tested a small moving…
Full Text Available In this work, we propose a Bayesian methodology to make inferences for the memory parameter and other characteristics under non-standard assumptions for a class of stochastic processes. This class generalizes the Gamma-modulated process, with trajectories that exhibit long memory behavior, as well as decreasing variability as time increases. Different values of the memory parameter influence the speed of this decrease, making this heteroscedastic model very flexible. Its properties are used to implement an approximate Bayesian computation and MCMC scheme to obtain posterior estimates. We test and validate our method through simulations and real data from the big earthquake that occurred in 2010 in Chile.
Hwang, Hyeon Jun; Yang, Jin Ho; Lee, Young Gon; Cho, Chunhum; Kang, Chang Goo; Kang, Soo Cheol; Park, Woojin; Lee, Byoung Hun
The feasibility of a high speed ferroelectric graphene memory device using a ferroelectric polymer (PVDF-TrFE)/graphene stack has been demonstrated. The conductivity of this metal-ferroelectric-graphene (MFG) device could be modulated up to 775% with a very fast programming speed down to 10 ns. Also, programmed states were maintained up to 1000 s with endurance over 1000 cycles. In addition to demonstrating a single memory device, the array-level integration and cell write/read functionality of a 4 × 4 MFG array adopting a graphene bit line has also been confirmed to show the feasibility of MFG memory.
Full Text Available In computational neuroscience it is generally accepted that human motor memory contains neural representations of the physics of the musculoskeletal system and the objects in the environment. These representations are called internal models. Force field studies, in which subjects have to adapt to dynamic perturbations induced by a robotic manipulandum, are an established tool to analyze the characteristics of such internal models. The aim of the current study was to investigate whether catch trials during force field learning could influence the consolidation of motor memory in more complex tasks. Thereby, the force field was more than double the force field of previous studies (35 Ns/m. Moreover, the arm of the subjects was not supported. A total of forty-six subjects participated in this study and performed center-out movements at a robotic manipulandum in two different force fields. Two control groups learned force field A on day 1 and were retested in the same force field on day 3 (AA. Two test groups additionally learned an interfering force field B (=-A on day 2 (ABA. The difference between the two test and control groups, respectively, was the absence (0% or presence (19% of catch trials, in which the force field was turned off suddenly. The results showed consolidation of force field A on day 3 for both control groups. Test groups showed no consolidation of force field A (19% catch trials and even poorer performance on day 3 (0% catch trials. In conclusion, it can be stated that catch trials seem to have a positive effect on the performance on day 3 but do not trigger a consolidation process as shown in previous studies that used a lower force field viscosity with supported arm. These findings indicate that the results of previous studies in which less complex tasks were analyzed, cannot be fully transferred to more complex tasks. Moreover, the effects of catch trials in these situations are insufficiently understood and further research
Park, Gyeong-Moon; Yoo, Yong-Ho; Kim, Deok-Hwa; Kim, Jong-Hwan
Robots are expected to perform smart services and to undertake various troublesome or difficult tasks in the place of humans. Since these human-scale tasks consist of a temporal sequence of events, robots need episodic memory to store and retrieve the sequences to perform the tasks autonomously in similar situations. As episodic memory, in this paper we propose a novel Deep adaptive resonance theory (ART) neural model and apply it to the task performance of the humanoid robot, Mybot, developed in the Robot Intelligence Technology Laboratory at KAIST. Deep ART has a deep structure to learn events, episodes, and even more like daily episodes. Moreover, it can retrieve the correct episode from partial input cues robustly. To demonstrate the effectiveness and applicability of the proposed Deep ART, experiments are conducted with the humanoid robot, Mybot, for performing the three tasks of arranging toys, making cereal, and disposing of garbage.
Li, Shijia; Weerda, Riklef; Milde, Christopher; Wolf, Oliver T; Thiel, Christiane M
Noradrenaline interacts with stress hormones in the amygdala and hippocampus to enhance emotional memory consolidation, but the noradrenergic-glucocorticoid interaction at retrieval, where stress impairs memory, is less understood. We used a genetic neuroimaging approach to investigate whether a genetic variation of the noradrenergic system impacts stress-induced neural activity in amygdala and hippocampus during recognition of emotional memory. This study is based on genotype-dependent reanalysis of data from our previous publication (Li et al. Brain Imaging Behav 2014). Twenty-two healthy male volunteers were genotyped for the ADRA2B gene encoding the α2B-adrenergic receptor. Ten deletion carriers and 12 noncarriers performed an emotional face recognition task, while their brain activity was measured with fMRI. During encoding, 50 fearful and 50 neutral faces were presented. One hour later, they underwent either an acute stress (Trier Social Stress Test) or a control procedure which was followed immediately by the retrieval session, where participants had to discriminate between 100 old and 50 new faces. A genotype-dependent modulation of neural activity at retrieval was found in the bilateral amygdala and right hippocampus. Deletion carriers showed decreased neural activity in the amygdala when recognizing emotional faces in control condition and increased amygdala activity under stress. Noncarriers showed no differences in emotional modulated amygdala activation under stress or control. Instead, stress-induced increases during recognition of emotional faces were present in the right hippocampus. The genotype-dependent effects of acute stress on neural activity in amygdala and hippocampus provide evidence for noradrenergic-glucocorticoid interaction in emotional memory retrieval.
Doland, G. D.
Shuttle Task 501 is an in-line task to test the performance and compatibility of radiofrequency links between the SSO and ground, and relay via a satellite. Under Shuttle Task 501 approach and landing test (ALT) phase only a limited portion of the communication and tracking (C&T) equipment is to be tested. The principal item to be tested is a frequency modulated (FM) data link. To test this RF link, an ALT FM System was designed, constructed, and the console wiring verified. A step-by-step procedure to be used to perform the ALT FM system is presented. The ALT FM system test is to be performed prior to delivery of the equipment to the Electronic Systems Test Laboratory (ESTL).
MBA has been working on the automated array assembly task of the Low-Cost Solar Array project. A baseline sequence for the manufacture of solar cell modules is specified. Starting with silicon wafers, the process goes through damage etching, texture etching, junction formation, plasma edge etch, aluminum back surface field formation, and screen printed metallization to produce finished solar cells which are then series connected on a ribbon and bonded into a finished glass, PVB, tedlar module. A number of steps required additional developmental effort to verify technical and economic feasibility. These steps include texture etching, plasma edge etch, aluminum back surface field formation, array layup and interconnect, and module edge sealing and framing.
Full Text Available The cerebellum plays a crucial role in motor learning and it acts as a predictive controller. Modeling it and embedding it into sensorimotor tasks allows us to create functional links between plasticity mechanisms, neural circuits and behavioral learning. Moreover, if applied to real-time control of a neurorobot, the cerebellar model has to deal with a real noisy and changing environment, thus showing its robustness and effectiveness in learning. A biologically inspired cerebellar model with distributed plasticity, both at cortical and nuclear sites, has been used. Two cerebellum-mediated paradigms have been designed: an associative Pavlovian task and a vestibulo-ocular reflex, with multiple sessions of acquisition and extinction and with different stimuli and perturbation patterns. The cerebellar controller succeeded to generate conditioned responses and finely tuned eye movement compensation, thus reproducing human-like behaviors. Through a productive plasticity transfer from cortical to nuclear sites, the distributed cerebellar controller showed in both tasks the capability to optimize learning on multiple time-scales, to store motor memory and to effectively adapt to dynamic ranges of stimuli.
Rummel, Jan; Einstein, Gilles O; Rampey, Hilary
Although forming implementation intentions (Gollwitzer, 1999) has been demonstrated to generally improve prospective memory, the underlying cognitive mechanisms are not completely understood. It has been proposed that implementation-intention encoding encourages spontaneous retrieval (McDaniel & Scullin, 2010). Alternatively one could assume the positive effect of implementation-intention encoding is caused by increased or more efficient monitoring for target cues. To test these alternative explanations and to further investigate the cognitive mechanisms underlying implementation-intention benefits, in two experiments participants formed the intention to respond to specific target cues in a lexical decision task with a special key, but then had to suspend this intention during an intervening word-categorisation task. Response times on trials directly following the occurrence of target cues in the intervening task were significantly slower with implementation-intention encoding than with standard encoding, indicating that spontaneous retrieval was increased (Experiment 1). However, when activation of the target cues was controlled for, similar slowing was found with both standard and implementation-intention encoding (Experiment 2). The results imply that implementation-intention encoding as well as increased target-cue activation foster spontaneous retrieval processes.
Erika K Hussey
Full Text Available We report the results of a bilingual continuous recognition memory task during which single- and multi-neuron activity was recorded in human subjects with intracranial microwire implants. Subjects (n = 5 were right-handed Spanish-English bilinguals who were undergoing evaluation prior to surgery for severe epilepsy. Subjects were presented with Spanish and English words and the task was to determine whether any given word had been seen earlier in the testing session, irrespective of the language in which it had appeared. Recordings in the left and right hippocampus revealed notable laterality, whereby both Spanish and English items that had been seen previously in the other language (switch trials triggered increased neural firing in the left hippocampus. Items that had been seen previously in the same language (repeat trials triggered increased neural firings in the right hippocampus. These results are consistent with theories that propose roles of both the left- and right-hemisphere in real-time linguistic processing. Importantly, this experiment presents the first instance of intracranial recordings in bilinguals performing a task with switching demands.
Gawda, Barbara; Szepietowska, Ewa
Trait anxiety is thought to be associated with pathological anxiety, and a risk factor for psychiatric disorders. The present study examines the brain mechanisms associated with trait anxiety during the performing of verbal fluency tasks. The aim is to show how trait anxiety modulates executive functions as measured by verbal fluency, and to explore the link between verbal fluency and anxiety due to the putative negative biases in high-anxious individuals. Seven tasks of verbal fluency were used: letter “k,” “f,” verbs, “animals,” “vehicles,” “joy,” and “fear.” The results of 35 subjects (whole sample), and 17 subjects (nine men, eight women) selected from the whole sample for the low/high-anxious groups on the basis of Trait Anxiety scores were analyzed. The subjects were healthy, Polish speaking, right-handed and aged from 20 to 35 years old. fMRI (whole-brain analysis with FWE corrections) was used to show the neural signals under active participation in verbal fluency tasks. The results confirm that trait anxiety slightly modulates neural activation during the performance of verbal fluency tasks, especially in the more difficult tasks. Significant differences were found in brain activation during the performance of more complex tasks between individuals with low anxiety and those with high anxiety. Greater activation in the right hemisphere, frontal gyri, and cerebellum was found in people with low anxiety. The results reflect better integration of cognitive and affective capacities in individuals with low anxiety. PMID:26903827
Guérard, Katherine; Saint-Aubin, Jean; Maltais, Marilyne; Lavoie, Hugo
During reading, a number of eye movements are made backward, on words that have already been read. Recent evidence suggests that such eye movements, called regressions, are guided by memory. Several studies point to the role of spatial memory, but evidence for the role of verbal memory is more limited. In the present study, we examined the factors that modulate the role of verbal memory in regressions. Participants were required to make regressions on target words located in sentences displayed on one or two lines. Verbal interference was shown to affect regressions, but only when participants executed a regression on a word located in the first part of the sentence, irrespective of the number of lines on which the sentence was displayed. Experiments 2 and 3 showed that the effect of verbal interference on words located in the first part of the sentence disappeared when participants initiated the regression from the middle of the sentence. Our results suggest that verbal memory is recruited to guide regressions, but only for words read a longer time ago.
