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Sample records for showed enhanced memory

  1. Adaptive memory: young children show enhanced retention of fitness-related information.

    Science.gov (United States)

    Aslan, Alp; Bäuml, Karl-Heinz T

    2012-01-01

    Evolutionary psychologists propose that human cognition evolved through natural selection to solve adaptive problems related to survival and reproduction, with its ultimate function being the enhancement of reproductive fitness. Following this proposal and the evolutionary-developmental view that ancestral selection pressures operated not only on reproductive adults, but also on pre-reproductive children, the present study examined whether young children show superior memory for information that is processed in terms of its survival value. In two experiments, we found such survival processing to enhance retention in 4- to 10-year-old children, relative to various control conditions that also required deep, meaningful processing but were not related to survival. These results suggest that, already in very young children, survival processing is a special and extraordinarily effective form of memory encoding. The results support the functional-evolutionary proposal that young children's memory is "tuned" to process and retain fitness-related information. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. The development of adaptive memory: Young children show enhanced retention of animacy-related information.

    Science.gov (United States)

    Aslan, Alp; John, Thomas

    2016-12-01

    Previous developmental work has indicated that animacy is a foundational ontogenetic category that is given priority already early in life. Here, we investigated whether such priority is also present in children's episodic memory, examining whether young children show enhanced retention of animacy-related information. Kindergartners and younger and older elementary school children were presented with fictitious (non)words (e.g., BULA, LAFE) paired with properties characteristic of humans (e.g., "likes music"), (nonhuman) animals (e.g., "builds nests"), and inanimate things (e.g., "has four edges") and were asked to rate the animacy status of each nonword. After a retention interval, a surprise recognition test for the nonwords was administered. We found enhanced recognition of nonwords paired with human and animal properties compared with (the same) nonwords paired with inanimate properties. The size of this animacy advantage was comparable across age groups, suggesting developmental invariance of the advantage over the age range examined (i.e., 4-11years). The results support a functional-evolutionary view on memory, suggesting that already young children's memory is "tuned" to process and retain animacy. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Mechanisms of Memory Enhancement

    Science.gov (United States)

    Stern, Sarah A.

    2012-01-01

    The ongoing quest for memory enhancement is one that grows necessary as the global population increasingly ages. The extraordinary progress that has been made in the past few decades elucidating the underlying mechanisms of how long-term memories are formed has provided insight into how memories might also be enhanced. Capitalizing on this knowledge, it has been postulated that targeting many of the same mechanisms, including CREB activation, AMPA/NMDA receptor trafficking, neuromodulation (e.g. via dopamine, adrenaline, cortisol or acetylcholine) and metabolic processes (e.g. via glucose and insulin) may all lead to the enhancement of memory. These and other mechanisms and/or approaches have been tested via genetic or pharmacological methods in animal models, and several have been investigated in humans as well. In addition, a number of behavioral methods, including exercise and reconsolidation, may also serve to strengthen and enhance memories. By capitalizing on this knowledge and continuing to investigate these promising avenues, memory enhancement may indeed be achieved in the future. PMID:23151999

  4. Distributed learning enhances relational memory consolidation.

    Science.gov (United States)

    Litman, Leib; Davachi, Lila

    2008-09-01

    It has long been known that distributed learning (DL) provides a mnemonic advantage over massed learning (ML). However, the underlying mechanisms that drive this robust mnemonic effect remain largely unknown. In two experiments, we show that DL across a 24 hr interval does not enhance immediate memory performance but instead slows the rate of forgetting relative to ML. Furthermore, we demonstrate that this savings in forgetting is specific to relational, but not item, memory. In the context of extant theories and knowledge of memory consolidation, these results suggest that an important mechanism underlying the mnemonic benefit of DL is enhanced memory consolidation. We speculate that synaptic strengthening mechanisms supporting long-term memory consolidation may be differentially mediated by the spacing of memory reactivation. These findings have broad implications for the scientific study of episodic memory consolidation and, more generally, for educational curriculum development and policy.

  5. Phytoceramide Shows Neuroprotection and Ameliorates Scopolamine-Induced Memory Impairment

    Directory of Open Access Journals (Sweden)

    Seikwan Oh

    2011-10-01

    Full Text Available The function and the role phytoceramide (PCER and phytosphingosine (PSO in the central nervous system has not been well studied. This study was aimed at investigating the possible roles of PCER and PSO in glutamate-induced neurotoxicity in cultured neuronal cells and memory function in mice. Phytoceramide showed neuro-protective activity in the glutamate-induced toxicity in cultured cortical neuronal cells. Neither phytosphingosine nor tetraacetylphytosphingosine (TAPS showed neuroproective effects in neuronal cells. PCER (50 mg/kg, p.o. recovered the scopolamine-induced reduction in step-through latency in the passive avoidance test; however, PSO did not modulate memory function on this task. The ameliorating effects of PCER on spatial memory were confirmed by the Morris water maze test. In conclusion, through behavioral and neurochemical experimental results, it was demonstrated that central administration of PCER produces amelioration of memory impairment. These results suggest that PCER plays an important role in neuroprotection and memory enhancement and PCER could be a potential new therapeutic agent for the treatment of neurodegenerative diseases such as Alzheimer’s disease.

  6. Neurostimulation for Memory Enhancement in Epilepsy.

    Science.gov (United States)

    Meisenhelter, Stephen; Jobst, Barbara C

    2018-04-19

    Memory is one of the top concerns of epilepsy patients, but there are no known treatments to directly alleviate the memory deficits associated with epilepsy. Neurostimulation may provide new therapeutic tools to enhance memory in epilepsy patients. Here, we critically review recent investigations of memory enhancement using transcranial electrical stimulation (tES), transcranial magnetic stimulation (TMS), vagus nerve stimulation (VNS), chronic intracranial stimulation, and acute intracranial stimulation. Existing literature suggests that transcranial direct current stimulation (tDCS) produces a small enhancement in memory in neuropsychological patients, but transcranial alternating current stimulation (tACS) and transcranial random noise stimulation (tRNS) have not been found to have an effect on memory. Most studies of transcranial magnetic stimulation (TMS) have found that TMS has no positive effect on memory. Vagus nerve stimulation can acutely enhance memory, while chronic therapy does not appear to alter memory performance. We found that there is the most evidence for significant memory enhancement using intracranial stimulation techniques, especially chronic stimulation of the fornix and task-responsive stimulation of the lateral temporal lobe. Presently, there are no existing therapeutic options for directly treating epilepy-related memory deficits. While neurostimulation technologies for memory enhancement are largely still in the experimental phase, neurostimulation appears promising as a future technique for treating epilepsy-related memory deficits.

  7. Does emotional memory enhancement assist the memory-impaired?

    Directory of Open Access Journals (Sweden)

    Lucas S. Broster

    2012-03-01

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

  8. Enhanced memory architecture for massively parallel vision chip

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    Chen, Zhe; Yang, Jie; Liu, Liyuan; Wu, Nanjian

    2015-04-01

    Local memory architecture plays an important role in high performance massively parallel vision chip. In this paper, we propose an enhanced memory architecture with compact circuit area designed in a full-custom flow. The memory consists of separate master-stage static latches and shared slave-stage dynamic latches. We use split transmission transistors on the input data path to enhance tolerance for charge sharing and to achieve random read/write capabilities. The memory is designed in a 0.18 μm CMOS process. The area overhead of the memory achieves 16.6 μm2/bit. Simulation results show that the maximum operating frequency reaches 410 MHz and the corresponding peak dynamic power consumption for a 64-bit memory unit is 190 μW under 1.8 V supply voltage.

  9. Reward-enhanced memory in younger and older adults.

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    Spaniol, Julia; Schain, Cécile; Bowen, Holly J

    2014-09-01

    We investigated how the anticipation of remote monetary reward modulates intentional episodic memory formation in younger and older adults. On the basis of prior findings of preserved reward-cognition interactions in aging, we predicted that reward anticipation would be associated with enhanced memory in both younger and older adults. On the basis of previous demonstrations of a time-dependent effect of reward anticipation on memory, we expected the memory enhancement to increase with study-test delay. In Experiment 1, younger and older participants encoded a series of picture stimuli associated with high- or low-reward values. At test (24-hr postencoding), recognition hits resulted in either high or low monetary rewards, whereas false alarms were penalized to discourage guessing. Experiment 2 was similar to Experiment 1, but the study-test delay was manipulated within subjects (immediate vs 24hr). In Experiment 1, younger and older adults showed enhanced recognition for high-reward pictures compared with low-reward pictures. Experiment 2 replicated this finding and additionally showed that the effect did not extend to immediate recognition. The current findings provide support for a time-dependent mechanism of reward-based memory enhancement. They also suggest that aging leaves intact the positive influence of reward anticipation on intentional long-term memory formation. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Source memory enhancement for emotional words.

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    Doerksen, S; Shimamura, A P

    2001-03-01

    The influence of emotional stimuli on source memory was investigated by using emotionally valenced words. The words were colored blue or yellow (Experiment 1) or surrounded by a blue or yellow frame (Experiment 2). Participants were asked to associate the words with the colors. In both experiments, emotionally valenced words elicited enhanced free recall compared with nonvalenced words; however, recognition memory was not affected. Source memory for the associated color was also enhanced for emotional words, suggesting that even memory for contextual information is benefited by emotional stimuli. This effect was not due to the ease of semantic clustering of emotional words because semantically related words were not associated with enhanced source memory, despite enhanced recall (Experiment 3). It is suggested that enhancement resulted from facilitated arousal or attention, which may act to increase organization processes important for source memory.

  11. Enhanced Source Memory for Names of Cheaters

    OpenAIRE

    Raoul Bell; Axel Buchner

    2009-01-01

    The present experiment shows that source memory for names associated with a history of cheating is better than source memory for names associated with irrelevant or trustworthy behavior, whereas old-new discrimination is not affected by whether a name was associated with cheating. This data pattern closely replicates findings obtained in previous experiments using facial stimuli, thus demonstrating that enhanced source memory for cheaters is not due to a cheater-detection module closely tied ...

  12. Sleep enhances memory consolidation in children.

    Science.gov (United States)

    Ashworth, Anna; Hill, Catherine M; Karmiloff-Smith, Annette; Dimitriou, Dagmara

    2014-06-01

    Sleep is an active state that plays an important role in the consolidation of memory. It has been found to enhance explicit memories in both adults and children. However, in contrast to adults, children do not always show a sleep-related improvement in implicit learning. The majority of research on sleep-dependent memory consolidation focuses on adults; hence, the current study examined sleep-related effects on two tasks in children. Thirty-three typically developing children aged 6-12 years took part in the study. Actigraphy was used to monitor sleep. Sleep-dependent memory consolidation was assessed using a novel non-word learning task and the Tower of Hanoi cognitive puzzle, which involves discovering an underlying rule to aid completion. Children were trained on the two tasks and retested following approximately equal retention intervals of both wake and sleep. After sleep, children showed significant improvements in performance of 14% on the non-word learning task and 25% on the Tower of Hanoi task, but no significant change in score following the wake retention interval. Improved performance on the Tower of Hanoi may have been due to children consolidating explicit aspects of the task, for example rule-learning or memory of previous sequences; thus, we propose that sleep is necessary for consolidation of explicit memory in children. Sleep quality and duration were not related to children's task performance. If such experimental sleep-related learning enhancement is generalizable to everyday life, then it is clear that sleep plays a vital role in children's educational attainment. © 2013 European Sleep Research Society.

  13. Amygdala activity related to enhanced memory for pleasant and aversive stimuli.

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    Hamann, S B; Ely, T D; Grafton, S T; Kilts, C D

    1999-03-01

    Pleasant or aversive events are better remembered than neutral events. Emotional enhancement of episodic memory has been linked to the amygdala in animal and neuropsychological studies. Using positron emission tomography, we show that bilateral amygdala activity during memory encoding is correlated with enhanced episodic recognition memory for both pleasant and aversive visual stimuli relative to neutral stimuli, and that this relationship is specific to emotional stimuli. Furthermore, data suggest that the amygdala enhances episodic memory in part through modulation of hippocampal activity. The human amygdala seems to modulate the strength of conscious memory for events according to emotional importance, regardless of whether the emotion is pleasant or aversive.

  14. Memory Transformation Enhances Reinforcement Learning in Dynamic Environments.

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    Santoro, Adam; Frankland, Paul W; Richards, Blake A

    2016-11-30

    Over the course of systems consolidation, there is a switch from a reliance on detailed episodic memories to generalized schematic memories. This switch is sometimes referred to as "memory transformation." Here we demonstrate a previously unappreciated benefit of memory transformation, namely, its ability to enhance reinforcement learning in a dynamic environment. We developed a neural network that is trained to find rewards in a foraging task where reward locations are continuously changing. The network can use memories for specific locations (episodic memories) and statistical patterns of locations (schematic memories) to guide its search. We find that switching from an episodic to a schematic strategy over time leads to enhanced performance due to the tendency for the reward location to be highly correlated with itself in the short-term, but regress to a stable distribution in the long-term. We also show that the statistics of the environment determine the optimal utilization of both types of memory. Our work recasts the theoretical question of why memory transformation occurs, shifting the focus from the avoidance of memory interference toward the enhancement of reinforcement learning across multiple timescales. As time passes, memories transform from a highly detailed state to a more gist-like state, in a process called "memory transformation." Theories of memory transformation speak to its advantages in terms of reducing memory interference, increasing memory robustness, and building models of the environment. However, the role of memory transformation from the perspective of an agent that continuously acts and receives reward in its environment is not well explored. In this work, we demonstrate a view of memory transformation that defines it as a way of optimizing behavior across multiple timescales. Copyright © 2016 the authors 0270-6474/16/3612228-15$15.00/0.

  15. Exploring the use of memory colors for image enhancement

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    Xue, Su; Tan, Minghui; McNamara, Ann; Dorsey, Julie; Rushmeier, Holly

    2014-02-01

    Memory colors refer to those colors recalled in association with familiar objects. While some previous work introduces this concept to assist digital image enhancement, their basis, i.e., on-screen memory colors, are not appropriately investigated. In addition, the resulting adjustment methods developed are not evaluated from a perceptual view of point. In this paper, we first perform a context-free perceptual experiment to establish the overall distributions of screen memory colors for three pervasive objects. Then, we use a context-based experiment to locate the most representative memory colors; at the same time, we investigate the interactions of memory colors between different objects. Finally, we show a simple yet effective application using representative memory colors to enhance digital images. A user study is performed to evaluate the performance of our technique.

  16. Mice Overexpressing Type 1 Adenylyl Cyclase Show Enhanced Spatial Memory Flexibility in the Absence of Intact Synaptic Long-Term Depression

    Science.gov (United States)

    Zhang, Ming; Wang, Hongbing

    2013-01-01

    There is significant interest in understanding the contribution of intracellular signaling and synaptic substrates to memory flexibility, which involves new learning and suppression of obsolete memory. Here, we report that enhancement of Ca[superscript 2+]-stimulated cAMP signaling by overexpressing type 1 adenylyl cyclase (AC1) facilitated…

  17. Nicotine enhances the reconsolidation of novel object recognition memory in rats.

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    Tian, Shaowen; Pan, Si; You, Yong

    2015-02-01

    There is increasing evidence that nicotine is involved in learning and memory. However, there are only few studies that have evaluated the relationship between nicotine and memory reconsolidation. In this study, we investigated the effects of nicotine on the reconsolidation of novel object recognition memory in rats. Behavior procedure involved four training phases: habituation (Days 1 and 2), sample (Day 3), reactivation (Day 4) and test (Day 6). Rats were injected with saline or nicotine (0.1, 0.2 and 0.4 mg/kg) immediately or 6h after reactivation. The discrimination index was used to assess memory performance and calculated as the difference in time exploring on the novel and familiar objects. Results showed that nicotine administration immediately but not 6 h after reactivation significantly enhanced memory performance of rats. Further results showed that the enhancing effect of nicotine on memory performance was dependent on memory reactivation, and was not attributed to the changes of the nonspecific responses (locomotor activity and anxiety level) 48 h after nicotine administration. The results suggest that post-reactivation nicotine administration enhances the reconsolidation of novel object recognition memory. Our present finding extends previous research on the nicotinic effects on learning and memory. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. The lasting memory enhancements of retrospective attention

    OpenAIRE

    Reaves, Sarah; Strunk, Jonathan; Phillips, Shekinah; Verhaeghen, Paul; Duarte, Audrey

    2016-01-01

    Behavioral research has shown that spatial cues that orient attention toward task relevant items being maintained in visual short-term memory (VSTM) enhance item memory accuracy. However, it is unknown if these retrospective attentional cues (?retro-cues?) enhance memory beyond typical short-term memory delays. It is also unknown whether retro-cues affect the spatial information associated with VSTM representations. Emerging evidence suggests that processes that affect short-term memory maint...

  19. Enhanced Source Memory for Names of Cheaters

    Directory of Open Access Journals (Sweden)

    Raoul Bell

    2009-04-01

    Full Text Available The present experiment shows that source memory for names associated with a history of cheating is better than source memory for names associated with irrelevant or trustworthy behavior, whereas old-new discrimination is not affected by whether a name was associated with cheating. This data pattern closely replicates findings obtained in previous experiments using facial stimuli, thus demonstrating that enhanced source memory for cheaters is not due to a cheater-detection module closely tied to the face processing system, but is rather due to a more general bias towards remembering the source of information associated with cheating.

  20. Social importance enhances prospective memory: evidence from an event-based task.

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    Walter, Stefan; Meier, Beat

    2017-07-01

    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.

  1. Emotional Arousal Does Not Enhance Association-Memory

    Science.gov (United States)

    Madan, Christopher R.; Caplan, Jeremy B.; Lau, Christine S. M.; Fujiwara, Esther

    2012-01-01

    Emotionally arousing information is remembered better than neutral information. This enhancement effect has been shown for memory for items. In contrast, studies of association-memory have found both impairments and enhancements of association-memory by arousal. We aimed to resolve these conflicting results by using a cued-recall paradigm combined…

  2. Enhancement of Immune Memory Responses to Respiratory Infection

    Science.gov (United States)

    2017-08-01

    AWARD NUMBER: W81XWH-16-1-0360 TITLE: Enhancement of Immune Memory Responses to Respiratory Infection PRINCIPAL INVESTIGATORs: Dr Min Chen PhD...5a. CONTRACT NUMBER Enhancement of Immune Memory Responses to Respiratory Infection 5b. GRANT NUMBER W81XWH-16-1-0360 5c. PROGRAM ELEMENT NUMBER...entitled “ENHANCEMENT OF IMMUNE MEMORY RESPONSES TO RESPIRATORY INFECTION: AUTOPHAGY IN MEMORY B-CELLS RESPONSE TO INFLUENZA VACCINE (AMBRIV

  3. Post-encoding emotional arousal enhances consolidation of item memory, but not reality-monitoring source memory.

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    Wang, Bo; Sun, Bukuan

    2017-03-01

    The current study examined whether the effect of post-encoding emotional arousal on item memory extends to reality-monitoring source memory and, if so, whether the effect depends on emotionality of learning stimuli and testing format. In Experiment 1, participants encoded neutral words and imagined or viewed their corresponding object pictures. Then they watched a neutral, positive, or negative video. The 24-hour delayed test showed that emotional arousal had little effect on both item memory and reality-monitoring source memory. Experiment 2 was similar except that participants encoded neutral, positive, and negative words and imagined or viewed their corresponding object pictures. The results showed that positive and negative emotional arousal induced after encoding enhanced consolidation of item memory, but not reality-monitoring source memory, regardless of emotionality of learning stimuli. Experiment 3, identical to Experiment 2 except that participants were tested only on source memory for all the encoded items, still showed that post-encoding emotional arousal had little effect on consolidation of reality-monitoring source memory. Taken together, regardless of emotionality of learning stimuli and regardless of testing format of source memory (conjunction test vs. independent test), the facilitatory effect of post-encoding emotional arousal on item memory does not generalize to reality-monitoring source memory.

  4. Enhanced recognition memory in grapheme-color synaesthesia for different categories of visual stimuli.

    Science.gov (United States)

    Ward, Jamie; Hovard, Peter; Jones, Alicia; Rothen, Nicolas

    2013-01-01

    Memory has been shown to be enhanced in grapheme-color synaesthesia, and this enhancement extends to certain visual stimuli (that don't induce synaesthesia) as well as stimuli comprised of graphemes (which do). Previous studies have used a variety of testing procedures to assess memory in synaesthesia (e.g., free recall, recognition, associative learning) making it hard to know the extent to which memory benefits are attributable to the stimulus properties themselves, the testing method, participant strategies, or some combination of these factors. In the first experiment, we use the same testing procedure (recognition memory) for a variety of stimuli (written words, non-words, scenes, and fractals) and also check which memorization strategies were used. We demonstrate that grapheme-color synaesthetes show enhanced memory across all these stimuli, but this is not found for a non-visual type of synaesthesia (lexical-gustatory). In the second experiment, the memory advantage for scenes is explored further by manipulating the properties of the old and new images (changing color, orientation, or object presence). Again, grapheme-color synaesthetes show a memory advantage for scenes across all manipulations. Although recognition memory is generally enhanced in this study, the largest effects were found for abstract visual images (fractals) and scenes for which color can be used to discriminate old/new status.

  5. A novel whole-cell mechanism for long-term memory enhancement.

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    Iris Reuveni

    Full Text Available Olfactory-discrimination learning was shown to induce a profound long-lasting enhancement in the strength of excitatory and inhibitory synapses of pyramidal neurons in the piriform cortex. Notably, such enhancement was mostly pronounced in a sub-group of neurons, entailing about a quarter of the cell population. Here we first show that the prominent enhancement in the subset of cells is due to a process in which all excitatory synapses doubled their strength and that this increase was mediated by a single process in which the AMPA channel conductance was doubled. Moreover, using a neuronal-network model, we show how such a multiplicative whole-cell synaptic strengthening in a sub-group of cells that form a memory pattern, sub-serves a profound selective enhancement of this memory. Network modeling further predicts that synaptic inhibition should be modified by complex learning in a manner that much resembles synaptic excitation. Indeed, in a subset of neurons all GABAA-receptors mediated inhibitory synapses also doubled their strength after learning. Like synaptic excitation, Synaptic inhibition is also enhanced by two-fold increase of the single channel conductance. These findings suggest that crucial learning induces a multiplicative increase in strength of all excitatory and inhibitory synapses in a subset of cells, and that such an increase can serve as a long-term whole-cell mechanism to profoundly enhance an existing Hebbian-type memory. This mechanism does not act as synaptic plasticity mechanism that underlies memory formation but rather enhances the response of already existing memory. This mechanism is cell-specific rather than synapse-specific; it modifies the channel conductance rather than the number of channels and thus has the potential to be readily induced and un-induced by whole-cell transduction mechanisms.

  6. Sleep enhances false memories depending on general memory performance.

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    Diekelmann, Susanne; Born, Jan; Wagner, Ullrich

    2010-04-02

    Memory is subject to dynamic changes, sometimes giving rise to the formation of false memories due to biased processes of consolidation or retrieval. Sleep is known to benefit memory consolidation through an active reorganization of representations whereas acute sleep deprivation impairs retrieval functions. Here, we investigated whether sleep after learning and sleep deprivation at retrieval enhance the generation of false memories in a free recall test. According to the Deese, Roediger, McDermott (DRM) false memory paradigm, subjects learned lists of semantically associated words (e.g., "night", "dark", "coal", etc.), lacking the strongest common associate or theme word (here: "black"). Free recall was tested after 9h following a night of sleep, a night of wakefulness (sleep deprivation) or daytime wakefulness. Compared with memory performance after a retention period of daytime wakefulness, both post-learning nocturnal sleep as well as acute sleep deprivation at retrieval significantly enhanced false recall of theme words. However, these effects were only observed in subjects with low general memory performance. These data point to two different ways in which sleep affects false memory generation through semantic generalization: one acts during consolidation on the memory trace per se, presumably by active reorganization of the trace in the post-learning sleep period. The other is related to the recovery function of sleep and affects cognitive control processes of retrieval. Both effects are unmasked when the material is relatively weakly encoded. Crown Copyright 2009. Published by Elsevier B.V. All rights reserved.

  7. Enhanced Recognition Memory in Grapheme-Colour Synaesthesia for Different Categories of Visual Stimuli

    Directory of Open Access Journals (Sweden)

    Jamie eWard

    2013-10-01

    Full Text Available Memory has been shown to be enhanced in grapheme-colour synaesthesia, and this enhancement extends to certain visual stimuli (that don’t induce synaesthesia as well as stimuli comprised of graphemes (which do. Previous studies have used a variety of testing procedures to assess memory in synaesthesia (e.g. free recall, recognition, associative learning making it hard to know the extent to which memory benefits are attributable to the stimulus properties themselves, the testing method, participant strategies, or some combination of these factors. In the first experiment, we use the same testing procedure (recognition memory for a variety of stimuli (written words, nonwords, scenes, and fractals and also check which memorisation strategies were used. We demonstrate that grapheme-colour synaesthetes show enhanced memory across all these stimuli, but this is not found for a non-visual type of synaesthesia (lexical-gustatory. In the second experiment, the memory advantage for scenes is explored further by manipulating the properties of the old and new images (changing colour, orientation, or object presence. Again, grapheme-colour synaesthetes show a memory advantage for scenes across all manipulations. Although recognition memory is generally enhanced in this study, the largest effects were found for abstract visual images (fractals and scenes for which colour can be used to discriminate old/new status.

  8. Self-imagining enhances recognition memory in memory-impaired individuals with neurological damage.

    Science.gov (United States)

    Grilli, Matthew D; Glisky, Elizabeth L

    2010-11-01

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

  9. Working memory-driven attention improves spatial resolution: Support for perceptual enhancement.

    Science.gov (United States)

    Pan, Yi; Luo, Qianying; Cheng, Min

    2016-08-01

    Previous research has indicated that attention can be biased toward those stimuli matching the contents of working memory and thereby facilitates visual processing at the location of the memory-matching stimuli. However, whether this working memory-driven attentional modulation takes place on early perceptual processes remains unclear. Our present results showed that working memory-driven attention improved identification of a brief Landolt target presented alone in the visual field. Because the suprathreshold target appeared without any external noise added (i.e., no distractors or masks), the results suggest that working memory-driven attention enhances the target signal at early perceptual stages of visual processing. Furthermore, given that performance in the Landolt target identification task indexes spatial resolution, this attentional facilitation indicates that working memory-driven attention can boost early perceptual processing via enhancement of spatial resolution at the attended location.

  10. Social relevance enhances memory for impressions in older adults.

    Science.gov (United States)

    Cassidy, Brittany S; Gutchess, Angela H

    2012-01-01

    Previous research has demonstrated that older adults have difficulty retrieving contextual material over items alone. Recent research suggests this deficit can be reduced by adding emotional context, allowing for the possibility that memory for social impressions may show less age-related decline than memory for other types of contextual information. Two studies investigated how orienting to social or self-relevant aspects of information contributed to the learning and retrieval of impressions in young and older adults. Participants encoded impressions of others in conditions varying in the use of self-reference (Experiment 1) and interpersonal meaningfulness (Experiment 2), and completed memory tasks requiring the retrieval of specific traits. For both experiments, age groups remembered similar numbers of impressions. In Experiment 1 using more self-relevant encoding contexts increased memory for impressions over orienting to stimuli in a non-social way, regardless of age. In Experiment 2 older adults had enhanced memory for impressions presented in an interpersonally meaningful relative to a personally irrelevant way, whereas young adults were unaffected by this manipulation. The results provide evidence that increasing social relevance ameliorates age differences in memory for impressions, and enhances older adults' ability to successfully retrieve contextual information.

  11. Memory enhancement by Tamoxifen on amyloidosis mouse model.

    Science.gov (United States)

    Pandey, Deepika; Banerjee, Sugato; Basu, Mahua; Mishra, Nibha

    2016-03-01

    Tamoxifen (TMX) is a selective estrogen receptor modulator (SERM) used in the treatment of breast cancer. Earlier studies show its neuroprotection via regulating apoptosis, microglial functions, and synaptic plasticity. TMX also showed memory enhancement in ovariectomized mice, and protection from amyloid induced damage in hippocampal cell line. These reports encouraged us to explore the role of TMX in relevance to Alzheimer's disease (AD). We report here, the effect of TMX treatment a) on memory, and b) levels of neurotransmitters (acetylcholine (ACh) and dopamine (DA)) in breeding-retired-female mice injected with beta amyloid1-42 (Aβ1-42). Mice were treated with TMX (10mg/kg, i.p.) for 15 days. In Morris water maze test, the TMX treated mice escape latency decreased during training trials. They also spent longer time in the platform quadrant on probe trial, compared to controls. In Passive avoidance test, TMX treated mice avoided stepping on the shock chamber. This suggests that TMX protects memory from Aβ induced toxicity. In frontal cortex, ACh was moderately increased, with TMX treatment. In striatum, dopamine was significantly increased, 3,4-dihydroxyphenylacetic acid (DOPAC) level and DOPAC/DA ratio was decreased post TMX treatment. Therefore, TMX enhances spatial and contextual memory by reducing dopamine metabolism and increasing ACh level in Aβ1-42 injected-breeding-retired-female mice. Copyright © 2015. Published by Elsevier Inc.

  12. Reward-Enhanced Memory in Younger and Older Adults

    OpenAIRE

    Julia Spaniol; Cécile Schain; Holly J. Bowen

    2014-01-01

    Objectives. We investigated how the anticipation of remote monetary reward modulates intentional episodic memory formation in younger and older adults. On the basis of prior findings of preserved reward–cognition interactions in aging, we predicted that reward anticipation would be associated with enhanced memory in both younger and older adults. On the basis of previous demonstrations of a time-dependent effect of reward anticipation on memory, we expected the memory enhancement to increase ...

  13. Reward retroactively enhances memory consolidation for related items

    OpenAIRE

    Patil, Anuya; Murty, Vishnu P.; Dunsmoor, Joseph E.; Phelps, Elizabeth A.; Davachi, Lila

    2017-01-01

    Reward motivation has been shown to modulate episodic memory processes in order to support future adaptive behavior. However, for a memory system to be truly adaptive, it should enhance memory for rewarded events as well as for neutral events that may seem inconsequential at the time of encoding but can gain importance later. Here, we investigated the influence of reward motivation on retroactive memory enhancement selectively for conceptually related information. We found behavioral evidence...

  14. An Easy Way to Show Memory Color Effects.

    Science.gov (United States)

    Witzel, Christoph

    2016-01-01

    This study proposes and evaluates a simple stimulus display that allows one to measure memory color effects (the effect of object knowledge and memory on color perception). The proposed approach is fast and easy and does not require running an extensive experiment. It shows that memory color effects are robust to minor variations due to a lack of color calibration.

  15. An Easy Way to Show Memory Color Effects

    OpenAIRE

    Witzel, Christoph

    2016-01-01

    This study proposes and evaluates a simple stimulus display that allows one to measure memory color effects (the effect of object knowledge and memory on color perception). The proposed approach is fast and easy and does not require running an extensive experiment. It shows that memory color effects are robust to minor variations due to a lack of color calibration.

  16. The lasting memory enhancements of retrospective attention.

    Science.gov (United States)

    Reaves, Sarah; Strunk, Jonathan; Phillips, Shekinah; Verhaeghen, Paul; Duarte, Audrey

    2016-07-01

    Behavioral research has shown that spatial cues that orient attention toward task relevant items being maintained in visual short-term memory (VSTM) enhance item memory accuracy. However, it is unknown if these retrospective attentional cues ("retro-cues") enhance memory beyond typical short-term memory delays. It is also unknown whether retro-cues affect the spatial information associated with VSTM representations. Emerging evidence suggests that processes that affect short-term memory maintenance may also affect long-term memory (LTM) but little work has investigated the role of attention in LTM. In the current event-related potential (ERP) study, we investigated the duration of retrospective attention effects and the impact of retrospective attention manipulations on VSTM representations. Results revealed that retro-cueing improved both VSTM and LTM memory accuracy and that posterior maximal ERPs observed during VSTM maintenance predicted subsequent LTM performance. N2pc ERPs associated with attentional selection were attenuated by retro-cueing suggesting that retrospective attention may disrupt maintenance of spatial configural information in VSTM. Collectively, these findings suggest that retrospective attention can alter the structure of memory representations, which impacts memory performance beyond short-term memory delays. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. The lasting memory enhancements of retrospective attention

    Science.gov (United States)

    Reaves, Sarah; Strunk, Jonathan; Phillips, Shekinah; Verhaeghen, Paul; Duarte, Audrey

    2016-01-01

    Behavioral research has shown that spatial cues that orient attention toward task relevant items being maintained in visual short-term memory (VSTM) enhance item memory accuracy. However, it is unknown if these retrospective attentional cues (“retro-cues”) enhance memory beyond typical short-term memory delays. It is also unknown whether retro-cues affect the spatial information associated with VSTM representations. Emerging evidence suggests that processes that affect short-term memory maintenance may also affect long-term memory (LTM) but little work has investigated the role of attention in LTM. In the current event-related potential (ERP) study, we investigated the duration of retrospective attention effects and the impact of retrospective attention manipulations on VSTM representations. Results revealed that retro-cueing improved both VSTM and LTM memory accuracy and that posterior maximal ERPs observed during VSTM maintenance predicted subsequent LTM performance. N2pc ERPs associated with attentional selection were attenuated by retro-cueing suggesting that retrospective attention may disrupt maintenance of spatial configural information in VSTM. Collectively, these findings suggest that retrospective attention can alter the structure of memory representations, which impacts memory performance beyond short-term memory delays. PMID:27038756

  18. Sleep Enhances Explicit Recollection in Recognition Memory

    Science.gov (United States)

    Drosopoulos, Spyridon; Wagner, Ullrich; Born, Jan

    2005-01-01

    Recognition memory is considered to be supported by two different memory processes, i.e., the explicit recollection of information about a previous event and an implicit process of recognition based on a contextual sense of familiarity. Both types of memory supposedly rely on distinct memory systems. Sleep is known to enhance the consolidation of…

  19. Procedure Of Teaching Grammar Using Memory Enhancement

    Directory of Open Access Journals (Sweden)

    Herri Susanto

    2011-11-01

    Full Text Available Teaching grammar has been regarded as a process of understanding from the context. It means a teacher teaches the pupils contextually more than just the rules. However, I have my own experience that teaching grammar methods must depend on the purposes of learning grammar. Some people learn grammar as a means to fulfill the syllabus needs for schools but other people learn grammar for special purposes out of school syllabus, such as for entrance test. For these reasons, the methods of teaching grammar should be different. The students who learn grammar based on the school syllabus probably needs longer procedure of learning that usually uses contextual teaching through listening, speaking, writing, and reading. Nevertheless, students who learn grammar for test need shorter procedure of learning such as memorizing. Therefore, I propose giving a workshop of teaching grammar using memory enhancement as another alternative teaching grammar method. This workshop would show the class that grammar can be learnt through memory enhancement process, i.e.; mind map, music, memory technique and drill to boost up students understanding for test preparation.

  20. Optogenetic Stimulation of Prefrontal Glutamatergic Neurons Enhances Recognition Memory.

    Science.gov (United States)

    Benn, Abigail; Barker, Gareth R I; Stuart, Sarah A; Roloff, Eva V L; Teschemacher, Anja G; Warburton, E Clea; Robinson, Emma S J

    2016-05-04

    Finding effective cognitive enhancers is a major health challenge; however, modulating glutamatergic neurotransmission has the potential to enhance performance in recognition memory tasks. Previous studies using glutamate receptor antagonists have revealed that the medial prefrontal cortex (mPFC) plays a central role in associative recognition memory. The present study investigates short-term recognition memory using optogenetics to target glutamatergic neurons within the rodent mPFC specifically. Selective stimulation of glutamatergic neurons during the online maintenance of information enhanced associative recognition memory in normal animals. This cognitive enhancing effect was replicated by local infusions of the AMPAkine CX516, but not CX546, which differ in their effects on EPSPs. This suggests that enhancing the amplitude, but not the duration, of excitatory synaptic currents improves memory performance. Increasing glutamate release through infusions of the mGluR7 presynaptic receptor antagonist MMPIP had no effect on performance. These results provide new mechanistic information that could guide the targeting of future cognitive enhancers. Our work suggests that improved associative-recognition memory can be achieved by enhancing endogenous glutamatergic neuronal activity selectively using an optogenetic approach. We build on these observations to recapitulate this effect using drug treatments that enhance the amplitude of EPSPs; however, drugs that alter the duration of the EPSP or increase glutamate release lack efficacy. This suggests that both neural and temporal specificity are needed to achieve cognitive enhancement. Copyright © 2016 Benn et al.

  1. Antidepressant drugs specifically inhibiting noradrenaline reuptake enhance recognition memory in rats.

    Science.gov (United States)

    Feltmann, Kristin; Konradsson-Geuken, Åsa; De Bundel, Dimitri; Lindskog, Maria; Schilström, Björn

    2015-12-01

    Patients suffering from major depression often experience memory deficits even after the remission of mood symptoms, and many antidepressant drugs do not affect, or impair, memory in animals and humans. However, some antidepressant drugs, after a single dose, enhance cognition in humans (Harmer et al., 2009). To compare different classes of antidepressant drugs for their potential as memory enhancers, we used a version of the novel object recognition task in which rats spontaneously forget objects 24 hr after their presentation. Antidepressant drugs were injected systemically 30 min before or directly after the training phase (Session 1 [S1]). Post-S1 injections were used to test for specific memory-consolidation effects. The noradrenaline reuptake inhibitors reboxetine and atomoxetine, as well as the serotonin noradrenaline reuptake inhibitor duloxetine, injected prior to S1 significantly enhanced recognition memory. In contrast, the serotonin reuptake inhibitors citalopram and paroxetine and the cyclic antidepressant drugs desipramine and mianserin did not enhance recognition memory. Post-S1 injection of either reboxetine or citalopram significantly enhanced recognition memory, indicating an effect on memory consolidation. The fact that citalopram had an effect only when injected after S1 suggests that it may counteract its own consolidation-enhancing effect by interfering with memory acquisition. However, pretreatment with citalopram did not attenuate reboxetine's memory-enhancing effect. The D1/5-receptor antagonist SCH23390 blunted reboxetine's memory-enhancing effect, indicating a role of dopaminergic transmission in reboxetine-induced recognition memory enhancement. Our results suggest that antidepressant drugs specifically inhibiting noradrenaline reuptake enhance cognition and may be beneficial in the treatment of cognitive symptoms of depression. (c) 2015 APA, all rights reserved).

  2. Strategies To Enhance Memory Based on Brain-Research.

    Science.gov (United States)

    Banikowski, Alison K.; Mehring, Teresa A.

    1999-01-01

    This article reviews the literature on three aspects of memory: (1) an information processing model of memory (including the sensory register, attention, short-term memory, and long-term memory); (2) instructional strategies designed to enhance memory (which stress gaining students' attention and active involvement); and (3) reasons why…

  3. Can Survival Processing Enhance Story Memory? Testing the Generalizability of the Adaptive Memory Framework

    Science.gov (United States)

    Seamon, John G.; Bohn, Justin M.; Coddington, Inslee E.; Ebling, Maritza C.; Grund, Ethan M.; Haring, Catherine T.; Jang, Sue-Jung; Kim, Daniel; Liong, Christopher; Paley, Frances M.; Pang, Luke K.; Siddique, Ashik H.

    2012-01-01

    Research from the adaptive memory framework shows that thinking about words in terms of their survival value in an incidental learning task enhances their free recall relative to other semantic encoding strategies and intentional learning (Nairne, Pandeirada, & Thompson, 2008). We found similar results. When participants used incidental…

  4. Random walk with memory enhancement and decay

    Science.gov (United States)

    Tan, Zhi-Jie; Zou, Xian-Wu; Huang, Sheng-You; Zhang, Wei; Jin, Zhun-Zhi

    2002-04-01

    A model of random walk with memory enhancement and decay was presented on the basis of the characteristics of the biological intelligent walks. In this model, the movement of the walker is determined by the difference between the remaining information at the jumping-out site and jumping-in site. The amount of the memory information si(t) at a site i is enhanced with the increment of visiting times to that site, and decays with time t by the rate e-βt, where β is the memory decay exponent. When β=0, there exists a transition from Brownian motion (BM) to the compact growth of walking trajectory with the density of information energy u increasing. But for β>0, this transition does not appear and the walk with memory enhancement and decay can be considered as the BM of the mass center of the cluster composed of remembered sites in the late stage.

  5. Post-study caffeine administration enhances memory consolidation in humans.

    Science.gov (United States)

    Borota, Daniel; Murray, Elizabeth; Keceli, Gizem; Chang, Allen; Watabe, Joseph M; Ly, Maria; Toscano, John P; Yassa, Michael A

    2014-02-01

    It is currently not known whether caffeine has an enhancing effect on long-term memory in humans. We used post-study caffeine administration to test its effect on memory consolidation using a behavioral discrimination task. Caffeine enhanced performance 24 h after administration according to an inverted U-shaped dose-response curve; this effect was specific to consolidation and not retrieval. We conclude that caffeine enhanced consolidation of long-term memories in humans.

  6. Memory Enhancement by Targeting Cdk5 Regulation of NR2B

    Science.gov (United States)

    Plattner, Florian; Hernandéz, Adan; Kistler, Tara M.; Pozo, Karine; Zhong, Ping; Yuen, Eunice Y.; Tan, Chunfeng; Hawasli, Ammar H.; Cooke, Sam F.; Nishi, Akinori; Guo, Ailan; Wiederhold, Thorsten; Yan, Zhen; Bibb, James A.

    2014-01-01

    SUMMARY Many psychiatric and neurological disorders are characterized by learning and memory deficits, for which cognitive enhancement is considered a valid treatment strategy. The N-methyl-D-aspartate receptor (NMDAR) is a prime target for the development of cognitive enhancers due to its fundamental role in learning and memory. In particular, the NMDAR subunit NR2B improves synaptic plasticity and memory when over-expressed in neurons. However, NR2B regulation is not well understood and no therapies potentiating NMDAR function have been developed. Here, we show that serine 1116 of NR2B is phosphorylated by cyclin-dependent kinase 5 (Cdk5). Cdk5-dependent NR2B phosphorylation is regulated by neuronal activity and controls the receptor’s cell surface expression. Disrupting NR2B-Cdk5 interaction using a small interfering peptide (siP) increases NR2B surface levels, facilitates synaptic transmission, and improves memory formation in vivo. Our results reveal a novel regulatory mechanism critical to NR2B function that can be targeted for the development of cognitive enhancers. PMID:24607229

  7. Context odor presentation during sleep enhances memory in honeybees.

    Science.gov (United States)

    Zwaka, Hanna; Bartels, Ruth; Gora, Jacob; Franck, Vivien; Culo, Ana; Götsch, Moritz; Menzel, Randolf

    2015-11-02

    Sleep plays an important role in stabilizing new memory traces after learning [1-3]. Here we investigate whether sleep's role in memory processing is similar in evolutionarily distant species and demonstrate that a context trigger during deep-sleep phases improves memory in invertebrates, as it does in humans. We show that in honeybees (Apis mellifera), exposure to an odor during deep sleep that has been present during learning improves memory performance the following day. Presentation of the context odor during wake phases or novel odors during sleep does not enhance memory. In humans, memory consolidation can be triggered by presentation of a context odor during slow-wave sleep that had been present during learning [3-5]. Our results reveal that deep-sleep phases in honeybees have the potential to prompt memory consolidation, just as they do in humans. This study provides strong evidence for a conserved role of sleep-and how it affects memory processes-from insects to mammals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Working memory can enhance unconscious visual perception.

    Science.gov (United States)

    Pan, Yi; Cheng, Qiu-Ping; Luo, Qian-Ying

    2012-06-01

    We demonstrate that unconscious processing of a stimulus property can be enhanced when there is a match between the contents of working memory and the stimulus presented in the visual field. Participants first held a cue (a colored circle) in working memory and then searched for a brief masked target shape presented simultaneously with a distractor shape. When participants reported having no awareness of the target shape at all, search performance was more accurate in the valid condition, where the target matched the cue in color, than in the neutral condition, where the target mismatched the cue. This effect cannot be attributed to bottom-up perceptual priming from the presentation of a memory cue, because unconscious perception was not enhanced when the cue was merely perceptually identified but not actively held in working memory. These findings suggest that reentrant feedback from the contents of working memory modulates unconscious visual perception.

  9. Glucose enhancement of memory depends on initial thirst.

    Science.gov (United States)

    Scholey, Andrew B; Sünram-Lea, Sandra I; Greer, Joanna; Elliott, Jade; Kennedy, David O

    2009-12-01

    This double-blind, placebo-controlled study examined the influence of appetitive state on glucose enhancement of memory. Participants rated their mood, hunger and thirst, then consumed a 25 g glucose drink or a matched placebo 20 min prior to a verbal memory task. There was a double dissociation when the effects of thirst ratings and drink on subsequent memory performance were considered. Those who were initially less thirsty recalled significantly more words following glucose than placebo; those who were more thirsty recalled significantly fewer words after glucose than placebo. Glucose enhancement of memory may therefore critically depend on participants' initial thirst.

  10. Portable wireless neurofeedback system of EEG alpha rhythm enhances memory.

    Science.gov (United States)

    Wei, Ting-Ying; Chang, Da-Wei; Liu, You-De; Liu, Chen-Wei; Young, Chung-Ping; Liang, Sheng-Fu; Shaw, Fu-Zen

    2017-11-13

    Effect of neurofeedback training (NFT) on enhancement of cognitive function or amelioration of clinical symptoms is inconclusive. The trainability of brain rhythm using a neurofeedback system is uncertainty because various experimental designs are used in previous studies. The current study aimed to develop a portable wireless NFT system for alpha rhythm and to validate effect of the NFT system on memory with a sham-controlled group. The proposed system contained an EEG signal analysis device and a smartphone with wireless Bluetooth low-energy technology. Instantaneous 1-s EEG power and contiguous 5-min EEG power throughout the training were developed as feedback information. The training performance and its progression were kept to boost usability of our device. Participants were blinded and randomly assigned into either the control group receiving random 4-Hz power or Alpha group receiving 8-12-Hz power. Working memory and episodic memory were assessed by the backward digital span task and word-pair task, respectively. The portable neurofeedback system had advantages of a tiny size and long-term recording and demonstrated trainability of alpha rhythm in terms of significant increase of power and duration of 8-12 Hz. Moreover, accuracies of the backward digital span task and word-pair task showed significant enhancement in the Alpha group after training compared to the control group. Our tiny portable device demonstrated success trainability of alpha rhythm and enhanced two kinds of memories. The present study suggest that the portable neurofeedback system provides an alternative intervention for memory enhancement.

  11. Memory for time and place contributes to enhanced confidence in memories for emotional events

    Science.gov (United States)

    Rimmele, Ulrike; Davachi, Lila; Phelps, Elizabeth A.

    2012-01-01

    Emotion strengthens the subjective sense of remembering. However, these confidently remembered emotional memories have not been found be more accurate for some types of contextual details. We investigated whether the subjective sense of recollecting negative stimuli is coupled with enhanced memory accuracy for three specific types of central contextual details using the remember/know paradigm and confidence ratings. Our results indicate that the subjective sense of remembering is indeed coupled with better recollection of spatial location and temporal context. In contrast, we found a double-dissociation between the subjective sense of remembering and memory accuracy for colored dots placed in the conceptual center of negative and neutral scenes. These findings show that the enhanced subjective recollective experience for negative stimuli reliably indicates objective recollection for spatial location and temporal context, but not for other types of details, whereas for neutral stimuli, the subjective sense of remembering is coupled with all the types of details assessed. Translating this finding to flashbulb memories, we found that, over time, more participants correctly remembered the location where they learned about the terrorist attacks on 9/11 than any other canonical feature. Likewise participants’ confidence was higher in their memory for location vs. other canonical features. These findings indicate that the strong recollective experience of a negative event corresponds to an accurate memory for some kinds of contextual details, but not other kinds. This discrepancy provides further evidence that the subjective sense of remembering negative events is driven by a different mechanism than the subjective sense of remembering neutral events. PMID:22642353

  12. Memory enhancing drugs and Alzheimer's disease: enhancing the self or preventing the loss of it?

    NARCIS (Netherlands)

    Dekkers, W.J.M.; Olde Rikkert, M.G.M.

    2007-01-01

    In this paper we analyse some ethical and philosophical questions related to the development of memory enhancing drugs (MEDs) and anti-dementia drugs. The world of memory enhancement is coloured by utopian thinking and by the desire for quicker, sharper, and more reliable memories. Dementia is

  13. A flavonol present in cocoa [(-)epicatechin] enhances snail memory.

    Science.gov (United States)

    Fruson, Lee; Dalesman, Sarah; Lukowiak, Ken

    2012-10-15

    Dietary consumption of flavonoids (plant phytochemicals) may improve memory and neuro-cognitive performance, though the mechanism is poorly understood. Previous work has assessed cognitive effects in vertebrates; here we assess the suitability of Lymnaea stagnalis as an invertebrate model to elucidate the effects of flavonoids on cognition. (-)Epicatechin (epi) is a flavonoid present in cocoa, green tea and red wine. We studied its effects on basic snail behaviours (aerial respiration and locomotion), long-term memory (LTM) formation and memory extinction of operantly conditioned aerial respiratory behaviour. We found no significant effect of epi exposure (15 mg l(-1)) on either locomotion or aerial respiration. However, when snails were operantly conditioned in epi for a single 0.5 h training session, which typically results in memory lasting ~3 h, they formed LTM lasting at least 24 h. Snails exposed to epi also showed significantly increased resistance to extinction, consistent with the hypothesis that epi induces a more persistent LTM. Thus training in epi facilitates LTM formation and results in a more persistent and stronger memory. Previous work has indicated that memory-enhancing stressors (predator kairomones and KCl) act via sensory input from the osphradium and are dependent on a serotonergic (5-HT) signalling pathway. Here we found that the effects of epi on LTM were independent of osphradial input and 5-HT, demonstrating that an alternative mechanism of memory enhancement exists in L. stagnalis. Our data are consistent with the notion that dietary sources of epi can improve cognitive abilities, and that L. stagnalis is a suitable model with which to elucidate neuronal mechanisms.

  14. Emotionally negative pictures enhance gist memory.

    Science.gov (United States)

    Bookbinder, S H; Brainerd, C J

    2017-02-01

    In prior work on how true and false memory are influenced by emotion, valence and arousal have often been conflated. Thus, it is difficult to say which specific effects are caused by valence and which are caused by arousal. In the present research, we used a picture-memory paradigm that allowed emotional valence to be manipulated with arousal held constant. Negatively valenced pictures elevated both true and false memory, relative to positive and neutral pictures. Conjoint recognition modeling revealed that negative valence (a) reduced erroneous suppression of true memories and (b) increased the familiarity of the semantic content of both true and false memories. Overall, negative valence impaired the verbatim side of episodic memory but enhanced the gist side, and these effects persisted even after a week-long delay. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. Mindfulness Enhances Episodic Memory Performance: Evidence from a Multimethod Investigation.

    Science.gov (United States)

    Brown, Kirk Warren; Goodman, Robert J; Ryan, Richard M; Anālayo, Bhikkhu

    2016-01-01

    Training in mindfulness, classically described as a receptive attentiveness to present events and experiences, has been shown to improve attention and working memory. Both are key to long-term memory formation, and the present three-study series used multiple methods to examine whether mindfulness would enhance episodic memory, a key form of long-term memory. In Study 1 (N = 143), a self-reported state of mindful attention predicted better recognition performance in the Remember-Know (R-K) paradigm. In Study 2 (N = 93), very brief training in a focused attention form of mindfulness also produced better recognition memory performance on the R-K task relative to a randomized, well-matched active control condition. Study 3 (N = 57) extended these findings by showing that relative to randomized active and inactive control conditions the effect of very brief mindfulness training generalized to free-recall memory performance. This study also found evidence for mediation of the mindfulness training-episodic memory relation by intrinsic motivation. These findings indicate that mindful attention can beneficially impact motivation and episodic memory, with potential implications for educational and occupational performance.

  16. Enhancement of Immune Memory Responses to Respiratory Infection

    Science.gov (United States)

    2017-08-01

    Unlimited Distribution 13. SUPPLEMENTARY NOTES 14. ABSTRACT Maintenance of long - term immunological memory against pathogens is crucial for the rapid...highly expressed in memory B cells in mice, and Atg7 is required for maintenance of long - term memory B cells needed to protect against influenza...AWARD NUMBER: W81XWH-16-1-0361 TITLE: Enhancement of Immune Memory Responses to Respiratory Infection PRINCIPAL INVESTIGATORs: Dr Farrah

  17. Cholecystokinin enhances visceral pain-related affective memory via vagal afferent pathway in rats

    Directory of Open Access Journals (Sweden)

    Cao Bing

    2012-06-01

    Full Text Available Abstract Background Pain contains both sensory and affective dimensions. Using a rodent visceral pain assay that combines the colorectal distension (CRD model with the conditioned place avoidance (CPA paradigms, we measured a learned behavior that directly reflects the affective component of visceral pain, and showed that perigenual anterior cingulate cortex (pACC activation is critical for memory processing involved in long-term visceral affective state and prediction of aversive stimuli by contextual cue. Progress has been made and suggested that activation of vagal afferents plays a role in the behavioral control nociception and memory storage processes. In human patients, electrical vagus nerve stimulation enhanced retention of verbal learning performance. Cholecystokinin-octapeptide (CCK, which is a gastrointestinal hormone released during feeding, has been shown to enhance memory retention. Mice access to food immediately after training session enhanced memory retention. It has been well demonstrated that CCK acting on vagal afferent fibers mediates various physiological functions. We hypothesize that CCK activation of vagal afferent enhances visceral pain-related affective memory. Results In the presented study, infusion of CCK-8 at physiological concentration combining with conditional training significantly increased the CRD-induced CPA scores, and enhanced the pain affective memory retention. In contrast, CCK had no effect on CPA induced by non-nociceptive aversive stimulus (U69,593. The physiological implications were further strengthened by the similar effects observed in the rats with duodenal infusion of 5% peptone, which has been shown to induce increases in plasma CCK levels. CCK-8 receptor antagonist CR-1409 or perivagal application of capsaicin abolished the effect of CCK on aversive visceral pain memory, which was consistent with the notion that vagal afferent modulates affective aspects of visceral pain. CCK does not change

  18. Cholecystokinin enhances visceral pain-related affective memory via vagal afferent pathway in rats.

    Science.gov (United States)

    Cao, Bing; Zhang, Xu; Yan, Ni; Chen, Shengliang; Li, Ying

    2012-06-09

    Pain contains both sensory and affective dimensions. Using a rodent visceral pain assay that combines the colorectal distension (CRD) model with the conditioned place avoidance (CPA) paradigms, we measured a learned behavior that directly reflects the affective component of visceral pain, and showed that perigenual anterior cingulate cortex (pACC) activation is critical for memory processing involved in long-term visceral affective state and prediction of aversive stimuli by contextual cue. Progress has been made and suggested that activation of vagal afferents plays a role in the behavioral control nociception and memory storage processes.In human patients, electrical vagus nerve stimulation enhanced retention of verbal learning performance. Cholecystokinin-octapeptide (CCK), which is a gastrointestinal hormone released during feeding, has been shown to enhance memory retention. Mice access to food immediately after training session enhanced memory retention. It has been well demonstrated that CCK acting on vagal afferent fibers mediates various physiological functions. We hypothesize that CCK activation of vagal afferent enhances visceral pain-related affective memory. In the presented study, infusion of CCK-8 at physiological concentration combining with conditional training significantly increased the CRD-induced CPA scores, and enhanced the pain affective memory retention. In contrast, CCK had no effect on CPA induced by non-nociceptive aversive stimulus (U69,593). The physiological implications were further strengthened by the similar effects observed in the rats with duodenal infusion of 5% peptone, which has been shown to induce increases in plasma CCK levels. CCK-8 receptor antagonist CR-1409 or perivagal application of capsaicin abolished the effect of CCK on aversive visceral pain memory, which was consistent with the notion that vagal afferent modulates affective aspects of visceral pain. CCK does not change the nociceptive response (visceral pain

  19. Enhanced dimension-specific visual working memory in grapheme–color synesthesia☆

    Science.gov (United States)

    Terhune, Devin Blair; Wudarczyk, Olga Anna; Kochuparampil, Priya; Cohen Kadosh, Roi

    2013-01-01

    There is emerging evidence that the encoding of visual information and the maintenance of this information in a temporarily accessible state in working memory rely on the same neural mechanisms. A consequence of this overlap is that atypical forms of perception should influence working memory. We examined this by investigating whether having grapheme–color synesthesia, a condition characterized by the involuntary experience of color photisms when reading or representing graphemes, would confer benefits on working memory. Two competing hypotheses propose that superior memory in synesthesia results from information being coded in two information channels (dual-coding) or from superior dimension-specific visual processing (enhanced processing). We discriminated between these hypotheses in three n-back experiments in which controls and synesthetes viewed inducer and non-inducer graphemes and maintained color or grapheme information in working memory. Synesthetes displayed superior color working memory than controls for both grapheme types, whereas the two groups did not differ in grapheme working memory. Further analyses excluded the possibilities of enhanced working memory among synesthetes being due to greater color discrimination, stimulus color familiarity, or bidirectionality. These results reveal enhanced dimension-specific visual working memory in this population and supply further evidence for a close relationship between sensory processing and the maintenance of sensory information in working memory. PMID:23892185

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

    Science.gov (United States)

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

    2010-01-01

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

  1. Impairing DNA methylation obstructs memory enhancement for at least 24?hours in Lymnaea

    OpenAIRE

    Rothwell, Cailin M.; Lukowiak, Ken D.

    2017-01-01

    ABSTRACT Stressor-induced memory enhancement has previously been shown to involve DNA methylation in the mollusc Lymnaea stagnalis. Specifically, injection of the DNA methylation inhibitor 5-AZA one hour before exposure to a memory-enhancing stressor obstructs memory augmentation. However, the duration of the influence of 5-AZA on this memory enhancement has not yet been examined. In this study, 2 memory-enhancing stressors (a thermal stress and exposure to the scent of a predator) were used ...

  2. Reward Retroactively Enhances Memory Consolidation for Related Items

    Science.gov (United States)

    Patil, Anuya; Murty, Vishnu P.; Dunsmoor, Joseph E.; Phelps, Elizabeth A.; Davachi, Lila

    2017-01-01

    Reward motivation has been shown to modulate episodic memory processes in order to support future adaptive behavior. However, for a memory system to be truly adaptive, it should enhance memory for rewarded events as well as for neutral events that may seem inconsequential at the time of encoding but can gain importance later. Here, we investigated…

  3. Oscillatory Reinstatement Enhances Declarative Memory.

    Science.gov (United States)

    Javadi, Amir-Homayoun; Glen, James C; Halkiopoulos, Sara; Schulz, Mei; Spiers, Hugo J

    2017-10-11

    Declarative memory recall is thought to involve the reinstatement of neural activity patterns that occurred previously during encoding. Consistent with this view, greater similarity between patterns of activity recorded during encoding and retrieval has been found to predict better memory performance in a number of studies. Recent models have argued that neural oscillations may be crucial to reinstatement for successful memory retrieval. However, to date, no causal evidence has been provided to support this theory, nor has the impact of oscillatory electrical brain stimulation during encoding and retrieval been assessed. To explore this we used transcranial alternating current stimulation over the left dorsolateral prefrontal cortex of human participants [ n = 70, 45 females; age mean (SD) = 22.12 (2.16)] during a declarative memory task. Participants received either the same frequency during encoding and retrieval (60-60 or 90-90 Hz) or different frequencies (60-90 or 90-60 Hz). When frequencies matched there was a significant memory improvement (at both 60 and 90 Hz) relative to sham stimulation. No improvement occurred when frequencies mismatched. Our results provide support for the role of oscillatory reinstatement in memory retrieval. SIGNIFICANCE STATEMENT Recent neurobiological models of memory have argued that large-scale neural oscillations are reinstated to support successful memory retrieval. Here we used transcranial alternating current stimulation (tACS) to test these models. tACS has recently been shown to induce neural oscillations at the frequency stimulated. We stimulated over the left dorsolateral prefrontal cortex during a declarative memory task involving learning a set of words. We found that tACS applied at the same frequency during encoding and retrieval enhances memory. We also find no difference between the two applied frequencies. Thus our results are consistent with the proposal that reinstatement of neural oscillations during retrieval

  4. Mindfulness Enhances Episodic Memory Performance: Evidence from a Multimethod Investigation.

    Directory of Open Access Journals (Sweden)

    Kirk Warren Brown

    Full Text Available Training in mindfulness, classically described as a receptive attentiveness to present events and experiences, has been shown to improve attention and working memory. Both are key to long-term memory formation, and the present three-study series used multiple methods to examine whether mindfulness would enhance episodic memory, a key form of long-term memory. In Study 1 (N = 143, a self-reported state of mindful attention predicted better recognition performance in the Remember-Know (R-K paradigm. In Study 2 (N = 93, very brief training in a focused attention form of mindfulness also produced better recognition memory performance on the R-K task relative to a randomized, well-matched active control condition. Study 3 (N = 57 extended these findings by showing that relative to randomized active and inactive control conditions the effect of very brief mindfulness training generalized to free-recall memory performance. This study also found evidence for mediation of the mindfulness training-episodic memory relation by intrinsic motivation. These findings indicate that mindful attention can beneficially impact motivation and episodic memory, with potential implications for educational and occupational performance.

  5. Chronic corticosterone exposure persistently elevates the expression of memory-related genes in the lateral amygdala and enhances the consolidation of a Pavlovian fear memory.

    Directory of Open Access Journals (Sweden)

    Melissa S Monsey

    Full Text Available Chronic exposure to stress has been widely implicated in the development of anxiety disorders, yet relatively little is known about the long-term effects of chronic stress on amygdala-dependent memory formation. Here, we examined the effects of a history of chronic exposure to the stress-associated adrenal steroid corticosterone (CORT on the consolidation of a fear memory and the expression of memory-related immediate early genes (IEGs in the lateral nucleus of the amygdala (LA. Rats received chronic exposure to CORT (50 μg/ml in their drinking water for 2 weeks and were then titrated off the CORT for an additional 6 days followed by a 2 week 'wash-out' period consisting of access to plain water. Rats were then either sacrificed to examine the expression of memory-related IEG expression in the LA or given auditory Pavlovian fear conditioning. We show that chronic exposure to CORT leads to a persistent elevation in the expression of the IEGs Arc/Arg3.1 and Egr-1 in the LA. Further, we show that rats with a history of chronic CORT exposure exhibit enhanced consolidation of a fear memory; short-term memory (STM is not affected, while long-term memory (LTM is significantly enhanced. Treatment with the selective serotonin reuptake inhibitor (SSRI fluoxetine following the chronic CORT exposure period was observed to effectively reverse both the persistent CORT-related increases in memory-related IEG expression in the LA and the CORT-related enhancement in fear memory consolidation. Our findings suggest that chronic exposure to CORT can regulate memory-related IEG expression and fear memory consolidation processes in the LA in a long-lasting manner and that treatment with fluoxetine can reverse these effects.

  6. Chronic corticosterone exposure persistently elevates the expression of memory-related genes in the lateral amygdala and enhances the consolidation of a Pavlovian fear memory.

    Science.gov (United States)

    Monsey, Melissa S; Boyle, Lara M; Zhang, Melinda L; Nguyen, Caroline P; Kronman, Hope G; Ota, Kristie T; Duman, Ronald S; Taylor, Jane R; Schafe, Glenn E

    2014-01-01

    Chronic exposure to stress has been widely implicated in the development of anxiety disorders, yet relatively little is known about the long-term effects of chronic stress on amygdala-dependent memory formation. Here, we examined the effects of a history of chronic exposure to the stress-associated adrenal steroid corticosterone (CORT) on the consolidation of a fear memory and the expression of memory-related immediate early genes (IEGs) in the lateral nucleus of the amygdala (LA). Rats received chronic exposure to CORT (50 μg/ml) in their drinking water for 2 weeks and were then titrated off the CORT for an additional 6 days followed by a 2 week 'wash-out' period consisting of access to plain water. Rats were then either sacrificed to examine the expression of memory-related IEG expression in the LA or given auditory Pavlovian fear conditioning. We show that chronic exposure to CORT leads to a persistent elevation in the expression of the IEGs Arc/Arg3.1 and Egr-1 in the LA. Further, we show that rats with a history of chronic CORT exposure exhibit enhanced consolidation of a fear memory; short-term memory (STM) is not affected, while long-term memory (LTM) is significantly enhanced. Treatment with the selective serotonin reuptake inhibitor (SSRI) fluoxetine following the chronic CORT exposure period was observed to effectively reverse both the persistent CORT-related increases in memory-related IEG expression in the LA and the CORT-related enhancement in fear memory consolidation. Our findings suggest that chronic exposure to CORT can regulate memory-related IEG expression and fear memory consolidation processes in the LA in a long-lasting manner and that treatment with fluoxetine can reverse these effects.

  7. Enhanced dimension-specific visual working memory in grapheme-color synesthesia.

    Science.gov (United States)

    Terhune, Devin Blair; Wudarczyk, Olga Anna; Kochuparampil, Priya; Cohen Kadosh, Roi

    2013-10-01

    There is emerging evidence that the encoding of visual information and the maintenance of this information in a temporarily accessible state in working memory rely on the same neural mechanisms. A consequence of this overlap is that atypical forms of perception should influence working memory. We examined this by investigating whether having grapheme-color synesthesia, a condition characterized by the involuntary experience of color photisms when reading or representing graphemes, would confer benefits on working memory. Two competing hypotheses propose that superior memory in synesthesia results from information being coded in two information channels (dual-coding) or from superior dimension-specific visual processing (enhanced processing). We discriminated between these hypotheses in three n-back experiments in which controls and synesthetes viewed inducer and non-inducer graphemes and maintained color or grapheme information in working memory. Synesthetes displayed superior color working memory than controls for both grapheme types, whereas the two groups did not differ in grapheme working memory. Further analyses excluded the possibilities of enhanced working memory among synesthetes being due to greater color discrimination, stimulus color familiarity, or bidirectionality. These results reveal enhanced dimension-specific visual working memory in this population and supply further evidence for a close relationship between sensory processing and the maintenance of sensory information in working memory. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Post-learning arousal enhances veridical memory and reduces false memory in the Deese-Roediger-McDermott paradigm.

    Science.gov (United States)

    Nielson, Kristy A; Correro, Anthony N

    2017-10-01

    The Deese-Roediger-McDermott (DRM) paradigm examines false memory by introducing words associated with a non-presented 'critical lure' as memoranda, which typically causes the lures to be remembered as frequently as studied words. Our prior work has shown enhanced veridical memory and reduced misinformation effects when arousal is induced after learning (i.e., during memory consolidation). These effects have not been examined in the DRM task, or with signal detection analysis, which can elucidate the mechanisms underlying memory alterations. Thus, 130 subjects studied and then immediately recalled six DRM lists, one after another, and then watched a 3-min arousing (n=61) or neutral (n=69) video. Recognition tested 70min later showed that arousal induced after learning led to better delayed discrimination of studied words from (a) critical lures, and (b) other non-presented 'weak associates.' Furthermore, arousal reduced liberal response bias (i.e., the tendency toward accepting dubious information) for studied words relative to all foils, including critical lures and 'weak associates.' Thus, arousal induced after learning effectively increased the distinction between signal and noise by enhancing access to verbatim information and reducing endorsement of dubious information. These findings provide important insights into the cognitive mechanisms by which arousal modulates early memory consolidation processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Collaboration enhances later individual memory for emotional material.

    Science.gov (United States)

    Bärthel, Gwennis A; Wessel, Ineke; Huntjens, Rafaële J C; Verwoerd, Johan

    2017-05-01

    Research on collaborative remembering suggests that collaboration hampers group memory (i.e., collaborative inhibition), yet enhances later individual memory. Studies examining collaborative effects on memory for emotional stimuli are scarce, especially concerning later individual memory. In the present study, female undergraduates watched an emotional movie and recalled it either collaboratively (n = 60) or individually (n = 60), followed by an individual free recall test and a recognition test. We replicated the standard collaborative inhibition effect. Further, in line with the literature, the collaborative condition displayed better post-collaborative individual memory. More importantly, in post-collaborative free recall, the centrality of the information to the movie plot did not play an important role. Recognition rendered slightly different results. Although collaboration rendered more correct recognition for more central details, it did not enhance recognition of background details. Secondly, the collaborative and individual conditions did not differ with respect to overlap of unique correct items in free recall. Yet, during recognition former collaborators more unanimously endorsed correct answers, as well as errors. Finally, extraversion, neuroticism, social anxiety, and depressive symptoms did not moderate the influence of collaboration on memory. Implications for the fields of forensic and clinical psychology are discussed.

  10. Context-dependent enhancement of declarative memory performance following acute psychosocial stress.

    Science.gov (United States)

    Smeets, T; Giesbrecht, T; Jelicic, M; Merckelbach, H

    2007-09-01

    Studies on how acute stress affects learning and memory have yielded inconsistent findings, with some studies reporting enhancing effects while others report impairing effects. Recently, Joëls et al. [Joëls, M., Pu, Z., Wiegert, O., Oitzl, M.S., Krugers, H.J., 2006. Learning under stress: how does it work? Trends in Cognitive Sciences, 10, 152-158] argued that stress will enhance memory only when the memory acquisition phase and stressor share the same spatiotemporal context (i.e., context-congruency). The current study tested this hypothesis by looking at whether context-congruent stress enhances declarative memory performance. Undergraduates were assigned to a personality stress group (n=16), a memory stress group (n=18), or a no-stress control group (n=18). While being exposed to the acute stressor or a control task, participants encoded personality- and memory-related words and were tested for free recall 24h later. Relative to controls, stress significantly enhanced recall of context-congruent words, but only for personality words. This suggests that acute stress may strengthen the consolidation of memory material when the stressor matches the to-be-remembered information in place and time.

  11. Memory-enhancing activity of Anacyclus pyrethrum in albino Wistar rats

    Directory of Open Access Journals (Sweden)

    K Sujith

    2012-08-01

    Full Text Available Objective: To explore the potential effect of ethanolic extract of Anacyclus pyrethrum (A. pyrethrum in memory dysfunction. Methods: Memory impairment was produced by administration of scopolamine (1mg/kg i. p in rats. Passive avoidance paradigms, elevated plus maze and social learning task was used to assess learning and memory. Results: A. pyrethrum extract treated group decreased transfer latency in elevated plus maze model paradigm which is an indicative of cognition improvement. In case of passive avoidance paradigm extract treated group exhibited prounced effect in reversal of scopolamine induced amnesia which was revealed by increase in step down latency. Social learning task also revealed the memory enhancing activity of A. pyrethrum extract. Conclusions: Ethanolic extract of A. pyrethrum has been demonstrated to improve cognitive processes by enhancing memory in different experimental paradigms such as passive avoidance paradigms, elevated plus maze and social learning task when administered orallyBrain cholinesterase level was measured to assess central cholinergic activity. The treatment with drugs, which increase cholinergic neurotransmission, causes an improvement in cognitive deficits. The present study suggest that ethanolic extract of A. pyrethrum increased brain cholinesterase level and hence it possess memory enhancing activity in scopolamine induced amnesia model by enhancing central cholinergic neurotransmission.