Wang, Liping; Li, Xianchun; Hsiao, Steven S; Bodner, Mark; Lenz, Fred; Zhou, Yong-Di
Previous studies suggested that primary somatosensory (SI) neurons in well-trained monkeys participated in the haptic-haptic unimodal delayed matching-to-sample (DMS) task. In this study, 585 SI neurons were recorded in monkeys performing a task that was identical to that in the previous studies but without requiring discrimination and active memorization of specific features of a tactile or visual memorandum. A substantial number of those cells significantly changed their firing rate in the delay compared with the baseline, and some of them showed differential delay activity. These firing changes are similar to those recorded from monkeys engaged in active (working) memory. We conclude that the delay activity is not necessarily only observed as was generally thought in the situation of active memorization of different features between memoranda after those features have been actively discriminated. The delay activity observed in this study appears to be an intrinsic property of SI neurons and suggests that there exists a neural network in SI (the primary sensory cortex) for haptic working memory no matter whether the difference in features of memoranda needs to be memorized in the task or not. Over 400 SI neurons were also recorded in monkeys well-trained to discriminate two memoranda in the haptic-haptic DMS task for comparison of delay firing of SI neurons between the two different working memory tasks used in this study. The similarity observed in those two situations suggests that working memory uses already-existing memory apparatus by activating it temporarily. Our data also suggest that, through training (repetitive exposure to the stimulus), SI neurons may increase their involvement in the working memory of the memorandum.
Full Text Available Learning induced changes in protein acetylation, mediated by histone acetyl transferases (HATs, and the antagonistic histone deacetylases (HDACs play a critical role in memory formation. The status of histone acetylation affects the interaction between the transcription-complex and DNA and thus regulates transcription-dependent processes required for long-term memory (LTM. While the majority of studies report on the role of elevated acetylation in memory facilitation, we address the impact of both, increased and decreased acetylation on formation of appetitive olfactory memory in honeybees. We show that learning-induced changes in the acetylation of histone H3 at aminoacid-positions H3K9 and H3K18 exhibit distinct and different dynamics depending on the training strength. A strong training that induces LTM leads to an immediate increase in acetylation at H3K18 that stays elevated for hours. A weak training, not sufficient to trigger LTM, causes an initial increase in acetylation at H3K18, followed by a strong reduction in acetylation at H3K18 below the control group level. Acetylation at position H3K9 is not affected by associative conditioning, indicating specific learning-induced actions on the acetylation machinery. Elevating acetylation levels by blocking HDACs after conditioning leads to an improved memory. While memory after strong training is enhanced for at least 2 days, the enhancement after weak training is restricted to 1 day. Reducing acetylation levels by blocking HAT activity after strong training leads to a suppression of transcription-dependent LTM. The memory suppression is also observed in case of weak training, which does not require transcription processes. Thus, our findings demonstrate that acetylation-mediated processes act as bidirectional regulators of memory formation that facilitate or suppress memory independent of its transcription-requirement.
Blake, Mariano G; Boccia, Mariano M; Baratti, Carlos M
For several decades, one-trial inhibitory avoidance (IA) tasks have been used in the study of memory processing. In the present work, the effects of diazepam (DZP) (0.5mg/kg) and picrotoxin (PIC) (0.3mg/kg) on memory retrieval were assessed using two variants of a step-through IA situation in CF-1 mice. In the first variant, animals get into a dark compartment from an open illuminated platform (platform), whereas in the other, from an enclosed illuminated one (box). PIC impaired retention performance in the "platform-type" IA, but not in the "box-type". DZP enhanced retention performance in both types of IA task. These results evidence critical differences between the two step-through inhibitory avoidance tasks used, that might be relevant not only for retention performance during memory retrieval, but also for the theoretical interpretations and conclusions obtained from behavioral results.
blocked by concurrent infusion of low doses of the adrenergic agonist clenbuterol . Furthermore, low and otherwise ineffective doses of the adrenergic...we found that the retention-enhancing effects of clenbuterol were blocked by a low dose of the cholinergic antagonist atropine. In addition, a low dose...Involvement of the amygdala in the memory-enhancing effects of clenbuterol . Psychopharmacology, 1991, 104, 541-544. McGaugh, J.L. Neuromodulation and
Maxim S Kuschpel; Shuyan eLiu; Daniel J Schad; Stephan eHeinzel; Stephan eHeinzel; Stephan eHeinzel; Andreas eHeinz; Michael A Rapp
The interruption of learning processes by breaks filled with diverse activities is common in everyday life. We investigated the effects of active computer gaming and passive relaxation (rest and music) breaks on working memory performance. Young adults were exposed to breaks involving (i) eyes-open resting, (ii) listening to music and (iii) playing the video game Angry Birds before performing the n-back working memory task. Based on linear mixed-effects modeling, we found that playing the Ang...
Kuschpel, Maxim S.; Liu, Shuyan; Schad, Daniel J.; Heinzel, Stephan; Heinz, Andreas; Rapp, Michael A.
The interruption of learning processes by breaks filled with diverse activities is common in everyday life. We investigated the effects of active computer gaming and passive relaxation (rest and music) breaks on working memory performance. Young adults were exposed to breaks involving (i) eyes-open resting, (ii) listening to music and (iii) playing the video game “Angry Birds” before performing the n-back working memory task. Based on linear mixed-effects modeling, we found that playing the “...
García-Montes, José Manuel; Noguera, Carmen; Alvarez, Dolores; Ruiz, Marina; Cimadevilla Redondo, José Manuel
Schizotypy is a psychological construct related to schizophrenia. The exact relationship between both entities is not clear. In recent years, schizophrenia has been associated with hippocampal abnormalities and spatial memory problems. The aim of this study was to determine possible links between high schizotypy (HS) and low schizotypy (LS) and spatial abilities, using virtual reality tasks. We hypothesised that the HS group would exhibit a lower performance in spatial memory tasks than the LS group. Two groups of female students were formed according to their score on the ESQUIZO-Q-A questionnaire. HS and LS subjects were tested on two different tasks: the Boxes Room task, a spatial memory task sensitive to hippocampal alterations and a spatial recognition task. Data showed that both groups mastered both tasks. Groups differed in personality features but not in spatial performance. These results provide valuable information about the schizotypy-schizophrenia connections. Schizotypal subjects are not impaired on spatial cognition and, accordingly, the schizotypy-schizophrenia relationship is not straightforward.
Marlieke T R van Kesteren
Full Text Available Newly learned information that is congruent with a preexisting schema is often better remembered than information that is incongruent. This schema effect on memory has previously been associated to more efficient encoding and consolidation mechanisms. However, this effect is not always consistently supported in the literature, with differential schema effects reported for different types of memory, different retrieval cues, and the possibility of time-dependent effects related to consolidation processes. To examine these effects more directly, we tested participants on two different types of memory (item recognition and associative memory for newly encoded visuo-tactile associations at different study-test intervals, thus probing memory retrieval accuracy for schema-congruent and schema-incongruent items and associations at different time points (t = 0, t = 20, and t = 48 hours after encoding. Results show that the schema effect on visual item recognition only arises after consolidation, while the schema effect on associative memory is already apparent immediately after encoding, persisting, but getting smaller over time. These findings give further insight into different factors influencing the schema effect on memory, and can inform future schema experiments by illustrating the value of considering effects of memory type and consolidation on schema-modulated retrieval.
Guevara, Miguel Angel; Cruz Paniagua, Edwin Iván; Hernández González, Marisela; Sandoval Carrillo, Ivett Karina; Almanza Sepúlveda, Mayra Linné; Hevia Orozco, Jorge Carlos; Amezcua Gutiérrez, Claudia
Short-term memory and working memory are two closely-related concepts that involve the prefrontal and parietal areas. These two types of memory have been evaluated by means of the spatial span task in its forward and backward conditions, respectively. To determine possible neurofunctional differences between them, this study recorded electroencephalographic activity (EEG) in the frontopolar (Fp1, Fp2), dorsolateral (F3, F4), and parietal (P3 and P4) areas during performance of the forward and backward conditions of this task in young men. The backward condition (an indicator of working memory) was characterized by fewer correct answers, higher absolute power (AP) of the delta band in dorsolateral areas, and a lower correlation between frontopolar and dorsolateral regions in the fast bands (alpha, beta and gamma), mainly in the right hemisphere. The prefrontal EEG changes during backward performance may be associated with the higher attentional demands and inhibition processes required to invert the order of reproduction of a sequence. These data provide evidence that the forward and backward conditions of the spatial span task can be distinguished on the basis of neurofunctional activity and performance, and that each one is associated with a distinct pattern of electrical activity and synchronization between prefrontal areas. The higher AP of the delta band and lower correlation of the fast bands, particularly between right prefrontal areas during the backward condition of this visuospatial task, suggest greater participation by the right prefrontal areas in working memory. Copyright © 2018 Elsevier B.V. All rights reserved.
Barzykowski, Krystian; Niedźwieńska, Agnieszka
Recent studies on involuntary autobiographical memories (IAMs) in daily life have shown that they are most frequently reported during daily routines (e.g. while ironing). Such studies have suggested that reporting IAMs may be influenced by the level of the ongoing task demands and availability of cognitive resources. In two studies, we investigated the effects of cognitive load on reporting IAMs. To examine the presumed cognitive load dependency of IAMs, we utilised an often-employed experimental paradigm (Schlagman & Kvavilashvili, 2008) to elicit IAMs under conditions that differed in cognitive load. When performing a vigilance task, participants had to interrupt the task each time they experienced any spontaneous mental contents and write them down. We manipulated the level of cognitive load by either instructing (cognitive load group) or not instructing (control group) participants to perform an additional demanding task. We compared the groups on the number of IAMs and other mental contents (non-IAM contents) recorded, as well as on the frequency of IAMs that was calculated as a proportion of IAMs in all mental contents reported by the participant. We expected that if reporting IAMs depends on the level of cognitive demands, then we should observe lower frequency of IAMs in the cognitive load group compared to the control group. Consistently across studies, we observed a lower number of IAMs and non-IAM contents in the cognitive load group. However, IAMs unexpectedly constituted a higher percentage of all mental contents when participants were cognitively loaded. Further implications of the cognitive load effects for IAMs research and experimental methodology are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.
We investigated the relative discriminatory efficacy of an event-based prospective memory (PM) task, in which specificity of the instructions and perceptual salience of the PM cue were manipulated, compared with two widely used retrospective memory (RM) tests (Rivermead Paragraph Recall Test and CERAD-Word List Test), when detecting mild cognitive impairment of suspected Alzheimer\\'s disease etiology (MCI-AD) (N = 19) from normal controls (NC) (N = 21). Statistical analyses showed high discriminatory capacity of the PM task for detecting MCI-AD. The Non-Specific-Non-Salient condition proved particularly useful in detecting MCI-AD, possibly reflecting the difficulty of the task, requiring more strategic attentional resources to monitor for the PM cue. With a cutoff score of <4\\/10, the Non-Specific-Non-Salient condition achieved a sensitivity = 84%, and a specificity = 95%, superior to the most discriminative RM test used (CERAD-Total Learning: sensitivity = 83%; specificity = 76%). Results suggest that PM is an early sign of memory failure in MCI-AD and may be a more pronounced deficit than retrospective failure, probably reflecting the greater self-initiated retrieval demands involved in the PM task used. Limitations include the relatively small sample size, and the use of a convenience sample (i.e. memory clinic attenders and healthy active volunteers), reducing the generalizability of the results, which should be regarded as preliminary. (JINS, 2009, 15, 154-159.).