  12. Flavonoid fisetin promotes ERK-dependent long-term potentiation and enhances memory

    Science.gov (United States)

    Maher, Pamela; Akaishi, Tatsuhiro; Abe, Kazuho

    2006-01-01

    Small molecules that activate signaling pathways used by neurotrophic factors could be useful for treating CNS disorders. Here we show that the flavonoid fisetin activates ERK and induces cAMP response element-binding protein (CREB) phosphorylation in rat hippocampal slices, facilitates long-term potentiation in rat hippocampal slices, and enhances object recognition in mice. Together, these data demonstrate that the natural product fisetin can facilitate long-term memory, and therefore it may be useful for treating patients with memory disorders. PMID:17050681

  13. Erythropoietin enhances hippocampal long-term potentiation and memory

    Directory of Open Access Journals (Sweden)

    El-Kordi Ahmed

    2008-09-01

    Full Text Available Abstract Background Erythropoietin (EPO improves cognition of human subjects in the clinical setting by as yet unknown mechanisms. We developed a mouse model of robust cognitive improvement by EPO to obtain the first clues of how EPO influences cognition, and how it may act on hippocampal neurons to modulate plasticity. Results We show here that a 3-week treatment of young mice with EPO enhances long-term potentiation (LTP, a cellular correlate of learning processes in the CA1 region of the hippocampus. This treatment concomitantly alters short-term synaptic plasticity and synaptic transmission, shifting the balance of excitatory and inhibitory activity. These effects are accompanied by an improvement of hippocampus dependent memory, persisting for 3 weeks after termination of EPO injections, and are independent of changes in hematocrit. Networks of EPO-treated primary hippocampal neurons develop lower overall spiking activity but enhanced bursting in discrete neuronal assemblies. At the level of developing single neurons, EPO treatment reduces the typical increase in excitatory synaptic transmission without changing the number of synaptic boutons, consistent with prolonged functional silencing of synapses. Conclusion We conclude that EPO improves hippocampus dependent memory by modulating plasticity, synaptic connectivity and activity of memory-related neuronal networks. These mechanisms of action of EPO have to be further exploited for treating neuropsychiatric diseases.

  14. Impairing DNA methylation obstructs memory enhancement for at least 24 hours in Lymnaea.

    Science.gov (United States)

    Rothwell, Cailin M; Lukowiak, Ken D

    2017-01-01

    Stressor-induced memory enhancement has previously been shown to involve DNA methylation in the mollusc Lymnaea stagnalis . Specifically, injection of the DNA methylation inhibitor 5-AZA one hour before exposure to a memory-enhancing stressor obstructs memory augmentation. However, the duration of the influence of 5-AZA on this memory enhancement has not yet been examined. In this study, 2 memory-enhancing stressors (a thermal stress and exposure to the scent of a predator) were used to examine whether injection of the DNA methylation inhibitor 5-AZA 24 hours before stress exposure would still impair memory enhancement. Indeed, it was observed that memory is still obstructed when 5-AZA is injected 24 hours before exposure to either of these stressors in Lymnaea . Understanding that 5-AZA still effectively impairs memory enhancement after a period of 24 hours is valuable because it indicates that experimental manipulations do not need to be made within one hour after the injection of this DNA methylation inhibitor and can instead be made within one day (i.e. 24 hours). These results will allow for a future examination of the possible involvement of DNA methylation in memory enhancement related to longer-term stressors or environmental changes. This study further elucidates the involvement of epigenetic changes in memory enhancement in Lymnaea , providing insight into the process of memory formation in this mollusc.

  15. Consolidation power of extrinsic rewards: reward cues enhance long-term memory for irrelevant past events.

    Science.gov (United States)

    Murayama, Kou; Kitagami, Shinji

    2014-02-01

    Recent research suggests that extrinsic rewards promote memory consolidation through dopaminergic modulation processes. However, no conclusive behavioral evidence exists given that the influence of extrinsic reward on attention and motivation during encoding and consolidation processes are inherently confounded. The present study provides behavioral evidence that extrinsic rewards (i.e., monetary incentives) enhance human memory consolidation independently of attention and motivation. Participants saw neutral pictures, followed by a reward or control cue in an unrelated context. Our results (and a direct replication study) demonstrated that the reward cue predicted a retrograde enhancement of memory for the preceding neutral pictures. This retrograde effect was observed only after a delay, not immediately upon testing. An additional experiment showed that emotional arousal or unconscious resource mobilization cannot explain the retrograde enhancement effect. These results provide support for the notion that the dopaminergic memory consolidation effect can result from extrinsic reward.

  16. Accounting for immediate emotional memory enhancement

    OpenAIRE

    Talmi, Deborah; McGarry, Lucy M.

    2012-01-01

    Memory for emotional events is usually very good even when tested shortly after study, before it is altered by the influence of emotional arousal on consolidation. Immediate emotion-enhanced memory may stem from the influence of emotion on cognitive processes at encoding and retrieval. Our goal was to test which cognitive factors are necessary and sufficient to account for EEM, with a specific focus on clarifying the contribution of attention to this effect. In two experiments, participants e...

  17. Enhanced long-term and impaired short-term spatial memory in GluA1 AMPA receptor subunit knockout mice: evidence for a dual-process memory model.

    Science.gov (United States)

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

    2009-06-01

    The GluA1 AMPA receptor subunit is a key mediator of hippocampal synaptic plasticity and is especially important for a rapidly-induced, short-lasting form of potentiation. GluA1 gene deletion impairs hippocampus-dependent, spatial working memory, but spares hippocampus-dependent spatial reference memory. These findings may reflect the necessity of GluA1-dependent synaptic plasticity for short-term memory of recently visited places, but not for the ability to form long-term associations between a particular spatial location and an outcome. This hypothesis is in concordance with the theory that short-term and long-term memory depend on dissociable psychological processes. In this study we tested GluA1-/- mice on both short-term and long-term spatial memory using a simple novelty preference task. Mice were given a series of repeated exposures to a particular spatial location (the arm of a Y-maze) before their preference for a novel spatial location (the unvisited arm of the maze) over the familiar spatial location was assessed. GluA1-/- mice were impaired if the interval between the trials was short (1 min), but showed enhanced spatial memory if the interval between the trials was long (24 h). This enhancement was caused by the interval between the exposure trials rather than the interval prior to the test, thus demonstrating enhanced learning and not simply enhanced performance or expression of memory. This seemingly paradoxical enhancement of hippocampus-dependent spatial learning may be caused by GluA1 gene deletion reducing the detrimental effects of short-term memory on subsequent long-term learning. Thus, these results support a dual-process model of memory in which short-term and long-term memory are separate and sometimes competitive processes.

  18. Stochastic memory: Memory enhancement due to noise

    Science.gov (United States)

    Stotland, Alexander; di Ventra, Massimiliano

    2012-01-01

    There are certain classes of resistors, capacitors, and inductors that, when subject to a periodic input of appropriate frequency, develop hysteresis loops in their characteristic response. Here we show that the hysteresis of such memory elements can also be induced by white noise of appropriate intensity even at very low frequencies of the external driving field. We illustrate this phenomenon using a physical model of memory resistor realized by TiO2 thin films sandwiched between metallic electrodes and discuss under which conditions this effect can be observed experimentally. We also discuss its implications on existing memory systems described in the literature and the role of colored noise.

  19. The role of attention and relatedness in emotionally enhanced memory.

    Science.gov (United States)

    Talmi, Deborah; Schimmack, Ulrich; Paterson, Theone; Moscovitch, Morris

    2007-02-01

    Examining the positive and negative pictures separately revealed that emotionally enhanced memory (EEM) for positive pictures was mediated by attention, with no significant influence of emotional arousal, whereas the reverse was true of negative pictures. Consistent with this finding, in Experiment 2 EEM for negative pictures was found even when task emphasis was manipulated so that equivalent attention was allocated to negative and neutral pictures. The results show that attention and semantic relatedness contribute to EEM, with the extent varying with emotional valence. Negative emotion can influence memory independently of these 2 factors. (c) 2007 APA, all rights reserved.

  20. Enhanced memory effect with embedded graphene nanoplatelets in ZnO charge trapping layer

    International Nuclear Information System (INIS)

    El-Atab, Nazek; Nayfeh, Ammar; Cimen, Furkan; Alkis, Sabri; Okyay, Ali K.

    2014-01-01

    A charge trapping memory with graphene nanoplatelets embedded in atomic layer deposited ZnO (GNIZ) is demonstrated. The memory shows a large threshold voltage V t shift (4 V) at low operating voltage (6/−6 V), good retention (>10 yr), and good endurance characteristic (>10 4 cycles). This memory performance is compared to control devices with graphene nanoplatelets (or ZnO) and a thicker tunnel oxide. These structures showed a reduced V t shift and retention characteristic. The GNIZ structure allows for scaling down the tunnel oxide thickness along with improving the memory window and retention of data. The larger V t shift indicates that the ZnO adds available trap states and enhances the emission and retention of charges. The charge emission mechanism in the memory structures with graphene nanoplatelets at an electric field E ≥ 5.57 MV/cm is found to be based on Fowler-Nordheim tunneling. The fabrication of this memory device is compatible with current semiconductor processing, therefore, has great potential in low-cost nano-memory applications.

  1. Emotional Memories Are Not All Created Equal: Evidence for Selective Memory Enhancement

    Science.gov (United States)

    Anderson, Adam K.; Grabski, Wojtek; Lacka, Dominika; Yamaguchi, Yuki

    2006-01-01

    Human brain imaging studies have shown that greater amygdala activation to emotional relative to neutral events leads to enhanced episodic memory. Other studies have shown that fearful faces also elicit greater amygdala activation relative to neutral faces. To the extent that amygdala recruitment is sufficient to enhance recollection, these…

  2. Enhanced tactile encoding and memory recognition in congenital blindness.

    Science.gov (United States)

    D'Angiulli, Amedeo; Waraich, Paul

    2002-06-01

    Several behavioural studies have shown that early-blind persons possess superior tactile skills. Since neurophysiological data show that early-blind persons recruit visual as well as somatosensory cortex to carry out tactile processing (cross-modal plasticity), blind persons' sharper tactile skills may be related to cortical re-organisation resulting from loss of vision early in their life. To examine the nature of blind individuals' tactile superiority and its implications for cross-modal plasticity, we compared the tactile performance of congenitally totally blind, low-vision and sighted children on raised-line picture identification test and re-test, assessing effects of task familiarity, exploratory strategy and memory recognition. What distinguished the blind from the other children was higher memory recognition and higher tactile encoding associated with efficient exploration. These results suggest that enhanced perceptual encoding and recognition memory may be two cognitive correlates of cross-modal plasticity in congenital blindness.

  3. Grin1 receptor deletion within CRF neurons enhances fear memory.

    Directory of Open Access Journals (Sweden)

    Georgette Gafford

    Full Text Available Corticotropin releasing factor (CRF dysregulation is implicated in mood and anxiety disorders such as posttraumatic stress disorder (PTSD. CRF is expressed in areas engaged in fear and anxiety processing including the central amygdala (CeA. Complicating our ability to study the contribution of CRF-containing neurons to fear and anxiety behavior is the wide variety of cell types in which CRF is expressed. To manipulate specific subpopulations of CRF containing neurons, our lab has developed a mouse with a Cre recombinase gene driven by a CRF promoter (CRFp3.0Cre (Martin et al., 2010. In these studies, mice that have the gene that encodes NR1 (Grin1 flanked by loxP sites (floxed were crossed with our previously developed CRFp3.0Cre mouse to selectively disrupt Grin1 within CRF containing neurons (Cre+/fGrin1+. We find that disruption of Grin1 in CRF neurons did not affect baseline levels of anxiety, locomotion, pain sensitivity or exploration of a novel object. However, baseline expression of Grin1 was decreased in Cre+/fGrin1+ mice as measured by RTPCR. Cre+/fGrin1+ mice showed enhanced auditory fear acquisition and retention without showing any significant effect on fear extinction. We measured Gria1, the gene that encodes AMPAR1 and the CREB activator Creb1 in the amygdala of Cre+/fGrin1+ mice after fear conditioning. Both Gria1 and Creb1 were enhanced in the amygdala after training. To determine if the Grin1-expressing CRF neurons within the CeA are responsible for the enhancement of fear memory in adults, we infused a lentivirus with Cre driven by a CRF promoter (LV pCRF-Cre/fGrin1+ into the CeA of floxed Grin1 mice. Cre driven deletion of Grin1 specifically within CRF expressing cells in the CeA also resulted in enhanced fear memory acquisition and retention. Altogether, these findings suggest that selective disruption of Grin1 within CeA CRF neurons strongly enhances fear memory.

  4. Frontal and temporal lobe contributions to emotional enhancement of memory in behavioural-variant frontotemporal dementia and Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Fiona eKumfor

    2014-06-01

    Full Text Available Emotional events gain special priority in how they are remembered, with emotionally arousing events typically recalled more vividly and with greater confidence than non-emotional events. In dementia, memory and emotion processing are affected to varying degrees, however, whether emotional enhancement of memory for complex ecologically valid events is differentially affected across dementia syndromes remains unclear, with previous studies examining effects of emotion on simple visual recognition only. Here, we examined memory for an emotionally arousing short story and a closely matched, emotionally neutral story in behavioural-variant frontotemporal dementia (bvFTD (n = 13 and Alzheimer’s disease (AD (n = 14, and contrasted their performance with healthy controls (n = 12. Multiple-choice recognition memory for specific details of the story was assessed after a 1-hour delay. While AD and control groups showed enhanced memory for the emotional story, the bvFTD group recalled a similar number of details from the emotional and neutral stories. Voxel-based morphometry analyses revealed emotional enhancement of memory correlated with distinct brain regions in each patient group. In AD, emotional enhancement was associated with integrity of the bilateral hippocampus, parahippocampal gyri, temporal fusiform gyrus and frontal pole, regions implicated in memory processes. In contrast in bvFTD, integrity of emotion processing regions, including the orbitofrontal cortex, right amygdala and right insula, correlated with the extent emotion enhanced memory. Our results reveal that integrity of frontal and temporal regions determine the quality and nature of emotional memories. While emotional enhancement of memory is present in mild AD, in bvFTD emotion does not facilitate memory retrieval for complex realistic events. This attenuation of emotional enhancement is due to degradation of emotion processing regions, which may be important for modulating levels

  5. Brief, pre-learning stress reduces false memory production and enhances true memory selectively in females.

    Science.gov (United States)

    Zoladz, Phillip R; Peters, David M; Kalchik, Andrea E; Hoffman, Mackenzie M; Aufdenkampe, Rachael L; Woelke, Sarah A; Wolters, Nicholas E; Talbot, Jeffery N

    2014-04-10

    Some of the previous research on stress-memory interactions has suggested that stress increases the production of false memories. However, as accumulating work has shown that the effects of stress on learning and memory depend critically on the timing of the stressor, we hypothesized that brief stress administered immediately before learning would reduce, rather than increase, false memory production. In the present study, participants submerged their dominant hand in a bath of ice cold water (stress) or sat quietly (no stress) for 3 min. Then, participants completed a short-term memory task, the Deese-Roediger-McDermott paradigm, in which they were presented with 10 different lists of semantically related words (e.g., candy, sour, sugar) and, after each list, were tested for their memory of presented words (e.g., candy), non-presented unrelated "distractor" words (e.g., hat), and non-presented semantically related "critical lure" words (e.g., sweet). Stress, overall, significantly reduced the number of critical lures recalled (i.e., false memory) by participants. In addition, stress enhanced memory for the presented words (i.e., true memory) in female, but not male, participants. These findings reveal that stress does not unequivocally enhance false memory production and that the timing of the stressor is an important variable that could mediate such effects. Such results could have important implications for understanding the dependability of eyewitness accounts of events that are observed following stress. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Cognitive control in auditory working memory is enhanced in musicians

    DEFF Research Database (Denmark)

    Pallesen, Karen Johanne; Brattico, Elvira; Bailey, Christopher J

    2010-01-01

    focus on task-relevant stimuli, a skill which is crucial to working memory. We measured the blood oxygenation-level dependent (BOLD) activation signal in musicians and non-musicians during working memory of musical sounds to determine the relation among performance, musical competence and generally...... hemisphere, and bilaterally in the posterior dorsal prefrontal cortex and anterior cingulate gyrus. The relationship between the task performance and the magnitude of the BOLD response was more positive in musicians than in non-musicians, particularly during the most difficult working memory task....... The results confirm previous findings that neural activity increases during enhanced working memory performance. The results also suggest that superior working memory task performance in musicians rely on an enhanced ability to exert sustained cognitive control. This cognitive benefit in musicians may...

  7. Upregulation of CREB-mediated transcription enhances both short- and long-term memory.

    Science.gov (United States)

    Suzuki, Akinobu; Fukushima, Hotaka; Mukawa, Takuya; Toyoda, Hiroki; Wu, Long-Jun; Zhao, Ming-Gao; Xu, Hui; Shang, Yuze; Endoh, Kengo; Iwamoto, Taku; Mamiya, Nori; Okano, Emiko; Hasegawa, Shunsuke; Mercaldo, Valentina; Zhang, Yue; Maeda, Ryouta; Ohta, Miho; Josselyn, Sheena A; Zhuo, Min; Kida, Satoshi

    2011-06-15

    Unraveling the mechanisms by which the molecular manipulation of genes of interest enhances cognitive function is important to establish genetic therapies for cognitive disorders. Although CREB is thought to positively regulate formation of long-term memory (LTM), gain-of-function effects of CREB remain poorly understood, especially at the behavioral level. To address this, we generated four lines of transgenic mice expressing dominant active CREB mutants (CREB-Y134F or CREB-DIEDML) in the forebrain that exhibited moderate upregulation of CREB activity. These transgenic lines improved not only LTM but also long-lasting long-term potentiation in the CA1 area in the hippocampus. However, we also observed enhanced short-term memory (STM) in contextual fear-conditioning and social recognition tasks. Enhanced LTM and STM could be dissociated behaviorally in these four lines of transgenic mice, suggesting that the underlying mechanism for enhanced STM and LTM are distinct. LTM enhancement seems to be attributable to the improvement of memory consolidation by the upregulation of CREB transcriptional activity, whereas higher basal levels of BDNF, a CREB target gene, predicted enhanced shorter-term memory. The importance of BDNF in STM was verified by microinfusing BDNF or BDNF inhibitors into the hippocampus of wild-type or transgenic mice. Additionally, increasing BDNF further enhanced LTM in one of the lines of transgenic mice that displayed a normal BDNF level but enhanced LTM, suggesting that upregulation of BDNF and CREB activity cooperatively enhances LTM formation. Our findings suggest that CREB positively regulates memory consolidation and affects memory performance by regulating BDNF expression.

  8. Methylphenidate produces selective enhancement of declarative memory consolidation in healthy volunteers.

    Science.gov (United States)

    Linssen, A M W; Vuurman, E F P M; Sambeth, A; Riedel, W J

    2012-06-01

    Methylphenidate inhibits the reuptake of dopamine and noradrenaline and is used to treat children with attention deficit hyperactivity disorder (ADHD). Besides reducing behavioral symptoms, it improves their cognitive function. There are also observations of methylphenidate-induced cognition enhancement in healthy adults, although studies in this area are relatively sparse. We assessed the possible memory-enhancing properties of methylphenidate. In the current study, the possible enhancing effects of three doses of methylphenidate on declarative and working memory, attention, response inhibition and planning were investigated in healthy volunteers. In a double blind placebo-controlled crossover study, 19 healthy young male volunteers were tested after a single dose of placebo or 10, 20 or 40 mg of methylphenidate. Cognitive performance testing included a word learning test as a measure of declarative memory, a spatial working memory test, a set-shifting test, a stop signal test and a computerized version of the Tower of London planning test. Declarative memory consolidation was significantly improved relative to placebo after 20 and 40 mg of methylphenidate. Methylphenidate also improved set shifting and stopped signal task performance but did not affect spatial working memory or planning. To the best of our knowledge, this is the first study reporting enhanced declarative memory consolidation after methylphenidate in a dose-related fashion over a dose range that is presumed to reflect a wide range of dopamine reuptake inhibition.

  9. Training Working Memory in Childhood Enhances Coupling between Frontoparietal Control Network and Task-Related Regions.

    Science.gov (United States)

    Barnes, Jessica J; Nobre, Anna Christina; Woolrich, Mark W; Baker, Kate; Astle, Duncan E

    2016-08-24

    Working memory is a capacity upon which many everyday tasks depend and which constrains a child's educational progress. We show that a child's working memory can be significantly enhanced by intensive computer-based training, relative to a placebo control intervention, in terms of both standardized assessments of working memory and performance on a working memory task performed in a magnetoencephalography scanner. Neurophysiologically, we identified significantly increased cross-frequency phase amplitude coupling in children who completed training. Following training, the coupling between the upper alpha rhythm (at 16 Hz), recorded in superior frontal and parietal cortex, became significantly coupled with high gamma activity (at ∼90 Hz) in inferior temporal cortex. This altered neural network activity associated with cognitive skill enhancement is consistent with a framework in which slower cortical rhythms enable the dynamic regulation of higher-frequency oscillatory activity related to task-related cognitive processes. Whether we can enhance cognitive abilities through intensive training is one of the most controversial topics of cognitive psychology in recent years. This is particularly controversial in childhood, where aspects of cognition, such as working memory, are closely related to school success and are implicated in numerous developmental disorders. We provide the first neurophysiological account of how working memory training may enhance ability in childhood, using a brain recording technique called magnetoencephalography. We borrowed an analysis approach previously used with intracranial recordings in adults, or more typically in other animal models, called "phase amplitude coupling." Copyright © 2016 Barnes et al.

  10. Transient acidosis while retrieving a fear-related memory enhances its lability

    Science.gov (United States)

    Du, Jianyang; Price, Margaret P; Taugher, Rebecca J; Grigsby, Daniel; Ash, Jamison J; Stark, Austin C; Hossain Saad, Md Zubayer; Singh, Kritika; Mandal, Juthika; Wemmie, John A; Welsh, Michael J

    2017-01-01

    Attenuating the strength of fearful memories could benefit people disabled by memories of past trauma. Pavlovian conditioning experiments indicate that a retrieval cue can return a conditioned aversive memory to a labile state. However, means to enhance retrieval and render a memory more labile are unknown. We hypothesized that augmenting synaptic signaling during retrieval would increase memory lability. To enhance synaptic transmission, mice inhaled CO2 to induce an acidosis and activate acid sensing ion channels. Transient acidification increased the retrieval-induced lability of an aversive memory. The labile memory could then be weakened by an extinction protocol or strengthened by reconditioning. Coupling CO2 inhalation to retrieval increased activation of amygdala neurons bearing the memory trace and increased the synaptic exchange from Ca2+-impermeable to Ca2+-permeable AMPA receptors. The results suggest that transient acidosis during retrieval renders the memory of an aversive event more labile and suggest a strategy to modify debilitating memories. DOI: http://dx.doi.org/10.7554/eLife.22564.001 PMID:28650315

  11. Enhanced odor discrimination and impaired olfactory memory by spatially controlled switch of AMPA receptors.

    Science.gov (United States)

    Shimshek, Derya R; Bus, Thorsten; Kim, Jinhyun; Mihaljevic, Andre; Mack, Volker; Seeburg, Peter H; Sprengel, Rolf; Schaefer, Andreas T

    2005-11-01

    Genetic perturbations of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptors (AMPARs) are widely used to dissect molecular mechanisms of sensory coding, learning, and memory. In this study, we investigated the role of Ca2+-permeable AMPARs in olfactory behavior. AMPAR modification was obtained by depletion of the GluR-B subunit or expression of unedited GluR-B(Q), both leading to increased Ca2+ permeability of AMPARs. Mice with this functional AMPAR switch, specifically in forebrain, showed enhanced olfactory discrimination and more rapid learning in a go/no-go operant conditioning task. Olfactory memory, however, was dramatically impaired. GluR-B depletion in forebrain was ectopically variable ("mosaic") among individuals and strongly correlated with decreased olfactory memory in hippocampus and cortex. Accordingly, memory was rescued by transgenic GluR-B expression restricted to piriform cortex and hippocampus, while enhanced odor discrimination was independent of both GluR-B variability and transgenic GluR-B expression. Thus, correlated differences in behavior and levels of GluR-B expression allowed a mechanistic and spatial dissection of olfactory learning, discrimination, and memory capabilities.

  12. Enhanced recognition memory after incidental encoding in children with developmental dyslexia.

    Directory of Open Access Journals (Sweden)

    Martina Hedenius

    Full Text Available Developmental dyslexia (DD has previously been associated with a number of cognitive deficits. Little attention has been directed to cognitive functions that remain intact in the disorder, though the investigation and identification of such strengths might be useful for developing new, and improving current, therapeutical interventions. In this study, an old/new recognition memory paradigm was used to examine previously untested aspects of declarative memory in children with DD and typically developing control children. The DD group was not only not impaired at the task, but actually showed superior recognition memory, as compared to the control children. These findings complement previous reports of enhanced cognition in other domains (e.g., visuo-spatial processing in DD. Possible underlying mechanisms for the observed DD advantage in declarative memory, and the possibility of compensation by this system for reading deficits in dyslexia, are discussed.

  13. Acute stress blocks the caffeine-induced enhancement of contextual memory retrieval in mice.

    Science.gov (United States)

    Pierard, Chistophe; Krazem, Ali; Henkous, Nadia; Decorte, Laurence; Béracochéa, Daniel

    2015-08-15

    This study investigated in mice the dose-effect of caffeine on memory retrieval in non-stress and stress conditions. C57 Bl/6 Jico mice learned two consecutive discriminations (D1 and D2) in a four-hole board which involved either distinct contextual (CSD) or similar contextual (SSD) cues. All mice received an i.p. injection of vehicle or caffeine (8, 16 or 32mg/kg) 30min before the test session. Results showed that in non-stress conditions, the 16mg/kg caffeine dose induced a significant enhancement of D1 performance in CSD but not in SSD. Hence, we studied the effect of an acute stress (electric footshocks) administered 15min before the test session on D1 performance in caffeine-treated mice. Results showed that stress significantly decreased D1 performance in vehicle-treated controls and the memory-enhancing effect induced by the 16mg/kg caffeine dose in non-stress condition is no longer observed. Interestingly, whereas caffeine-treated mice exhibited weaker concentrations of plasma corticosterone as compared to vehicles in non-stress condition, stress significantly increased plasma corticosterone concentrations in caffeine-treated mice which reached similar level to that of controls. Overall, the acute stress blocked both the endocrinological and memory retrieval enhancing effects of caffeine. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Enhancing early consolidation of human episodic memory by theta EEG neurofeedback.

    Science.gov (United States)

    Rozengurt, Roman; Shtoots, Limor; Sheriff, Aviv; Sadka, Ofir; Levy, Daniel A

    2017-11-01

    Consolidation of newly formed memories is readily disrupted, but can it be enhanced? Given the prominent role of hippocampal theta oscillations in memory formation and retrieval, we hypothesized that upregulating theta power during early stages of consolidation might benefit memory stability and persistence. We used EEG neurofeedback to enable participants to selectively increase theta power in their EEG spectra following episodic memory encoding, while other participants engaged in low beta-focused neurofeedback or passively viewed a neutral nature movie. Free recall assessments immediately following the interventions, 24h later and 7d later all indicated benefit to memory of theta neurofeedback, relative to low beta neurofeedback or passive movie-viewing control conditions. The degree of benefit to memory was correlated with the extent of theta power modulation, but not with other spectral changes. Theta enhancement may provide optimal conditions for stabilization of new hippocampus-dependent memories. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Intrinsic functional connectivity between amygdala and hippocampus during rest predicts enhanced memory under stress.

    Science.gov (United States)

    de Voogd, Lycia D; Klumpers, Floris; Fernández, Guillén; Hermans, Erno J

    2017-01-01

    Declarative memories of stressful events are less prone to forgetting than mundane events. Animal research has demonstrated that such stress effects on consolidation of hippocampal-dependent memories require the amygdala. In humans, it has been shown that during learning, increased amygdala-hippocampal interactions are related to more efficient memory encoding. Animal models predict that following learning, amygdala-hippocampal interactions are instrumental to strengthening the consolidation of such declarative memories. Whether this is the case in humans is unknown and remains to be empirically verified. To test this, we analyzed data from a sample of 120 healthy male participants who performed an incidental encoding task and subsequently underwent resting-state functional MRI in a stressful and a neutral context. Stress was assessed by measures of salivary cortisol, blood pressure, heart rate, and subjective ratings. Memory was tested afterwards outside of the scanner. Our data show that memory was stronger in the stress context compared to the neutral context and that stress-induced cortisol responses were associated with this memory enhancement. Interestingly, amygdala-hippocampal connectivity during post-encoding awake rest regardless of context (stress or neutral) was associated with the enhanced memory performance under stress. Thus, our findings are in line with a role for intrinsic functional connectivity during rest between the amygdala and the hippocampus in the state effects of stress on strengthening memory. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Cognitive control in auditory working memory is enhanced in musicians.

    Directory of Open Access Journals (Sweden)

    Karen Johanne Pallesen

    Full Text Available Musical competence may confer cognitive advantages that extend beyond processing of familiar musical sounds. Behavioural evidence indicates a general enhancement of both working memory and attention in musicians. It is possible that musicians, due to their training, are better able to maintain focus on task-relevant stimuli, a skill which is crucial to working memory. We measured the blood oxygenation-level dependent (BOLD activation signal in musicians and non-musicians during working memory of musical sounds to determine the relation among performance, musical competence and generally enhanced cognition. All participants easily distinguished the stimuli. We tested the hypothesis that musicians nonetheless would perform better, and that differential brain activity would mainly be present in cortical areas involved in cognitive control such as the lateral prefrontal cortex. The musicians performed better as reflected in reaction times and error rates. Musicians also had larger BOLD responses than non-musicians in neuronal networks that sustain attention and cognitive control, including regions of the lateral prefrontal cortex, lateral parietal cortex, insula, and putamen in the right hemisphere, and bilaterally in the posterior dorsal prefrontal cortex and anterior cingulate gyrus. The relationship between the task performance and the magnitude of the BOLD response was more positive in musicians than in non-musicians, particularly during the most difficult working memory task. The results confirm previous findings that neural activity increases during enhanced working memory performance. The results also suggest that superior working memory task performance in musicians rely on an enhanced ability to exert sustained cognitive control. This cognitive benefit in musicians may be a consequence of focused musical training.

  17. Money Enhances Memory Consolidation--But Only for Boring Material

    Science.gov (United States)

    Murayama, Kou; Kuhbandner, Christof

    2011-01-01

    Money's ability to enhance memory has received increased attention in recent research. However, previous studies have not directly addressed the time-dependent nature of monetary effects on memory, which are suggested to exist by research in cognitive neuroscience, and the possible detrimental effects of monetary rewards on learning interesting…

  18. Modifying Memory: Selectively Enhancing and Updating Personal Memories for a Museum Tour by Reactivating Them

    Science.gov (United States)

    St. Jacques, Peggy L.; Schacter, Daniel L.

    2013-01-01

    Memory can be modified when reactivated, but little is known about how the properties and extent of reactivation can selectively affect subsequent memory. We developed a novel museum paradigm to directly investigate reactivation-induced plasticity for personal memories. Participants reactivated memories triggered by photos taken from a camera they wore during a museum tour and made relatedness judgments on novel photos taken from a different tour of the same museum. Subsequent recognition memory for events at the museum was better for memories that were highly reactivated (i.e., the retrieval cues during reactivation matched the encoding experience) than for memories that were reactivated at a lower level (i.e., the retrieval cues during reactivation mismatched the encoding experience), but reactivation also increased false recognition of photographs depicting stops that were not experienced during the museum tour. Reactivation thus enables memories to be selectively enhanced and distorted via updating, thereby supporting the dynamic and flexible nature of memory. PMID:23406611

  19. Enhanced odor discrimination and impaired olfactory memory by spatially controlled switch of AMPA receptors.

    Directory of Open Access Journals (Sweden)

    Derya R Shimshek

    2005-11-01

    Full Text Available Genetic perturbations of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptors (AMPARs are widely used to dissect molecular mechanisms of sensory coding, learning, and memory. In this study, we investigated the role of Ca2+-permeable AMPARs in olfactory behavior. AMPAR modification was obtained by depletion of the GluR-B subunit or expression of unedited GluR-B(Q, both leading to increased Ca2+ permeability of AMPARs. Mice with this functional AMPAR switch, specifically in forebrain, showed enhanced olfactory discrimination and more rapid learning in a go/no-go operant conditioning task. Olfactory memory, however, was dramatically impaired. GluR-B depletion in forebrain was ectopically variable ("mosaic" among individuals and strongly correlated with decreased olfactory memory in hippocampus and cortex. Accordingly, memory was rescued by transgenic GluR-B expression restricted to piriform cortex and hippocampus, while enhanced odor discrimination was independent of both GluR-B variability and transgenic GluR-B expression. Thus, correlated differences in behavior and levels of GluR-B expression allowed a mechanistic and spatial dissection of olfactory learning, discrimination, and memory capabilities.

  20. Selective Attention to Auditory Memory Neurally Enhances Perceptual Precision.

    Science.gov (United States)

    Lim, Sung-Joo; Wöstmann, Malte; Obleser, Jonas

    2015-12-09

    Selective attention to a task-relevant stimulus facilitates encoding of that stimulus into a working memory representation. It is less clear whether selective attention also improves the precision of a stimulus already represented in memory. Here, we investigate the behavioral and neural dynamics of selective attention to representations in auditory working memory (i.e., auditory objects) using psychophysical modeling and model-based analysis of electroencephalographic signals. Human listeners performed a syllable pitch discrimination task where two syllables served as to-be-encoded auditory objects. Valid (vs neutral) retroactive cues were presented during retention to allow listeners to selectively attend to the to-be-probed auditory object in memory. Behaviorally, listeners represented auditory objects in memory more precisely (expressed by steeper slopes of a psychometric curve) and made faster perceptual decisions when valid compared to neutral retrocues were presented. Neurally, valid compared to neutral retrocues elicited a larger frontocentral sustained negativity in the evoked potential as well as enhanced parietal alpha/low-beta oscillatory power (9-18 Hz) during memory retention. Critically, individual magnitudes of alpha oscillatory power (7-11 Hz) modulation predicted the degree to which valid retrocues benefitted individuals' behavior. Our results indicate that selective attention to a specific object in auditory memory does benefit human performance not by simply reducing memory load, but by actively engaging complementary neural resources to sharpen the precision of the task-relevant object in memory. Can selective attention improve the representational precision with which objects are held in memory? And if so, what are the neural mechanisms that support such improvement? These issues have been rarely examined within the auditory modality, in which acoustic signals change and vanish on a milliseconds time scale. Introducing a new auditory memory

  1. Remembering the snake in the grass: Threat enhances recognition but not source memory.

    Science.gov (United States)

    Meyer, Miriam Magdalena; Bell, Raoul; Buchner, Axel

    2015-12-01

    Research on the influence of emotion on source memory has yielded inconsistent findings. The object-based framework (Mather, 2007) predicts that negatively arousing stimuli attract attention, resulting in enhanced within-object binding, and, thereby, enhanced source memory for intrinsic context features of emotional stimuli. To test this prediction, we presented pictures of threatening and harmless animals, the color of which had been experimentally manipulated. In a memory test, old-new recognition for the animals and source memory for their color was assessed. In all 3 experiments, old-new recognition was better for the more threatening material, which supports previous reports of an emotional memory enhancement. This recognition advantage was due to the emotional properties of the stimulus material, and not specific for snake stimuli. However, inconsistent with the prediction of the object-based framework, intrinsic source memory was not affected by emotion. (c) 2015 APA, all rights reserved).

  2. Memory enhancing activity of Spondias mombin Anarcadiaceae ...

    African Journals Online (AJOL)

    Background: In traditional medical practices, several plants have been used to treat cognitive disorders associated with aging as well as neurodegenerative diseases such as Alzheimer's. Spondias mombin and Pycnanthus angolensis were found among recipes used ethnomedicine in Nigeria as memory enhancer.

  3. Memory-Enhancing Activity of Palmatine in Mice Using Elevated Plus Maze and Morris Water Maze

    Directory of Open Access Journals (Sweden)

    Dinesh Dhingra

    2012-01-01

    Full Text Available The present study was designed to evaluate the effect of palmatine on memory of Swiss young male albino mice. Palmatine (0.1, 0.5, 1 mg/kg, i.p. and physostigmine (0.1 mg/kg, i.p. per se were administered for 10 successive days to separate groups of mice. Effect of drugs on learning and memory of mice was evaluated using elevated plus maze and Morris water maze. Brain acetylcholinesterase activity was also estimated. Effect of palmatine on scopolamine- and diazepam-induced amnesia was also investigated. Palmatine (0.5 and 1 mg/kg and physostigmine significantly improved learning and memory of mice, as indicated by decrease in transfer latency using elevated plus maze, and decrease in escape latency during training and increase in time spent in target quadrant during retrieval using Morris water maze. The drugs did not show any significant effect on locomotor activity of the mice. Memory-enhancing activity of palmatine (1 mg/kg was comparable to physostigmine. Palmatine (1 mg/kg significantly reversed scopolamine- and diazepam-induced amnesia in mice. Palmatine and physostigmine also significantly reduced brain acetylcholinesterase activity of mice. Thus, palmatine showed memory-enhancing activity in mice probably by inhibiting brain acetylcholinesterase activity, through involvement of GABA-benzodiazepine pathway, and due to its antioxidant activity.

  4. Sensory input from the osphradium modulates the response to memory-enhancing stressors in Lymnaea stagnalis.

    Science.gov (United States)

    Karnik, Vikram; Braun, Marvin; Dalesman, Sarah; Lukowiak, Ken

    2012-02-01

    In the freshwater environment species often rely on chemosensory information to modulate behavior. The pond snail, Lymnaea stagnalis, is a model species used to characterize the causal mechanisms of long-term memory (LTM) formation. Chemical stressors including crayfish kairomones and KCl enhance LTM formation (≥24 h) in Lymnaea; however, how these stressors are sensed and the mechanism by which they affect the electrophysiological properties of neurons necessary for memory formation are poorly understood. Here, we assessed whether the osphradium, a primary chemosensory organ in Lymnaea, modulates LTM enhancement. To test this we severed the osphradial nerve proximal to the osphradium, using sham-operated animals as controls, and assessed the behavioral and electrophysiological response to crayfish kairomones and KCl. We operantly conditioned aerial respiratory behavior in intact, sham and osphradially cut animals, and tested for enhanced memory formation after exposure to the chemical stressors. Sham-operated animals displayed the same memory enhancement as intact animals but snails with a severed osphradial nerve did not show LTM enhancement. Extracellular recordings made from the osphradial nerve demonstrate that these stressors evoked afferent sensory activity. Intracellular recordings from right pedal dorsal 1 (RPeD1), a neuron necessary for LTM formation, demonstrate that its electrophysiological activity is altered by input from the osphradium following exposure to crayfish kairomones or KCl in sham and intact animals but no response is seen in RPeD1 in osphradially cut animals. Therefore, sensory input from the osphradium is necessary for LTM enhancement following exposure to these chemical stressors.

  5. The role of attention and relatedness in emotionally enhanced memory

    OpenAIRE

    Talmi, Deborah; Schimmack, Ulrich; Paterson, Theone; Moscovitch, Morris

    2007-01-01

    Examining the positive and negative pictures separately revealed that emotionally enhanced memory (EEM) for positive pictures was mediated by attention, with no significant influence of emotional arousal, whereas the reverse was true of negative pictures. Consistent with this finding, in Experiment 2 EEM for negative pictures was found even when task emphasis was manipulated so that equivalent attention was allocated to negative and neutral pictures. The results show that attention and semant...

  6. Enhanced hippocampal long-term potentiation and fear memory in Btbd9 mutant mice.

    Directory of Open Access Journals (Sweden)

    Mark P DeAndrade

    Full Text Available Polymorphisms in BTBD9 have recently been associated with higher risk of restless legs syndrome (RLS, a neurological disorder characterized by uncomfortable sensations in the legs at rest that are relieved by movement. The BTBD9 protein contains a BTB/POZ domain and a BACK domain, but its function is unknown. To elucidate its function and potential role in the pathophysiology of RLS, we generated a line of mutant Btbd9 mice derived from a commercial gene-trap embryonic stem cell clone. Btbd9 is the mouse homolog of the human BTBD9. Proteins that contain a BTB/POZ domain have been reported to be associated with synaptic transmission and plasticity. We found that Btbd9 is naturally expressed in the hippocampus of our mutant mice, a region critical for learning and memory. As electrophysiological characteristics of CA3-CA1 synapses of the hippocampus are well characterized, we performed electrophysiological recordings in this region. The mutant mice showed normal input-output relationship, a significant impairment in pre-synaptic activity, and an enhanced long-term potentiation. We further performed an analysis of fear memory and found the mutant mice had an enhanced cued and contextual fear memory. To elucidate a possible molecular basis for these enhancements, we analyzed proteins that have been associated with synaptic plasticity. We found an elevated level of dynamin 1, an enzyme associated with endocytosis, in the mutant mice. These results suggest the first identified function of Btbd9 as being involved in regulating synaptic plasticity and memory. Recent studies have suggested that enhanced synaptic plasticity, analogous to what we have observed, in other regions of the brain could enhance sensory perception similar to what is seen in RLS patients. Further analyses of the mutant mice will help shine light on the function of BTBD9 and its role in RLS.

  7. Enhanced hippocampal long-term potentiation and fear memory in Btbd9 mutant mice.

    Science.gov (United States)

    DeAndrade, Mark P; Zhang, Li; Doroodchi, Atbin; Yokoi, Fumiaki; Cheetham, Chad C; Chen, Huan-Xin; Roper, Steven N; Sweatt, J David; Li, Yuqing

    2012-01-01

    Polymorphisms in BTBD9 have recently been associated with higher risk of restless legs syndrome (RLS), a neurological disorder characterized by uncomfortable sensations in the legs at rest that are relieved by movement. The BTBD9 protein contains a BTB/POZ domain and a BACK domain, but its function is unknown. To elucidate its function and potential role in the pathophysiology of RLS, we generated a line of mutant Btbd9 mice derived from a commercial gene-trap embryonic stem cell clone. Btbd9 is the mouse homolog of the human BTBD9. Proteins that contain a BTB/POZ domain have been reported to be associated with synaptic transmission and plasticity. We found that Btbd9 is naturally expressed in the hippocampus of our mutant mice, a region critical for learning and memory. As electrophysiological characteristics of CA3-CA1 synapses of the hippocampus are well characterized, we performed electrophysiological recordings in this region. The mutant mice showed normal input-output relationship, a significant impairment in pre-synaptic activity, and an enhanced long-term potentiation. We further performed an analysis of fear memory and found the mutant mice had an enhanced cued and contextual fear memory. To elucidate a possible molecular basis for these enhancements, we analyzed proteins that have been associated with synaptic plasticity. We found an elevated level of dynamin 1, an enzyme associated with endocytosis, in the mutant mice. These results suggest the first identified function of Btbd9 as being involved in regulating synaptic plasticity and memory. Recent studies have suggested that enhanced synaptic plasticity, analogous to what we have observed, in other regions of the brain could enhance sensory perception similar to what is seen in RLS patients. Further analyses of the mutant mice will help shine light on the function of BTBD9 and its role in RLS.

  8. Selective inhibition of phosphodiesterase 5 enhances glutamatergic synaptic plasticity and memory in mice.

    Science.gov (United States)

    Uthayathas, Subramaniam; Parameshwaran, Kodeeswaran; Karuppagounder, Senthilkumar S; Ahuja, Manuj; Dhanasekaran, Muralikrishnan; Suppiramaniam, Vishnu

    2013-11-01

    Phosphodiesterases (PDEs) belong to a family of proteins that control metabolism of cyclic nucleotides. Targeting PDE5, for enhancing cellular function, is one of the therapeutic strategies for male erectile dysfunction. We have investigated whether in vivo inhibition of PDE5, which is expressed in several brain regions, will enhance memory and synaptic transmission in the hippocampus of healthy mice. We have found that acute administration of sildenafil, a specific PDE5 inhibitor, enhanced hippocampus-dependent memory tasks. To elucidate the underlying mechanism in the memory enhancement, effects of sildenafil on long-term potentiation (LTP) were measured. The level of LTP was significantly elevated, with concomitant increases in basal synaptic transmission, in mice treated with sildenafil (1 mg/kg/day) for 15 days compared to control mice. These results suggest that moderate PDE5 inhibition enhances memory by increasing synaptic plasticity and transmission in the hippocampus. Copyright © 2013 Wiley Periodicals, Inc.

  9. Exchange Protein Activated by cAMP Enhances Long-Term Memory Formation Independent of Protein Kinase A

    Science.gov (United States)

    Ma, Nan; Abel, Ted; Hernandez, Pepe J.

    2009-01-01

    It is well established that cAMP signaling within neurons plays a major role in the formation of long-term memories--signaling thought to proceed through protein kinase A (PKA). However, here we show that exchange protein activated by cAMP (Epac) is able to enhance the formation of long-term memory in the hippocampus and appears to do so…

  10. Emotional content enhances true but not false memory for categorized stimuli.

    Science.gov (United States)

    Choi, Hae-Yoon; Kensinger, Elizabeth A; Rajaram, Suparna

    2013-04-01

    Past research has shown that emotion enhances true memory, but that emotion can either increase or decrease false memory. Two theoretical possibilities-the distinctiveness of emotional stimuli and the conceptual relatedness of emotional content-have been implicated as being responsible for influencing both true and false memory for emotional content. In the present study, we sought to identify the mechanisms that underlie these mixed findings by equating the thematic relatedness of the study materials across each type of valence used (negative, positive, or neutral). In three experiments, categorically bound stimuli (e.g., funeral, pets, and office items) were used for this purpose. When the encoding task required the processing of thematic relatedness, a significant true-memory enhancement for emotional content emerged in recognition memory, but no emotional boost to false memory (exp. 1). This pattern persisted for true memory with a longer retention interval between study and test (24 h), and false recognition was reduced for emotional items (exp. 2). Finally, better recognition memory for emotional items once again emerged when the encoding task (arousal ratings) required the processing of the emotional aspect of the study items, with no emotional boost to false recognition (EXP. 3). Together, these findings suggest that when emotional and neutral stimuli are equivalently high in thematic relatedness, emotion continues to improve true memory, but it does not override other types of grouping to increase false memory.

  11. Retrieval Practice Enhances the Accessibility but not the Quality of Memory

    OpenAIRE

    Sutterer, David W.; Awh, Edward

    2016-01-01

    Numerous studies have demonstrated that retrieval from long term memory (LTM) can enhance subsequent memory performance, a phenomenon labeled the retrieval practice effect. However, the almost exclusive reliance on categorical stimuli in this literature leaves open a basic question about the nature of this improvement in memory performance. It has not yet been determined whether retrieval practice improves the probability of successful memory retrieval or the quality of the retrieved represen...

  12. Enhancing Assisted Living Technology with Extended Visual Memory

    Directory of Open Access Journals (Sweden)

    Joo-Hwee Lim

    2011-05-01

    Full Text Available Human vision and memory are powerful cognitive faculties by which we understand the world. However, they are imperfect and further, subject to deterioration with age. We propose a cognitive-inspired computational model, Extended Visual Memory (EVM, within the Computer-Aided Vision (CAV framework, to assist human in vision-related tasks. We exploit wearable sensors such as cameras, GPS and ambient computing facilities to complement a user's vision and memory functions by answering four types of queries central to visual activities, namely, Retrieval, Understanding, Navigation and Search. Learning of EVM relies on both frequency-based and attention-driven mechanisms to store view-based visual fragments (VF, which are abstracted into high-level visual schemas (VS, both in the visual long-term memory. During inference, the visual short-term memory plays a key role in visual similarity computation between input (or its schematic representation and VF, exemplified from VS when necessary. We present an assisted living scenario, termed EViMAL (Extended Visual Memory for Assisted Living, targeted at mild dementia patients to provide novel functions such as hazard-warning, visual reminder, object look-up and event review. We envisage EVM having the potential benefits in alleviating memory loss, improving recall precision and enhancing memory capacity through external support.

  13. Caffeine in floral nectar enhances a pollinator's memory of reward.

    Science.gov (United States)

    Wright, G A; Baker, D D; Palmer, M J; Stabler, D; Mustard, J A; Power, E F; Borland, A M; Stevenson, P C

    2013-03-08

    Plant defense compounds occur in floral nectar, but their ecological role is not well understood. We provide evidence that plant compounds pharmacologically alter pollinator behavior by enhancing their memory of reward. Honeybees rewarded with caffeine, which occurs naturally in nectar of Coffea and Citrus species, were three times as likely to remember a learned floral scent as were honeybees rewarded with sucrose alone. Caffeine potentiated responses of mushroom body neurons involved in olfactory learning and memory by acting as an adenosine receptor antagonist. Caffeine concentrations in nectar did not exceed the bees' bitter taste threshold, implying that pollinators impose selection for nectar that is pharmacologically active but not repellent. By using a drug to enhance memories of reward, plants secure pollinator fidelity and improve reproductive success.

  14. Music-based memory enhancement in Alzheimer's disease: promise and limitations.

    Science.gov (United States)

    Simmons-Stern, Nicholas R; Deason, Rebecca G; Brandler, Brian J; Frustace, Bruno S; O'Connor, Maureen K; Ally, Brandon A; Budson, Andrew E

    2012-12-01

    In a previous study (Simmons-Stern, Budson & Ally, 2010), we found that patients with Alzheimer's disease (AD) better recognized visually presented lyrics when the lyrics were also sung rather than spoken at encoding. The present study sought to further investigate the effects of music on memory in patients with AD by making the content of the song lyrics relevant for the daily life of an older adult and by examining how musical encoding alters several different aspects of episodic memory. Patients with AD and healthy older adults studied visually presented novel song lyrics related to instrumental activities of daily living (IADL) that were accompanied by either a sung or a spoken recording. Overall, participants performed better on a memory test of general lyric content for lyrics that were studied sung as compared to spoken. However, on a memory test of specific lyric content, participants performed equally well for sung and spoken lyrics. We interpret these results in terms of a dual-process model of recognition memory such that the general content questions represent a familiarity-based representation that is preferentially sensitive to enhancement via music, while the specific content questions represent a recollection-based representation unaided by musical encoding. Additionally, in a test of basic recognition memory for the audio stimuli, patients with AD demonstrated equal discrimination for sung and spoken stimuli. We propose that the perceptual distinctiveness of musical stimuli enhanced metamemorial awareness in AD patients via a non-selective distinctiveness heuristic, thereby reducing false recognition while at the same time reducing true recognition and eliminating the mnemonic benefit of music. These results are discussed in the context of potential music-based memory enhancement interventions for the care of patients with AD. Published by Elsevier Ltd.

  15. Overexpression of Protein Kinase Mζ in the Hippocampus Enhances Long-Term Potentiation and Long-Term Contextual But Not Cued Fear Memory in Rats.

    Science.gov (United States)

    Schuette, Sven R M; Fernández-Fernández, Diego; Lamla, Thorsten; Rosenbrock, Holger; Hobson, Scott

    2016-04-13

    The persistently active protein kinase Mζ (PKMζ) has been found to be involved in the formation and maintenance of long-term memory. Most of the studies investigating PKMζ, however, have used either putatively unselective inhibitors or conventional knock-out animal models in which compensatory mechanisms may occur. Here, we overexpressed an active form of PKMζ in rat hippocampus, a structure highly involved in memory formation, and embedded in several neural networks. We investigated PKMζ's influence on synaptic plasticity using electrophysiological recordings of basal transmission, paired pulse facilitation, and LTP and combined this with behavioral cognitive experiments addressing formation and retention of both contextual memory during aversive conditioning and spatial memory during spontaneous exploration. We demonstrate that hippocampal slices overexpressing PKMζ show enhanced basal transmission, suggesting a potential role of PKMζ in postsynaptic AMPAR trafficking. Moreover, the PKMζ-overexpressing slices augmented LTP and this effect was not abolished by protein-synthesis blockers, indicating that PKMζ induces enhanced LTP formation in a protein-synthesis-independent manner. In addition, we found selectively enhanced long-term memory for contextual but not cued fear memory, underlining the theory of the hippocampus' involvement in the contextual aspect of aversive reinforced tasks. Memory for spatial orientation during spontaneous exploration remained unaltered, suggesting that PKMζ may not affect the neural circuits underlying spontaneous tasks that are different from aversive tasks. In this study, using an overexpression strategy as opposed to an inhibitor-based approach, we demonstrate an important modulatory role of PKMζ in synaptic plasticity and selective memory processing. Most of the literature investigating protein kinase Mζ (PKMζ) used inhibitors with selectivity that has been called into question or conventional knock-out animal

  16. Priming in implicit memory tasks: prior study causes enhanced discriminability, not only bias.

    Science.gov (United States)

    Zeelenberg, René; Wagenmakers, Eric-Jan M; Raaijmakers, Jeroen G W

    2002-03-01

    R. Ratcliff and G. McKoon (1995, 1996, 1997; R. Ratcliff, D. Allbritton, & G. McKoon, 1997) have argued that repetition priming effects are solely due to bias. They showed that prior study of the target resulted in a benefit in a later implicit memory task. However, prior study of a stimulus similar to the target resulted in a cost. The present study, using a 2-alternative forced-choice procedure, investigated the effect of prior study in an unbiased condition: Both alternatives were studied prior to their presentation in an implicit memory task. Contrary to a pure bias interpretation of priming, consistent evidence was obtained in 3 implicit memory tasks (word fragment completion, auditory word identification, and picture identification) that performance was better when both alternatives were studied than when neither alternative was studied. These results show that prior study results in enhanced discriminability, not only bias.

  17. Enhancing memory and imagination improves problem solving among individuals with depression.

    Science.gov (United States)

    McFarland, Craig P; Primosch, Mark; Maxson, Chelsey M; Stewart, Brandon T

    2017-08-01

    Recent work has revealed links between memory, imagination, and problem solving, and suggests that increasing access to detailed memories can lead to improved imagination and problem-solving performance. Depression is often associated with overgeneral memory and imagination, along with problem-solving deficits. In this study, we tested the hypothesis that an interview designed to elicit detailed recollections would enhance imagination and problem solving among both depressed and nondepressed participants. In a within-subjects design, participants completed a control interview or an episodic specificity induction prior to completing memory, imagination, and problem-solving tasks. Results revealed that compared to the control interview, the episodic specificity induction fostered increased detail generation in memory and imagination and more relevant steps on the problem-solving task among depressed and nondepressed participants. This study builds on previous work by demonstrating that a brief interview can enhance problem solving among individuals with depression and supports the notion that episodic memory plays a key role in problem solving. It should be noted, however, that the results of the interview are relatively short-lived.

  18. Audiovisual semantic congruency during encoding enhances memory performance.

    Science.gov (United States)

    Heikkilä, Jenni; Alho, Kimmo; Hyvönen, Heidi; Tiippana, Kaisa

    2015-01-01

    Studies of memory and learning have usually focused on a single sensory modality, although human perception is multisensory in nature. In the present study, we investigated the effects of audiovisual encoding on later unisensory recognition memory performance. The participants were to memorize auditory or visual stimuli (sounds, pictures, spoken words, or written words), each of which co-occurred with either a semantically congruent stimulus, incongruent stimulus, or a neutral (non-semantic noise) stimulus in the other modality during encoding. Subsequent memory performance was overall better when the stimulus to be memorized was initially accompanied by a semantically congruent stimulus in the other modality than when it was accompanied by a neutral stimulus. These results suggest that semantically congruent multisensory experiences enhance encoding of both nonverbal and verbal materials, resulting in an improvement in their later recognition memory.

  19. Glucocorticoid enhancement of dorsolateral striatum-dependent habit memory requires concurrent noradrenergic activity.

    Science.gov (United States)

    Goodman, J; Leong, K-C; Packard, M G

    2015-12-17

    Previous findings indicate that post-training administration of glucocorticoid stress hormones can interact with the noradrenergic system to enhance consolidation of hippocampus- or amygdala-dependent cognitive/emotional memory. The present experiments were designed to extend these findings by examining the potential interaction of glucocorticoid and noradrenergic mechanisms in enhancement of dorsolateral striatum (DLS)-dependent habit memory. In experiment 1, different groups of adult male Long-Evans rats received training in two DLS-dependent memory tasks. In a cued water maze task, rats were released from various start points and were reinforced to approach a visibly cued escape platform. In a response-learning version of the water plus-maze task, animals were released from opposite starting positions and were reinforced to make a consistent egocentric body-turn to reach a hidden escape platform. Immediately post-training, rats received peripheral injections of the glucocorticoid corticosterone (1 or 3 mg/kg) or vehicle solution. In both tasks, corticosterone (3 mg/kg) enhanced DLS-dependent habit memory. In experiment 2, a separate group of animals received training in the response learning version of the water plus-maze task and were given peripheral post-training injections of corticosterone (3 mg/kg), the β-adrenoreceptor antagonist propranolol (3 mg/kg), corticosterone and propranolol concurrently, or control vehicle solution. Corticosterone injections again enhanced DLS-dependent memory, and this effect was blocked by concurrent administration of propranolol. Propranolol administration by itself (3 mg/kg) did not influence DLS-dependent memory. Taken together, the findings indicate an interaction between glucocorticoid and noradrenergic mechanisms in DLS-dependent habit memory. Propranolol administration may be useful in treating stress-related human psychopathologies associated with a dysfunctional DLS-dependent habit memory system. Copyright © 2015

  20. Stress enhances the consolidation of extinction memory in a predictive learning task

    Directory of Open Access Journals (Sweden)

    Tanja eHamacher-Dang

    2013-08-01

    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

  1. Studying frequency processing of the brain to enhance long-term memory and develop a human brain protocol.

    Science.gov (United States)

    Friedrich, Wernher; Du, Shengzhi; Balt, Karlien

    2015-01-01

    The temporal lobe in conjunction with the hippocampus is responsible for memory processing. The gamma wave is involved with this process. To develop a human brain protocol, a better understanding of the relationship between gamma and long-term memory is vital. A more comprehensive understanding of the human brain and specific analogue waves it uses will support the development of a human brain protocol. Fifty-eight participants aged between 6 and 60 years participated in long-term memory experiments. It is envisaged that the brain could be stimulated through binaural beats (sound frequency) at 40 Hz (gamma) to enhance long-term memory capacity. EEG recordings have been transformed to sound and then to an information standard, namely ASCII. Statistical analysis showed a proportional relationship between long-term memory and gamma activity. Results from EEG recordings indicate a pattern. The pattern was obtained through the de-codification of an EEG recording to sound and then to ASCII. Stimulation of gamma should enhance long term memory capacity. More research is required to unlock the human brains' protocol key. This key will enable the processing of information directly to and from human memory via gamma, the hippocampus and the temporal lobe.

  2. Enhanced emotional interference on working memory performance in adults with ADHD.

    Science.gov (United States)

    Marx, Ivo; Domes, Gregor; Havenstein, Carolin; Berger, Christoph; Schulze, Lars; Herpertz, Sabine C

    2011-09-01

    Subjects with attention-deficit/hyperactivity disorder (ADHD) suffer from both executive dysfunction and deficits in emotion regulation. However, up to now, there has been no research demonstrating a clear impact of emotional dysregulation on cognitive performance in subjects with ADHD. Male and female adults with ADHD (n=39) and gender- and IQ-matched control subjects (n=40) performed an emotional working memory task (n-back task). In the background of the task, we presented neutral and negative stimuli varied in emotional saliency (negative pictures with low saliency, negative pictures with high saliency), but subjects were instructed to ignore these pictures and to process the working memory task as quickly and as accurately as possible. Compared to control subjects, ADHD patients showed both a general working memory deficit and enhanced distractability by emotionally salient stimuli in terms of lower n-back performance accuracy. In particular, while controls showed impaired WM performance when presented with highly arousing negative background pictures, a comparable decrement was observed in the ADHD group already with lowly arousing pictures. Our results suggest that difficulties in suppressing attention towards emotionally laden stimuli might result from deficient executive control in ADHD.

  3. Vaginocervical stimulation enhances social recognition memory in rats via oxytocin release in the olfactory bulb.

    Science.gov (United States)

    Larrazolo-López, A; Kendrick, K M; Aburto-Arciniega, M; Arriaga-Avila, V; Morimoto, S; Frias, M; Guevara-Guzmán, R

    2008-03-27

    The ability of vaginocervical stimulation (VCS) to promote olfactory social recognition memory at different stages of the ovarian cycle was investigated in female rats. A juvenile social recognition paradigm was used and memory retention tested at 30 and 300 min after an adult was exposed to a juvenile during three 4-min trials. Results showed that an intact social recognition memory was present at 30 min in animals with or without VCS and at all stages of the estrus cycle. However, whereas no animals in any stage of the estrus cycle showed retention of the specific recognition memory at 300 min, those in the proestrus/estrus phase that received VCS 10 min before the trial started did. In vivo microdialysis studies showed that there was a significant release of oxytocin after VCS in the olfactory bulb during proestrus. There was also increased oxytocin immunoreactivity within the olfactory bulb after VCS in proestrus animals compared with diestrus ones. Furthermore, when animals received an infusion of an oxytocin antagonist directly into the olfactory bulb, or a systemic administration of alpha or beta noradrenaline-antagonists, they failed to show evidence for maintenance of a selective olfactory recognition memory at 300 min. Animals with vagus or pelvic nerve section also showed no memory retention when tested after 300 min. These results suggest that VCS releases oxytocin in the olfactory bulb to enhance the social recognition memory and that this may be due to modulatory actions on noradrenaline release. The vagus and pelvic nerves are responsible for carrying the information from the pelvic area to the CNS.

  4. Memory enhancement produced by post-training exposure to sucrose-conditioned cues [v1; ref status: indexed, http://f1000r.es/ur

    Directory of Open Access Journals (Sweden)

    Matthew R Holahan

    2013-01-01

    Full Text Available A number of aversive and appetitive unconditioned stimuli (such as shock and food are known to produce memory enhancement when they occur during the post-training period. Post-training exposure to conditioned aversive stimuli has also been shown to enhance memory consolidation processes. The present study shows for the first time that post-training exposure to conditioned stimuli previously paired with consumption of a sucrose solution also enhances memory consolidation. Male Long Evans rats were trained on a one-session conditioned cue preference (CCP task on a radial arm maze. Immediately or 2 hours after training, rats consumed a sucrose solution or were exposed to cues previously paired with consumption of sucrose or cues previously paired with water. Twenty-four hours later, the rats were tested for a CCP. Immediate, but not delayed, post-training consumption of sucrose enhanced memory for the CCP. Immediate, but not delayed, post-training exposure to cues previously paired with sucrose, but not with water, also enhanced CCP memory. The possibility that rewarding and aversive conditioned stimuli affect memory by a common physiological process is discussed.

  5. Motor Skills Enhance Procedural Memory Formation and Protect against Age-Related Decline.

    Science.gov (United States)

    Müller, Nils C J; Genzel, Lisa; Konrad, Boris N; Pawlowski, Marcel; Neville, David; Fernández, Guillén; Steiger, Axel; Dresler, Martin

    2016-01-01

    The ability to consolidate procedural memories declines with increasing age. Prior knowledge enhances learning and memory consolidation of novel but related information in various domains. Here, we present evidence that prior motor experience-in our case piano skills-increases procedural learning and has a protective effect against age-related decline for the consolidation of novel but related manual movements. In our main experiment, we tested 128 participants with a sequential finger-tapping motor task during two sessions 24 hours apart. We observed enhanced online learning speed and offline memory consolidation for piano players. Enhanced memory consolidation was driven by a strong effect in older participants, whereas younger participants did not benefit significantly from prior piano experience. In a follow up independent control experiment, this compensatory effect of piano experience was not visible after a brief offline period of 30 minutes, hence requiring an extended consolidation window potentially involving sleep. Through a further control experiment, we rejected the possibility that the decreased effect in younger participants was caused by training saturation. We discuss our results in the context of the neurobiological schema approach and suggest that prior experience has the potential to rescue memory consolidation from age-related cognitive decline.

  6. Repetition suppression and repetition enhancement underlie auditory memory-trace formation in the human brain: an MEG study.

    Science.gov (United States)

    Recasens, Marc; Leung, Sumie; Grimm, Sabine; Nowak, Rafal; Escera, Carles

    2015-03-01

    The formation of echoic memory traces has traditionally been inferred from the enhanced responses to its deviations. The mismatch negativity (MMN), an auditory event-related potential (ERP) elicited between 100 and 250ms after sound deviation is an indirect index of regularity encoding that reflects a memory-based comparison process. Recently, repetition positivity (RP) has been described as a candidate ERP correlate of direct memory trace formation. RP consists of repetition suppression and enhancement effects occurring in different auditory components between 50 and 250ms after sound onset. However, the neuronal generators engaged in the encoding of repeated stimulus features have received little interest. This study intends to investigate the neuronal sources underlying the formation and strengthening of new memory traces by employing a roving-standard paradigm, where trains of different frequencies and different lengths are presented randomly. Source generators of repetition enhanced (RE) and suppressed (RS) activity were modeled using magnetoencephalography (MEG) in healthy subjects. Our results show that, in line with RP findings, N1m (~95-150ms) activity is suppressed with stimulus repetition. In addition, we observed the emergence of a sustained field (~230-270ms) that showed RE. Source analysis revealed neuronal generators of RS and RE located in both auditory and non-auditory areas, like the medial parietal cortex and frontal areas. The different timing and location of neural generators involved in RS and RE points to the existence of functionally separated mechanisms devoted to acoustic memory-trace formation in different auditory processing stages of the human brain. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Beta2- and beta3-adrenoceptors activate glucose uptake in chick astrocytes by distinct mechanisms: a mechanism for memory enhancement?

    Science.gov (United States)

    Hutchinson, Dana S; Summers, Roger J; Gibbs, Marie E

    2007-11-01

    Isoprenaline, acting at beta-adrenoceptors (ARs), enhances memory formation in single trial discriminated avoidance learning in day-old chicks by mechanisms involving alterations in glucose and glycogen metabolism. Earlier studies of memory consolidation in chicks indicated that beta3-ARs enhanced memory by increasing glucose uptake, whereas beta2-ARs enhance memory by increasing glycogenolysis. This study examines the ability of beta-ARs to increase glucose uptake in chick forebrain astrocytes. The beta-AR agonist isoprenaline increased glucose uptake in a concentration-dependent manner, as did insulin. Glucose uptake was increased by the beta2-AR agonist zinterol and the beta3-AR agonist CL316243, but not by the beta1-AR agonist RO363. In chick astrocytes, reverse transcription-polymerase chain reaction studies showed that beta1-, beta2-, and beta3-AR mRNA were present, whereas radioligand-binding studies showed the presence of only beta2- and beta3-ARs. beta-AR or insulin-mediated glucose uptake was inhibited by phosphatidylinositol-3 kinase and protein kinase C inhibitors, suggesting a possible interaction between the beta-AR and insulin pathways. However beta2- and beta3-ARs increase glucose uptake by two different mechanisms: beta2-ARs via a Gs-cAMP-protein kinase A-dependent pathway, while beta3-ARs via interactions with Gi. These results indicate that activation of beta2- and beta3-ARs causes glucose uptake in chick astrocytes by distinct mechanisms, which may be relevant for memory enhancement.

  8. Heterozygous Che-1 KO mice show deficiencies in object recognition memory persistence.

    Science.gov (United States)

    Zalcman, Gisela; Corbi, Nicoletta; Di Certo, Maria Grazia; Mattei, Elisabetta; Federman, Noel; Romano, Arturo

    2016-10-06

    Transcriptional regulation is a key process in the formation of long-term memories. Che-1 is a protein involved in the regulation of gene transcription that has recently been proved to bind the transcription factor NF-κB, which is known to be involved in many memory-related molecular events. This evidence prompted us to investigate the putative role of Che-1 in memory processes. For this study we newly generated a line of Che-1(+/-) heterozygous mice. Che-1 homozygous KO mouse is lethal during development, but Che-1(+/-) heterozygous mouse is normal in its general anatomical and physiological characteristics. We analyzed the behavioral characteristic and memory performance of Che-1(+/-) mice in two NF-κB dependent types of memory. We found that Che-1(+/-) mice show similar locomotor activity and thigmotactic behavior than wild type (WT) mice in an open field. In a similar way, no differences were found in anxiety-like behavior between Che-1(+/-) and WT mice in an elevated plus maze as well as in fear response in a contextual fear conditioning (CFC) and object exploration in a novel object recognition (NOR) task. No differences were found between WT and Che-1(+/-) mice performance in CFC training and when tested at 24h or 7days after training. Similar performance was found between groups in NOR task, both in training and 24h testing performance. However, we found that object recognition memory persistence at 7days was impaired in Che-1(+/-) heterozygous mice. This is the first evidence showing that Che-1 is involved in memory processes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Music-Based Memory Enhancement in Alzheimer’s Disease: Promise and Limitations

    Science.gov (United States)

    Simmons-Stern, Nicholas R.; Deason, Rebecca G.; Brandler, Brian J.; Frustace, Bruno S.; O’Connor, Maureen K.; Ally, Brandon A.; Budson, Andrew E.

    2012-01-01

    In a previous study (Simmons-Stern, Budson, & Ally 2010), we found that patients with Alzheimer’s disease (AD) better recognized visually presented lyrics when the lyrics were also sung rather than spoken at encoding. The present study sought to further investigate the effects of music on memory in patients with AD by making the content of the song lyrics relevant for the daily life of an older adult and by examining how musical encoding alters several different aspects of episodic memory. Patients with AD and healthy older adults studied visually presented novel song lyrics related to instrumental activities of daily living (IADL) that were accompanied by either a sung or a spoken recording. Overall, participants performed better on a memory test of general lyric content for lyrics that were studied sung as compared to spoken. However, on a memory test of specific lyric content, participants performed equally well for sung and spoken lyrics. We interpret these results in terms of a dual-process model of recognition memory such that the general content questions represent a familiarity-based representation that is preferentially sensitive to enhancement via music, while the specific content questions represent a recollection-based representation unaided by musical encoding. Additionally, in a test of basic recognition memory for the audio stimuli, patients with AD demonstrated equal discrimination for sung and spoken stimuli. We propose that the perceptual distinctiveness of musical stimuli enhanced metamemorial awareness in AD patients via a non-selective distinctiveness heuristic, thereby reducing false recognition while at the same time reducing true recognition and eliminating the mnemonic benefit of music. These results are discussed in the context of potential music-based memory enhancement interventions for the care of patients with AD. PMID:23000133

  10. Methylprednisolone as a memory enhancer in rats: Effects on aversive memory, long-term potentiation and calcium influx.

    Science.gov (United States)

    de Vargas, Liane da Silva; Gonçalves, Rithiele; Lara, Marcus Vinícius S; Costa-Ferro, Zaquer S M; Salamoni, Simone Denise; Domingues, Michelle Flores; Piovesan, Angela Regina; de Assis, Dênis Reis; Vinade, Lucia; Corrado, Alexandre P; Alves-Do-Prado, Wilson; Correia-de-Sá, Paulo; da Costa, Jaderson Costa; Izquierdo, Ivan; Dal Belo, Cháriston A; Mello-Carpes, Pâmela B

    2017-09-01

    It is well recognized that stress or glucocorticoids hormones treatment can modulate memory performance in both directions, either impairing or enhancing it. Despite the high number of studies aiming at explaining the effects of glucocorticoids on memory, this has not yet been completely elucidated. Here, we demonstrate that a low daily dose of methylprednisolone (MP, 5mg/kg, i.p.) administered for 10-days favors aversive memory persistence in adult rats, without any effect on the exploring behavior, locomotor activity, anxiety levels and pain perception. Enhanced performance on the inhibitory avoidance task was correlated with long-term potentiation (LTP), a phenomenon that was strengthen in hippocampal slices of rats injected with MP (5mg/kg) during 10days. Additionally, in vitro incubation with MP (30-300µM) concentration-dependently increased intracellular [Ca 2+ ] i in cultured hippocampal neurons depolarized by KCl (35mM). In conclusion, a low daily dose of MP for 10days may promote aversive memory persistence in rats. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Post-training amphetamine administration enhances memory consolidation in appetitive Pavlovian conditioning: Implications for drug addiction.