Millman, Rebecca E.; Mattys, Sven L.
Purpose: Background noise can interfere with our ability to understand speech. Working memory capacity (WMC) has been shown to contribute to the perception of speech in modulated noise maskers. WMC has been assessed with a variety of auditory and visual tests, often pertaining to different components of working memory. This study assessed the relationship between speech perception in modulated maskers and components of auditory verbal working memory (AVWM) over a range of signal-to-noise rati...
Krasny-Pacini, Agata; Servant, Violette; Alzieu, Christine; Chevignard, Mathilde
International audience; Prospective memory (PM) has been shown to be impaired in children with acquired brain injuries (ABI) and is a major concern for parents. Few studies have addressed this issue and most used tasks that are not ecologically valid. The aims of this study were (1) to explore if children who have sustained an ABI suffer PM impairment, measured both by the Children’s Cooking task (CCT) PM score and using the 2 PM subtests of the Rivermead Behavioral Memory Test (RBMT), and (2...
Baluchnejadmojarad, Tourandokht; Roghani, Mehrdad
Due to anti-diabetic and antioxidant activity of green tea epigallocatechin gallate (EGCG) and the existence of evidence for its beneficial effect on cognition and memory, this research study was conducted to evaluate, for the first time, the efficacy of chronic EGCG on alleviation of learning and memory deficits in streptozotocin (STZ)-diabetic rats. Male Wistar rats were divided into control, diabetic, EGCG-treated-control and -diabetic groups. EGCG was administered at a dose of 20 and 40 mg/kg/day for 7 weeks. Learning and memory was evaluated using Y maze, passive avoidance, and radial 8-arm maze (RAM) tests. Oxidative stress markers and involvement of nitric oxide system were also evaluated. Alternation score of the diabetic rats in Y maze was lower than that of control and a significant impairment was observed in retention and recall in passive avoidance test (pRAM task and EGCG (40 mg/kg) significantly ameliorated these changes (pmemory respectively. Meanwhile, increased levels of malondialdehyde (MDA) and nitrite in diabetic rats significantly reduced due to EGCG treatment (pmemory deficits in STZ-diabetic rats through attenuation of oxidative stress and modulation of NO. Copyright © 2011 Elsevier B.V. All rights reserved.
Shen, Jiahui; Zhang, Gaoyan; Zhu, Chaozhe; Yao, Li; Zhao, Xiaojie
Neuroimaging studies of working memory training have identified the alteration of brain activity as well as the regional interactions within the functional networks such as central executive network (CEN) and default mode network (DMN). However, how the interaction within and between these multiple networks is modulated by the training remains unclear. In this paper, we examined the interaction of three training-induced brain networks during working memory training based on real-time functional magnetic resonance imaging (rtfMRI). Thirty subjects assigned to the experimental and control group respectively participated in two times training separated by seven days. Three networks including silence network (SN), CEN and DMN were identified by the training data with the calculated function connections within each network. Structural equation modeling (SEM) approach was used to construct the directional connectivity patterns. The results showed that the causal influences from the percent signal changes of target ROI to the SN were positively changed in both two groups, as well as the causal influence from the SN to CEN was positively changed in experimental group but negatively changed in control group from the SN to DMN. Further correlation analysis of the changes in each network with the behavioral improvements showed that the changes in SN were stronger positively correlated with the behavioral improvement of letter memory task. These findings indicated that the SN was not only a switch between the target ROI and the other networks in the feedback training but also an essential factor to the behavioral improvement.
Vossen, Alexandra Y; Ross, Veerle; Jongen, Ellen M M; Ruiter, Robert A C; Smulders, Fren T Y
Visuospatial attentional orienting has typically been studied in abstract tasks with low ecological validity. However, real-life tasks such as driving require allocation of working memory (WM) resources to several subtasks over and above orienting in a complex sensory environment. The aims of this study were twofold: firstly, to establish whether electrophysiological signatures of attentional orienting commonly observed under simplified task conditions generalize to a more naturalistic task situation with realistic-looking stimuli, and, secondly, to assess how these signatures are affected by increased WM load under such conditions. Sixteen healthy participants performed a dual task consisting of a spatial cueing paradigm and a concurrent verbal memory task that simulated aspects of an actual traffic situation. Behaviorally, we observed a load-induced detriment of sensitivity to targets. In the EEG, we replicated orienting-related alpha lateralization, the lateralized ERPs ADAN, EDAN, and LDAP, and the P1-N1 attention effect. When WM load was high (i.e., WM resources were reduced), lateralization of oscillatory activity in the lower alpha band was delayed. In the ERPs, we found that ADAN was also delayed, while EDAN was absent. Later ERP correlates were unaffected by load. Our results show that the findings in highly controlled artificial tasks can be generalized to spatial orienting in ecologically more valid tasks, and further suggest that the initiation of spatial orienting is delayed when WM demands of an unrelated secondary task are high. © 2015 Society for Psychophysiological Research.
Tunur, Tumay; Stelly, Claire E.; Schrader, Laura Ann
Downstream regulatory element antagonist modulator (DREAM)/calsenilin(C)/K+ channel interacting protein 3 (KChIP3) is a multifunctional Ca[superscript 2+]-binding protein highly expressed in the hippocampus that inhibits hippocampus-sensitive memory and synaptic plasticity in male mice. Initial studies in our lab suggested opposing effects of…
Rendeiro, Catarina; Guerreiro, João D T; Williams, Claire M; Spencer, Jeremy P E
There is considerable interest in the potential of a group of dietary-derived phytochemicals known as flavonoids in modulating neuronal function and thereby influencing memory, learning and cognitive function. The present review begins by detailing the molecular events that underlie the acquisition and consolidation of new memories in the brain in order to provide a critical background to understanding the impact of flavonoid-rich diets or pure flavonoids on memory. Data suggests that despite limited brain bioavailability, dietary supplementation with flavonoid-rich foods, such as blueberry, green tea and Ginkgo biloba lead to significant reversals of age-related deficits on spatial memory and learning. Furthermore, animal and cellular studies suggest that the mechanisms underpinning their ability to induce improvements in memory are linked to the potential of absorbed flavonoids and their metabolites to interact with and modulate critical signalling pathways, transcription factors and gene and/or protein expression which control memory and learning processes in the hippocampus; the brain structure where spatial learning occurs. Overall, current evidence suggests that human translation of these animal investigations are warranted, as are further studies, to better understand the precise cause-and-effect relationship between flavonoid intake and cognitive outputs.
hayder M. al-kuraishy
Full Text Available Abstract Aim: The present study investigates the effect of combined treatment with Ginkgo biloba and/or rhodiola rosea on psychomotor vigilance task and short-term working memory accuracy. Subjects and Methods: A total number of 112 volunteers was enrolled to study the effect of Ginkgo biloba and rhodiola rosea on psychomotor vigilance task and short-term working memory accuracy as compared to placebo effects,the central cognitive effect was assessed by Critical flicker-fusion frequency (CFFF, Psychomotor vigilance Task (PVT and computerized N-back test. Results: Placebo produced no significant effects on all neurocognitive tests measure p>0.05 in normal healthy volunteers, Ginkgo biloba or Rhodiola rosea improve psychomotor vigilance task and low to moderate working memory accuracy, The combined effect of Rhodiola rosea and Ginkgo biloba leading to more significant effect on psychomotor vigilance task, all levels of short term working memory accuracy and critical fusion versus flicker p<0.01, more than of Ginkgo biloba or Rhodiola rosea when they used alone. Conclusion: The combined effect of Rhodiola rosea and Ginkgo biloba leading to more significant effect on cognitive function than either Ginkgo biloba or Rhodiola rosea when they used alone. [J Intercult Ethnopharmacol 2016; 5(1.000: 7-13
hayder M. al-kuraishy
Full Text Available Abstract Aim: The present study investigates the effect of combined treatment with Ginkgo biloba and/or rhodiola rosea on psychomotor vigilance task and short-term working memory accuracy. Subjects and Methods: A total number of 112 volunteers was enrolled to study the effect of Ginkgo biloba and rhodiola rosea on psychomotor vigilance task and short-term working memory accuracy as compared to placebo effects,the central cognitive effect was assessed by Critical flicker-fusion frequency (CFFF, Psychomotor vigilance Task (PVT and computerized N-back test. Results: Placebo produced no significant effects on all neurocognitive tests measure p>0.05 in normal healthy volunteers, Ginkgo biloba or Rhodiola rosea improve psychomotor vigilance task and low to moderate working memory accuracy, The combined effect of Rhodiola rosea and Ginkgo biloba leading to more significant effect on psychomotor vigilance task, all levels of short term working memory accuracy and critical fusion versus flicker p [J Complement Med Res 2016; 5(1.000: 7-13
Wirz, Lisa; Wacker, Jan; Felten, Andrea; Reuter, Martin; Schwabe, Lars
Stress induces a shift from hippocampus-based "cognitive" toward dorsal striatum-based "habitual" learning and memory. This shift is thought to have important implications for stress-related psychopathologies, including post-traumatic stress disorder (PTSD). However, there is large individual variability in the stress-induced bias toward habit memory, and the factors underlying this variability are completely unknown. Here we hypothesized that a functional deletion variant of the gene encoding the α2b-adrenoceptor ( ADRA2B ), which has been linked to emotional memory processes and increased PTSD risk, modulates the stress-induced shift from cognitive toward habit memory. In two independent experimental studies, healthy humans were genotyped for the ADRA2B deletion variant. After a stress or control manipulation, participants completed a dual-solution learning task while electroencephalographic (Study I) or fMRI measurements (Study II) were taken. Carriers compared with noncarriers of the ADRA2B deletion variant exhibited a significantly reduced bias toward habit memory after stress. fMRI results indicated that, whereas noncarriers of the ADRA2B deletion variant showed increased functional connectivity between amygdala and putamen after stress, this increase in connectivity was absent in carriers of the deletion variant, who instead showed overall enhanced connectivity between amygdala and entorhinal cortex. Our results indicate that a common genetic variation of the noradrenergic system modulates the impact of stress on the balance between cognitive and habitual memory systems, most likely via altered amygdala orchestration of these systems. SIGNIFICANCE STATEMENT Stressful events have a powerful effect on human learning and memory. Specifically, accumulating evidence suggests that stress favors more rigid dorsal striatum-dependent habit memory, at the expense of flexible hippocampus-dependent cognitive memory. Although this shift may have important implications
Rubin, Leah H; Wu, Minjie; Sundermann, Erin E; Meyer, Vanessa J; Smith, Rachael; Weber, Kathleen M; Cohen, Mardge H; Little, Deborah M; Maki, Pauline M
HIV-infected women may be particularly vulnerable to verbal learning and memory deficits. One factor contributing to these deficits is high perceived stress, which is associated with prefrontal cortical (PFC) atrophy and memory outcomes sensitive to PFC function, including retrieval and semantic clustering. We examined the association between stress and PFC activation during a verbal memory task in 36 HIV-infected women from the Chicago Consortium of the Women's Interagency HIV Study (WIHS) to better understand the role of the PFC in this stress-related impairment. Participants completed standardized measures of verbal learning and memory and stress (perceived stress scale-10). We used functional magnetic resonance imaging to assess brain function while participants completed encoding and recognition phases of a verbal memory task. HIV-infected women with higher stress (scores in top tertile) performed worse on all verbal memory outcomes including strategic encoding (p stress (scores in lower two tertiles). Patterns of brain activation during recognition (but not encoding) differed between women with higher vs. lower stress. During recognition, women with higher stress demonstrated greater deactivation in medial PFC and posterior cingulate cortex compared to women with lower stress (p stress might alter the function of the medial PFC in HIV-infected women resulting in less efficient strategic retrieval and deficits in verbal memory.
Sanguinetti, Joseph L; Peterson, Mary A
Traditional theories of vision assume that object segregation occurs before access to object memories. Yet, behavioral evidence shows that familiar configuration is a prior for segregation, and electrophysiological experiments demonstrate these memories are accessed rapidly. A behavioral index of the speed of access is lacking, however. Here we asked how quickly behavior is influenced by object memories that are accessed in the course of object segregation. We investigated whether access to object memories on the groundside of a border can slow behavior during a rapid categorization task. Participants viewed two silhouettes that depicted a real-world and a novel object. Their task was to saccade toward the real-world object as quickly as possible. Half of the nontarget novel objects were ambiguous in that a portion of a real-world object was suggested, but not consciously perceived, on the groundside of their borders. The rest of the nontargets were unambiguous. We tested whether saccadic reaction times were perturbed by the real-world objects suggested on the groundside of ambiguous novel silhouettes. In Experiments 1 and 2, saccadic reaction times were slowed when nontargets were ambiguous rather than unambiguous. Experiment 2 set an upper limit of 190 ms on the time required for object memories in grounds to influence behavior. Experiment 3 ruled out factors that could have produced longer latencies other than access to object memories. These results provide the first behavioral index of how quickly memories of objects suggested in grounds can influence behavior, placing the upper limit at 190 ms.
Otsuka, Yuki; Osaka, Naoyuki
This study investigated the effects of three working memory components-the central executive, phonological loop, and visuospatial sketchpad-on performance differences in complex mental arithmetic between individuals. Using the dual-task method, we examined how performance during two-digit addition was affected by load on the central executive (random tapping condition), phonological loop (articulatory suppression condition), and visuospatial sketchpad (spatial tapping condition) compared to that under no load (control condition) in high- and low-performers of complex mental arithmetic in Experiment 1. Low-performers showed an increase in errors under the random tapping and articulatory suppression conditions, whereas high-performers showed an increase of errors only under the random tapping condition. In Experiment 2, we conducted similar experiments on only the high-performers but used a shorter presentation time of each number. We found the same pattern for performing complex mental arithmetic as seen in Experiment 1. These results indicate that high-performers might reduce their dependence on the phonological loop, because the central executive enables them to choose a strategy in which they use less working memory capacity.
Andrew J. Heinz
Full Text Available Studies exploring the role of neural oscillations in cognition have revealed sustained increases in alpha-band power (ABP during the delay period of verbal and visual working memory (VWM tasks. There have been various proposals regarding the functional significance of such increases, including the inhibition of task-irrelevant cortical areas as well as the active retention of information in VWM. The present study examines the role of delay-period ABP in mediating the effects of interference arising from on-going visual processing during a concurrent VWM task. Specifically, we reasoned that, if set-size dependent increases in ABP represent the gating out of on-going task-irrelevant visual inputs, they should be predictive with respect to some modulation in visual evoked potentials resulting from a task-irrelevant delay period probe stimulus. In order to investigate this possibility, we recorded the electroencephalogram while subjects performed a change detection task requiring the retention of two or four novel shapes. On a portion of trials, a novel, task-irrelevant bilateral checkerboard probe was presented mid-way through the delay. Analyses focused on examining correlations between set-size dependent increases in ABP and changes in the magnitude of the P1, N1 and P3a components of the probe-evoked response and how such increases might be related to behavior. Results revealed that increased delay-period ABP was associated with changes in the amplitude of the N1 and P3a event-related potential (ERP components, and with load-dependent changes in capacity when the probe was presented during the delay. We conclude that load-dependent increases in ABP likely play a role in supporting short-term retention by gating task-irrelevant sensory inputs and suppressing potential sources of disruptive interference.
Joshua Benjamin Ewen
Full Text Available Autism spectrum disorders (ASD are thought to result in part from altered cortical excitatory-inhibitory balance; this pathophysiology may impact the generation of oscillations on EEG. We investigated premotor-parietal cortical physiology associated with praxis, which has strong theoretical and empirical associations with ASD symptomatology. 25 children with high-functioning ASD (HFA and 33 controls performed a praxis task involving the pantomiming of tool use, while EEG was recorded. We assessed task-related modulation of signal power in alpha and beta frequency bands. Compared with controls, subjects with HFA showed 27% less left central (motor/premotor beta (18-22 Hz event-related desynchronization (ERD (p = 0.030, as well as 24% less left parietal alpha (7-13 Hz ERD (p = 0.046. Within the HFA group, blunting of central ERD attenuation was associated with impairments in clinical measures of praxis imitation (r = -0.4; p = 0.04 and increased autism severity (r = 0.48; p = 0.016. The modulation of central beta activity is associated, among other things, with motor imagery, which may be necessary for imitation. Impaired imitation has been associated with core features of ASD. Altered modulation of oscillatory activity may be mechanistically involved in those aspects of motor network function that relate to the core symptoms of ASD.
Ortega, Rodrigo; López, Vladimir; Aboitiz, Francisco
The present study explores the neural correlates of voluntary modulations of attention in an auditory-visual matching task. Visual stimuli (a female or a male face) were preceded in close temporal proximity by auditory stimuli consisting of the Spanish word for "man" and "woman" ("hombre" or "mujer"). In 80% of the trials the gender of the two stimuli coincided. Participants were asked to mentally count the specific instances in which a female face appeared after hearing the word "man" (10 % of the trials). Our results show attention-related amplitude modulation of the early visual ERP components NI and anterior P2, but also amplitude modulations of (i) the N270 potential usually associated with conflict detection, (ii) a P300 wave related to infrequency, and (iii) an N400 potential related to semantic incongruence. The elicitation of these latter components varied according to task manipulations, evidencing the role of voluntary allocation of attention in fine-tuning cognitive processing, which includes basic processes like detection of infrequency or semantic incongruity often considered to be volition-independent.
Full Text Available Working memory has been described as an interface between cognition and action, or a system for access to a limited amount of information needed in complex cognition. Access to morphological information is needed for comprehending and producing sentences. The present study probed working memory for morphologically complex word forms in Finnish, a morphologically rich language. We studied monomorphemic (boy, inflected (boy+’s and derived (boy+hood words in three tasks. Simple span, immediate serial recall of words, in Experiment 1, is assumed to mainly rely on information in the focus of attention. Sentence span, a dual task combining sentence reading with recall of the last word (Experiment 2 or of a word not included in the sentence (Experiment 3 is assumed to involve establishment of a search set in long-term memory for fast activation into the focus of attention. Recall was best for monomorphemic and worst for inflected word forms with performance on derived words in between. However, there was an interaction between word type and experiment, suggesting that complex span is more sensitive to morphological complexity in derivations than simple span. This was explored in a within-subjects Experiment 4 combining all three tasks. An interaction between morphological complexity and task was replicated. Both inflected and derived forms increased load in working memory. In simple span, recall of inflectional forms resulted in form errors. Complex span tasks were more sensitive to morphological load in derived words, possibly resulting from interference from morphological neighbors in the mental lexicon. The results are best understood as involving competition among inflectional forms when binding words from input into an output structure, and competition from morphological neighbors in secondary memory during cumulative retrieval-encoding cycles. Models of verbal recall need to be able to represent morphological as well as phonological and
González-Garrido, Andrés A.; Gudayol-Ferré, Esteban; Guàrdia-Olmos, Joan
In recent years, increasing attention has been paid to the effects of Type 1 Diabetes (T1D) on cognitive functions. T1D onset usually occurs during childhood, so it is possible that the brain could be affected during neurodevelopment. We selected young patients of normal intelligence with T1D onset during neurodevelopment, no complications from diabetes, and adequate glycemic control. The purpose of this study was to compare the neural BOLD activation pattern in a group of patients with T1D versus healthy control subjects while performing a visuospatial working memory task. Sixteen patients and 16 matched healthy control subjects participated. There was no significant statistical difference in behavioral performance between the groups, but, in accordance with our hypothesis, results showed distinct brain activation patterns. Control subjects presented the expected activations related to the task, whereas the patients had greater activation in the prefrontal inferior cortex, basal ganglia, posterior cerebellum, and substantia nigra. These different patterns could be due to compensation mechanisms that allow them to maintain a behavioral performance similar to that of control subjects. PMID:26266268
Geisa B. Gallardo-Moreno
Full Text Available In recent years, increasing attention has been paid to the effects of Type 1 Diabetes (T1D on cognitive functions. T1D onset usually occurs during childhood, so it is possible that the brain could be affected during neurodevelopment. We selected young patients of normal intelligence with T1D onset during neurodevelopment, no complications from diabetes, and adequate glycemic control. The purpose of this study was to compare the neural BOLD activation pattern in a group of patients with T1D versus healthy control subjects while performing a visuospatial working memory task. Sixteen patients and 16 matched healthy control subjects participated. There was no significant statistical difference in behavioral performance between the groups, but, in accordance with our hypothesis, results showed distinct brain activation patterns. Control subjects presented the expected activations related to the task, whereas the patients had greater activation in the prefrontal inferior cortex, basal ganglia, posterior cerebellum, and substantia nigra. These different patterns could be due to compensation mechanisms that allow them to maintain a behavioral performance similar to that of control subjects.
Dumontheil, Iroise; Klingberg, Torkel
Visuospatial working memory (WM) capacity is highly correlated with mathematical reasoning abilities and can predict future development of arithmetical performance. Activity in the intraparietal sulcus (IPS) during visuospatial WM tasks correlates with interindividual differences in WM capacity. This region has also been implicated in numerical representation, and its structure and activity reflect arithmetical performance impairments (e.g., dyscalculia). We collected behavioral (N = 246) and neuroimaging data (N = 46) in a longitudinal sample to test whether IPS activity during a visuospatial WM task could provide more information than psychological testing alone and predict arithmetical performance 2 years later in healthy participants aged 6-16 years. Nonverbal reasoning and verbal and visuospatial WM measures were found to be independent predictors of arithmetical outcome. In addition, WM activation in the left IPS predicted arithmetical outcome independently of behavioral measures. A logistic model including both behavioral and imaging data showed improved sensitivity by correctly classifying more than twice as many children as poor arithmetical performers after 2 years than a model with behavioral measures only. These results demonstrate that neuroimaging data can provide useful information in addition to behavioral assessments and be used to improve the identification of individuals at risk of future low academic performance.
Harrison, F.E.; Hosseini, A.H.; McDonald, M.P.