    Science.gov (United States)

    Simon, Nicholas W; Setlow, Barry

    2006-11-01

    It has been suggested that some of the addictive potential of psychostimulant drugs of abuse such as amphetamine may result from their ability to enhance memory for drug-related experiences through actions on memory consolidation. This experiment examined whether amphetamine can specifically enhance consolidation of memory for a Pavlovian association between a neutral conditioned stimulus (CS-a light) and a rewarding unconditioned stimulus (US-food), as Pavlovian conditioning of this sort plays a major role in drug addiction. Male Long-Evans rats were given six training sessions consisting of 8 CS presentations followed by delivery of the food into a recessed food cup. After the 1st, 3rd, and 5th session, rats received subcutaneous injections of amphetamine (1.0 or 2.0 mg/kg) or saline vehicle immediately following training. Conditioned responding was assessed using the percentage of time rats spent in the food cup during the CS relative to a pre-CS baseline period. Both amphetamine-treated groups showed significantly more selective conditioned responding than saline controls. In a control experiment, there were no differences among groups given saline, 1.0 or 2.0 mg/kg amphetamine 2 h post-training, suggesting that immediate post-training amphetamine enhanced performance specifically through actions on memory consolidation rather than through non-mnemonic processes. This procedure modeled Pavlovian learning involved in drug addiction, in which the emotional valence of a drug reward is transferred to neutral drug-predictive stimuli such as drug paraphernalia. These data suggest that amphetamine may contribute to its addictive potential through actions specifically on memory consolidation.

  12. Glucose enhancement of event-related potentials associated with episodic memory and attention.

    Science.gov (United States)

    Brown, Louise A; Riby, Leigh M

    2013-04-30

    Previous studies have reported that increasing glycaemia by a glucose-containing drink enhances memory functioning. The aim of the present study was to extend this literature by examining the effects of glucose on episodic memory as well as attention processes, and to investigate associated event-related potential (ERP) markers. Fifteen minutes after treatment (25 g glucose or placebo drink), 35 participants performed an old/new recognition memory task and a Stroop colour naming task. Consistent with previous research, when controlling for glucose regulation, cognitive facilitation was observed behaviourally for verbal memory, but there was also a trend towards attentional facilitation. Furthermore, across both domains, it was the most demanding task conditions that exhibited glucose sensitivity. In support of the behavioural results, the analysis of ERPs across treatment groups revealed an enhanced left-parietal old/new effect related to recollection, and also suggested modulation of attentional processes. The results suggest that glucose may facilitate attention as well as memory.

  13. Diminishing-cues retrieval practice: A memory-enhancing technique that works when regular testing doesn't.

    Science.gov (United States)

    Fiechter, Joshua L; Benjamin, Aaron S

    2017-08-28

    Retrieval practice has been shown to be a highly effective tool for enhancing memory, a fact that has led to major changes to educational practice and technology. However, when initial learning is poor, initial retrieval practice is unlikely to be successful and long-term benefits of retrieval practice are compromised or nonexistent. Here, we investigate the benefit of a scaffolded retrieval technique called diminishing-cues retrieval practice (Finley, Benjamin, Hays, Bjork, & Kornell, Journal of Memory and Language, 64, 289-298, 2011). Under learning conditions that favored a strong testing effect, diminishing cues and standard retrieval practice both enhanced memory performance relative to restudy. Critically, under learning conditions where standard retrieval practice was not helpful, diminishing cues enhanced memory performance substantially. These experiments demonstrate that diminishing-cues retrieval practice can widen the range of conditions under which testing can benefit memory, and so can serve as a model for the broader application of testing-based techniques for enhancing learning.

  14. Fatty-acid binding proteins modulate sleep and enhance long-term memory consolidation in Drosophila.

    Directory of Open Access Journals (Sweden)

    Jason R Gerstner

    2011-01-01

    Full Text Available Sleep is thought to be important for memory consolidation, since sleep deprivation has been shown to interfere with memory processing. However, the effects of augmenting sleep on memory formation are not well known, and testing the role of sleep in memory enhancement has been limited to pharmacological and behavioral approaches. Here we test the effect of overexpressing the brain-type fatty acid binding protein (Fabp7 on sleep and long-term memory (LTM formation in Drosophila melanogaster. Transgenic flies carrying the murine Fabp7 or the Drosophila homologue dFabp had reduced baseline sleep but normal LTM, while Fabp induction produced increases in both net sleep and LTM. We also define a post-training consolidation "window" that is sufficient for the observed Fabp-mediated memory enhancement. Since Fabp overexpression increases consolidated daytime sleep bouts, these data support a role for longer naps in improving memory and provide a novel role for lipid-binding proteins in regulating memory consolidation concurrently with changes in behavioral state.

  15. ADRA2B deletion variant selectively predicts stress-induced enhancement of long-term memory in females.

    Science.gov (United States)

    Zoladz, Phillip R; Kalchik, Andrea E; Hoffman, Mackenzie M; Aufdenkampe, Rachael L; Lyle, Sarah M; Peters, David M; Brown, Callie M; Cadle, Chelsea E; Scharf, Amanda R; Dailey, Alison M; Wolters, Nicholas E; Talbot, Jeffery N; Rorabaugh, Boyd R

    2014-10-01

    Clarifying the mechanisms that underlie stress-induced alterations of learning and memory may lend important insight into susceptibility factors governing the development of stress-related psychological disorders, such as post-traumatic stress disorder (PTSD). Previous work has shown that carriers of the ADRA2B Glu(301)-Glu(303) deletion variant exhibit enhanced emotional memory, greater amygdala responses to emotional stimuli and greater intrusiveness of traumatic memories. We speculated that carriers of this deletion variant might also be more vulnerable to stress-induced enhancements of long-term memory, which would implicate the variant as a possible susceptibility factor for traumatic memory formation. One hundred and twenty participants (72 males, 48 females) submerged their hand in ice cold (stress) or warm (no stress) water for 3min. Immediately afterwards, they studied a list of 42 words varying in emotional valence and arousal and then completed an immediate free recall test. Twenty-four hours later, participants' memory for the word list was examined via free recall and recognition assessments. Stressed participants exhibiting greater heart rate responses to the stressor had enhanced recall on the 24-h assessment. Importantly, this enhancement was independent of the emotional nature of the learned information. In contrast to previous work, we did not observe a general enhancement of memory for emotional information in ADRA2B deletion carriers. However, stressed female ADRA2B deletion carriers, particularly those exhibiting greater heart rate responses to the stressor, did demonstrate greater recognition memory than all other groups. Collectively, these findings implicate autonomic mechanisms in the pre-learning stress-induced enhancement of long-term memory and suggest that the ADRA2B deletion variant may selectively predict stress effects on memory in females. Such findings lend important insight into the physiological mechanisms underlying stress

  16. Memory-enhancing effects of Cuscuta japonica Choisy via enhancement of adult hippocampal neurogenesis in mice.

    Science.gov (United States)

    Moon, Minho; Jeong, Hyun Uk; Choi, Jin Gyu; Jeon, Seong Gak; Song, Eun Ji; Hong, Seon-Pyo; Oh, Myung Sook

    2016-09-15

    It is generally accepted that functional and structural changes within the hippocampus are involved in learning and memory and that adult neurogenesis in this region may modulate cognition. The extract of Cuscuta japonica Choisy (CJ) is a well-known traditional Chinese herbal medicine that has been used since ancient times as a rejuvenation remedy. The systemic effects of this herb are widely known and can be applied for the treatment of a number of physiological diseases, but there is a lack of evidence describing its effects on brain function. Thus, the present study investigated whether CJ would enhance memory function and/or increase hippocampal neurogenesis using mice orally administered with CJ water extract or vehicle for 21days. Performance on the novel object recognition and passive avoidance tests revealed that treatment with CJ dose-dependently improved the cognitive function of mice. Additionally, CJ increased the Ki-67-positive proliferating cells and the number of doublecortin-stained neuroblasts in the dentate gyrus (DG) of the hippocampus, and double labeling with 5-bromo-2-deoxyuridine and neuronal specific nuclear protein showed that CJ increased the number of mature neurons in the DG. Finally, CJ resulted in the upregulated expression of neurogenic differentiation factor, which is essential for the maturation and differentiation of granule cells in the hippocampus. Taken together, the present findings indicate that CJ stimulated neuronal cell proliferation, differentiation, and maturation, which are all processes associated with neurogenesis. Additionally, these findings suggest that CJ may improve learning and memory via the enhancement of adult hippocampal neurogenesis. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Getting more from visual working memory: Retro-cues enhance retrieval and protect from visual interference.

    Science.gov (United States)

    Souza, Alessandra S; Rerko, Laura; Oberauer, Klaus

    2016-06-01

    Visual working memory (VWM) has a limited capacity. This limitation can be mitigated by the use of focused attention: if attention is drawn to the relevant working memory content before test, performance improves (the so-called retro-cue benefit). This study tests 2 explanations of the retro-cue benefit: (a) Focused attention protects memory representations from interference by visual input at test, and (b) focusing attention enhances retrieval. Across 6 experiments using color recognition and color reproduction tasks, we varied the amount of color interference at test, and the delay between a retrieval cue (i.e., the retro-cue) and the memory test. Retro-cue benefits were larger when the memory test introduced interfering visual stimuli, showing that the retro-cue effect is in part because of protection from visual interference. However, when visual interference was held constant, retro-cue benefits were still obtained whenever the retro-cue enabled retrieval of an object from VWM but delayed response selection. Our results show that accessible information in VWM might be lost in the processes of testing memory because of visual interference and incomplete retrieval. This is not an inevitable state of affairs, though: Focused attention can be used to get the most out of VWM. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  18. Caffeine in floral nectar enhances a pollinator’s memory of reward

    Science.gov (United States)

    Wright, G. A.; Baker, D. D.; Palmer, M. J.; Stabler, D.; Mustard, J. A.; Power, E. F.; Borland, A. M.; Stevenson, P. C.

    2015-01-01

    Plant defence compounds occur in floral nectar, but their ecological role is not well-understood. We provide the first evidence that plant compounds pharmacologically alter pollinator behaviour by enhancing their memory of reward. Honeybees rewarded with caffeine, which occurs naturally in nectar of Coffea and Citrus species, were three times more likely to remember a learned floral scent than those rewarded with sucrose alone. Caffeine potentiated responses of mushroom body neurons involved in olfactory learning and memory by acting as an adenosine receptor antagonist. Caffeine concentrations in nectar never exceeded the bees’ bitter taste threshold, implying that pollinators impose selection for nectar that is pharmacologically active but not repellent. By using a drug to enhance memories of reward, plants secure pollinator fidelity and improve reproductive success. PMID:23471406

  19. Emotion strengthens high-priority memory traces but weakens low-priority memory traces.

    Science.gov (United States)

    Sakaki, Michiko; Fryer, Kellie; Mather, Mara

    2014-02-01

    When people encounter emotional events, their memory for those events is typically enhanced. But it has been unclear how emotionally arousing events influence memory for preceding information. Does emotional arousal induce retrograde amnesia or retrograde enhancement? The current study revealed that this depends on the top-down goal relevance of the preceding information. Across three studies, we found that emotional arousal induced by one image facilitated memory for the preceding neutral item when people prioritized that neutral item. In contrast, an emotionally arousing image impaired memory for the preceding neutral item when people did not prioritize that neutral item. Emotional arousal elicited by both negative and positive pictures showed this pattern of enhancing or impairing memory for the preceding stimulus depending on its priority. These results indicate that emotional arousal amplifies the effects of top-down priority in memory formation.

  20. A single bout of resistance exercise can enhance episodic memory performance.

    Science.gov (United States)

    Weinberg, Lisa; Hasni, Anita; Shinohara, Minoru; Duarte, Audrey

    2014-11-01

    Acute aerobic exercise can be beneficial to episodic memory. This benefit may occur because exercise produces a similar physiological response as physical stressors. When administered during consolidation, acute stress, both physical and psychological, consistently enhances episodic memory, particularly memory for emotional materials. Here we investigated whether a single bout of resistance exercise performed during consolidation can produce episodic memory benefits 48 h later. We used a one-leg knee extension/flexion task for the resistance exercise. To assess the physiological response to the exercise, we measured salivary alpha amylase (a biomarker of central norepinephrine), heart rate, and blood pressure. To test emotional episodic memory, we used a remember-know recognition memory paradigm with equal numbers of positive, negative, and neutral IAPS images as stimuli. The group that performed the exercise, the active group, had higher overall recognition accuracy than the group that did not exercise, the passive group. We found a robust effect of valence across groups, with better performance on emotional items as compared to neutral items and no difference between positive and negative items. This effect changed based on the physiological response to the exercise. Within the active group, participants with a high physiological response to the exercise were impaired for neutral items as compared to participants with a low physiological response to the exercise. Our results demonstrate that a single bout of resistance exercise performed during consolidation can enhance episodic memory and that the effect of valence on memory depends on the physiological response to the exercise. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Grapheme-color synesthesia can enhance immediate memory without disrupting the encoding of relational cues.

    Science.gov (United States)

    Gibson, Bradley S; Radvansky, Gabriel A; Johnson, Ann C; McNerney, M Windy

    2012-12-01

    Previous evidence has suggested that grapheme-color synesthesia can enhance memory for words, but little is known about how these photisms cue retrieval. Often, the encoding of specific features of individual words can disrupt the encoding of ordered relations between words, resulting in an overall decrease in recall accuracy. Here we show that the photisms arising from grapheme-color synesthesia do not function like these item-specific cues. The influences of high and low word frequency on the encoding of ordered relations and the accuracy of immediate free recall were compared across a group of 10 synesthetes and 48 nonsynesthetes. The main findings of Experiment 1 showed that the experience of synesthesia had no adverse effect on the encoding of ordered relations (as measured by input-output correspondence); furthermore, it enhanced recall accuracy in a strictly additive fashion across the two word frequency conditions. Experiment 2 corroborated these findings by showing that the synesthetes only outperformed the nonsynesthetes when the materials involved words and letters, not when they involved digits and spatial locations. Altogether, the present findings suggest that synesthesia can boost immediate memory performance without disrupting the encoding of ordered relations.

  2. Neurofeedback training of EEG alpha rhythm enhances episodic and working memory.

    Science.gov (United States)

    Hsueh, Jen-Jui; Chen, Tzu-Shan; Chen, Jia-Jin; Shaw, Fu-Zen

    2016-07-01

    Neurofeedback training (NFT) of the alpha rhythm has been used for several decades but is still controversial in regards to its trainability and effects on working memory. Alpha rhythm of the frontoparietal region are associated with either the intelligence or memory of healthy subjects and are also related to pathological states. In this study, alpha NFT effects on memory performances were explored. Fifty healthy participants were recruited and randomly assigned into a group receiving a 8-12-Hz amplitude (Alpha) or a group receiving a random 4-Hz amplitude from the range of 7 to 20 Hz (Ctrl). Three NFT sessions per week were conducted for 4 weeks. Working memory was assessed by both a backward digit span task and an operation span task, and episodic memory was assessed using a word pair task. Four questionnaires were used to assess anxiety, depression, insomnia, and cognitive function. The Ctrl group had no change in alpha amplitude and duration. In contrast, the Alpha group showed a progressive significant increase in the alpha amplitude and total alpha duration of the frontoparietal region. Accuracies of both working and episodic memories were significantly improved in a large proportion of participants of the Alpha group, particularly for those with remarkable alpha-amplitude increases. Scores of four questionnaires fell in a normal range before and after NFT. The current study provided supporting evidence for alpha trainability within a small session number compared with that of therapy. The findings suggested the enhancement of working and episodic memory through alpha NFT. Hum Brain Mapp 37:2662-2675, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Discrete Serotonin Systems Mediate Memory Enhancement and Escape Latencies after Unpredicted Aversive Experience in Drosophila Place Memory

    Directory of Open Access Journals (Sweden)

    Divya Sitaraman

    2017-12-01

    Full Text Available Feedback mechanisms in operant learning are critical for animals to increase reward or reduce punishment. However, not all conditions have a behavior that can readily resolve an event. Animals must then try out different behaviors to better their situation through outcome learning. This form of learning allows for novel solutions and with positive experience can lead to unexpected behavioral routines. Learned helplessness, as a type of outcome learning, manifests in part as increases in escape latency in the face of repeated unpredicted shocks. Little is known about the mechanisms of outcome learning. When fruit fly Drosophilamelanogaster are exposed to unpredicted high temperatures in a place learning paradigm, flies both increase escape latencies and have a higher memory when given control of a place/temperature contingency. Here we describe discrete serotonin neuronal circuits that mediate aversive reinforcement, escape latencies, and memory levels after place learning in the presence and absence of unexpected aversive events. The results show that two features of learned helplessness depend on the same modulatory system as aversive reinforcement. Moreover, changes in aversive reinforcement and escape latency depend on local neural circuit modulation, while memory enhancement requires larger modulation of multiple behavioral control circuits.

  4. Declarative memory.

    Science.gov (United States)

    Riedel, Wim J; Blokland, Arjan

    2015-01-01

    Declarative Memory consists of memory for events (episodic memory) and facts (semantic memory). Methods to test declarative memory are key in investigating effects of potential cognition-enhancing substances--medicinal drugs or nutrients. A number of cognitive performance tests assessing declarative episodic memory tapping verbal learning, logical memory, pattern recognition memory, and paired associates learning are described. These tests have been used as outcome variables in 34 studies in humans that have been described in the literature in the past 10 years. Also, the use of episodic tests in animal research is discussed also in relation to the drug effects in these tasks. The results show that nutritional supplementation of polyunsaturated fatty acids has been investigated most abundantly and, in a number of cases, but not all, show indications of positive effects on declarative memory, more so in elderly than in young subjects. Studies investigating effects of registered anti-Alzheimer drugs, cholinesterase inhibitors in mild cognitive impairment, show positive and negative effects on declarative memory. Studies mainly carried out in healthy volunteers investigating the effects of acute dopamine stimulation indicate enhanced memory consolidation as manifested specifically by better delayed recall, especially at time points long after learning and more so when drug is administered after learning and if word lists are longer. The animal studies reveal a different picture with respect to the effects of different drugs on memory performance. This suggests that at least for episodic memory tasks, the translational value is rather poor. For the human studies, detailed parameters of the compositions of word lists for declarative memory tests are discussed and it is concluded that tailored adaptations of tests to fit the hypothesis under study, rather than "off-the-shelf" use of existing tests, are recommended.

  5. Visual Working Memory Enhances the Neural Response to Matching Visual Input.

    Science.gov (United States)

    Gayet, Surya; Guggenmos, Matthias; Christophel, Thomas B; Haynes, John-Dylan; Paffen, Chris L E; Van der Stigchel, Stefan; Sterzer, Philipp

    2017-07-12

    Visual working memory (VWM) is used to maintain visual information available for subsequent goal-directed behavior. The content of VWM has been shown to affect the behavioral response to concurrent visual input, suggesting that visual representations originating from VWM and from sensory input draw upon a shared neural substrate (i.e., a sensory recruitment stance on VWM storage). Here, we hypothesized that visual information maintained in VWM would enhance the neural response to concurrent visual input that matches the content of VWM. To test this hypothesis, we measured fMRI BOLD responses to task-irrelevant stimuli acquired from 15 human participants (three males) performing a concurrent delayed match-to-sample task. In this task, observers were sequentially presented with two shape stimuli and a retro-cue indicating which of the two shapes should be memorized for subsequent recognition. During the retention interval, a task-irrelevant shape (the probe) was briefly presented in the peripheral visual field, which could either match or mismatch the shape category of the memorized stimulus. We show that this probe stimulus elicited a stronger BOLD response, and allowed for increased shape-classification performance, when it matched rather than mismatched the concurrently memorized content, despite identical visual stimulation. Our results demonstrate that VWM enhances the neural response to concurrent visual input in a content-specific way. This finding is consistent with the view that neural populations involved in sensory processing are recruited for VWM storage, and it provides a common explanation for a plethora of behavioral studies in which VWM-matching visual input elicits a stronger behavioral and perceptual response. SIGNIFICANCE STATEMENT Humans heavily rely on visual information to interact with their environment and frequently must memorize such information for later use. Visual working memory allows for maintaining such visual information in the mind

  6. Neural correlates of retrieval-based memory enhancement: an fMRI study of the testing effect.

    Science.gov (United States)

    Wing, Erik A; Marsh, Elizabeth J; Cabeza, Roberto

    2013-10-01

    Restudying material is a common method for learning new information, but not necessarily an effective one. Research on the testing effect shows that practice involving retrieval from memory can facilitate later memory in contrast to passive restudy. Despite extensive behavioral work, the brain processes that make retrieval an effective learning strategy remain unclear. In the present experiment, we explored how initially retrieving items affected memory a day later as compared to a condition involving traditional restudy. In contrast to restudy, initial testing that contributed to future memory success was associated with engagement of several regions including the anterior hippocampus, lateral temporal cortices, and medial prefrontal cortex (PFC). Additionally, testing enhanced hippocampal connectivity with ventrolateral PFC and midline regions. These findings indicate that the testing effect may be contingent on processes that are typically thought to support memory success at encoding (e.g. relational binding, selection and elaboration of semantically-related information) in addition to those more often associated with retrieval (e.g. memory search). © 2013 Elsevier Ltd. All rights reserved.

  7. Reward acts on the pFC to enhance distractor resistance of working memory representations.

    Science.gov (United States)

    Fallon, Sean James; Cools, Roshan

    2014-12-01

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

  8. Juvenile obesity enhances emotional memory and amygdala plasticity through glucocorticoids.

    Science.gov (United States)

    Boitard, Chloé; Maroun, Mouna; Tantot, Frédéric; Cavaroc, Amandine; Sauvant, Julie; Marchand, Alain; Layé, Sophie; Capuron, Lucile; Darnaudery, Muriel; Castanon, Nathalie; Coutureau, Etienne; Vouimba, Rose-Marie; Ferreira, Guillaume

    2015-03-04

    In addition to metabolic and cardiovascular disorders, obesity is associated with adverse cognitive and emotional outcomes. Its growing prevalence during adolescence is particularly alarming since recent evidence indicates that obesity can affect hippocampal function during this developmental period. Adolescence is a decisive period for maturation of the amygdala and the hypothalamic-pituitary-adrenal (HPA) stress axis, both required for lifelong cognitive and emotional processing. However, little data are available on the impact of obesity during adolescence on amygdala function. Herein, we therefore evaluate in rats whether juvenile high-fat diet (HFD)-induced obesity alters amygdala-dependent emotional memory and whether it depends on HPA axis deregulation. Exposure to HFD from weaning to adulthood, i.e., covering adolescence, enhances long-term emotional memories as assessed by odor-malaise and tone-shock associations. Juvenile HFD also enhances emotion-induced neuronal activation of the basolateral complex of the amygdala (BLA), which correlates with protracted plasma corticosterone release. HFD exposure restricted to adulthood does not modify all these parameters, indicating adolescence is a vulnerable period to the effects of HFD-induced obesity. Finally, exaggerated emotional memory and BLA synaptic plasticity after juvenile HFD are alleviated by a glucocorticoid receptor antagonist. Altogether, our results demonstrate that juvenile HFD alters HPA axis reactivity leading to an enhancement of amygdala-dependent synaptic and memory processes. Adolescence represents a period of increased susceptibility to the effects of diet-induced obesity on amygdala function. Copyright © 2015 the authors 0270-6474/15/354092-12$15.00/0.

  9. Behavioural memory reconsolidation of food and fear memories.

    Science.gov (United States)

    Flavell, Charlotte R; Barber, David J; Lee, Jonathan L C

    2011-10-18

    The reactivation of a memory through retrieval can render it subject to disruption or modification through the process of memory reconsolidation. In both humans and rodents, briefly reactivating a fear memory results in effective erasure by subsequent extinction training. Here we show that a similar strategy is equally effective in the disruption of appetitive pavlovian cue-food memories. However, systemic administration of the NMDA receptor partial agonist D-cycloserine, under the same behavioural conditions, did not potentiate appetitive memory extinction, suggesting that reactivation does not enhance subsequent extinction learning. To confirm that reactivation followed by extinction reflects a behavioural analogue of memory reconsolidation, we show that prevention of contextual fear memory reactivation by the L-type voltage-gated calcium channel blocker nimodipine interferes with the amnestic outcome. Therefore, the reconsolidation process can be manipulated behaviourally to disrupt both aversive and appetitive memories. © 2011 Macmillan Publishers Limited. All rights reserved.

  10. Enhancing effects of chronic lithium on memory in the rat.

    Science.gov (United States)

    Tsaltas, Eleftheria; Kontis, Dimitrios; Boulougouris, Vasileios; Papakosta, Vasiliki-Maria; Giannou, Haralambos; Poulopoulou, Cornelia; Soldatos, Constantine

    2007-02-12

    In spite of recent enrichment of neurochemical and behavioural data establishing a neuroprotective role for lithium, its primary effects on cognitive functioning remain ambiguous. This study examines chronic lithium effects on spatial working memory and long-term retention. In three discrete experiments, rats subjected to 30 daily intraperitoneal injections (2mmol/kg) of lithium (lithium groups: serum lithium=0.5+/-0.4mEq/l, 12h post-injection) or saline (controls) were trained in 0-s delay T-maze alternation and then tested in 30-, 45- and 60-s delay alternation (Experiments 1, 2, 3, respectively). Animals from Experiment 1 were further tested in one-trial step-through passive avoidance under mild shock parameters (0.5mA, 1s). Retention was assessed 6h later. Daily lithium or saline injections continued throughout behavioural testing. Lithium animals were indistinguishable from controls during 0-delay alternation baseline (Experiments 1-3, accuracy>88%) but showed significantly higher accuracy than controls at 30- and 45-s delays (93% versus 85% and 92% versus 82%, Experiments 1 and 2, respectively). At 60-s delay (Experiment 3) this beneficial effect of lithium was no longer apparent (lithium and control accuracy=78%). In Experiment 4, the shock used did not support 6-h passive avoidance retention in controls, whereas lithium animals showed significant step-through latency increases. Chronic lithium enhanced spatial working memory and promoted long-term retention of a weak aversive contingency. The results suggest that lithium may have potential as a cognitive enhancer.

  11. Is the enhancement of memory due to reward driven by value or salience?

    Science.gov (United States)

    Madan, Christopher R; Spetch, Marcia L

    2012-02-01

    Past research using two levels of reward has shown that the higher-value items are remembered better than lower-value items and this enhancement is assumed to be driven by an effect of reward value. In the present study, multiple levels of reward were used to test the influence of reward salience on memory. Using a value-learning procedure, words were associated with reward values, and then memory for these words was later tested with free recall. Critically, multiple reward levels were used, allowing us to test two specific hypotheses whereby rewards can influence memory: (a) higher value items are remembered better than lower value items (reward value hypothesis), and (b) highest and lowest value items are remembered best and intermediate-value items are remembered worst (following a U-shaped relationship between value and memory; reward salience hypothesis). In two experiments we observed a U-shaped relationship between reward value and memory, supporting the notion that memory is enhanced due to reward salience, and not purely through reward value. Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Glucocorticoids interact with the noradrenergic arousal system in the nucleus accumbens shell to enhance memory consolidation of both appetitive and aversive taste learning.

    Science.gov (United States)

    Wichmann, Romy; Fornari, Raquel V; Roozendaal, Benno

    2012-09-01

    It is well established that glucocorticoid hormones strengthen the consolidation of long-term memory of emotionally arousing experiences but have little effect on memory of low-arousing experiences. Although both positive and negative emotionally arousing events tend to be well remembered, studies investigating the neural mechanism underlying glucocorticoid-induced memory enhancement focused primarily on negatively motivated training experiences. In the present study we show an involvement of glucocorticoids within the nucleus accumbens (NAc) in enhancing memory consolidation of both an appetitive and aversive form of taste learning. The specific glucocorticoid receptor (GR) agonist RU 28362 (1 or 3ng) administered bilaterally into the NAc shell, but not core, of male Sprague-Dawley rats immediately after an appetitive saccharin drinking experience dose-dependently enhanced 24-h retention of the safe taste, resulting in a facilitated attenuation of neophobia. Similarly, GR agonist infusions given into the NAc shell immediately after pairing of the saccharin taste with a malaise-inducing agent enhanced memory of this negative experience, resulting in an intensified conditioned aversion. Importantly, a suppression of noradrenergic activity within the NAc shell with the β-adrenoceptor antagonist propranolol blocked the facilitating effect of a concurrently administered GR agonist on memory consolidation in both the appetitive and aversive learning task. Thus, these findings indicate that GR activation interacts with the noradrenergic arousal system within the NAc to enhance memory consolidation of emotionally arousing training experiences regardless of valence. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Glucose enhancement of event-related potentials associated with episodic memory and attention

    OpenAIRE

    Brown, Louise; Riby, Leigh

    2013-01-01

    Previous studies have reported that increasing glycaemia by a glucose-containing drink enhances memory functioning. The aim of the present study was to extend this literature by examining the effects of glucose on episodic memory as well as attention processes, and to investigate associated event-related potential (ERP) markers. Fifteen minutes after treatment (25 g glucose or placebo drink), 35 participants performed an old/new recognition memory task and a Stroop colour naming task. Consist...

  14. Significantly enhanced memory effect in metallic glass by multistep training

    Science.gov (United States)

    Li, M. X.; Luo, P.; Sun, Y. T.; Wen, P.; Bai, H. Y.; Liu, Y. H.; Wang, W. H.

    2017-11-01

    The state of metastable equilibrium glass can carry an imprint of the past and exhibit memory effect. As a hallmark of glassy dynamics, memory effect can affect glassy behavior as it evolves further upon time. Even though the physical picture of the memory effect has been well studied, it is unclear whether a glass can recall as many pieces of information as possible, and if so, how the glass will accordingly behave. We report that by fractionizing temperature interval, inserting multistep aging protocols, and optimizing the time of each temperature step, i.e., by imposing a multistep "training" on a prototypical P d40N i10C u30P20 metallic glass, the memory of the trained glass can be significantly strengthened, marked by a pronounced augment in potential energy. These findings provide a new guide for regulating the energy state of glass by enhancing the nonequilibrium behaviors of the memory effect and offer an opportunity to develop a clearer physical picture of glassy dynamics.

  15. Blocking the eIF2α kinase (PKR) enhances positive and negative forms of cortex-dependent taste memory.

    Science.gov (United States)

    Stern, Elad; Chinnakkaruppan, Adaikkan; David, Orit; Sonenberg, Nahum; Rosenblum, Kobi

    2013-02-06

    Age-associated memory deterioration (and the decline in ability to acquire new information) is one of the major diseases of our era. Cognitive enhancement can be achieved by using psycho-stimulants, such as caffeine or nicotine, but very little is known about drugs that can enhance the consolidation phase of memories in the cortex, the brain structure considered to store, at least partially, long-term memories. We used cortex-dependent taste-learning paradigms to test the hypothesis that pharmacological manipulation of the translation initiation eIF2α, which plays a role in hippocampus-dependent memory, can enhance positive or negative forms of taste memories. We found that dephosphorylation (Ser51) of eIF2α, specifically in the cortex, is both correlated with and necessary for normal memory consolidation. To reduce eIF2α phosphorylation and improve memory consolidation, we pharmacologically inhibited one of the eIF2α kinases, PKR, which is known to be involved in brain aging and Alzheimer's disease. Systemic or local microinjection of PKR inhibitor to the gustatory cortex enhanced both positive and negative forms of taste memory in rats and mice. Our results provide clear evidence that PKR plays a major role in cortex-dependent memory consolidation and, therefore, that pharmacological inhibition of PKR is a potential target for drugs to enhance cognition.

  16. Infants with complex congenital heart diseases show poor short-term memory in the mobile paradigm at 3 months of age.

    Science.gov (United States)

    Chen, Chao-Ying; Harrison, Tondi; Heathcock, Jill

    2015-08-01

    The purpose of this study was to examine learning, short-term memory and general development including cognitive, motor, and language domains in infants with Complex Congenital Heart Defects (CCDH). Ten infants with CCHD (4 males, 6 females) and 14 infants with typical development (TD) were examined at 3 months of age. The mobile paradigm, where an infant's leg is tethered to an overhead mobile, was used to evaluate learning and short-term memory. The Bayley Scales of Infant Development 3rd edition (Bayley-III) was used to evaluate general development in cognitive, motor, and language domains. Infants with CCHD and infants with TD both showed learning with significant increase in kicking rate (pshort-term memory (p=0.017) in the mobile paradigm. There were no differences on cognitive, motor, and language development between infants with CCHD and infants with TD on the Bayley-III. Early assessment is necessary to guide targeted treatment in infants with CCHD. One-time assessment may fail to detect potential cognitive impairments during early infancy in infants with CCHD. Supportive intervention programs for infants with CCHD that focuses on enhancing short-term memory are recommended. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Estradiol enhances retention but not organization of hippocampus-dependent memory in intact male mice.

    Science.gov (United States)

    Al Abed, Alice Shaam; Sellami, Azza; Brayda-Bruno, Laurent; Lamothe, Valérie; Noguès, Xavier; Potier, Mylène; Bennetau-Pelissero, Catherine; Marighetto, Aline

    2016-07-01

    Because estrogens have mostly been studied in gonadectomized females, effects of chronic exposure to environmental estrogens in the general population are underestimated. Estrogens can enhance hippocampus-dependent memory through the modulation of information storage. However, declarative memory, the hippocampus-dependent memory of facts and events, demands more than abilities to retain information. Specifically, memory of repetitive events of everyday life such as "where I parked" requires abilities to organize/update memories to prevent proactive interference from similar memories of previous "parking events". Whether such organizational processes are estrogen-sensitive is unknown. We here studied, in intact young and aged adult mice, drinking-water (1μM) estradiol effects on both retention and organizational components of hippocampus-dependent memory, using a radial-maze task of everyday-like memory. Demand on retention vs organization was manipulated by varying the time-interval separating repetitions of similar events. Estradiol increased performance in young and aged mice under minimized organizational demand, but failed to improve the age-associated memory impairment and diminished performance in young mice under high organizational demand. In fact, estradiol prolonged mnemonic retention of successive events without improving organization abilities, hence resulted in more proactive interference from irrelevant memories. c-Fos imaging of testing-induced brain activations showed that the deterioration of young memory was associated with dentate gyrus dysconnectivity, reminiscent of that seen in aged mice. Our findings support the view that estradiol is promnesic but also reveal that such property can paradoxically impair memory. These findings have important outcomes regarding health issues relative to the impact of environmental estrogens in the general population. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Gift from statistical learning: Visual statistical learning enhances memory for sequence elements and impairs memory for items that disrupt regularities.

    Science.gov (United States)

    Otsuka, Sachio; Saiki, Jun

    2016-02-01

    Prior studies have shown that visual statistical learning (VSL) enhances familiarity (a type of memory) of sequences. How do statistical regularities influence the processing of each triplet element and inserted distractors that disrupt the regularity? Given that increased attention to triplets induced by VSL and inhibition of unattended triplets, we predicted that VSL would promote memory for each triplet constituent, and degrade memory for inserted stimuli. Across the first two experiments, we found that objects from structured sequences were more likely to be remembered than objects from random sequences, and that letters (Experiment 1) or objects (Experiment 2) inserted into structured sequences were less likely to be remembered than those inserted into random sequences. In the subsequent two experiments, we examined an alternative account for our results, whereby the difference in memory for inserted items between structured and random conditions is due to individuation of items within random sequences. Our findings replicated even when control letters (Experiment 3A) or objects (Experiment 3B) were presented before or after, rather than inserted into, random sequences. Our findings suggest that statistical learning enhances memory for each item in a regular set and impairs memory for items that disrupt the regularity. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Enhancement of synchronized activity between hippocampal CA1 neurons during initial storage of associative fear memory.