The effects of abnormally high or low stress on learning are well established. The Barnes maze and Morris water maze are two commonly-used tests of spatial memory, of which the water maze is considered more stressful; however, until now this has not been demonstrated empirically. In the present study, mice matched for performance on commonly-used anxiety tasks were trained on either the Barnes maze or water maze or received no cognitive testing. Water-maze training induced greater increases in plasma corticosterone than did Barnes maze training, assessed 30 min. after the final session. Importantly, spatial learning was inversely correlated with corticosterone levels in the water maze but not the Barnes maze, suggesting that performance on the water maze may be more affected by test-induced stress even within wild-type subjects of the same age and gender. These findings are important when considering the appropriate cognitive tasks for any experiment in which stress responses may differ systematically across groups. PMID:18996418
Miskowiak, K W; Kjaerstad, H L; Støttrup, M M; Svendsen, A M; Demant, K M; Hoeffding, L K; Werge, T M; Burdick, K E; Domschke, K; Carvalho, A F; Vieta, E; Vinberg, M; Kessing, L V; Siebner, H R; Macoveanu, J
Cognitive dysfunction affects a substantial proportion of patients with bipolar disorder (BD), and genetic-imaging paradigms may aid in the elucidation of mechanisms implicated in this symptomatic domain. The Val allele of the functional Val158Met polymorphism of the catechol-O-methyltransferase (COMT) gene is associated with reduced prefrontal cortex dopamine and exaggerated working memory-related prefrontal activity. This functional magnetic resonance imaging (fMRI) study investigated for the first time whether the COMT Val158Met genotype modulates prefrontal activity during spatial working memory in BD. Sixty-four outpatients with BD in full or partial remission were stratified according to COMT Val158Met genotype (ValVal [n=13], ValMet [n=34], and MetMet [n=17]). The patients completed a spatial n-back working memory task during fMRI and the Cambridge Neuropsychological Test Automated Battery (CANTAB) Spatial Working Memory test outside the scanner. During high working memory load (2-back vs 1-back), Val homozygotes displayed decreased activity relative to ValMet individuals, with Met homozygotes displaying intermediate levels of activity in the right dorsolateral prefrontal cortex (dlPFC) (P=.016). Exploratory whole-brain analysis revealed a bilateral decrease in working memory-related dlPFC activity in the ValVal group vs the ValMet group which was not associated with differences in working memory performance during fMRI. Outside the MRI scanner, Val carriers performed worse in the CANTAB Spatial Working Memory task than Met homozygotes (P≤.006), with deficits being most pronounced in Val homozygotes. The association between Val allelic load, dlPFC activity and WM impairment points to a putative role of aberrant PFC dopamine tonus in the cognitive impairments in BD. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Saive, Anne-Lise; Royet, Jean-Pierre; Ravel, Nadine; Thévenet, Marc; Garcia, Samuel; Plailly, Jane
We behaviorally explore the link between olfaction, emotion and memory by testing the hypothesis that the emotion carried by odors facilitates the memory of specific unique events. To investigate this idea, we used a novel behavioral approach inspired by a paradigm developed by our team to study episodic memory in a controlled and as ecological as possible way in humans. The participants freely explored three unique and rich laboratory episodes; each episode consisted of three unfamiliar odors (What) positioned at three specific locations (Where) within a visual context (Which context). During the retrieval test, which occurred 24–72 h after the encoding, odors were used to trigger the retrieval of the complex episodes. The participants were proficient in recognizing the target odors among distractors and retrieving the visuospatial context in which they were encountered. The episodic nature of the task generated high and stable memory performances, which were accompanied by faster responses and slower and deeper breathing. Successful odor recognition and episodic memory were not related to differences in odor investigation at encoding. However, memory performances were influenced by the emotional content of the odors, regardless of odor valence, with both pleasant and unpleasant odors generating higher recognition and episodic retrieval than neutral odors. Finally, the present study also suggested that when the binding between the odors and the spatio-contextual features of the episode was successful, the odor recognition and the episodic retrieval collapsed into a unique memory process that began as soon as the participants smelled the odors. PMID:24936176
Full Text Available We behaviorally explore the link between olfaction, emotion and memory by testing the hypothesis that the emotion carried by odors facilitates the memory of specific unique events. To investigate this idea, we used a novel behavioral approach inspired by a paradigm developed by our team to study episodic memory in a controlled and as ecological as possible way in humans. The participants freely explored three unique and rich laboratory episodes; each episode consisted of three unfamiliar odors (What positioned at three specific locations (Where within a visual context (Which context. During the retrieval test, which occurred 24 to 72 hours after the encoding, odors were used to trigger the retrieval of the complex episodes. The participants were proficient in recognizing the target odors among distractors and retrieving the visuospatial context in which they were encountered. The episodic nature of the task generated high and stable memory performances, which were accompanied by faster responses and slower and deeper breathing. Successful odor recognition and episodic memory were not related to differences in odor investigation at encoding. However, memory performances were influenced by the emotional content of the odors, regardless of odor valence, with both pleasant and unpleasant odors generating higher recognition and episodic retrieval than neutral odors. Finally, the present study also suggested that when the binding between the odors and the spatio-contextual features of the episode was successful, the odor recognition and the episodic retrieval collapsed into a unique memory process that began as soon as the participants smelled the odors.
Vanessa C Rossi
Full Text Available Numerous studies show that sleep deprivation (SD impacts negatively on cognitive processes, including learning and memory. Memory formation encompasses distinct phases of which acquisition, consolidation and retrieval are better known. Previous studies with pre-training SD induced by the platform method have shown impairment in fear conditioning tasks. Nonetheless, pre-training manipulations do not allow the distinction between effects on acquisition and/or consolidation, interfering, ultimately, on recall of/performance in the task. In the present study, animals were first trained in contextual and tone fear conditioning tasks and then submitted to SD with the purpose to evaluate the effect of this manipulation on different stages of the learning process, e.g. in the uptake of (new information during learning, its encoding and stabilization, and the recall of stored memories. Besides, we also investigated the effect of SD in the extinction of fear memory and a possible state-dependent learning induced by this manipulation. For each task (contextual or tone fear conditioning, animals were trained and then distributed into control, not sleep-deprived (CTL and SD groups, the latter being submitted to the modified multiple platform paradigm for 96 h. Subsets of eight rats in each group/experiment were submitted to the test of the tasks, either immediately or at different time intervals after SD. The results indicated that a pre-, but not post-training SD impaired recall in the contextual and tone fear conditioning; b this impairment was not state-dependent; c in the contextual fear conditioning, pre-test SD prevented extinction of the learned task. Overall, these results suggest that SD interferes with acquisition, recall and extinction, but not necessarily with consolidation of emotional memory.
Rossi, Vanessa Contatto; Tiba, Paula Ayako; Moreira, Karin Di Monteiro; Ferreira, Tatiana Lima; Oliveira, Maria Gabriela Menezes; Suchecki, Deborah
Numerous studies show that sleep deprivation (SD) impacts negatively on cognitive processes, including learning and memory. Memory formation encompasses distinct phases of which acquisition, consolidation and retrieval are better known. Previous studies with pre-training SD induced by the platform method have shown impairment in fear conditioning tasks. Nonetheless, pre-training manipulations do not allow the distinction between effects on acquisition and/or consolidation, interfering, ultimately, on recall of/performance in the task. In the present study, animals were first trained in contextual and tone fear conditioning (TFC) tasks and then submitted to SD with the purpose to evaluate the effect of this manipulation on different stages of the learning process, e.g., in the uptake of (new) information during learning, its encoding and stabilization, and the recall of stored memories. Besides, we also investigated the effect of SD in the extinction of fear memory and a possible state-dependent learning induced by this manipulation. For each task (contextual or TFC), animals were trained and then distributed into control, not sleep-deprived (CTL) and SD groups, the latter being submitted to the modified multiple platform paradigm for 96 h. Subsets of eight rats in each group/experiment were submitted to the test of the tasks, either immediately or at different time intervals after SD. The results indicated that (a) pre- but not post-training SD impaired recall in the contextual and TFC; (b) this impairment was not state-dependent; and (c) in the contextual fear conditioning (CFC), pre-test SD prevented extinction of the learned task. Overall, these results suggest that SD interferes with acquisition, recall and extinction, but not necessarily with consolidation of emotional memory.
Craddock, Matt; Martinovic, Jasna; Müller, Matthias M
Visual object processing may follow a coarse-to-fine sequence imposed by fast processing of low spatial frequencies (LSF) and slow processing of high spatial frequencies (HSF). Objects can be categorized at varying levels of specificity: the superordinate (e.g. animal), the basic (e.g. dog), or the subordinate (e.g. Border Collie). We tested whether superordinate and more specific categorization depend on different spatial frequency ranges, and whether any such dependencies might be revealed by or influence signals recorded using EEG. We used event-related potentials (ERPs) and time-frequency (TF) analysis to examine the time course of object processing while participants performed either a grammatical gender-classification task (which generally forces basic-level categorization) or a living/non-living judgement (superordinate categorization) on everyday, real-life objects. Objects were filtered to contain only HSF or LSF. We found a greater positivity and greater negativity for HSF than for LSF pictures in the P1 and N1 respectively, but no effects of task on either component. A later, fronto-central negativity (N350) was more negative in the gender-classification task than the superordinate categorization task, which may indicate that this component relates to semantic or syntactic processing. We found no significant effects of task or spatial frequency on evoked or total gamma band responses. Our results demonstrate early differences in processing of HSF and LSF content that were not modulated by categorization task, with later responses reflecting such higher-level cognitive factors.
Full Text Available Visual object processing may follow a coarse-to-fine sequence imposed by fast processing of low spatial frequencies (LSF and slow processing of high spatial frequencies (HSF. Objects can be categorized at varying levels of specificity: the superordinate (e.g. animal, the basic (e.g. dog, or the subordinate (e.g. Border Collie. We tested whether superordinate and more specific categorization depend on different spatial frequency ranges, and whether any such dependencies might be revealed by or influence signals recorded using EEG. We used event-related potentials (ERPs and time-frequency (TF analysis to examine the time course of object processing while participants performed either a grammatical gender-classification task (which generally forces basic-level categorization or a living/non-living judgement (superordinate categorization on everyday, real-life objects. Objects were filtered to contain only HSF or LSF. We found a greater positivity and greater negativity for HSF than for LSF pictures in the P1 and N1 respectively, but no effects of task on either component. A later, fronto-central negativity (N350 was more negative in the gender-classification task than the superordinate categorization task, which may indicate that this component relates to semantic or syntactic processing. We found no significant effects of task or spatial frequency on evoked or total gamma band responses. Our results demonstrate early differences in processing of HSF and LSF content that were not modulated by categorization task, with later responses reflecting such higher-level cognitive factors.
D'Ascenzo, Stefania; Rubichi, Sandro; Di Gregorio, Gianluca; Tommasi, Luca
Our actions are influenced by the social context in which they are performed, specifically it has been shown that observing others' actions influences the execution of the same action. In the present study, we examined whether and to what extent observers are influenced by the presence and performance of another person in a visual spatial task, using a line bisection paradigm in which two participants performed the task in turns while sitting in front of each other. Thirty pairs of participants took part in the experiment, which was divided into a non-social and a social session. In the latter, each participant was alternately an agent (performing the task) and an observer (evaluating covertly the other's performance). Results show that the leftward bias (pseudoneglect) in the line bisection task was significantly reduced when the task was performed in the social session, although the bias (both in the non-social and in the social session) was observed only when the left hand was used. Moreover, a dissociation between performance and perception was observed: the judgment given to the other's performance (which visually deviated in the direction opposite to one's own bias due to the spatial arrangement of participants and their facing vantage points) was significantly in disagreement with one's own performance. Overall, our results demonstrate that the other's presence influences our own action during a line bisection task and that spatial judgments on other's performance can modulate our own performance, even when coordination between participants is not required. Results are discussed in relation to social influence and perspective taking in the general framework of interpersonal resonance. Copyright © 2016 Elsevier B.V. All rights reserved.