    Science.gov (United States)

    Liu, Yu-Zhang; Wang, Yao; Shen, Weida; Wang, Zhiru

    2017-08-01

    Learning and memory storage requires neuronal plasticity induced in the hippocampus and other related brain areas, and this process is thought to rely on synchronized activity in neural networks. We used paired whole-cell recording in vivo to examine the synchronized activity that was induced in hippocampal CA1 neurons by associative fear learning. We found that both membrane potential synchronization and spike synchronization of CA1 neurons could be transiently enhanced after task learning, as observed on day 1 but not day 5. On day 1 after learning, CA1 neurons showed a decrease in firing threshold and rise times of suprathreshold membrane potential changes as well as an increase in spontaneous firing rates, possibly contributing to the enhancement of spike synchronization. The transient enhancement of CA1 neuronal synchronization may play important roles in the induction of neuronal plasticity for initial storage and consolidation of associative memory. The hippocampus is critical for memory acquisition and consolidation. This function requires activity- and experience-induced neuronal plasticity. It is known that neuronal plasticity is largely dependent on synchronized activity. As has been well characterized, repetitive correlated activity of presynaptic and postsynaptic neurons can lead to long-term modifications at their synapses. Studies on network activity have also suggested that memory processing in the hippocampus may involve learning-induced changes of neuronal synchronization, as observed in vivo between hippocampal CA3 and CA1 networks as well as between the rhinal cortex and the hippocampus. However, further investigation of learning-induced synchronized activity in the hippocampus is needed for a full understanding of hippocampal memory processing. In this study, by performing paired whole-cell recording in vivo on CA1 pyramidal cells (PCs) in anaesthetized adult rats, we examined CA1 neuronal synchronization before and after associative fear

  20. Stress enhances reconsolidation of declarative memory.

    Science.gov (United States)

    Bos, Marieke G N; Schuijer, Jantien; Lodestijn, Fleur; Beckers, Tom; Kindt, Merel

    2014-08-01

    Retrieval of negative emotional memories is often accompanied by the experience of stress. Upon retrieval, a memory trace can temporarily return into a labile state, where it is vulnerable to change. An unresolved question is whether post-retrieval stress may affect the strength of declarative memory in humans by modulating the reconsolidation process. Here, we tested in two experiments whether post-reactivation stress may affect the strength of declarative memory in humans. In both experiments, participants were instructed to learn neutral, positive and negative words. Approximately 24h later, participants received a reminder of the word list followed by exposure to the social evaluative cold pressor task (reactivation/stress group, nexp1=20; nexp2=18) or control task (reactivation/no-stress group, nexp1=23; nexp2=18). An additional control group was solely exposed to the stress task, without memory reactivation (no-reactivation/stress group, nexp1=23; nexp2=21). The next day, memory performance was tested using a free recall and a recognition task. In the first experiment we showed that participants in the reactivation/stress group recalled more words than participants in the reactivation/no-stress and no-reactivation/stress group, irrespective of valence of the word stimuli. Furthermore, participants in the reactivation/stress group made more false recognition errors. In the second experiment we replicated our observations on the free recall task for a new set of word stimuli, but we did not find any differences in false recognition. The current findings indicate that post-reactivation stress can improve declarative memory performance by modulating the process of reconsolidation. This finding contributes to our understanding why some memories are more persistent than others. Copyright © 2014. Published by Elsevier Ltd.

  1. Musical Mnemonics Enhance Verbal Memory in Typically Developing Children

    Directory of Open Access Journals (Sweden)

    David Knott

    2018-05-01

    Full Text Available The purpose of this study was to compare the effects of musical mnemonics vs. spoken word in training verbal memory in children. A randomized control trial of typically-developing 9–11 year old children was conducted using the Rey Auditory Verbal Learning Test (RAVLT, a test measuring a participant's ability to recall a list of 15 words over multiple exposures. Members of the group who listened to words sung to them recalled an average of 20% more words after listening to and recalling an interference list than members of the control group who listened to the same words spoken. This difference persisted, though slightly smaller (17% when participants recalled words after a 15-min waiting period. Additionally, group participants who listened to words sung demonstrated a higher incidence of words recalled in correct serial order. Key findings were all statistically significant at the P < 0.05 level. Enhanced serial order recall points to the musical pitch/rhythm structure enhancing sequence memory as a potential mnemonic mechanism. No significant differences were found in serial position effects between groups. The findings suggest that musical mnemonic training may be more effective than rehearsal with spoken words in verbal memory learning tasks in 9–11 year olds.

  2. The Benefit of Attention-to-Memory Depends on the Interplay of Memory Capacity and Memory Load

    Science.gov (United States)

    Lim, Sung-Joo; Wöstmann, Malte; Geweke, Frederik; Obleser, Jonas

    2018-01-01

    Humans can be cued to attend to an item in memory, which facilitates and enhances the perceptual precision in recalling this item. Here, we demonstrate that this facilitating effect of attention-to-memory hinges on the overall degree of memory load. The benefit an individual draws from attention-to-memory depends on her overall working memory performance, measured as sensitivity (d′) in a retroactive cue (retro-cue) pitch discrimination task. While listeners maintained 2, 4, or 6 auditory syllables in memory, we provided valid or neutral retro-cues to direct listeners’ attention to one, to-be-probed syllable in memory. Participants’ overall memory performance (i.e., perceptual sensitivity d′) was relatively unaffected by the presence of valid retro-cues across memory loads. However, a more fine-grained analysis using psychophysical modeling shows that valid retro-cues elicited faster pitch-change judgments and improved perceptual precision. Importantly, as memory load increased, listeners’ overall working memory performance correlated with inter-individual differences in the degree to which precision improved (r = 0.39, p = 0.029). Under high load, individuals with low working memory profited least from attention-to-memory. Our results demonstrate that retrospective attention enhances perceptual precision of attended items in memory but listeners’ optimal use of informative cues depends on their overall memory abilities. PMID:29520246

  3. The Benefit of Attention-to-Memory Depends on the Interplay of Memory Capacity and Memory Load

    Directory of Open Access Journals (Sweden)

    Sung-Joo Lim

    2018-02-01

    Full Text Available Humans can be cued to attend to an item in memory, which facilitates and enhances the perceptual precision in recalling this item. Here, we demonstrate that this facilitating effect of attention-to-memory hinges on the overall degree of memory load. The benefit an individual draws from attention-to-memory depends on her overall working memory performance, measured as sensitivity (d′ in a retroactive cue (retro-cue pitch discrimination task. While listeners maintained 2, 4, or 6 auditory syllables in memory, we provided valid or neutral retro-cues to direct listeners’ attention to one, to-be-probed syllable in memory. Participants’ overall memory performance (i.e., perceptual sensitivity d′ was relatively unaffected by the presence of valid retro-cues across memory loads. However, a more fine-grained analysis using psychophysical modeling shows that valid retro-cues elicited faster pitch-change judgments and improved perceptual precision. Importantly, as memory load increased, listeners’ overall working memory performance correlated with inter-individual differences in the degree to which precision improved (r = 0.39, p = 0.029. Under high load, individuals with low working memory profited least from attention-to-memory. Our results demonstrate that retrospective attention enhances perceptual precision of attended items in memory but listeners’ optimal use of informative cues depends on their overall memory abilities.

  4. Post-learning stress enhances long-term memory and differentially influences memory in females depending on menstrual stage.

    Science.gov (United States)

    Zoladz, Phillip R; Peters, David M; Cadle, Chelsea E; Kalchik, Andrea E; Aufdenkampe, Rachael L; Dailey, Alison M; Brown, Callie M; Scharf, Amanda R; Earley, McKenna B; Knippen, Courtney L; Rorabaugh, Boyd R

    2015-09-01

    Most work has shown that post-learning stress enhances long-term memory; however, there have been recent inconsistencies in this literature. The purpose of the present study was to examine further the effects of post-learning stress on long-term memory and to explore any sex differences that may exist. Male and female participants learned a list of 42 words that varied in emotional valence and arousal level. Following encoding, participants completed a free recall assessment and then submerged their hand into a bath of ice cold (stress) or lukewarm (no stress) water for 3 min. The next day, participants were given free recall and recognition tests. Stressed participants recalled more words than non-stressed participants 24h after learning. Stress also enhanced female participants' recall of arousing words when they were in the follicular, but not luteal, phase. These findings replicate previous work examining post-learning stress effects on memory and implicate the involvement of sex-related hormones in such effects. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Sustained frontal midline theta enhancements during effortful listening track working memory demands.

    Science.gov (United States)

    Wisniewski, Matthew G; Iyer, Nandini; Thompson, Eric R; Simpson, Brian D

    2017-11-27

    Recent studies demonstrate that frontal midline theta power (4-8 Hz) enhancements in the electroencephalogram (EEG) relate to effortful listening. It has been proposed that these enhancements reflect working memory demands. Here, the need to retain auditory information in working memory was manipulated in a 2-interval 2-alternative forced-choice delayed pitch discrimination task ("Which interval contained the higher pitch?"). On each trial, two square wave stimuli differing in pitch at an individual's ∼70.7% correct threshold were separated by a 3-second ISI. In a 'Roving' condition, the lowest pitch stimulus was randomly selected on each trial (uniform distribution from 840 to 1160 Hz). In a 'Fixed' condition, the lowest pitch was always 979 Hz. Critically, the 'Fixed' condition allowed one to know the correct response immediately following the first stimulus (e.g., if the first stimulus is 979 Hz, the second must be higher). In contrast, the 'Roving' condition required retention of the first tone for comparison to the second. Frontal midline theta enhancements during the ISI were only observed for the 'Roving' condition. Alpha (8-13 Hz) enhancements were apparent during the ISI, but did not differ significantly between conditions. Since conditions were matched for accuracy at threshold, results suggest that frontal midline theta enhancements will not always accompany difficult listening. Mixed results in the literature regarding frontal midline theta enhancements may be related to differences between tasks in regards to working memory demands. Alpha enhancements may reflect task general effortful listening processes. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Glucose enhancement of memory is modulated by trait anxiety in healthy adolescent males

    OpenAIRE

    Smith, Michael; Hii, Hilary; Foster, Jonathan; van Eekelen, Anke

    2011-01-01

    Glucose administration is associated with memory enhancement in healthy young individuals under conditions of divided attention at encoding. While the specific neurocognitive mechanisms underlying this ‘glucose memory facilitation effect’ are currently uncertain, it is thought that individual differences in glucoregulatory efficiency may alter an individual’s sensitivity to the glucose memory facilitation effect. In the present study, we sought to investigate whether basal hypothalamic–pituit...

  7. Enhanced visual memory during hypnosis as mediated by hypnotic responsiveness and cognitive strategies.

    Science.gov (United States)

    Crawford, H J; Allen, S N

    1983-12-01

    To investigate the hypothesis that hypnosis has an enhancing effect on imagery processing, as mediated by hypnotic responsiveness and cognitive strategies, four experiments compared performance of low and high, or low, medium, and high, hypnotically responsive subjects in waking and hypnosis conditions on a successive visual memory discrimination task that required detecting differences between successively presented picture pairs in which one member of the pair was slightly altered. Consistently, hypnotically responsive individuals showed enhanced performance during hypnosis, whereas nonresponsive ones did not. Hypnotic responsiveness correlated .52 (p less than .001) with enhanced performance during hypnosis, but it was uncorrelated with waking performance (Experiment 3). Reaction time was not affected by hypnosis, although high hypnotizables were faster than lows in their responses (Experiments 1 and 2). Subjects reported enhanced imagery vividness on the self-report Vividness of Visual Imagery Questionnaire during hypnosis. The differential effect between lows and highs was in the anticipated direction but not significant (Experiments 1 and 2). As anticipated, hypnosis had no significant effect on a discrimination task that required determining whether there were differences between pairs of simultaneously presented pictures. Two cognitive strategies that appeared to mediate visual memory performance were reported: (a) detail strategy, which involved the memorization and rehearsal of individual details for memory, and (b) holistic strategy, which involved looking at and remembering the whole picture with accompanying imagery. Both lows and highs reported similar predominantly detail-oriented strategies during waking; only highs shifted to a significantly more holistic strategy during hypnosis. These findings suggest that high hypnotizables have a greater capacity for cognitive flexibility (Batting, 1979) than do lows. Results are discussed in terms of several

  8. The role of eye fixation in memory enhancement under stress - An eye tracking study.

    Science.gov (United States)

    Herten, Nadja; Otto, Tobias; Wolf, Oliver T

    2017-04-01

    In a stressful situation, attention is shifted to potentially relevant stimuli. Recent studies from our laboratory revealed that participants stressed perform superior in a recognition task involving objects of the stressful episode. In order to characterize the role of a stress induced alteration in visual exploration, the present study investigated whether participants experiencing a laboratory social stress situation differ in their fixation from participants of a control group. Further, we aimed at shedding light on the relation of fixation behaviour with obtained memory measures. We randomly assigned 32 male and 31 female participants to a control or a stress condition consisting of the Trier Social Stress Test (TSST), a public speaking paradigm causing social evaluative threat. In an established 'friendly' control condition (f-TSST) participants talk to a friendly committee. During both conditions, the committee members used ten office items (central objects) while another ten objects were present without being used (peripheral objects). Participants wore eye tracking glasses recording their fixations. On the next day, participants performed free recall and recognition tasks involving the objects present the day before. Stressed participants showed enhanced memory for central objects, accompanied by longer fixation times and larger fixation amounts on these objects. Contrasting this, fixation towards the committee faces showed the reversed pattern; here, control participants exhibited longer fixations. Fixation indices and memory measures were, however, not correlated with each other. Psychosocial stress is associated with altered fixation behaviour. Longer fixation on objects related to the stressful situation may reflect enhanced encoding, whereas diminished face fixation suggests gaze avoidance of aversive, socially threatening stimuli. Modified visual exploration should be considered in future stress research, in particular when focussing on memory for a

  9. Gaming is related to enhanced working memory performance and task-related cortical activity.

    Science.gov (United States)

    Moisala, M; Salmela, V; Hietajärvi, L; Carlson, S; Vuontela, V; Lonka, K; Hakkarainen, K; Salmela-Aro, K; Alho, K

    2017-01-15

    Gaming experience has been suggested to lead to performance enhancements in a wide variety of working memory tasks. Previous studies have, however, mostly focused on adult expert gamers and have not included measurements of both behavioral performance and brain activity. In the current study, 167 adolescents and young adults (aged 13-24 years) with different amounts of gaming experience performed an n-back working memory task with vowels, with the sensory modality of the vowel stream switching between audition and vision at random intervals. We studied the relationship between self-reported daily gaming activity, working memory (n-back) task performance and related brain activity measured using functional magnetic resonance imaging (fMRI). The results revealed that the extent of daily gaming activity was related to enhancements in both performance accuracy and speed during the most demanding (2-back) level of the working memory task. This improved working memory performance was accompanied by enhanced recruitment of a fronto-parietal cortical network, especially the dorsolateral prefrontal cortex. In contrast, during the less demanding (1-back) level of the task, gaming was associated with decreased activity in the same cortical regions. Our results suggest that a greater degree of daily gaming experience is associated with better working memory functioning and task difficulty-dependent modulation in fronto-parietal brain activity already in adolescence and even when non-expert gamers are studied. The direction of causality within this association cannot be inferred with certainty due to the correlational nature of the current study. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Divided Attention Can Enhance Memory Encoding: The Attentional Boost Effect in Implicit Memory

    Science.gov (United States)

    Spataro, Pietro; Mulligan, Neil W.; Rossi-Arnaud, Clelia

    2013-01-01

    Distraction during encoding has long been known to disrupt later memory performance. Contrary to this long-standing result, we show that detecting an infrequent target in a dual-task paradigm actually improves memory encoding for a concurrently presented word, above and beyond the performance reached in the full-attention condition. This absolute…

  11. Post-Training Intrahippocampal Inhibition of Class I Histone Deacetylases Enhances Long-Term Object-Location Memory

    Science.gov (United States)

    Hawk, Joshua D.; Florian, Cedrick; Abel, Ted

    2011-01-01

    Long-term memory formation involves covalent modification of the histone proteins that package DNA. Reducing histone acetylation by mutating histone acetyltransferases impairs long-term memory, and enhancing histone acetylation by inhibiting histone deacetylases (HDACs) improves long-term memory. Previous studies using HDAC inhibitors to enhance…

  12. Negative emotion enhances mnemonic precision and subjective feelings of remembering in visual long-term memory.

    Science.gov (United States)

    Xie, Weizhen; Zhang, Weiwei

    2017-09-01

    Negative emotion sometimes enhances memory (higher accuracy and/or vividness, e.g., flashbulb memories). The present study investigates whether it is the qualitative (precision) or quantitative (the probability of successful retrieval) aspect of memory that drives these effects. In a visual long-term memory task, observers memorized colors (Experiment 1a) or orientations (Experiment 1b) of sequentially presented everyday objects under negative, neutral, or positive emotions induced with International Affective Picture System images. In a subsequent test phase, observers reconstructed objects' colors or orientations using the method of adjustment. We found that mnemonic precision was enhanced under the negative condition relative to the neutral and positive conditions. In contrast, the probability of successful retrieval was comparable across the emotion conditions. Furthermore, the boost in memory precision was associated with elevated subjective feelings of remembering (vividness and confidence) and metacognitive sensitivity in Experiment 2. Altogether, these findings suggest a novel precision-based account for emotional memories. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Memory-guided saccades show effect of a perceptual illusion whereas visually guided saccades do not.

    Science.gov (United States)

    Massendari, Delphine; Lisi, Matteo; Collins, Thérèse; Cavanagh, Patrick

    2018-01-01

    The double-drift stimulus (a drifting Gabor with orthogonal internal motion) generates a large discrepancy between its physical and perceived path. Surprisingly, saccades directed to the double-drift stimulus land along the physical, and not perceived, path (Lisi M, Cavanagh P. Curr Biol 25: 2535-2540, 2015). We asked whether memory-guided saccades exhibited the same dissociation from perception. Participants were asked to keep their gaze centered on a fixation dot while the double-drift stimulus moved back and forth on a linear path in the periphery. The offset of the fixation was the go signal to make a saccade to the target. In the visually guided saccade condition, the Gabor kept moving on its trajectory after the go signal but was removed once the saccade began. In the memory conditions, the Gabor disappeared before or at the same time as the go-signal (0- to 1,000-ms delay) and participants made a saccade to its remembered location. The results showed that visually guided saccades again targeted the physical rather than the perceived location. However, memory saccades, even with 0-ms delay, had landing positions shifted toward the perceived location. Our result shows that memory- and visually guided saccades are based on different spatial information. NEW & NOTEWORTHY We compared the effect of a perceptual illusion on two types of saccades, visually guided vs. memory-guided saccades, and found that whereas visually guided saccades were almost unaffected by the perceptual illusion, memory-guided saccades exhibited a strong effect of the illusion. Our result is the first evidence in the literature to show that visually and memory-guided saccades use different spatial representations.

  14. Activation of Gαq Signaling Enhances Memory Consolidation and Slows Cognitive Decline.

    Science.gov (United States)

    Arey, Rachel N; Stein, Geneva M; Kaletsky, Rachel; Kauffman, Amanda; Murphy, Coleen T

    2018-05-02

    Perhaps the most devastating decline with age is the loss of memory. Therefore, identifying mechanisms to restore memory function with age is critical. Using C. elegans associative learning and memory assays, we identified a gain-of-function G αq signaling pathway mutant that forms a long-term (cAMP response element binding protein [CREB]-dependent) memory following one conditioned stimulus-unconditioned stimulus (CS-US) pairing, which usually requires seven CS-US pairings. Increased CREB activity in AIM interneurons reduces the threshold for memory consolidation through transcription of a set of previously identified "long-term memory" genes. Enhanced G αq signaling in the AWC sensory neuron is both necessary and sufficient for improved memory and increased AIM CREB activity, and activation of G αq specifically in aged animals rescues the ability to form memory. Activation of G αq in AWC sensory neurons non-cell autonomously induces consolidation after one CS-US pairing, enabling both cognitive function maintenance with age and restoration of memory function in animals with impaired memory performance without decreased longevity. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Adult-onset hypothyroidism enhances fear memory and upregulates mineralocorticoid and glucocorticoid receptors in the amygdala.

    Science.gov (United States)

    Montero-Pedrazuela, Ana; Fernández-Lamo, Iván; Alieva, María; Pereda-Pérez, Inmaculada; Venero, César; Guadaño-Ferraz, Ana

    2011-01-01

    Hypothyroidism is the most common hormonal disease in adults, which is frequently accompanied by learning and memory impairments and emotional disorders. However, the deleterious effects of thyroid hormones deficiency on emotional memory are poorly understood and often underestimated. To evaluate the consequences of hypothyroidism on emotional learning and memory, we have performed a classical Pavlovian fear conditioning paradigm in euthyroid and adult-thyroidectomized Wistar rats. In this experimental model, learning acquisition was not impaired, fear memory was enhanced, memory extinction was delayed and spontaneous recovery of fear memory was exacerbated in hypothyroid rats. The potentiation of emotional memory under hypothyroidism was associated with an increase of corticosterone release after fear conditioning and with higher expression of glucocorticoid and mineralocorticoid receptors in the lateral and basolateral nuclei of the amygdala, nuclei that are critically involved in the circuitry of fear memory. Our results demonstrate for the first time that adult-onset hypothyroidism potentiates fear memory and also increases vulnerability to develop emotional memories. Furthermore, our findings suggest that enhanced corticosterone signaling in the amygdala is involved in the pathophysiological mechanisms of fear memory potentiation. Therefore, we recommend evaluating whether inappropriate regulation of fear in patients with post-traumatic stress and other mental disorders is associated with abnormal levels of thyroid hormones, especially those patients refractory to treatment.

  16. Adult-onset hypothyroidism enhances fear memory and upregulates mineralocorticoid and glucocorticoid receptors in the amygdala.

    Directory of Open Access Journals (Sweden)

    Ana Montero-Pedrazuela

    Full Text Available Hypothyroidism is the most common hormonal disease in adults, which is frequently accompanied by learning and memory impairments and emotional disorders. However, the deleterious effects of thyroid hormones deficiency on emotional memory are poorly understood and often underestimated. To evaluate the consequences of hypothyroidism on emotional learning and memory, we have performed a classical Pavlovian fear conditioning paradigm in euthyroid and adult-thyroidectomized Wistar rats. In this experimental model, learning acquisition was not impaired, fear memory was enhanced, memory extinction was delayed and spontaneous recovery of fear memory was exacerbated in hypothyroid rats. The potentiation of emotional memory under hypothyroidism was associated with an increase of corticosterone release after fear conditioning and with higher expression of glucocorticoid and mineralocorticoid receptors in the lateral and basolateral nuclei of the amygdala, nuclei that are critically involved in the circuitry of fear memory. Our results demonstrate for the first time that adult-onset hypothyroidism potentiates fear memory and also increases vulnerability to develop emotional memories. Furthermore, our findings suggest that enhanced corticosterone signaling in the amygdala is involved in the pathophysiological mechanisms of fear memory potentiation. Therefore, we recommend evaluating whether inappropriate regulation of fear in patients with post-traumatic stress and other mental disorders is associated with abnormal levels of thyroid hormones, especially those patients refractory to treatment.

  17. Adult-Onset Hypothyroidism Enhances Fear Memory and Upregulates Mineralocorticoid and Glucocorticoid Receptors in the Amygdala

    Science.gov (United States)

    Montero-Pedrazuela, Ana; Fernández-Lamo, Iván; Alieva, María; Pereda-Pérez, Inmaculada; Venero, César; Guadaño-Ferraz, Ana

    2011-01-01

    Hypothyroidism is the most common hormonal disease in adults, which is frequently accompanied by learning and memory impairments and emotional disorders. However, the deleterious effects of thyroid hormones deficiency on emotional memory are poorly understood and often underestimated. To evaluate the consequences of hypothyroidism on emotional learning and memory, we have performed a classical Pavlovian fear conditioning paradigm in euthyroid and adult-thyroidectomized Wistar rats. In this experimental model, learning acquisition was not impaired, fear memory was enhanced, memory extinction was delayed and spontaneous recovery of fear memory was exacerbated in hypothyroid rats. The potentiation of emotional memory under hypothyroidism was associated with an increase of corticosterone release after fear conditioning and with higher expression of glucocorticoid and mineralocorticoid receptors in the lateral and basolateral nuclei of the amygdala, nuclei that are critically involved in the circuitry of fear memory. Our results demonstrate for the first time that adult-onset hypothyroidism potentiates fear memory and also increases vulnerability to develop emotional memories. Furthermore, our findings suggest that enhanced corticosterone signaling in the amygdala is involved in the pathophysiological mechanisms of fear memory potentiation. Therefore, we recommend evaluating whether inappropriate regulation of fear in patients with post-traumatic stress and other mental disorders is associated with abnormal levels of thyroid hormones, especially those patients refractory to treatment. PMID:22039511

  18. Brains of verbal memory specialists show anatomical differences in language, memory and visual systems.

    Science.gov (United States)

    Hartzell, James F; Davis, Ben; Melcher, David; Miceli, Gabriele; Jovicich, Jorge; Nath, Tanmay; Singh, Nandini Chatterjee; Hasson, Uri

    2016-05-01

    We studied a group of verbal memory specialists to determine whether intensive oral text memory is associated with structural features of hippocampal and lateral-temporal regions implicated in language processing. Professional Vedic Sanskrit Pandits in India train from childhood for around 10years in an ancient, formalized tradition of oral Sanskrit text memorization and recitation, mastering the exact pronunciation and invariant content of multiple 40,000-100,000 word oral texts. We conducted structural analysis of gray matter density, cortical thickness, local gyrification, and white matter structure, relative to matched controls. We found massive gray matter density and cortical thickness increases in Pandit brains in language, memory and visual systems, including i) bilateral lateral temporal cortices and ii) the anterior cingulate cortex and the hippocampus, regions associated with long and short-term memory. Differences in hippocampal morphometry matched those previously documented for expert spatial navigators and individuals with good verbal working memory. The findings provide unique insight into the brain organization implementing formalized oral knowledge systems. Copyright © 2015. Published by Elsevier Inc.

  19. Examination of mechanisms underlying enhanced memory performance in action video game players: a pilot study.

    Science.gov (United States)

    Li, Xianchun; Cheng, Xiaojun; Li, Jiaying; Pan, Yafeng; Hu, Yi; Ku, Yixuan

    2015-01-01

    Previous studies have shown enhanced memory performance resulting from extensive action video game playing. The mechanisms underlying the cognitive benefit were investigated in the current study. We presented two types of retro-cues, with variable intervals to memory array (Task 1) or test array (Task 2), during the retention interval in a change detection task. In Task 1, action video game players demonstrated steady performance while non-action video game players showed decreased performance as cues occurred later, indicating their performance difference increased as the cue-to-memory-array intervals became longer. In Task 2, both participant groups increased their performance at similar rates as cues presented later, implying the performance difference in two groups were irrespective of the test-array-to-cue intervals. These findings suggested that memory benefit from game plays is not attributable to the higher ability of overcoming interference from the test array, but to the interactions between the two processes of protection from decay and resistance from interference, or from alternative hypotheses. Implications for future studies were discussed.

  20. Picturing survival memories: enhanced memory after fitness-relevant processing occurs for verbal and visual stimuli.

    Science.gov (United States)

    Otgaar, Henry; Smeets, Tom; van Bergen, Saskia

    2010-01-01

    Recent studies have shown that processing words according to a survival scenario leads to superior retention relative to control conditions. Here, we examined whether a survival recall advantage could be elicited by using pictures. Furthermore, in Experiment 1, we were interested in whether survival processing also results in improved memory for details. Undergraduates rated the relevance of pictures in a survival, moving, or pleasantness scenario and were subsequently given a surprise free recall test. We found that survival processing yielded superior retention. We also found that distortions occurred more often in the survival condition than in the pleasantness condition. In Experiment 2, we directly compared the survival recall effect between pictures and words. A comparable survival recall advantage was found for pictures and words. The present findings support the idea that memory is enhanced by processing information in terms of fitness value, yet at the same time, the present results suggest that this may increase the risk for memory distortions.

  1. Glucose enhancement of human memory: a comprehensive research review of the glucose memory facilitation effect.

    Science.gov (United States)

    Smith, Michael A; Riby, Leigh M; Eekelen, J Anke M van; Foster, Jonathan K

    2011-01-01

    The brain relies upon glucose as its primary fuel. In recent years, a rich literature has developed from both human and animal studies indicating that increases in circulating blood glucose can facilitate cognitive functioning. This phenomenon has been termed the 'glucose memory facilitation effect'. The purpose of this review is to discuss a number of salient studies which have investigated the influence of glucose ingestion on neurocognitive performance in individuals with (a) compromised neurocognitive capacity, as well as (b) normally functioning individuals (with a focus on research conducted with human participants). The proposed neurocognitive mechanisms purported to underlie the modulatory effect of glucose on neurocognitive performance will also be considered. Many theories have focussed upon the hippocampus, given that this brain region is heavily implicated in learning and memory. Further, it will be suggested that glucose is a possible mechanism underlying the phenomenon that enhanced memory performance is typically observed for emotionally laden stimuli. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Retrospective attention enhances visual working memory in the young but not the old: an ERP study

    Science.gov (United States)

    Duarte, Audrey; Hearons, Patricia; Jiang, Yashu; Delvin, Mary Courtney; Newsome, Rachel N.; Verhaeghen, Paul

    2013-01-01

    Behavioral evidence from the young suggests spatial cues that orient attention toward task relevant items in visual working memory (VWM) enhance memory capacity. Whether older adults can also use retrospective cues (“retro-cues”) to enhance VWM capacity is unknown. In the current event-related potential (ERP) study, young and old adults performed a VWM task in which spatially informative retro-cues were presented during maintenance. Young but not older adults’ VWM capacity benefitted from retro-cueing. The contralateral delay activity (CDA) ERP index of VWM maintenance was attenuated after the retro-cue, which effectively reduced the impact of memory load. CDA amplitudes were reduced prior to retro-cue onset in the old only. Despite a preserved ability to delete items from VWM, older adults may be less able to use retrospective attention to enhance memory capacity when expectancy of impending spatial cues disrupts effective VWM maintenance. PMID:23445536

  3. Olfactory memory is enhanced in mice exposed to extremely low-frequency electromagnetic fields via Wnt/β-catenin dependent modulation of subventricular zone neurogenesis.

    Science.gov (United States)

    Mastrodonato, Alessia; Barbati, Saviana Antonella; Leone, Lucia; Colussi, Claudia; Gironi, Katia; Rinaudo, Marco; Piacentini, Roberto; Denny, Christine A; Grassi, Claudio

    2018-01-10

    Exposure to extremely low-frequency electromagnetic fields (ELFEF) influences the expression of key target genes controlling adult neurogenesis and modulates hippocampus-dependent memory. Here, we assayed whether ELFEF stimulation affects olfactory memory by modulating neurogenesis in the subventricular zone (SVZ) of the lateral ventricle, and investigated the underlying molecular mechanisms. We found that 30 days after the completion of an ELFEF stimulation protocol (1 mT; 50 Hz; 3.5 h/day for 12 days), mice showed enhanced olfactory memory and increased SVZ neurogenesis. These effects were associated with upregulated expression of mRNAs encoding for key regulators of adult neurogenesis and were mainly dependent on the activation of the Wnt pathway. Indeed, ELFEF stimulation increased Wnt3 mRNA expression and nuclear localization of its downstream target β-catenin. Conversely, inhibition of Wnt3 by Dkk-1 prevented ELFEF-induced upregulation of neurogenic genes and abolished ELFEF's effects on olfactory memory. Collectively, our findings suggest that ELFEF stimulation increases olfactory memory via enhanced Wnt/β-catenin signaling in the SVZ and point to ELFEF as a promising tool for enhancing SVZ neurogenesis and olfactory function.

  4. Enhancement of Phonological Memory Following Transcranial Magnetic Stimulation (TMS

    Directory of Open Access Journals (Sweden)

    Matthew P. Kirschen

    2006-01-01

    Full Text Available Phonologically similar items (mell, rell, gell are more difficult to remember than dissimilar items (shen, floy, stap, likely because of mutual interference of the items in the phonological store. Low-frequency transcranial magnetic stimulation (TMS, guided by functional magnetic resonance imaging (fMRI was used to disrupt this phonological confusion by stimulation of the left inferior parietal (LIP lobule. Subjects received TMS or placebo stimulation while remembering sets of phonologically similar or dissimilar pseudo-words. Consistent with behavioral performance of patients with neurological damage, memory for phonologically similar, but not dissimilar, items was enhanced following TMS relative to placebo stimulation. Stimulation of a control region of the brain did not produce any changes in memory performance. These results provide new insights into how the brain processes verbal information by establishing the necessity of the inferior parietal region for optimal phonological storage. A mechanism is proposed for how TMS reduces phonological confusion and leads to facilitation of phonological memory.

  5. Is emotional memory enhancement preserved in amnestic mild cognitive impairment? Evidence from separating recollection and familiarity.

    Science.gov (United States)

    Wang, Pengyun; Li, Juan; Li, Huijie; Li, Bing; Jiang, Yang; Bao, Feng; Zhang, Shouzi

    2013-11-01

    This study investigated whether the observed absence of emotional memory enhancement in recognition tasks in patients with amnestic mild cognitive impairment (aMCI) could be related to their greater proportion of familiarity-based responses for all stimuli, and whether recognition tests with emotional items had better discriminative power for aMCI patients than those with neutral items. In total, 31 aMCI patients and 30 healthy older adults participated in a recognition test followed by remember/know judgments. Positive, neutral, and negative faces were used as stimuli. For overall recognition performance, emotional memory enhancement was found only in healthy controls; they remembered more negative and positive stimuli than neutral ones. For "remember" responses, we found equivalent emotional memory enhancement in both groups, though a greater proportion of "remember" responses was observed in normal controls. For "know" responses, aMCI patients presented a larger proportion than normal controls did, and their "know" responses were not affected by emotion. A negative correlation was found between emotional enhancement effect and the memory performance related to "know" responses. In addition, receiver operating characteristic curve analysis revealed higher diagnostic accuracy for recognition test with emotional stimuli than with neutral stimuli. The present results implied that the absence of the emotional memory enhancement effect in aMCI patients might be related to their tendency to rely more on familiarity-based "know" responses for all stimuli. Furthermore, recognition memory tests using emotional stimuli may be better able than neutral stimuli to differentiate people with aMCI from cognitively normal older adults. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  6. Semantic Dementia Shows both Storage and Access Disorders of Semantic Memory

    Directory of Open Access Journals (Sweden)

    Yumi Takahashi

    2014-01-01

    Full Text Available Objective. Previous studies have shown that some patients with semantic dementia (SD have memory storage disorders, while others have access disorders. Here, we report three SD cases with both disorders. Methods. Ten pictures and ten words were prepared as visual stimuli to determine if the patients could correctly answer names and select pictures after hearing the names of items (Card Presentation Task, assessing memory storage disorder. In a second task, the viewing time was set at 20 or 300 msec (Momentary Presentation Task, evaluating memory access disorder using items for which correct answers were given in the first task. The results were compared with those for 6 patients with Alzheimer’s disease (AD. Results. The SD patients had lower scores than the AD group for both tasks, suggesting both storage and access disorders. The AD group had almost perfect scores on the Card Presentation Task but showed impairment on the Momentary Presentation Task, although to a lesser extent than the SD cases. Conclusions. These results suggest that SD patients have both storage and access disorders and have more severe access disorder than patients with AD.

  7. Changes in blood glucose and salivary cortisol are not necessary for arousal to enhance memory in young or older adults.

    Science.gov (United States)

    Gore, Jane B; Krebs, Desiree L; Parent, Marise B

    2006-06-01

    Emotional arousal enhances memory, and this memory-enhancing effect may involve neurochemicals released by arousal, such as glucose and cortisol. Physiological consequences of arousal change with age, and these changes may contribute to age-related memory decline. The present study examined whether emotionally arousing pictures would affect glucose and cortisol levels and enhance memory in young and older adults. Blood glucose and salivary cortisol were measured once before and six times after young and old adults viewed either 60 highly arousing or 60 relatively neutral pictures. Recall for the stimuli was measured 75 min later. The results indicated that recall was impaired in older adults. Arousal as measured by self-report enhanced recall in both young and older adults. However, arousal did not affect glucose or cortisol levels in either group. These findings demonstrate that changes in blood glucose or salivary cortisol levels are not necessary for arousal to enhance memory.

  8. Enhanced visual short-term memory in action video game players.

    Science.gov (United States)

    Blacker, Kara J; Curby, Kim M

    2013-08-01

    Visual short-term memory (VSTM) is critical for acquiring visual knowledge and shows marked individual variability. Previous work has illustrated a VSTM advantage among action video game players (Boot et al. Acta Psychologica 129:387-398, 2008). A growing body of literature has suggested that action video game playing can bolster visual cognitive abilities in a domain-general manner, including abilities related to visual attention and the speed of processing, providing some potential bases for this VSTM advantage. In the present study, we investigated the VSTM advantage among video game players and assessed whether enhanced processing speed can account for this advantage. Experiment 1, using simple colored stimuli, revealed that action video game players demonstrate a similar VSTM advantage over nongamers, regardless of whether they are given limited or ample time to encode items into memory. Experiment 2, using complex shapes as the stimuli to increase the processing demands of the task, replicated this VSTM advantage, irrespective of encoding duration. These findings are inconsistent with a speed-of-processing account of this advantage. An alternative, attentional account, grounded in the existing literature on the visuo-cognitive consequences of video game play, is discussed.

  9. Self-reference enhances relational memory in young and older adults.

    Science.gov (United States)

    Hou, Mingzhu; Grilli, Matthew D; Glisky, Elizabeth L

    2017-11-27

    The present study investigated the influence of self-reference on two kinds of relational memory, internal source memory and associative memory, in young and older adults. Participants encoded object-location word pairs using the strategies of imagination and sentence generation, either with reference to themselves or to a famous other (i.e., George Clooney or Oprah Winfrey). Both young and older adults showed memory benefits in the self-reference conditions compared to other-reference conditions on both tests, and the self-referential effects in older adults were not limited by low memory or executive functioning. These results suggest that self-reference can benefit relational memory in older adults relatively independently of basic memory and executive functions.

  10. Effects of Sun ginseng on memory enhancement and hippocampal neurogenesis.

    Science.gov (United States)

    Lee, Chang Hwan; Kim, Jong Min; Kim, Dong Hyun; Park, Se Jin; Liu, Xiaotong; Cai, Mudan; Hong, Jin Gyu; Park, Jeong Hill; Ryu, Jong Hoon

    2013-09-01

    Panax ginseng C.A. Meyer has been used in traditional herb prescriptions for thousands of years. A heat-processing method has been used to increase the efficacy of ginseng, yielding what is known as red ginseng. In addition, recently, a slightly modified heat-processing method was applied to ginseng, to obtain a new type of processed ginseng with increased biological activity; this new form of ginseng is referred to as Sun ginseng (SG). The aim of this study was to investigate the effect of SG on memory enhancement and neurogenesis in the hippocampal dentate gyrus (DG) region. The subchronic administration of SG (for 14 days) significantly increased the latency time in the passive avoidance task relative to the administration of the vehicle control (P memory-enhancing activities and that these effects are mediated, in part, by the increase in the levels of pERK and pAkt and by the increases in cell proliferation and cell survival. Copyright © 2012 John Wiley & Sons, Ltd.

  11. Sex, cheating, and disgust: enhanced source memory for trait information that violates gender stereotypes.

    Science.gov (United States)

    Kroneisen, Meike; Bell, Raoul

    2013-01-01

    The present study examines memory for social-exchange-relevant information. In Experiment 1 male and female faces were shown together with behaviour descriptions of cheating, altruistic, and neutral behaviour. Previous results have led to the hypothesis that people preferentially remember schema-atypical information. Given the common gender stereotype that women are kinder and less egoistic than men, this atypicality account would predict that source memory (that is, memory for the type of context to which a face was associated) should be enhanced for female cheaters in comparison to male cheaters. The results of Experiment 1 confirmed this hypothesis. Experiment 2 reveals that source memory for female faces associated with disgusting behaviours is enhanced in comparison to male faces associated with disgusting behaviours. Thus the atypicality effect generalises beyond social-exchange-relevant information, a result which is inconsistent with the assumption that the findings can be ascribed to a highly specific cheater detection module.

  12. Training Lymnaea in the presence of a predator scent results in a long-lasting ability to form enhanced long-term memory.

    Science.gov (United States)

    Forest, Jeremy; Sunada, Hiroshi; Dodd, Shawn; Lukowiak, Ken

    2016-06-01

    Lymnaea exposed to crayfish effluent (CE) gain an enhanced ability to form long-term memory (LTM). We test the hypothesis that a single CE exposure and operant conditioning training leads to long lasting changes in the capability of snails to form LTM when tested in pond water four weeks later. We trained both juvenile and adult snails with a single 0.5 h training session in CE and show that LTM was present 24 h later. Snails trained in a similar manner in just pond water show no LTM. We then asked if such training in CE conferred enhanced memory forming capabilities on these snails four weeks later. That is, would LTM be formed in these snails four weeks later following a single 0.5 h training session in pond water? We found that both adult and juvenile snails previously trained in CE one month previously had enhanced LTM formation abilities. The injection of a DNA methylation blocker, 5-AZA, prior to training in adult snails blocked enhanced LTM formation four weeks later. Finally, this enhanced LTM forming ability was not passed on to the next generation of snails.

  13. Glucose Administration Enhances fMRI Brain Activation and Connectivity Related to Episodic Memory Encoding for Neutral and Emotional Stimuli

    Science.gov (United States)

    Parent, Marise B.; Krebs-Kraft, Desiree L.; Ryan, John P.; Wilson, Jennifer S.; Harenski, Carla; Hamann, Stephan

    2011-01-01

    Glucose enhances memory in a variety of species. In humans, glucose administration enhances episodic memory encoding, although little is known regarding the neural mechanisms underlying these effects. Here we examined whether elevating blood glucose would enhance functional MRI (fMRI) activation and connectivity in brain regions associated with…

  14. Acute stress enhances learning and memory by activating acid-sensing ion channels in rats.

    Science.gov (United States)

    Ye, Shunjie; Yang, Rong; Xiong, Qiuju; Yang, Youhua; Zhou, Lianying; Gong, Yeli; Li, Changlei; Ding, Zhenhan; Ye, Guohai; Xiong, Zhe

    2018-04-15

    Acute stress has been shown to enhance learning and memory ability, predominantly through the action of corticosteroid stress hormones. However, the valuable targets for promoting learning and memory induced by acute stress and the underlying molecular mechanisms remain unclear. Acid-sensing ion channels (ASICs) play an important role in central neuronal systems and involves in depression, synaptic plasticity and learning and memory. In the current study, we used a combination of electrophysiological and behavioral approaches in an effort to explore the effects of acute stress on ASICs. We found that corticosterone (CORT) induced by acute stress caused a potentiation of ASICs current via glucocorticoid receptors (GRs) not mineralocorticoid receptors (MRs). Meanwhile, CORT did not produce an increase of ASICs current by pretreated with GF109203X, an antagonist of protein kinase C (PKC), whereas CORT did result in a markedly enhancement of ASICs current by bryostatin 1, an agonist of PKC, suggesting that potentiation of ASICs function may be depended on PKC activating. More importantly, an antagonist of ASICs, amiloride (10 μM) reduced the performance of learning and memory induced by acute stress, which is further suggesting that ASICs as the key components involves in cognitive processes induced by acute stress. These results indicate that acute stress causes the enhancement of ASICs function by activating PKC signaling pathway, which leads to potentiated learning and memory. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Stochastic memory: getting memory out of noise

    Science.gov (United States)

    Stotland, Alexander; di Ventra, Massimiliano

    2011-03-01

    Memory circuit elements, namely memristors, memcapacitors and meminductors, can store information without the need of a power source. These systems are generally defined in terms of deterministic equations of motion for the state variables that are responsible for memory. However, in real systems noise sources can never be eliminated completely. One would then expect noise to be detrimental for memory. Here, we show that under specific conditions on the noise intensity memory can actually be enhanced. We illustrate this phenomenon using a physical model of a memristor in which the addition of white noise into the state variable equation improves the memory and helps the operation of the system. We discuss under which conditions this effect can be realized experimentally, discuss its implications on existing memory systems discussed in the literature, and also analyze the effects of colored noise. Work supported in part by NSF.

  16. Selective Entrainment of Theta Oscillations in the Dorsal Stream Causally Enhances Auditory Working Memory Performance.

    Science.gov (United States)

    Albouy, Philippe; Weiss, Aurélien; Baillet, Sylvain; Zatorre, Robert J

    2017-04-05

    The implication of the dorsal stream in manipulating auditory information in working memory has been recently established. However, the oscillatory dynamics within this network and its causal relationship with behavior remain undefined. Using simultaneous MEG/EEG, we show that theta oscillations in the dorsal stream predict participants' manipulation abilities during memory retention in a task requiring the comparison of two patterns differing in temporal order. We investigated the causal relationship between brain oscillations and behavior by applying theta-rhythmic TMS combined with EEG over the MEG-identified target (left intraparietal sulcus) during the silent interval between the two stimuli. Rhythmic TMS entrained theta oscillation and boosted participants' accuracy. TMS-induced oscillatory entrainment scaled with behavioral enhancement, and both gains varied with participants' baseline abilities. These effects were not seen for a melody-comparison control task and were not observed for arrhythmic TMS. These data establish theta activity in the dorsal stream as causally related to memory manipulation. VIDEO ABSTRACT. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Glucose enhancement of memory is modulated by trait anxiety in healthy adolescent males.

    Science.gov (United States)

    Smith, Michael A; Hii, Hilary L; Foster, Jonathan K; van Eekelen, J A M

    2011-01-01

    Glucose administration is associated with memory enhancement in healthy young individuals under conditions of divided attention at encoding. While the specific neurocognitive mechanisms underlying this 'glucose memory facilitation effect' are currently uncertain, it is thought that individual differences in glucoregulatory efficiency may alter an individual's sensitivity to the glucose memory facilitation effect. In the present study, we sought to investigate whether basal hypothalamic-pituitary-adrenal axis function (itself a modulator of glucoregulatory efficiency), baseline self-reported stress and trait anxiety influence the glucose memory facilitation effect. Adolescent males (age range = 14-17 years) were administered glucose and placebo prior to completing a verbal episodic memory task on two separate testing days in a counter-balanced, within-subjects design. Glucose ingestion improved verbal episodic memory performance when memory recall was tested (i) within an hour of glucose ingestion and encoding, and (ii) one week subsequent to glucose ingestion and encoding. Basal hypothalamic-pituitary-adrenal axis function did not appear to influence the glucose memory facilitation effect; however, glucose ingestion only improved memory in participants reporting relatively higher trait anxiety. These findings suggest that the glucose memory facilitation effect may be mediated by biological mechanisms associated with trait anxiety.

  18. Failure of Working Memory Training to Enhance Cognition or Intelligence

    Science.gov (United States)

    Thompson, Todd W.; Waskom, Michael L.; Garel, Keri-Lee A.; Cardenas-Iniguez, Carlos; Reynolds, Gretchen O.; Winter, Rebecca; Chang, Patricia; Pollard, Kiersten; Lala, Nupur; Alvarez, George A.; Gabrieli, John D. E.

    2013-01-01

    Fluid intelligence is important for successful functioning in the modern world, but much evidence suggests that fluid intelligence is largely immutable after childhood. Recently, however, researchers have reported gains in fluid intelligence after multiple sessions of adaptive working memory training in adults. The current study attempted to replicate and expand those results by administering a broad assessment of cognitive abilities and personality traits to young adults who underwent 20 sessions of an adaptive dual n-back working memory training program and comparing their post-training performance on those tests to a matched set of young adults who underwent 20 sessions of an adaptive attentional tracking program. Pre- and post-training measurements of fluid intelligence, standardized intelligence tests, speed of processing, reading skills, and other tests of working memory were assessed. Both training groups exhibited substantial and specific improvements on the trained tasks that persisted for at least 6 months post-training, but no transfer of improvement was observed to any of the non-trained measurements when compared to a third untrained group serving as a passive control. These findings fail to support the idea that adaptive working memory training in healthy young adults enhances working memory capacity in non-trained tasks, fluid intelligence, or other measures of cognitive abilities. PMID:23717453

  19. Failure of working memory training to enhance cognition or intelligence.

    Directory of Open Access Journals (Sweden)

    Todd W Thompson

    Full Text Available Fluid intelligence is important for successful functioning in the modern world, but much evidence suggests that fluid intelligence is largely immutable after childhood. Recently, however, researchers have reported gains in fluid intelligence after multiple sessions of adaptive working memory training in adults. The current study attempted to replicate and expand those results by administering a broad assessment of cognitive abilities and personality traits to young adults who underwent 20 sessions of an adaptive dual n-back working memory training program and comparing their post-training performance on those tests to a matched set of young adults who underwent 20 sessions of an adaptive attentional tracking program. Pre- and post-training measurements of fluid intelligence, standardized intelligence tests, speed of processing, reading skills, and other tests of working memory were assessed. Both training groups exhibited substantial and specific improvements on the trained tasks that persisted for at least 6 months post-training, but no transfer of improvement was observed to any of the non-trained measurements when compared to a third untrained group serving as a passive control. These findings fail to support the idea that adaptive working memory training in healthy young adults enhances working memory capacity in non-trained tasks, fluid intelligence, or other measures of cognitive abilities.

  20. What you see is what you remember : Visual chunking by temporal integration enhances working memory

    NARCIS (Netherlands)

    Akyürek, Elkan G.; Kappelmann, Nils; Volkert, Marc; van Rijn, Hedderik

    2017-01-01

    Human memory benefits from information clustering, which can be accomplished by chunking. Chunking typically relies on expertise and strategy and it is unknown whether perceptual clustering over time, through temporal integration, can also enhance working memory. The current study examined the

  1. Distinctiveness enhances long-term event memory in non-human primates, irrespective of reinforcement.

    Science.gov (United States)

    Lewis, Amy; Call, Josep; Berntsen, Dorthe

    2017-08-01

    Non-human primates are capable of recalling events that occurred as long as 3 years ago, and are able to distinguish between similar events; akin to human memory. In humans, distinctiveness enhances memory for events, however, it is unknown whether the same occurs in non-human primates. As such, we tested three great ape species on their ability to remember an event that varied in distinctiveness. Across three experiments, apes witnessed a baiting event in which one of three identical containers was baited with food. After a delay of 2 weeks, we tested their memory for the location of the baited container. Apes failed to recall the baited container when the event was undistinctive (Experiment 1), but were successful when it was distinctive (Experiment 2), although performance was equally good in a less-distinctive condition. A third experiment (Experiment 3) confirmed that distinctiveness, independent of reinforcement, was a consistent predictor of performance. These findings suggest that distinctiveness may enhance memory for events in non-human primates in the same way as in humans, and provides further evidence of basic similarities between the ways apes and humans remember past events. © 2017 Wiley Periodicals, Inc.

  2. Water-Blown Polyurethane Foams Showing a Reversible Shape-Memory Effect

    Directory of Open Access Journals (Sweden)

    Elena Zharinova

    2016-11-01

    Full Text Available Water-blown polyurethane (PU foams are of enormous technological interest as they are widely applied in various fields, i.e., consumer goods, medicine, automotive or aerospace industries. The discovery of the one-way shape-memory effect in PU foams provided a fresh impetus for extensive investigations on porous polymeric actuators over the past decades. High expansion ratios during the shape-recovery are of special interest when big volume changes are required, for example to fill an aneurysm during micro-invasive surgery or save space during transportation. However, the need to program the foams before each operation cycle could be a drawback impeding the entry of shape-memory polymeric (SMP foams to our daily life. Here, we showed that a reversible shape-memory effect (rSME is achievable for polyurethane water-blown semicrystalline foams. We selected commercially available crystallizable poly(ε-caprolactone-diols of different molecular weight for foams synthesis, followed by investigations of morphology, thermal, thermomechanical and shape-memory properties of obtained compositions. Densities of synthesized foams varied from 110 to 180 kg∙m−3, while peak melting temperatures were composition-dependent and changed from 36 to 47 °C, while the melting temperature interval was around 15 K. All semicrystalline foams exhibited excellent one-way SME with shape-fixity ratios slightly above 100% and shape-recovery ratios from the second cycle of 99%. The composition with broad distribution of molecular weights of poly(ε-caprolactone-diols exhibited an rSME of about 12% upon cyclic heating and cooling from Tlow = 10 °C and Thigh = 47 °C. We anticipate that our experimental study opens a field of systematic investigation of rSMEs in porous polymeric materials on macro and micro scale and extend the application of water-blown polyurethane foams to, e.g., protective covers with zero thermal expansion or even cushions adjustable to a certain body

  3. Recognition memory for low- and high-frequency-filtered emotional faces: Low spatial frequencies drive emotional memory enhancement, whereas high spatial frequencies drive the emotion-induced recognition bias.

    Science.gov (United States)

    Rohr, Michaela; Tröger, Johannes; Michely, Nils; Uhde, Alarith; Wentura, Dirk

    2017-07-01

    This article deals with two well-documented phenomena regarding emotional stimuli: emotional memory enhancement-that is, better long-term memory for emotional than for neutral stimuli-and the emotion-induced recognition bias-that is, a more liberal response criterion for emotional than for neutral stimuli. Studies on visual emotion perception and attention suggest that emotion-related processes can be modulated by means of spatial-frequency filtering of the presented emotional stimuli. Specifically, low spatial frequencies are assumed to play a primary role for the influence of emotion on attention and judgment. Given this theoretical background, we investigated whether spatial-frequency filtering also impacts (1) the memory advantage for emotional faces and (2) the emotion-induced recognition bias, in a series of old/new recognition experiments. Participants completed incidental-learning tasks with high- (HSF) and low- (LSF) spatial-frequency-filtered emotional and neutral faces. The results of the surprise recognition tests showed a clear memory advantage for emotional stimuli. Most importantly, the emotional memory enhancement was significantly larger for face images containing only low-frequency information (LSF faces) than for HSF faces across all experiments, suggesting that LSF information plays a critical role in this effect, whereas the emotion-induced recognition bias was found only for HSF stimuli. We discuss our findings in terms of both the traditional account of different processing pathways for HSF and LSF information and a stimulus features account. The double dissociation in the results favors the latter account-that is, an explanation in terms of differences in the characteristics of HSF and LSF stimuli.

  4. Corticosterone infused into the dorsal striatum selectively enhances memory consolidation of cued water-maze training

    NARCIS (Netherlands)

    Quirarte, Gina L.; Sofia Ledesma de la Teja, I.; Casillas, Miriam; Serafin, Norma; Prado-Alcala, Roberto A.; Roozendaal, Benno

    2009-01-01

    Glucocorticoid hormones enhance memory consolidation of hippocampus-dependent spatial/contextual learning, but little is known about their possible influence on the consolidation of procedural/implicit memory. Therefore, in this study we examined the effect of corticosterone (2, 5, or 10 ng) infused

  5. Memory-enhancing effect of Rhodiola rosea L extract on aged mice

    African Journals Online (AJOL)

    Purpose: The memory-enhancing effects of Rhodiola rosea L. extract (RRLE) ... was obtained from about 1.8 g dried sample, i.e., ... height) with a video camera fixed at the top, and .... Rg1 and Rb1 for their effects on improving scopolamine-.

  6. Glucose administration enhances fMRI brain activation and connectivity related to episodic memory encoding for neutral and emotional stimuli.

    Science.gov (United States)

    Parent, Marise B; Krebs-Kraft, Desiree L; Ryan, John P; Wilson, Jennifer S; Harenski, Carla; Hamann, Stephan

    2011-04-01

    Glucose enhances memory in a variety of species. In humans, glucose administration enhances episodic memory encoding, although little is known regarding the neural mechanisms underlying these effects. Here we examined whether elevating blood glucose would enhance functional MRI (fMRI) activation and connectivity in brain regions associated with episodic memory encoding and whether these effects would differ depending on the emotional valence of the material. We used a double-blind, within-participants, crossover design in which either glucose (50g) or a saccharin placebo were administered before scanning, on days approximately 1 week apart. We scanned healthy young male participants with fMRI as they viewed emotionally arousing negative pictures and emotionally neutral pictures, intermixed with baseline fixation. Free recall was tested at 5 min after scanning and again after 1 day. Glucose administration increased activation in brain regions associated with successful episodic memory encoding. Glucose also enhanced activation in regions whose activity was correlated with subsequent successful recall, including the hippocampus, prefrontal cortex, and other regions, and these effects differed for negative vs. neutral stimuli. Finally, glucose substantially increased functional connectivity between the hippocampus and amygdala and a network of regions previously implicated in successful episodic memory encoding. These findings fit with evidence from nonhuman animals indicating glucose modulates memory by selectively enhancing neural activity in brain regions engaged during memory tasks. Our results highlight the modulatory effects of glucose and the importance of examining both regional changes in activity and functional connectivity to fully characterize the effects of glucose on brain function and memory. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Pitch memory, labelling and disembedding in autism.

    Science.gov (United States)

    Heaton, Pamela

    2003-05-01

    Autistic musical savants invariably possess absolute pitch ability and are able to disembed individual musical tones from chords. Enhanced pitch discrimination and memory has been found in non-savant individuals with autism who also show superior performance on visual disembedding tasks. These experiments investigate the extent that enhanced disembedding ability will be found within the musical domain in autism. High-functioning children with autism, together with age- and intelligence-matched controls, participated in three experiments testing pitch memory, labelling and chord disembedding. The findings from experiment 1 showed enhanced pitch memory and labelling in the autism group. In experiment 2, when subjects were pre-exposed to labelled individual tones, superior chord segmentation was also found. However, in experiment 3, when disembedding performance was less reliant on pitch memory, no group differences emerged and the children with autism, like controls, perceived musical chords holistically. These findings indicate that pitch memory and labelling is superior in autism and can facilitate performance on musical disembedding tasks. However, when task performance does not rely on long-term pitch memory, autistic children, like controls, succumb to the Gestalt qualities of chords.

  8. Administration of riluzole into the basolateral amygdala has an anxiolytic-like effect and enhances recognition memory in the rat.

    Science.gov (United States)

    Sugiyama, Azusa; Saitoh, Akiyoshi; Yamada, Misa; Oka, Jun-Ichiro; Yamada, Mitsuhiko

    2017-06-01

    It is widely thought that inactivation of the glutamatergic system impairs recognition memory in rodents. However, we previously demonstrated that systemic administration of riluzole, which blocks the glutamatergic system, enhances recognition memory in the rat novel object recognition (NOR) test. The mechanisms underlying this paradoxical effect of riluzole on recognition memory remain unclear. In the present study, adult male Wistar rats were bilaterally cannulated in the basolateral amygdala (BLA) to examine the effects of intra-BLA administration of riluzole. We also compared the effects of riluzole with those of d-cycloserine, a partial agonist at the glycine binding site on the N-methyl-d-aspartate (NMDA) receptor. The BLA plays a critical role not only in recognition memory, but also in the regulation of anxiety. In the present study, intra-BLA administration of riluzole or d-cycloserine enhanced recognition memory in the NOR test. It was previously suggested that recognition memory can be strongly affected by the state of anxiety in rodents. Interestingly, intra-BLA administration of riluzole, but not d-cycloserine, produced a potent anxiolytic-like effect in the elevated plus-maze test. Thus, the enhancement of recognition memory by riluzole might be an indirect effect resulting from the anxiolytic-like action of the intra-BLA administration of the drug, and may not be directly related to inhibition of the glutamatergic system. Further studies are needed to clarify the mechanisms underlying the memory enhancing effect of riluzole. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. 17β-estradiol enhances memory duration in the main olfactory bulb in CD-1 mice.

    Science.gov (United States)

    Dillon, T Samuel; Fox, Laura C; Han, Crystal; Linster, Christiane

    2013-12-01

    Rodents rely heavily on odor detection, discrimination, and memory to locate food, find mates, care for pups, and avoid predators. Estrogens have been shown to increase memory retention in rodents performing spatial memory and object placement tasks. Here we evaluate the extent to which 17β-estradiol modulates memory formation and duration in the olfactory system. Adult CD-1 mice were gonadectomized and given either systemic 17β-estradiol replacement, local 17β-estradiol in the main olfactory bulb, or no replacement. Before performing the behavioral task the mice were given saline or PHTPP (an estrogen receptor β [ER-β] antagonist) via bilateral infusion into the main olfactory bulb. As the beta-type estrogen receptor (ER-β) is more abundant than the alpha-type estrogen receptor in the murine main olfactory bulb, the current study focuses on 17β-estradiol and its interactions with ERβ. Habituation, a simple, nonassociative learning task in which an animal is exposed to the same odor over successive presentations, was used to evaluate the animals' ability to detect odors and form an olfactory memory. To evaluate memory duration, we added a final trial of intertrial interval time (30 or 60 min) in which we presented the habituated odor. Neither surgical nor drug manipulation affected the ability of mice to detect or habituate to an odor. After habituation, gonadectomized 17β-estradiol-treated mice retained memory of an odor for 30 min, whereas non-estradiol-treated, 17β-estradiol+ERβ antagonist (PHTPP), and untreated male mice did not remember an odor 30 min after habituation. The results show that both systemic and local bulbar infusions of 17β-estradiol enhance odor memory duration in mice.

  10. Negative affect impairs associative memory but not item memory.

    Science.gov (United States)

    Bisby, James A; Burgess, Neil

    2013-12-17

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

  11. genetic overexpression of NR2B subunit enhances social recognition memory for different strains and species.

    Science.gov (United States)

    Jacobs, Stephanie A; Tsien, Joe Z

    2012-01-01

    The ability to learn and remember conspecifics is essential for the establishment and maintenance of social groups. Many animals, including humans, primates and rodents, depend on stable social relationships for survival. Social learning and social recognition have become emerging areas of interest for neuroscientists but are still not well understood. It has been established that several hormones play a role in the modulation of social recognition including estrogen, oxytocin and arginine vasopression. Relatively few studies have investigated how social recognition might be improved or enhanced. In this study, we investigate the role of the NMDA receptor in social recognition memory, specifically the consequences of altering the ratio of the NR2B:NR2A subunits in the forebrain regions in social behavior. We produced transgenic mice in which the NR2B subunit of the NMDA receptor was overexpressed postnatally in the excitatory neurons of the forebrain areas including the cortex, amygdala and hippocampus. We investigated the ability of both our transgenic animals and their wild-type littermate to learn and remember juvenile conspecifics using both 1-hr and 24-hr memory tests. Our experiments show that the wild-type animals and NR2B transgenic mice preformed similarly in the 1-hr test. However, transgenic mice showed better performances in 24-hr tests of recognizing animals of a different strain or animals of a different species. We conclude that NR2B overexpression in the forebrain enhances social recognition memory for different strains and animal species.

  12. Investigating the enhancing effect of music on autobiographical memory in mild Alzheimer's disease.

    Science.gov (United States)

    Irish, Muireann; Cunningham, Conal J; Walsh, J Bernard; Coakley, Davis; Lawlor, Brian A; Robertson, Ian H; Coen, Robert F

    2006-01-01

    The enhancing effect of music on autobiographical memory recall in mild Alzheimer's disease individuals (n = 10; Mini-Mental State Examination score >17/30) and healthy elderly matched individuals (n = 10; Mini-Mental State Examination score 25-30) was investigated. Using a repeated-measures design, each participant was seen on two occasions: once in music condition (Vivaldi's 'Spring' movement from 'The Four Seasons') and once in silence condition, with order counterbalanced. Considerable improvement was found for Alzheimer individuals' recall on the Autobiographical Memory Interview in the music condition, with an interaction for condition by group (p music condition (p music on autobiographical memory recall.

  13. Neuroprotective and memory enhancing properties of a dual agonist of the FGF receptor and NCAM

    DEFF Research Database (Denmark)

    Enevoldsen, Maj N; Kochoyan, Artur; Jurgenson, Monika

    2012-01-01

    subcutaneous administration, enhances long-term memory in normal mice and ameliorates memory deficit in mice with induced brain inflammation. Moreover, Enreptin reduces cognitive impairment and neuronal death induced by Aß25-35 in a rat model of Alzheimer's disease, and reduces the mortality rate and clinical...

  14. Reversible Inactivation of the Higher Order Auditory Cortex during Fear Memory Consolidation Prevents Memory-Related Activity in the Basolateral Amygdala during Remote Memory Retrieval.

    Science.gov (United States)

    Cambiaghi, Marco; Renna, Annamaria; Milano, Luisella; Sacchetti, Benedetto

    2017-01-01

    Recent findings have shown that the auditory cortex, and specifically the higher order Te2 area, is necessary for the consolidation of long-term fearful memories and that it interacts with the amygdala during the retrieval of long-term fearful memories. Here, we tested whether the reversible blockade of Te2 during memory consolidation may affect the activity changes occurring in the amygdala during the retrieval of fearful memories. To address this issue, we blocked Te2 in a reversible manner during memory consolidation processes. After 4 weeks, we assessed the activity of Te2 and individual nuclei of the amygdala during the retrieval of long-term memories. Rats in which Te2 was inactivated upon memory encoding showed a decreased freezing and failed to show Te2-to-basolateral amygdala (BLA) synchrony during memory retrieval. In addition, the expression of the immediate early gene zif268 in the lateral, basal and central amygdala nuclei did not show memory-related enhancement. As all sites were intact upon memory retrieval, we propose that the auditory cortex represents a key node in the consolidation of fear memories and it is essential for amygdala nuclei to support memory retrieval process.

  15. Survivors of cardiac arrest with good neurological outcome show considerable impairments of memory functioning.

    Science.gov (United States)

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

    2015-03-01

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

  16. Retrieval practice enhances the accessibility but not the quality of memory.

    Science.gov (United States)

    Sutterer, David W; Awh, Edward

    2016-06-01

    Numerous studies have demonstrated that retrieval from long-term memory (LTM) can enhance subsequent memory performance, a phenomenon labeled the retrieval practice effect. However, the almost exclusive reliance on categorical stimuli in this literature leaves open a basic question about the nature of this improvement in memory performance. It has not yet been determined whether retrieval practice improves the probability of successful memory retrieval or the quality of the retrieved representation. To answer this question, we conducted three experiments using a mixture modeling approach (Zhang & Luck, 2008) that provides a measure of both the probability of recall and the quality of the recalled memories. Subjects attempted to memorize the color of 400 unique shapes. After every 10 images were presented, subjects either recalled the last 10 colors (the retrieval practice condition) by clicking on a color wheel with each shape as a retrieval cue or they participated in a control condition that involved no further presentations (Experiment 1) or restudy of the 10 shape/color associations (Experiments 2 and 3). Performance in a subsequent delayed recall test revealed a robust retrieval practice effect. Subjects recalled a significantly higher proportion of items that they had previously retrieved relative to items that were untested or that they had restudied. Interestingly, retrieval practice did not elicit any improvement in the precision of the retrieved memories. The same empirical pattern also was observed following delays of greater than 24 hours. Thus, retrieval practice increases the probability of successful memory retrieval but does not improve memory quality.

  17. Enhanced associative memory for colour (but not shape or location) in synaesthesia.

    OpenAIRE

    Pritchard Jamie; Rothen Nicolas; Coolbear Daniel; Ward Jamie

    2013-01-01

    People with grapheme colour synaesthesia have been shown to have enhanced memory on a range of tasks using both stimuli that induce synaesthesia (e.g. words) and more surprisingly stimuli that do not (e.g. certain abstract visual stimuli). This study examines the latter by using multi featured stimuli consisting of shape colour and location conjunctions (e.g. shape A+colour A+location A; shape B+colour B+location B) presented in a recognition memory paradigm. This enables distractor items to ...

  18. In the white cube: museum context enhances the valuation and memory of art.

    Science.gov (United States)

    Brieber, David; Nadal, Marcos; Leder, Helmut

    2015-01-01

    Art museum attendance is rising steadily, unchallenged by online alternatives. However, the psychological value of the real museum experience remains unclear because the experience of art in the museum and other contexts has not been compared. Here we examined the appreciation and memory of an art exhibition when viewed in a museum or as a computer simulated version in the laboratory. In line with the postulates of situated cognition, we show that the experience of art relies on organizing resources present in the environment. Specifically, artworks were found more arousing, positive, interesting and liked more in the museum than in the laboratory. Moreover, participants who saw the exhibition in the museum later recalled more artworks and used spatial layout cues for retrieval. Thus, encountering real art in the museum enhances cognitive and affective processes involved in the appreciation of art and enriches information encoded in long-term memory. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Timing matters: negative emotion elicited 5 min but not 30 min or 45 min after learning enhances consolidation of internal-monitoring source memory.

    Science.gov (United States)

    Wang, Bo; Bukuan, Sun

    2015-05-01

    Two experiments examined the time-dependent effects of negative emotion on consolidation of item and internal-monitoring source memory. In Experiment 1, participants (n=121) learned a list of words. They were asked to read aloud half of the words and to think about the remaining half. They were instructed to memorize each word and its associative cognitive operation ("reading" versus "thinking"). Immediately following learning they conducted free recall and then watched a 3-min either neutral or negative video clip when 5 min, 30 min or 45 min had elapsed after learning. Twenty-four hours later they returned to take surprise tests for item and source memory. Experiment 2 was similar to Experiment 1 except that participants, without conducting an immediate test of free recall, took tests of source memory for all encoded words both immediately and 24 h after learning. Experiment 1 showed that negative emotion enhanced consolidation of item memory (as measured by retention ratio of free recall) regardless of delay of emotion elicitation and that negative emotion enhanced consolidation of source memory when it was elicited at a 5 min delay but reduced consolidation of source memory when it was elicited at a 30 min delay; when elicited at a 45 min delay, negative emotion had little effect. Furthermore, Experiment 2 replicated the enhancement effect on source memory in the 5 min delay even when participants were tested on all the encoded words. The current study partially replicated prior studies on item memory and extends the literature by providing evidence for a time-dependent effect of negative emotion on consolidation of source memory based on internal monitoring. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Phosphodiesterase inhibitors enhance object memory independent of cerebral blood flow and glucose utilization in rats.

    Science.gov (United States)

    Rutten, Kris; Van Donkelaar, Eva L; Ferrington, Linda; Blokland, Arjan; Bollen, Eva; Steinbusch, Harry Wm; Kelly, Paul At; Prickaerts, Jos Hhj

    2009-07-01

    Phosphodiesterase (PDE) inhibitors prevent the breakdown of the second messengers, cyclic AMP (cAMP) and cyclic GMP (cGMP), and are currently studied as possible targets for cognitive enhancement. Earlier studies indicated beneficial effects of PDE inhibitors in object recognition. In this study we tested the effects of three PDE inhibitors on spatial memory as assessed in a place and object recognition task. Furthermore, as both cAMP and cGMP are known vasodilators, the effects of PDE inhibition on cognitive functions could be explained by enhancement of cerebrovascular function. We examined this possibility by measuring the effects of PDE5 and PDE4 inhibitor treatment on local cerebral blood flow and glucose utilization in rats using [14C]-iodoantipyrine and [14C]-2-deoxyglucose quantitative autoradiography, respectively. In the spatial location task, PDE5 inhibition (cGMP) with vardenafil enhanced only early phase consolidation, PDE4 inhibition (cAMP) with rolipram enhanced only late phase consolidation, and PDE2 inhibition (cAMP and cGMP) with Bay 60-7550 enhanced both consolidation processes. Furthermore, PDE5 inhibition had no cerebrovascular effects in hippocampal or rhinal areas. PDE4 inhibition increased rhinal, but not hippocampal blood flow, whereas it decreased glucose utilization in both areas. In general, PDE5 inhibition decreased the ratio between blood flow and glucose utilization, indicative of general oligaemia; whereas PDE4 inhibition increased this ratio, indicative of general hyperemia. Both oligaemic and hyperemic conditions are detrimental for brain function and do not explain memory enhancement. These results underscore the specific effects of cAMP and cGMP on memory consolidation (object and spatial memory) and provide evidence that the underlying mechanisms of PDE inhibition on cognition are independent of cerebrovascular effects.