Koh, Ming Teng; Rosenzweig-Lipson, Sharon; Gallagher, Michela
A condition of excess activity in the hippocampal formation is observed in the aging brain and in conditions that confer additional risk during aging for Alzheimer's disease. Compounds that act as positive allosteric modulators at GABA(A) α5 receptors might be useful in targeting this condition because GABA(A) α5 receptors mediate tonic inhibition of principal neurons in the affected network. While agents to improve cognitive function in the past focused on inverse agonists, which are negative allosteric modulators at GABA(A) α5 receptors, research supporting that approach used only young animals and predated current evidence for excessive hippocampal activity in age-related conditions of cognitive impairment. Here, we used two compounds, Compound 44 [6,6-dimethyl-3-(3-hydroxypropyl)thio-1-(thiazol-2-yl)-6,7-dihydro-2-benzothiophen-4(5H)-one] and Compound 6 [methyl 3,5-diphenylpyridazine-4-carboxylate], with functional activity as potentiators of γ-aminobutyric acid at GABA(A) α5 receptors, to test their ability to improve hippocampal-dependent memory in aged rats with identified cognitive impairment. Improvement was obtained in aged rats across protocols differing in motivational and performance demands and across varying retention intervals. Significant memory improvement occurred after either intracereboventricular infusion with Compound 44 (100 μg) in a water maze task or systemic administration with Compound 6 (3 mg/kg) in a radial arm maze task. Furthermore, systemic administration improved behavioral performance at dosing shown to provide drug exposure in the brain and in vivo receptor occupancy in the hippocampus. These data suggest a novel approach to improve neural network function in clinical conditions of excess hippocampal activity. This article is part of a Special Issue entitled 'Cognitive Enhancers'. Copyright © 2012 Elsevier Ltd. All rights reserved.
Full Text Available In task-switching paradigms, reaction times (RTs switch cost (SC and the neural correlates underlying the SC are affected by different preparation intervals. However, little is known about the effect of the preparation interval on the repetition processes in task-switching. To examine this effect we utilized a cued task-switching paradigm with long sequences of repeated trials. Response-stimulus intervals (RSI and cue-stimulus intervals (CSI were manipulated in short and long conditions. Electroencephalography (EEG and behavioral data were recorded. We found that with increasing repetitions, RTs were faster in the short CSI conditions, while P3 amplitudes decreased in the LS (long RSI and short CSI conditions. Positive correlations between RT benefit and P3 activation decrease (repeat 1 minus repeat 5, and between the slope of the RT and P3 regression lines were observed only in the LS condition. Our findings suggest that differential preparation intervals modulate repetition processes in task switching.
Bogon, Johanna; Eisenbarth, Hedwig; Landgraf, Steffen; Dreisbach, Gesine
Vocal events offer not only semantic-linguistic content but also information about the identity and the emotional-motivational state of the speaker. Furthermore, most vocal events have implications for our actions and therefore include action-related features. But the relevance and irrelevance of vocal features varies from task to task. The present study investigates binding processes for perceptual and action-related features of spoken words and their modulation by the task representation of the listener. Participants reacted with two response keys to eight different words spoken by a male or a female voice (Experiment 1) or spoken by an angry or neutral male voice (Experiment 2). There were two instruction conditions: half of participants learned eight stimulus-response mappings by rote (SR), and half of participants applied a binary task rule (TR). In both experiments, SR instructed participants showed clear evidence for binding processes between voice and response features indicated by an interaction between the irrelevant voice feature and the response. By contrast, as indicated by a three-way interaction with instruction, no such binding was found in the TR instructed group. These results are suggestive of binding and shielding as two adaptive mechanisms that ensure successful communication and action in a dynamic social environment.
Gaigg, Sebastian B; Bowler, Dermot M; Gardiner, John M
Considerable evidence suggests that the episodic memory system operates abnormally in autism spectrum disorder (ASD) whereas the functions of the semantic memory system are relatively preserved. Here we show that the same dissociation also applies to the domain of order memory. We asked adult participants to order the names of famous historical figures either according to their chronological order in history (probing semantic memory) or according to a random sequence shown once on a screen (probing episodic memory). As predicted, adults with ASD performed less well than age- and IQ-matched comparison individuals only on the episodic task. This observation is of considerable importance in the context of developmental theory because semantic and episodic order memory abilities can be dissociated in typically developing infants before they reach the age at which the behavioural markers associated with ASD are first apparent. This raises the possibility that early emerging memory abnormalities play a role in shaping the developmental trajectory of the disorder. We discuss the broader implications of this possibility and highlight the urgent need for greater scrutiny of memory competences in ASD early in development.
Chambon, Caroline; Jatzke, Claudia; Wegener, Nico; Gravius, Andreas; Danysz, Wojciech
Benzylquinolone carboxylic acid (BQCA) is a recently described cholinergic muscarinic M(1) receptor positive allosteric modulator having potential as cognitive enhancer in dementia. The present study focused on the characterisation of BQCA's mode of action in relation to positive effects on memory and side-effects in an animal model. To get insight into this mode of action, in vitro receptor potency/left shift experiments in cells stably expressing the rat's M(1) receptor were performed. They revealed an inflection point value of BQCA corresponding to 306nM, and potentiation of the agonist response up to 47-fold in presence of 10μM of BQCA. In vivo, brain microdialysis showed a maximal brain level of 270nM, 40min after i.p. administration at 10mg/kg. Based on in vitro data obtained with this dose, it can be concluded that BQCA reaches brain levels which should potentiate the agonist response about 4-fold. Behavioural data confirmed that BQCA used at 10mg/kg attenuated scopolamine-induced memory deficit in a spontaneous alternation task. Moreover, BQCA showed no side effect at 10mg/kg and above in spontaneous locomotion and salivation tests. The profile of BQCA observed in the present study displays a clear advantage over the M(1)-M(3) agonist cevimeline. The present data show the therapeutic potential of the M(1) receptor positive allosteric modulator BQCA for the treatment of memory deficits observed in Alzheimer's disease. Copyright © 2012. Published by Elsevier B.V.
Monds, Lauren A; Paterson, Helen M; Kemp, Richard I
Many eyewitness memory situations involve negative and distressing events; however, many studies investigating "false memory" phenomena use neutral stimuli only. The aim of the present study was to determine how both the Deese-Roediger-McDermott (DRM) procedure and the Misinformation Effect Paradigm tasks were related to each other using distressing and neutral stimuli. Participants completed the DRM (with negative and neutral word lists) and viewed a distressing or neutral film. Misinformation for the film was introduced and memory was assessed. Film accuracy and misinformation susceptibility were found to be greater for those who viewed the distressing film relative to the neutral film. Accuracy responses on both tasks were related, however, susceptibility to the DRM illusion and Misinformation Effect were not. The misinformation findings support the Paradoxical Negative Emotion (PNE) hypothesis that negative stimuli will lead to remembering more accurate details but also greater likelihood of memory distortion. However, the PNE hypothesis was not supported for the DRM results. The findings also suggest that the DRM and Misinformation tasks are not equivalent and may have differences in underlying mechanisms. Future research should focus on more ecologically valid methods of assessing false memory.
Burggraaf, Rudolf; Frens, Maarten A; Hooge, Ignace T C; van der Geest, Jos N
Cognitive functions mature at different points in time between birth and adulthood. Of these functions, visuospatial skills, such as spatial memory and part-to-whole organization, have often been tested in children and adults but have been less frequently evaluated during adolescence. We studied visuospatial memory and ability during this critical developmental period, as well as the correlation between these abilities, in a large group of 330 participants (aged 11 to 20 years, 55% male). To assess visuospatial memory, the participants were asked to memorize and reproduce sequences of random locations within a grid using a computer. Visuospatial ability was tested using a variation of the Design Organization Test (DOT). In this paper-and-pencil test, the participants had one minute to reproduce as many visual patterns as possible using a numerical code. On the memory task, compared with younger participants, older participants correctly reproduced more locations overall and longer sequences of locations, made fewer mistakes and needed less time to reproduce the sequences. In the visuospatial ability task, the number of correctly reproduced patterns increased with age. We show that both visuospatial memory and ability improve significantly throughout adolescence and that performance on both tasks is significantly correlated.
Chen, Hung-Yu; Gilmore, Adrian W; Nelson, Steven M; McDermott, Kathleen B
What brain regions underlie retrieval from episodic memory? The bulk of research addressing this question with fMRI has relied upon recognition memory for materials encoded within the laboratory. Another, less dominant tradition has used autobiographical methods, whereby people recall events from their lifetime, often after being cued with words or pictures. The current study addresses how the neural substrates of successful memory retrieval differed as a function of the targeted memory when the experimental parameters were held constant in the two conditions (except for instructions). Human participants studied a set of scenes and then took two types of memory test while undergoing fMRI scanning. In one condition (the picture memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it was recollected from the prior study episode. In a second condition (the life memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it reminded them of a specific event from their preexperimental lifetime. An examination of successful retrieval (yes responses) for recently studied scenes for the two test types revealed pronounced differences; that is, autobiographical retrieval instantiated with the life memory test preferentially activated the default mode network, whereas hits in the picture memory test preferentially engaged the parietal memory network as well as portions of the frontoparietal control network. When experimental cueing parameters are held constant, the neural underpinnings of successful memory retrieval differ when remembering life events and recently learned events. SIGNIFICANCE STATEMENT Episodic memory is often discussed as a solitary construct. However, experimental traditions examining episodic memory use very different approaches, and these are rarely compared to one another. When the neural correlates associated with each approach have been directly contrasted, results have varied considerably
Tang Zhen-Jie; Li Rong; Yin Jiang
A composition-modulated (HfO 2 ) x (Al 2 O3) 1−x charge trapping layer is proposed for charge trap flash memory by controlling the Al atom content to form a peak and valley shaped band gap. It is found that the memory device using the composition-modulated (HfO 2 ) x (Al 2 O 3 ) 1−x as the charge trapping layer exhibits a larger memory window of 11.5 V, improves data retention even at high temperature, and enhances the program/erase speed. Improvements of the memory characteristics are attributed to the special band-gap structure resulting from the composition-modulated trapping layer. Therefore, the composition-modulated charge trapping layer may be useful in future nonvolatile flash memory device application. (condensed matter: electronic structure, electrical, magnetic, and optical properties)
Botting, Nicola; Psarou, Popi; Caplin, Tamara; Nevin, Laura
Background and Design: In recent years, evidence has emerged that suggests specific language impairment (SLI) does not exclusively affect linguistic skill. Studies have revealed memory difficulties, including those measured using nonverbal tasks. However, there has been relatively little research into the nature of the verbal/nonverbal boundaries…
Meier, Matt E.; Smeekens, Bridget A.; Silvia, Paul J.; Kwapil, Thomas R.; Kane, Michael J.
The association between working memory capacity (WMC) and the antisaccade task, which requires subjects to move their eyes and attention away from a strong visual cue, supports the claim that WMC is partially an attentional construct (Kane, Bleckley, Conway, & Engle, 2001; Unsworth, Schrock, & Engle, 2004). Specifically, the…
Cordeira, Joshua; Kolluru, Sai Saroja; Rosenblatt, Heather; Kry, Jenny; Strecker, Robert E; McCarley, Robert W
Females are an under-represented research model and the mechanisms through which sleep loss impairs cognition are not clear. Since levels of reproductive hormones and the estrous cycle are sensitive to sleep loss and necessary for learning and memory, we hypothesized that sleep deprivation impacts learning and memory in female mice by interfering with the estrous cycle. We used the object recognition task to assess learning and memory in female mice during separate phases of the estrous cycle and after sleep loss. Mice in metestrus/diestrus attended to sample objects less than mice in proestrus/estrus during object acquisition, the first phase of the object recognition task. Subsequently, during the recognition phase of the task, only mice in proestrus/estrus displayed a preference for the novel object. Sleep deprivation for 12h immediately before the object recognition task reduced time attending to sample objects and novel object preference for mice in proestrus/estrus, without changing length of the estrous cycle. These results show that sleep deprived mice in proestrus/estrus had learning deficits and memory impairments, like mice in metestrus/diestrus. Since sleep deprivation did not disrupt the estrous cycle, however, results did not support the hypothesis. Cognitive impairments due to acute sleep loss were not due to alterations to the estrous cycle. Copyright © 2017 Elsevier B.V. All rights reserved.
Baudouin, Alexia; Clarys, David; Vanneste, Sandrine; Isingrini, Michel
The aim of the present study was to examine executive dysfunctioning and decreased processing speed as potential mediators of age-related differences in episodic memory. We compared the performances of young and elderly adults in a free-recall task. Participants were also given tests to measure executive functions and perceptual processing speed…
Morey, Candice Coker; Cowan, Nelson; Morey, Richard D.; Rouder, Jeffery N.
Prominent roles for general attention resources are posited in many models of working memory, but the manner in which these can be allocated differs between models or is not sufficiently specified. We varied the payoffs for correct responses in two temporally-overlapping recognition tasks, a visual
Castro-Fornieles, Josefina; Caldu, Xavier; Andres-Perpina, Susana; Lazaro, Luisa; Bargallo, Nuria; Falcon, Carles; Plana, Maria Teresa; Junque, Carme
Structural and functional brain abnormalities have been described in anorexia nervosa (AN). The objective of this study was to examine whether there is abnormal regional brain activation during a working memory task not associated with any emotional stimuli in adolescent patients with anorexia and to detect possible changes after weight recovery.…
Lejbak, Lisa; Crossley, Margaret; Vrbancic, Mirna
Sex-related differences have been reported for performance and neural substrates on some working memory measures that carry a high cognitive load, including the popular n-back neuroimaging paradigm. Despite some evidence of a sex effect on the task, the influence of sex on performance represents a potential confound in neuroimaging research. The…
Michinov, Estelle; Michinov, Nicolas; Huguet, Pascal
This experiment was designed to examine the effects of gender role and task content on performance in learning dyads and to test the potential mediator effect of an intragroup process related to transactive memory. A total of 44 same-gender dyads participated in the study and were asked to collaborate on a stereotypically masculine or feminine…
Ferguson, Scott; Friedland, Daniel; Woodberry, Emma
Prospective memory is a common deficit following brain injury that can reduce an individuals' ability to complete everyday tasks. The smartphone is a device that may compensate for these difficulties using the calendar's prompting function. Reminders can be programmed remotely using email to phone synchronization. To explore whether smartphone reminders help people complete pre-identified tasks as compared to when reminders are not provided. An ABAB case series design compared reminder present vs. reminder absent phases with regards completion of pre-set tasks. Six participants aged 24-55 with Acquired Brain Injury (ABI) and five caregivers participated in the study. Both completed a series of questionnaires looking at the impact of the smartphone reminders on everyday memory functioning at pre, post and follow-up. A 3-month follow-up questionnaire assessed continued use of the system. There was a significant improvement in task completion rates when smartphone reminders were provided. A thematic analysis identified that smartphone reminders improved independence, confidence in coping with memory difficulties and general mood. All participants were still using the system at 3-month follow-up. Smartphone reminders may provide a cost-effective, accessible and non-stigmatizing tool for participants to compensate for prospective memory difficulties.
Ardeshiri, Motahareh Rouhi; Hosseinmardi, Narges; Akbari, Esmaeil
There is an extensive evidence concerning basolateral amygdala (BLA) function to hippocampal memory processing. However, few researches have addressed the orexinergic system roles in this modulation. Then, the present study aims at investigating the action of orexin 1 and 2 receptors in BLA on passive avoidance (PA) learning. Wistar male rats (n=79) were trained to avoid foot shock in one type of PA task. The rats were injected bilaterally into BLA, a selective orexin 1 receptor antagonist, SB-334867-A (3, 6, 12μg/0.5μl), and an orexin 2 receptor antagonist, TCS-OX2-29 (2.5, 5, 10μg/0.5μl), after training or before retrieval of the inhibitory avoidance task. Control rats received dimethyl sulfoxide at the same volume. The amount of learning was assessed 24h later. The time of the first entrance to the dark compartment and the total time spending in the light compartment were measured as criteria for the avoidance memory. The results showed that consolidation and retrieval were significantly impaired by SB-334867-A administration into BLA in 3, 6 and 12μg/0.5μl. However, TCS-OX2-29 in 2.5μg/0.5μl could not influence neither consolidation nor retrieval. The TCS-OX2-29 administration into BLA impaired memory retrieval in 5 and 10μg/0/5μl but not the consolidation. It gives the impression that orexinergic system of the BLA plays an important role in regulation of memory processing and learning in the rats. Copyright © 2017 Elsevier Inc. All rights reserved.
Hampson, Robert E.; Song, Dong; Opris, Ioan; Santos, Lucas M.; Shin, Dae C.; Gerhardt, Greg A.; Marmarelis, Vasilis Z.; Berger, Theodore W.; Deadwyler, Sam A.
Objective. Memory accuracy is a major problem in human disease and is the primary factor that defines Alzheimer’s, ageing and dementia resulting from impaired hippocampal function in the medial temporal lobe. Development of a hippocampal memory neuroprosthesis that facilitates normal memory encoding in nonhuman primates (NHPs) could provide the basis for improving memory in human disease states. Approach. NHPs trained to perform a short-term delayed match-to-sample (DMS) memory task were examined with multi-neuron recordings from synaptically connected hippocampal cell fields, CA1 and CA3. Recordings were analyzed utilizing a previously developed nonlinear multi-input multi-output (MIMO) neuroprosthetic model, capable of extracting CA3-to-CA1 spatiotemporal firing patterns during DMS performance. Main results. The MIMO model verified that specific CA3-to-CA1 firing patterns were critical for the successful encoding of sample phase information on more difficult DMS trials. This was validated by the delivery of successful MIMO-derived encoding patterns via electrical stimulation to the same CA1 recording locations during the sample phase which facilitated task performance in the subsequent, delayed match phase, on difficult trials that required more precise encoding of sample information. Significance. These findings provide the first successful application of a neuroprosthesis designed to enhance and/or repair memory encoding in primate brain.
Burton, S; Murphy, D; Qureshi, U; Sutton, P; O'Keefe, J
Rats transmit information to each other about which foods are safe to eat. If a rat smells a food odor on the breath of another rat, it is subsequently more likely to eat that food than an alternative. Work by Galef et al. (1988) has shown that the observer rat forms an association between two olfactory stimuli on the breath of the demonstrator rat that has eaten the food, the food odor and carbon disulphide, which is normally present in the rat breath. Bunsey and Eichenbaum (1995) claimed that the hippocampus/subicular region is required for the long-term retention of this nonspatial form of associative memory on the basis that combined lesions of the hippocampus and subiculum produced a deficit, but lesions of either structure alone did not. We report here a failure to repeat this finding. Rats with either combined lesions of the hippocampus and subiculum or with amygdala lesions were tested on their ability to remember this association either immediately (testing short-term memory) or after a 24 hr delay (testing long-term memory). Neither lesion group exhibited significant memory deficits on this nonspatial associative task at either test interval. In contrast, a deficit was observed on a spatial memory task (forced-choice alternation t-maze) for animals with combined lesions of the hippocampus and subiculum. These results contradict the findings of Bunsey and Eichenbaum (1995) and support the idea that the hippocampus/subicular region is not required for this nonspatial associative memory.
The pattern of the mood-congruent effect in an autobiographical memory recall task was investigated. Each subject was randomly assigned to one of three experimental conditions: positive mood, negative mood (induced with music), and control groups (no specific mood). Subjects were then presented with a word at a time from a list of trait words, which were pleasant or unpleasant. They decided whether they could recall any of their autobiographical memories related to the word, and responded with "yes" or "no" buttons as rapidly and accurately as possible. After the task, they were given five minutes for an incidental free recall test. Results indicated that the mood-congruent effect was found regardless of whether there was an autobiographical memory related to the word or not in both positive and negative mood states. The effect of moods on self-relevant information processing was discussed.
Hsu, Chien-Chang; Cheng, Ching-Wen; Chiu, Yi-Shiuan
Electroencephalograms can record wave variations in any brain activity. Beta waves are produced when an external stimulus induces logical thinking, computation, and reasoning during consciousness. This work uses the beta wave of major scale working memory N-back tasks to analyze the differences between young musicians and non-musicians. After the feature analysis uses signal filtering, Hilbert-Huang transformation, and feature extraction methods to identify differences, k-means clustering algorithm are used to group them into different clusters. The results of feature analysis showed that beta waves significantly differ between young musicians and non-musicians from the low memory load of working memory task. Copyright © 2017 Elsevier B.V. All rights reserved.
Nielsen, Trine Damgaard; Larsen, Dorrit Bjerg; Hansen, Suzanne Lisbet
deficit in female Lister hooded rats in teh novel object recognition (NOR) task. Here we show that positive modulation of AMPA receptor (AMPAR) mediated glutamate transmission alleviates cognitive deficits induced by sub-chronic PCP treatment. Female Lister hooded rats were treated sub......Cognitive deficits are a major clinical unmet need in schizophrenia. The psychotomimetic drug phencyclicline (PCP) is widely applied in rodents to mimic symptoms of schizophrenia, including cognitive deficits. Precious studies have shown that sub-chronic PCP induces an enduring episodic memory......-cbronic PCP treatment induced a significant decrease in the discrimination index (DI) and both ampakines CX546 and CX516 were able to reverse this diruption of object memory in rats in the novel object recognition task. These data suggest that positive AMPAR modulation may represent a mechanism for treatment...
Xie, Meilan; Yan, Jie; He, Chao; Yang, Li; Tan, Gang; Li, Chao; Hu, Zhian; Wang, Jiali
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.
Clayton, N S
Food-storing birds, for example, marsh tits, Parus palustris, use memory to retrieve stored food and have a larger hippocampus relative to the rest of the telencephalon than do species that store little or no food such as the blue tit, P. caeruleus. The difference between food storers and nonstorers in relative hippocampal volume occurs after the young birds have fledged from the nest and is dependent upon some aspect of memory for retrieving caches of stored food. To test whether or not species differences in memory and volumetric changes in the hippocampus could be triggered by experience of memory tasks other than retrieval of stored food, groups of hand-raised marsh tits and blue tits were tested between days 35 and 192 posthatch on a one-trial associative memory task in which they were rewarded in phase II for returning to the feeder where they had eaten part of a peanut 20 min earlier. No species differences were found when the peanut was visible in phase I, but when the peanut was hidden in phase I, marsh tits performed better than blue tits, irrespective of whether or not they had had previous experience of storing and retrieving food. In dissociation trials (transformed array of feeders), marsh tits with food-storing experience responded preferentially to spatial cues, whereas blue tits responded equally to both spatial position and object-specific cues. These species differences are also found in wild-caught adults. However, marsh tits without food-storing experience responded equally to both spatial position and object-specific cues, which suggests that experience of storing and/or retrieving caches is required in order for marsh tits to develop the spatial preference seen in adult food storers. Both marsh tits with experience of the one-trial associative memory task and those that had also had food-storing experience had larger relative hippocampal volumes than did controls, independent of age. Of the marsh tits trained on the one-trial associative
van de Weijer, E.; Kroesbergen, E.H.; Prast, E.J.; van Luit, J.E.H.
Working memory is an important predictor of academic performance, and of math performance in particular. Most working memory tasks depend on one-to-one administration by a testing assistant, which makes the use of such tasks in large-scale studies time-consuming and costly. Therefore, an online,
Mahy, Caitlin E V; Voigt, Babett; Ballhausen, Nicola; Schnitzspahn, Katharina; Ellis, Judi; Kliegel, Matthias
The present study investigated whether developmental changes in cognitive control may underlie improvements of time-based prospective memory. Five-, 7-, 9-, and 11-year-olds (N = 166) completed a driving simulation task (ongoing task) in which they had to refuel their vehicle at specific points in time (PM task). The availability of cognitive control resources was experimentally manipulated by imposing a secondary task that required divided attention. Children completed the driving simulation task both in a full-attention condition and a divided-attention condition where they had to carry out a secondary task. Results revealed that older children performed better than younger children on the ongoing task and PM task. Children performed worse on the ongoing and PM tasks in the divided-attention condition compared to the full-attention condition. With respect to time monitoring in the final interval prior to the PM target, divided attention interacted with age such that older children's time monitoring was more negatively affected by the secondary task compared to younger children. Results are discussed in terms of developmental shifts from reactive to proactive monitoring strategies.
Episodic memory retrieval is assumed to be associated with the tonic cognitive state of retrieval mode. Despite extensive research into the neurophysiological correlates of retrieval mode, as of yet, relatively little is known about its functional significance. The present event-related potential (ERP) study was aimed at examining the impact of retrieval mode on the specificity of memory content retrieved in the course of familiarity and recollection processes. In two experiments, participants performed a recognition memory inclusion task in which they had to distinguish identically repeated and re-colored versions of study items from new items. In Experiment 1, participants had to alternate between the episodic memory task and a semantic task requiring a natural/artificial decision. In Experiment 2, the two tasks were instead performed in separate blocks. ERPs locked to the preparatory cues in the test phases indicated that participants did not establish retrieval mode on switch trials in Experiment 1. In the absence of retrieval mode, neither type of studied item elicited ERP correlates of familiarity-based retrieval (FN400). Recollection-related late positive complex (LPC) old/new effects emerged only for identically repeated but not for conceptually identical but perceptually changed versions of study items. With blocked retrieval in Experiment 2, both types of old items instead elicited equivalent FN400 and LPC old/new effects. The LPC data indicate that retrieval mode may play an important role in the successful recollection of conceptual stimulus information. The FN400 results additionally suggest that task switching may have a detrimental effect on familiarity-based memory retrieval. Copyright © 2017 Elsevier B.V. All rights reserved.
Sinke, Christopher; Forkmann, Katarina; Schmidt, Katharina; Wiech, Katja; Bingel, Ulrike
Over the recent years, neuroimaging studies have investigated the neural mechanisms underlying the influence of expectations on perception. However, it seems equally reasonable to assume that expectations impact cognitive functions. Here we used fMRI to explore the role of expectations on task performance and its underlying neural mechanisms. 43 healthy participants were randomly assigned to two groups. Using verbal instructions, group 1 was led to believe that pain enhances task performance while group 2 was instructed that pain hampers their performance. All participants performed a Rapid-Serial-Visual-Presentation (RSVP) Task (target detection and short-term memory component) with or without concomitant painful heat stimulation during 3T fMRI scanning. As hypothesized, short-term memory performance showed an interaction between painful stimulation and expectation. Positive expectations induced stronger neural activation in the right inferior parietal cortex (IPC) during painful stimulation than negative expectation. Moreover, IPC displayed differential functional coupling with the left inferior occipital cortex under pain as a function of expectancy. Our data show that an individual's expectation can influence cognitive performance in a visual short-term memory task which is associated with activity and connectivity changes in brain areas implicated in attentional processing and task performance. Copyright © 2016. Published by Elsevier Ltd.
Kuschpel, Maxim S; Liu, Shuyan; Schad, Daniel J; Heinzel, Stephan; Heinz, Andreas; Rapp, Michael A
The interruption of learning processes by breaks filled with diverse activities is common in everyday life. We investigated the effects of active computer gaming and passive relaxation (rest and music) breaks on working memory performance. Young adults were exposed to breaks involving (i) eyes-open resting, (ii) listening to music and (iii) playing the video game "Angry Birds" before performing the n-back working memory task. Based on linear mixed-effects modeling, we found that playing the "Angry Birds" video game during a short learning break led to a decline in task performance over the course of the task as compared to eyes-open resting and listening to music, although overall task performance was not impaired. This effect was associated with high levels of daily mind wandering and low self-reported ability to concentrate. These findings indicate that video games can negatively affect working memory performance over time when played in between learning tasks. We suggest further investigation of these effects because of their relevance to everyday activity.
Maxim S Kuschpel
Full Text Available The interruption of learning processes by breaks filled with diverse activities is common in everyday life. We investigated the effects of active computer gaming and passive relaxation (rest and music breaks on working memory performance. Young adults were exposed to breaks involving (i eyes-open resting, (ii listening to music and (iii playing the video game Angry Birds before performing the n-back working memory task. Based on linear mixed-effects modeling, we found that playing the Angry Birds video game during a short learning break led to a decline in task performance over the course of the task as compared to eyes-open resting and listening to music, although overall task performance was not impaired. This effect was associated with high levels of daily mind wandering and low self-reported ability to concentrate. These findings indicate that video games can negatively affect working memory performance over time when played in between learning tasks. We suggest further investigation of these effects because of their relevance to everyday activity.
Full Text Available Walking, although a largely automatic process, is controlled by the cortex and the spinal cord; with corrective reflexes modulated through integration of neural signals from central and peripheral inputs at supraspinal level throughout the gait cycle. However the full mechanism is not described. In this study we used an additional cognitive task to interfere with the automatic processing during walking in order to explore the neural mechanisms involved in healthy young adults. Participants were asked to walk on a treadmill at two speeds, both with and without additional cognitive load. We evaluated the impact of speed and cognitive load by analysing activity of the pre-frontal cortex (PFC using functional Near-Infrared Spectroscopy (fNIRS alongside with spinal cord reflex activity measured by soleus H-reflex amplitude and gait changes obtained by using an inertial measuring unit. Repeated measures ANOVA revealed that fNIRS Oxy-Hb concentrations significantly increased in the PFC with dual task (walking while performing a cognitive task compared to a single talk only (walking (p< 0.05. PFC activity was unaffected by increases of walking speed. H-reflex amplitude and gait variables did not change in response to either dual task or increases of walking speed. When walking under additional cognitive load we observed that participants adapted by using greater activity in the PFC, but that this adaption did not detrimentally affect H-reflex amplitude or gait variables. Our findings suggests that in a healthy young population central mechanisms (PFC are activated in response to cognitive loads but that H-reflex activity and gait performance can successfully be maintained. This study provides insight in the mechanisms behind healthy individuals safely performing dual task walking
Gang, G. J.; Siewerdsen, J. H.; Stayman, J. W.
Purpose: This work presents a task-driven joint optimization of fluence field modulation (FFM) and regularization in quadratic penalized-likelihood (PL) reconstruction. Conventional FFM strategies proposed for filtered-backprojection (FBP) are evaluated in the context of PL reconstruction for comparison. Methods: We present a task-driven framework that leverages prior knowledge of the patient anatomy and imaging task to identify FFM and regularization. We adopted a maxi-min objective that ensures a minimum level of detectability index (d') across sample locations in the image volume. The FFM designs were parameterized by 2D Gaussian basis functions to reduce dimensionality of the optimization and basis function coefficients were estimated using the covariance matrix adaptation evolutionary strategy (CMA-ES) algorithm. The FFM was jointly optimized with both space-invariant and spatially-varying regularization strength (β) - the former via an exhaustive search through discrete values and the latter using an alternating optimization where β was exhaustively optimized locally and interpolated to form a spatially-varying map. Results: The optimal FFM inverts as β increases, demonstrating the importance of a joint optimization. For the task and object investigated, the optimal FFM assigns more fluence through less attenuating views, counter to conventional FFM schemes proposed for FBP. The maxi-min objective homogenizes detectability throughout the image and achieves a higher minimum detectability than conventional FFM strategies. Conclusions: The task-driven FFM designs found in this work are counter to conventional patterns for FBP and yield better performance in terms of the maxi-min objective, suggesting opportunities for improved image quality and/or dose reduction when model-based reconstructions are applied in conjunction with FFM.
Henrard, Sébastien; Van Daele, Agnès
Many studies have shown that being bilingual presents an advantage in executive control. However, it appears that knowing two (or more) languages is not enough to improve executive control. According to the adaptive control hypothesis (Green and Abutalebi, 2013), the interactional context in which bilinguals behave is a key factor that modulates cognitive advantage in executive control. Translation and simultaneous interpretation are performed in a dual-language context: professional bi- and multilinguals use two or more languages within the same context (at work). Simultaneous interpretation differs from translation though, because of its higher level of time pressure, which increases the cognitive demands on executive control. The main objective of the present study is to investigate the relationship between simultaneous interpretation and some aspects of executive control. To this end, we compare the performance of three groups (60 interpreters, 60 translators, and 60 monolinguals) in five computerized tasks designed to assess different executive processes as well as the speed of information processing. The results show that the interpreters perform better than the monolinguals in all tasks and better than the translators in all tasks except for the one designed to assess flexibility. The results also show that the age variable does not have the same effect on performance in tasks designed to assess updating, flexibility, and resistance of proactive inhibition in bilinguals (both interpreters and translators), or in tasks designed to assess the speed of information processing and inhibition of a prepotent response in interpreters only. In addition to the advantage that being bilingual presents in some aspects of executive control, the results suggest that interpreters have an additional advantage that may be explained by the characteristics of their work activity (especially heavy time pressure) and by how much experience they have in this activity (in terms of
Tomasi, D.; Caparelli, E.C.; Chang, L.; Ernst, T.
Scanner noise during functional magnetic resonance imaging (fMRI) may interfere with brain function and change blood oxygenation level dependent (BOLD) signals, a problem that generally worsens at the higher field strengths. Therefore, we studied the effect of increased acoustic noise on fMRI during verbal working memory (WM) processing. The sound pressure level of scanner noise was increased by 12 dBA from “Quiet” to “Loud” echo planar imaging (EPI) scans by utilizing resonant vibration modes of the gradient coil. A WM paradigm with graded levels of task difficulty was used to further access WM-load. Increased scanner noise produced increased BOLD responses (percent signal change) bilaterally in the cerebellum, inferior (IFG), medial (medFG), and superior (SFG) frontal, fusiform (FusG), and the lingual (LG) gyri, and decreased BOLD responses bilaterally in the anterior cingulate gyrus (ACG) and the putamen. This finding suggests greater recruitment of attention resources in these brain regions, probably to compensate for interference due to louder scanner noise. Increased working memory load increased the BOLD signals in IFG and the cerebellum, but decreased the BOLD signals in the putamen and the LG. These findings also support the idea that brain function requires additional attention resources under noisier conditions. Load- and acoustic noise-related changes in BOLD responses correlated negatively in the WM network. This study demonstrates that MR noise affects brain activation pattern. Future comparisons between studies performed under different acoustic conditions (due to differing magnetic field strengths, pulse sequences, or scanner manufacturers) might require knowledge of the sound pressure level of acoustic noise during fMRI. PMID:15893942
Portoles, Oscar; Borst, Jelmer P; van Vugt, Marieke K
Numerous studies seek to understand the role of oscillatory synchronization in cognition. This problem is particularly challenging in the context of complex cognitive behavior, which consists of a sequence of processing steps with uncertain duration. In this study, we analyzed oscillatory connectivity measures in time windows that previous computational models had associated with