  1. Enhancing memory performance after organic brain disease relies on retrieval processes rather than encoding or consolidation

    NARCIS (Netherlands)

    Hildebrandt, H.; Gehrmann, A.; Mödden, C.; Eling, P.A.T.M.

    2011-01-01

    Neuropsychological rehabilitation of memory performance is still a controversial topic, and rehabilitation studies have not analyzed to which stage of memory processing (encoding, consolidation, or retrieval) enhancement may be attributed. We first examined the efficacy of a computer training

  2. Enhanced effects of cortisol administration on episodic and working memory in aging veterans with PTSD.

    Science.gov (United States)

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

    2007-12-01

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

  3. Enhancement of striatum-dependent memory by conditioned fear is mediated by beta-adrenergic receptors in the basolateral amygdala

    Directory of Open Access Journals (Sweden)

    Travis D. Goode

    2016-06-01

    Full Text Available Emotional arousal can have a profound impact on various learning and memory processes. For example, unconditioned emotional stimuli (e.g., predator odor or anxiogenic drugs enhance dorsolateral striatum (DLS-dependent habit memory. These effects critically depend on a modulatory role of the basolateral complex of the amygdala (BLA. Recent work indicates that, like unconditioned emotional stimuli, exposure to an aversive conditioned stimulus (CS (i.e., a tone previously paired with shock can also enhance consolidation of DLS-dependent habit memory. The present experiments examined whether noradrenergic activity, particularly within the BLA, is required for a fear CS to enhance habit memory consolidation. First, rats underwent a fear conditioning procedure in which a tone CS was paired with an aversive unconditioned stimulus. Over the course of the next five days, rats received training in a DLS-dependent water plus-maze task, in which rats were reinforced to make a consistent body-turn response to reach a hidden escape platform. Immediately after training on days 1–3, rats received post-training systemic (Experiment 1 or intra-BLA (Experiment 2 administration of the β-adrenoreceptor antagonist, propranolol. Immediately after drug administration, half of the rats were re-exposed to the tone CS in the conditioning context (without shock. Post-training CS exposure enhanced consolidation of habit memory in vehicle-treated rats, and this effect was blocked by peripheral (Experiment 1 or intra-BLA (Experiment 2 propranolol administration. The present findings reveal that noradrenergic activity within the BLA is critical for the enhancement of DLS-dependent habit memory as a result of exposure to conditioned emotional stimuli.

  4. Enhancement of Continuous Variable Entanglement in Four-Wave Mixing due to Atomic Memory Effects

    International Nuclear Information System (INIS)

    Yu-Zhu, Zhu; Xiang-Ming, Hu; Fei, Wang; Jing-Yan, Li

    2010-01-01

    We explore the effects of atomic memory on quantum correlations of two-mode light fields from four-wave mixing. A three-level atomic system in Λ configuration is considered, in which the atomic relaxation times are comparable to or longer than the cavity relaxation times and thus there exists the atomic memory. The quantum correlation spectrum in the output is calculated without the adiabatic elimination of atomic variables. It is shown that the continuous variable entanglement is enhanced over a wide range of the normalized detuning in the intermediate and bad cavity cases compared with the good cavity case. In some situations more significant enhancement occurs at sidebands

  5. [Spontaneous enhancement of long-term memory retrieval during a few days after training].

    Science.gov (United States)

    Solntseva, S V; Storozheva, Z I; Nikitin, V P; Sherstnev, V V

    2013-03-01

    The dynamics of long-term memory retrieval on the 1st and 5th days after rat training in spatial Morris water maze and snail conditioned taste aversion models was studied. It was found that animals trained for several days displayed stable and high level of memory retrieval both on 1st and on 5th days after training. Under conditions of single-session training the rate of memory retrieval in snails and rats on the 5th day was higher than on the 1st day after training. It has been proposed that spontaneous enhancement of habit retrieval during 5-days time interval after training is a result of "lingering" memory consolidation processes, which includes trace reorganization in particular molecular and morphological changes in animal brain neurons.

  6. Decreased in vitro mitochondrial function is associated with enhanced brain metabolism, blood flow, and memory in Surf1-deficient mice

    Science.gov (United States)

    Lin, Ai-Ling; Pulliam, Daniel A; Deepa, Sathyaseelan S; Halloran, Jonathan J; Hussong, Stacy A; Burbank, Raquel R; Bresnen, Andrew; Liu, Yuhong; Podlutskaya, Natalia; Soundararajan, Anuradha; Muir, Eric; Duong, Timothy Q; Bokov, Alex F; Viscomi, Carlo; Zeviani, Massimo; Richardson, Arlan G; Van Remmen, Holly; Fox, Peter T; Galvan, Veronica

    2013-01-01

    Recent studies have challenged the prevailing view that reduced mitochondrial function and increased oxidative stress are correlated with reduced longevity. Mice carrying a homozygous knockout (KO) of the Surf1 gene showed a significant decrease in mitochondrial electron transport chain Complex IV activity, yet displayed increased lifespan and reduced brain damage after excitotoxic insults. In the present study, we examined brain metabolism, brain hemodynamics, and memory of Surf1 KO mice using in vitro measures of mitochondrial function, in vivo neuroimaging, and behavioral testing. We show that decreased respiration and increased generation of hydrogen peroxide in isolated Surf1 KO brain mitochondria are associated with increased brain glucose metabolism, cerebral blood flow, and lactate levels, and with enhanced memory in Surf1 KO mice. These metabolic and functional changes in Surf1 KO brains were accompanied by higher levels of hypoxia-inducible factor 1 alpha, and by increases in the activated form of cyclic AMP response element-binding factor, which is integral to memory formation. These findings suggest that Surf1 deficiency-induced metabolic alterations may have positive effects on brain function. Exploring the relationship between mitochondrial activity, oxidative stress, and brain function will enhance our understanding of cognitive aging and of age-related neurologic disorders. PMID:23838831

  7. Motivation enhances visual working memory capacity through the modulation of central cognitive processes.

    Science.gov (United States)

    Sanada, Motoyuki; Ikeda, Koki; Kimura, Kenta; Hasegawa, Toshikazu

    2013-09-01

    Motivation is well known to enhance working memory (WM) capacity, but the mechanism underlying this effect remains unclear. The WM process can be divided into encoding, maintenance, and retrieval, and in a change detection visual WM paradigm, the encoding and retrieval processes can be subdivided into perceptual and central processing. To clarify which of these segments are most influenced by motivation, we measured ERPs in a change detection task with differential monetary rewards. The results showed that the enhancement of WM capacity under high motivation was accompanied by modulations of late central components but not those reflecting attentional control on perceptual inputs across all stages of WM. We conclude that the "state-dependent" shift of motivation impacted the central, rather than the perceptual functions in order to achieve better behavioral performances. Copyright © 2013 Society for Psychophysiological Research.

  8. Stress, memory, and the hippocampus.

    Science.gov (United States)

    Wingenfeld, Katja; Wolf, Oliver T

    2014-01-01

    Stress hormones, i.e. cortisol in human and cortisone in rodents, influence a wide range of cognitive functions, including hippocampus-based declarative memory performance. Cortisol enhances memory consolidation, but impairs memory retrieval. In this context glucocorticoid receptor sensitivity and hippocampal integrity play an important role. This review integrates findings on the relationships between the hypothalamus-pituitary-adrenal (HPA) axis, one of the main coordinators of the stress response, hippocampus, and memory. Findings obtained in healthy participants will be compared with selected mental disorders, including major depressive disorder (MDD), posttraumatic stress disorder (PTSD), and borderline personality disorder (BPD). These disorders are characterized by alterations of the HPA axis and hippocampal dysfunctions. Interestingly, the acute effects of stress hormones on memory in psychiatric patients are different from those found in healthy humans. While cortisol administration has failed to affect memory retrieval in patients with MDD, patients with PTSD and BPD have been found to show enhanced rather than impaired memory retrieval after hydrocortisone. This indicates an altered sensitivity to stress hormones in these mental disorders. © 2014 S. Karger AG, Basel

  9. Acute ingestion of different macronutrients differentially enhances aspects of memory and attention in healthy young adults.

    Science.gov (United States)

    Jones, Emma K; Sünram-Lea, Sandra I; Wesnes, Keith A

    2012-02-01

    The role of carbohydrates on mood and cognition is fairly well established, however research examining the behavioural effects of the other macronutrients is limited. The current study compared the effects of a 25 g glucose drink to energetically matched protein and fat drinks and an inert placebo. Following a blind, placebo-controlled, randomised crossover design, 18 healthy young adults consumed drinks containing fat, glucose, protein and placebo. Cognitive performance was examined at baseline and again 15- and 60 min post drink. Mood was assessed at baseline and then 10-, 35- and 80 min post drink. Attention and speed were enhanced 15 min following fat or glucose ingestion and working memory was enhanced 15 min following protein ingestion. Sixty minutes post drink memory enhancements were observed after protein and memory impairment was observed following glucose. All drinks increased ratings of alertness. The findings suggest that macronutrients: (i) have different windows of opportunity for effects (ii) target different cognitive domains. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Development and optimization of dispersible tablet of Bacopa monnieri with improved functionality for memory enhancement

    Directory of Open Access Journals (Sweden)

    Vaishali Tejas Thakkar

    2017-01-01

    Full Text Available Introduction: The Bacopa monnieri is traditional Ayurvedic medicine, and reported for memory-enhancing effects. The Bacoside is poorly soluble, bitter in taste and responsible for the memory enhancement action. Memory enhancer is commonly prescribed for children or elder people. Objective: Poor solubility, patient compliance and bitterness were a major driving force to develop taste masked β-cyclodextrin complex and dispersible tablets. Materials and Methods: The inclusion complex of Bacopa monnieri and β-cyclodextrin was prepared in different molar ratios of Bacopa monnieri by Co-precipitation method. Phase solubility study was conducted to evaluate the effect of β-cyclodextrin on aqueous solubility of Bacoside A. The characterization was determined by Fourier transformation infrared spectroscopy (FTIR,Differential scanning calorimetry (DSC and X-ray diffraction study (XRD.Crospovidone and croscarmallose sodium were used as super disintigrant.The 32 full factorial design was adopted to investigate the influence of two superdisintegrants on the wetting time and disntegration time of the tablets. Conclusion: The result revels that molar ratio (1:4 of inclusion complex enhance 3-fold solubility. Full factorial design was successfully employed for the optimization of dispersible tablet of B. monnieri . The short-term accelerated stability study confirmed that high stability of B. monnieri in inclusion complex.

  11. Enhancing effects of acute psychosocial stress on priming of non-declarative memory in healthy young adults.

    Science.gov (United States)

    Hidalgo, Vanesa; Villada, Carolina; Almela, Mercedes; Espín, Laura; Gómez-Amor, Jesús; Salvador, Alicia

    2012-05-01

    Social stress affects cognitive processes in general, and memory performance in particular. However, the direction of these effects has not been clearly established, as it depends on several factors. Our aim was to determine the impact of the hypothalamus-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) reactivity to psychosocial stress on short-term non-declarative memory and declarative memory performance. Fifty-two young participants (18 men, 34 women) were subjected to the Trier Social Stress Task (TSST) and a control condition in a crossover design. Implicit memory was assessed by a priming test, and explicit memory was assessed by the Rey Auditory Verbal Learning Test (RAVLT). The TSST provoked greater salivary cortisol and salivary alpha-amylase (sAA) responses than the control task. Men had a higher cortisol response to stress than women, but no sex differences were found for sAA release. Stress was associated with an enhancement of priming but did not affect declarative memory. Additionally, the enhancement on the priming test was higher in those whose sAA levels increased more in response to stress (r(48) = 0.339, p = 0.018). Our results confirm an effect of acute stress on priming, and that this effect is related to SNS activity. In addition, they suggest a different relationship between stress biomarkers and the different memory systems.

  12. Acoustic Enhancement of Sleep Slow Oscillations and Concomitant Memory Improvement in Older Adults

    Science.gov (United States)

    Papalambros, Nelly A.; Santostasi, Giovanni; Malkani, Roneil G.; Braun, Rosemary; Weintraub, Sandra; Paller, Ken A.; Zee, Phyllis C.

    2017-01-01

    Acoustic stimulation methods applied during sleep in young adults can increase slow wave activity (SWA) and improve sleep-dependent memory retention. It is unknown whether this approach enhances SWA and memory in older adults, who generally have reduced SWA compared to younger adults. Additionally, older adults are at risk for age-related cognitive impairment and therefore may benefit from non-invasive interventions. The aim of this study was to determine if acoustic stimulation can increase SWA and improve declarative memory in healthy older adults. Thirteen participants 60–84 years old completed one night of acoustic stimulation and one night of sham stimulation in random order. During sleep, a real-time algorithm using an adaptive phase-locked loop modeled the phase of endogenous slow waves in midline frontopolar electroencephalographic recordings. Pulses of pink noise were delivered when the upstate of the slow wave was predicted. Each interval of five pulses (“ON interval”) was followed by a pause of approximately equal length (“OFF interval”). SWA during the entire sleep period was similar between stimulation and sham conditions, whereas SWA and spindle activity were increased during ON intervals compared to matched periods during the sham night. The increases in SWA and spindle activity were sustained across almost the entire five-pulse ON interval compared to matched sham periods. Verbal paired-associate memory was tested before and after sleep. Overnight improvement in word recall was significantly greater with acoustic stimulation compared to sham and was correlated with changes in SWA between ON and OFF intervals. Using the phase-locked-loop method to precisely target acoustic stimulation to the upstate of sleep slow oscillations, we were able to enhance SWA and improve sleep-dependent memory storage in older adults, which strengthens the theoretical link between sleep and age-related memory integrity. PMID:28337134

  13. tDCS for Memory Enhancement: Analysis of the Speculative Aspects of Ethical Issues.

    Science.gov (United States)

    Voarino, Nathalie; Dubljević, Veljko; Racine, Eric

    2016-01-01

    Transcranial direct current stimulation (tDCS) is a promising technology to enhance cognitive and physical performance. One of the major areas of interest is the enhancement of memory function in healthy individuals. The early arrival of tDCS on the market for lifestyle uses and cognitive enhancement purposes lead to the voicing of some important ethical concerns, especially because, to date, there are no official guidelines or evaluation procedures to tackle these issues. The aim of this article is to review ethical issues related to uses of tDCS for memory enhancement found in the ethics and neuroscience literature and to evaluate how realistic and scientifically well-founded these concerns are? In order to evaluate how plausible or speculative each issue is, we applied the methodological framework described by Racine et al. (2014) for "informed and reflective" speculation in bioethics. This framework could be succinctly presented as requiring: (1) the explicit acknowledgment of factual assumptions and identification of the value attributed to them; (2) the validation of these assumptions with interdisciplinary literature; and (3) the adoption of a broad perspective to support more comprehensive reflection on normative issues. We identified four major considerations associated with the development of tDCS for memory enhancement: safety, autonomy, justice and authenticity. In order to assess the seriousness and likelihood of harm related to each of these concerns, we analyzed the assumptions underlying the ethical issues, and the level of evidence for each of them. We identified seven distinct assumptions: prevalence, social acceptance, efficacy, ideological stance (bioconservative vs. libertarian), potential for misuse, long term side effects, and the delivery of complete and clear information. We conclude that ethical discussion about memory enhancement via tDCS sometimes involves undue speculation, and closer attention to scientific and social facts would bring

  14. Emotional Memory Persists Longer than Event Memory

    Science.gov (United States)

    Kuriyama, Kenichi; Soshi, Takahiro; Fujii, Takeshi; Kim, Yoshiharu

    2010-01-01

    The interaction between amygdala-driven and hippocampus-driven activities is expected to explain why emotion enhances episodic memory recognition. However, overwhelming behavioral evidence regarding the emotion-induced enhancement of immediate and delayed episodic memory recognition has not been obtained in humans. We found that the recognition…

  15. Therapeutic-Ultrasound-Triggered Shape Memory of a Melamine-Enhanced Poly(vinyl alcohol) Physical Hydrogel.

    Science.gov (United States)

    Li, Guo; Yan, Qiang; Xia, Hesheng; Zhao, Yue

    2015-06-10

    Therapeutic-ultrasound-triggered shape memory was demonstrated for the first time with a melamine-enhanced poly(vinyl alcohol) (PVA) physical hydrogel. The addition of a small amount of melamine (up to 1.5 wt %) in PVA results in a strong hydrogel due to the multiple H-bonding between the two constituents. A temporary shape of the hydrogel can be obtained by deformation of the hydrogel (∼65 wt % water) at room temperature, followed by fixation of the deformation by freezing/thawing the hydrogel under strain, which induces crystallization of PVA. We show that the ultrasound delivered by a commercially available device designed for the patient's pain relief could trigger the shape recovery process as a result of ultrasound-induced local heating in the hydrogel that melts the crystallized PVA cross-linking. This hydrogel is thus interesting for potential applications because it combines many desirable properties, being mechanically strong, biocompatible, and self-healable and displaying the shape memory capability triggered by a physiological stimulus.

  16. The Dark Side of Testing Memory: Repeated Retrieval Can Enhance Eyewitness Suggestibility

    Science.gov (United States)

    Chan, Jason C. K.; LaPaglia, Jessica A.

    2011-01-01

    Eyewitnesses typically recount their experiences many times before trial. Such repeated retrieval can enhance memory retention of the witnessed event. However, recent studies (e.g., Chan, Thomas, & Bulevich, 2009) have found that initial retrieval can exacerbate eyewitness suggestibility to later misleading information--a finding termed…

  17. Memory-enhancing effect of Rhodiola rosea L extract on aged mice ...

    African Journals Online (AJOL)

    Purpose: The memory-enhancing effects of Rhodiola rosea L. extract (RRLE) on normal aged mice were assessed. Methods: In the open-field test, the effect of RRLE (150 and 300 mg/kg) on mouse locomotive activities was evaluated by investigating the extract's influence on CAT and AchE activities in the brain tissue of ...

  18. Rapid-Eye-Movement-Sleep (REM Associated Enhancement of Working Memory Performance after a Daytime Nap.

    Directory of Open Access Journals (Sweden)

    Esther Yuet Ying Lau

    Full Text Available The main objective was to study the impact of a daytime sleep opportunity on working memory and the mechanism behind such impact. This study adopted an experimental design in a sleep research laboratory. Eighty healthy college students (Age:17-23, 36 males were randomized to either have a polysomnography-monitored daytime sleep opportunity (Nap-group, n=40 or stay awake (Wake-group, n=40 between the two assessment sessions. All participants completed a sleep diary and wore an actigraph-watch for 5 days before and one day after the assessment sessions. They completed the state-measurement of sleepiness and affect, in addition to a psychomotor vigilance test and a working memory task before and after the nap/wake sessions. The two groups did not differ in their sleep characteristics prior to and after the lab visit. The Nap-group had higher accuracy on the working memory task, fewer lapses on the psychomotor vigilance test and lower state-sleepiness than the Wake-group. Within the Nap-group, working memory accuracy was positively correlated with duration of rapid eye movement sleep (REM and total sleep time during the nap. Our findings suggested that "sleep gain" during a daytime sleep opportunity had significant positive impact on working memory performance, without affecting subsequent nighttime sleep in young adult, and such impact was associated with the duration of REM. While REM abnormality has long been noted in pathological conditions (e.g. depression, which are also presented with cognitive dysfunctions (e.g. working memory deficits, this was the first evidence showing working memory enhancement associated with REM in daytime napping in college students, who likely had habitual short sleep duration but were otherwise generally healthy.

  19. Rapid-Eye-Movement-Sleep (REM) Associated Enhancement of Working Memory Performance after a Daytime Nap

    Science.gov (United States)

    Lau, Kristy Nga Ting; Hui, Florence Wai Ying; Tseng, Chia-huei

    2015-01-01

    The main objective was to study the impact of a daytime sleep opportunity on working memory and the mechanism behind such impact. This study adopted an experimental design in a sleep research laboratory. Eighty healthy college students (Age:17-23, 36 males) were randomized to either have a polysomnography-monitored daytime sleep opportunity (Nap-group, n=40) or stay awake (Wake-group, n=40) between the two assessment sessions. All participants completed a sleep diary and wore an actigraph-watch for 5 days before and one day after the assessment sessions. They completed the state-measurement of sleepiness and affect, in addition to a psychomotor vigilance test and a working memory task before and after the nap/wake sessions. The two groups did not differ in their sleep characteristics prior to and after the lab visit. The Nap-group had higher accuracy on the working memory task, fewer lapses on the psychomotor vigilance test and lower state-sleepiness than the Wake-group. Within the Nap-group, working memory accuracy was positively correlated with duration of rapid eye movement sleep (REM) and total sleep time during the nap. Our findings suggested that “sleep gain” during a daytime sleep opportunity had significant positive impact on working memory performance, without affecting subsequent nighttime sleep in young adult, and such impact was associated with the duration of REM. While REM abnormality has long been noted in pathological conditions (e.g. depression), which are also presented with cognitive dysfunctions (e.g. working memory deficits), this was the first evidence showing working memory enhancement associated with REM in daytime napping in college students, who likely had habitual short sleep duration but were otherwise generally healthy. PMID:25970511

  20. Divided attention enhances explicit but not implicit conceptual memory: an item-specific account of the attentional boost effect.

    Science.gov (United States)

    Spataro, Pietro; Mulligan, Neil W; Bechi Gabrielli, Giulia; Rossi-Arnaud, Clelia

    2017-02-01

    The Attentional Boost Effect (ABE) refers to the counterintuitive finding that words encoded with to-be-responded targets in a divided-attention condition are remembered better than words encoded with distractors. Previous studies suggested that the ABE-related enhancement of verbal memory depends upon the activation of abstract lexical representations. In the present study, we extend this hypothesis by embedding it in the context of a broader perspective, which proposes that divided attention in the ABE paradigm affects item-specific, but not relational, processing. To this purpose, we examined the ABE in the matched tasks of category-cued recall (CCRT: explicit memory) and category exemplar generation (CEGT: implicit memory). In addition, study time was varied (500, 1500 or 4000 ms), to further determine whether the attentional boost manipulation could influence late-phase elaborative processing. In agreement with the predictions of the item-specific account, the results showed that exemplars encoded with targets were recalled better than exemplars encoded with distractors in the CCRT, but not in the CEGT. Moreover, performance in the CCRT increased with study time, whereas the size of the ABE-related enhancement tended to decrease, further confirming that this effect hinges upon early phase encoding processes.

  1. Dreaming of a Learning Task is Associated with Enhanced Sleep-Dependent Memory Consolidation

    Science.gov (United States)

    Wamsley, Erin J.; Tucker, Matthew; Payne, Jessica D.; Benavides, Joseph; Stickgold, Robert

    2010-01-01

    Summary It is now well established that post-learning sleep is beneficial for human memory performance [1–5]. Meanwhile, human and animal studies demonstrate that learning-related neural activity is re-expressed during post-training non-rapid eye movement sleep (NREM) [6–9]. NREM sleep processes appear to be particularly beneficial for hippocampus-dependent forms of memory [1–3, 10]. 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 (n=99) were trained on a virtual navigation task, and then retested on the same task 5 hours 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 seen during wakefulness suggests that these mnemonic processes are specific to the sleep state. PMID:20417102

  2. Quantum entanglement enhances the capacity of bosonic channels with memory

    International Nuclear Information System (INIS)

    Cerf, Nicolas J.; Clavareau, Julien; Macchiavello, Chiara; Roland, Jeremie

    2005-01-01

    The bosonic quantum channels have recently attracted a growing interest, motivated by the hope that they open a tractable approach to the generally hard problem of evaluating quantum channel capacities. These studies, however, have always been restricted to memoryless channels. Here, it is shown that the classical capacity of a bosonic Gaussian channel with memory can be significantly enhanced if entangled symbols are used instead of product symbols. For example, the capacity of a photonic channel with 70%-correlated thermal noise of one-third the shot noise is enhanced by about 11% when using 3.8-dB entangled light with a modulation variance equal to the shot noise

  3. Glucose enhancement of recognition memory: differential effects on effortful processing but not aspects of 'remember-know' responses.

    Science.gov (United States)

    Scholey, Andrew; Macpherson, Helen; Sünram-Lea, Sandra; Elliott, Jade; Stough, Con; Kennedy, David

    2013-01-01

    The administration of a glucose drink has been shown to enhance cognitive performance with effect sizes comparable with those from pharmaceutical interventions in human trials. In the memory domain, it is currently debated whether glucose facilitation of performance is due to differential targeting of hippocampal memory or whether task effort is a more important determinant. Using a placebo-controlled, double-blind, crossover 2(Drink: glucose/placebo) × 2(Effort: ± secondary task) design, 20 healthy young adults' recognition memory performance was measured using the 'remember-know' procedure. Two high effort conditions (one for each drink) included secondary hand movements during word presentation. A 25 g glucose or 30 mg saccharine (placebo) drink was consumed 10 min prior to the task. The presence of a secondary task resulted in a global impairment of memory function. There were significant Drink × Effort interactions for overall memory accuracy but no differential effects for 'remember' or 'know' responses. These data suggest that, in some circumstances, task effort may be a more important determinant of the glucose facilitation of memory effect than hippocampal mediation. This article is part of a Special Issue entitled 'Cognitive Enhancers'. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Repeated administration of almonds increases brain acetylcholine levels and enhances memory function in healthy rats while attenuates memory deficits in animal model of amnesia.

    Science.gov (United States)

    Batool, Zehra; Sadir, Sadia; Liaquat, Laraib; Tabassum, Saiqa; Madiha, Syeda; Rafiq, Sahar; Tariq, Sumayya; Batool, Tuba Sharf; Saleem, Sadia; Naqvi, Fizza; Perveen, Tahira; Haider, Saida

    2016-01-01

    Dietary nutrients may play a vital role in protecting the brain from age-related memory dysfunction and neurodegenerative diseases. Tree nuts including almonds have shown potential to combat age-associated brain dysfunction. These nuts are an important source of essential nutrients, such as tocopherol, folate, mono- and poly-unsaturated fatty acids, and polyphenols. These components have shown promise as possible dietary supplements to prevent or delay the onset of age-associated cognitive dysfunction. This study investigated possible protective potential of almond against scopolamine induced amnesia in rats. The present study also investigated a role of acetylcholine in almond induced memory enhancement. Rats in test group were orally administrated with almond suspension (400 mg/kg/day) for four weeks. Both control and almond-treated rats were then divided into saline and scopolamine injected groups. Rats in the scopolamine group were injected with scopolamine (0.5 mg/kg) five minutes before the start of each memory test. Memory was assessed by elevated plus maze (EPM), Morris water maze (MWM) and novel object recognition (NOR) task. Cholinergic function was determined in terms of hippocampal and frontal cortical acetylcholine content and acetylcholinesterase activity. Results of the present study suggest that almond administration for 28 days significantly improved memory retention. This memory enhancing effect of almond was also observed in scopolamine induced amnesia model. Present study also suggests a role of acetylcholine in the attenuation of scopolamine induced amnesia by almond. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Discovery of Selective Phosphodiesterase 1 Inhibitors with Memory Enhancing Properties.

    Science.gov (United States)

    Dyck, Brian; Branstetter, Bryan; Gharbaoui, Tawfik; Hudson, Andrew R; Breitenbucher, J Guy; Gomez, Laurent; Botrous, Iriny; Marrone, Tami; Barido, Richard; Allerston, Charles K; Cedervall, E Peder; Xu, Rui; Sridhar, Vandana; Barker, Ryan; Aertgeerts, Kathleen; Schmelzer, Kara; Neul, David; Lee, Dong; Massari, Mark Eben; Andersen, Carsten B; Sebring, Kristen; Zhou, Xianbo; Petroski, Robert; Limberis, James; Augustin, Martin; Chun, Lawrence E; Edwards, Thomas E; Peters, Marco; Tabatabaei, Ali

    2017-04-27

    A series of potent thienotriazolopyrimidinone-based PDE1 inhibitors was discovered. X-ray crystal structures of example compounds from this series in complex with the catalytic domain of PDE1B and PDE10A were determined, allowing optimization of PDE1B potency and PDE selectivity. Reduction of hERG affinity led to greater than a 3000-fold selectivity for PDE1B over hERG. 6-(4-Methoxybenzyl)-9-((tetrahydro-2H-pyran-4-yl)methyl)-8,9,10,11-tetrahydropyrido[4',3':4,5]thieno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidin-5(6H)-one was identified as an orally bioavailable and brain penetrating PDE1B enzyme inhibitor with potent memory-enhancing effects in a rat model of object recognition memory.

  6. Inhibition of serotonin transporters disrupts the enhancement of fear memory extinction by 3,4-methylenedioxymethamphetamine (MDMA).

    Science.gov (United States)

    Young, Matthew B; Norrholm, Seth D; Khoury, Lara M; Jovanovic, Tanja; Rauch, Sheila A M; Reiff, Collin M; Dunlop, Boadie W; Rothbaum, Barbara O; Howell, Leonard L

    2017-10-01

    3,4-Methylenedioxymethamphetamine (MDMA) persistently improves symptoms of post-traumatic stress disorder (PTSD) when combined with psychotherapy. Studies in rodents suggest that these effects can be attributed to enhancement of fear memory extinction. Therefore, MDMA may improve the effects of exposure-based therapy for PTSD, particularly in treatment-resistant patients. However, given MDMA's broad pharmacological profile, further investigation is warranted before moving to a complex clinical population. We aimed to inform clinical research by providing a translational model of MDMA's effect, and elucidating monoaminergic mechanisms through which MDMA enhances fear extinction. We explored the importance of monoamine transporters targeted by MDMA to fear memory extinction, as measured by reductions in conditioned freezing and fear-potentiated startle (FPS) in mice. Mice were treated with selective inhibitors of individual monoamine transporters prior to combined MDMA treatment and fear extinction training. MDMA enhanced the lasting extinction of FPS. Acute and chronic treatment with a 5-HT transporter (5-HTT) inhibitor blocked MDMA's effect on fear memory extinction. Acute inhibition of dopamine (DA) and norepinephrine (NE) transporters had no effect. 5-HT release alone did not enhance extinction. Blockade of MDMA's effect by 5-HTT inhibition also downregulated 5-HT 2A -mediated behavior, and 5-HT 2A antagonism disrupted MDMA's effect on extinction. We validate enhancement of fear memory extinction by MDMA in a translational behavioral model, and reveal the importance of 5-HTT and 5-HT 2A receptors to this effect. These observations support future clinical research of MDMA as an adjunct to exposure therapy, and provide important pharmacological considerations for clinical use in a population frequently treated with 5-HTT inhibitors.

  7. Neural mechanisms of reactivation-induced updating that enhance and distort memory.

    Science.gov (United States)

    St Jacques, Peggy L; Olm, Christopher; Schacter, Daniel L

    2013-12-03

    We remember a considerable number of personal experiences because we are frequently reminded of them, a process known as memory reactivation. Although memory reactivation helps to stabilize and update memories, reactivation may also introduce distortions if novel information becomes incorporated with memory. Here we used functional magnetic resonance imaging (fMRI) to investigate the neural mechanisms mediating reactivation-induced updating in memory for events experienced during a museum tour. During scanning, participants were shown target photographs to reactivate memories from the museum tour followed by a novel lure photograph from an alternate tour. Later, participants were presented with target and lure photographs and asked to determine whether the photographs showed a stop they visited during the tour. We used a subsequent memory analysis to examine neural recruitment during reactivation that was associated with later true and false memories. We predicted that the quality of reactivation, as determined by online ratings of subjective recollection, would increase subsequent true memories but also facilitate incorporation of the lure photograph, thereby increasing subsequent false memories. The fMRI results revealed that the quality of reactivation modulated subsequent true and false memories via recruitment of left posterior parahippocampal, bilateral retrosplenial, and bilateral posterior inferior parietal cortices. However, the timing of neural recruitment and the way in which memories were reactivated contributed to differences in whether memory reactivation led to distortions or not. These data reveal the neural mechanisms recruited during memory reactivation that modify how memories will be subsequently retrieved, supporting the flexible and dynamic aspects of memory.

  8. Enhancing Spatial Attention and Working Memory in Younger and Older Adults.

    Science.gov (United States)

    Rolle, Camarin E; Anguera, Joaquin A; Skinner, Sasha N; Voytek, Bradley; Gazzaley, Adam

    2017-09-01

    Daily experiences demand both focused and broad allocation of attention for us to interact efficiently with our complex environments. Many types of attention have shown age-related decline, although there is also evidence that such deficits may be remediated with cognitive training. However, spatial attention abilities have shown inconsistent age-related differences, and the extent of potential enhancement of these abilities remains unknown. Here, we assessed spatial attention in both healthy younger and older adults and trained this ability in both age groups for 5 hr over the course of 2 weeks using a custom-made, computerized mobile training application. We compared training-related gains on a spatial attention assessment and spatial working memory task to age-matched controls who engaged in expectancy-matched, active placebo computerized training. Age-related declines in spatial attention abilities were observed regardless of task difficulty. Spatial attention training led to improved focused and distributed attention abilities as well as improved spatial working memory in both younger and older participants. No such improvements were observed in either of the age-matched control groups. Note that these findings were not a function of improvements in simple response time, as basic motoric function did not change after training. Furthermore, when using change in simple response time as a covariate, all findings remained significant. These results suggest that spatial attention training can lead to enhancements in spatial working memory regardless of age.

  9. Enhancing Spatial Attention and Working Memory in Younger and Older Adults

    Science.gov (United States)

    Rolle, Camarin E.; Anguera, Joaquin A.; Skinner, Sasha N.; Voytek, Bradley; Gazzaley, Adam

    2018-01-01

    Daily experiences demand both focused and broad allocation of attention for us to interact efficiently with our complex environments. Many types of attention have shown age-related decline, although there is also evidence that such deficits may be remediated with cognitive training. However, spatial attention abilities have shown inconsistent age-related differences, and the extent of potential enhancement of these abilities remains unknown. Here, we assessed spatial attention in both healthy younger and older adults and trained this ability in both age groups for 5 hr over the course of 2 weeks using a custom-made, computerized mobile training application. We compared training-related gains on a spatial attention assessment and spatial working memory task to age-matched controls who engaged in expectancy-matched, active placebo computerized training. Age-related declines in spatial attention abilities were observed regardless of task difficulty. Spatial attention training led to improved focused and distributed attention abilities as well as improved spatial working memory in both younger and older participants. No such improvements were observed in either of the age-matched control groups. Note that these findings were not a function of improvements in simple response time, as basic motoric function did not change after training. Furthermore, when using change in simple response time as a covariate, all findings remained significant. These results suggest that spatial attention training can lead to enhancements in spatial working memory regardless of age. PMID:28654361

  10. Hormonal modulation of novelty processing in women: Enhanced under working memory load with high dehydroepiandrosterone-sulfate-to-dehydroepiandrosterone ratios.

    Science.gov (United States)

    do Vale, Sónia; Selinger, Lenka; Martins, João Martin; Bicho, Manuel; do Carmo, Isabel; Escera, Carles

    2016-11-10

    Several studies have suggested that dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEAS) may enhance working memory and attention, yet current evidence is still inconclusive. The balance between both forms of the hormone might be crucial regarding the effects that DHEA and DHEAS exert on the central nervous system. To test the hypothesis that higher DHEAS-to-DHEA ratios might enhance working memory and/or involuntary attention, we studied the DHEAS-to-DHEA ratio in relation to involuntary attention and working memory processing by recording the electroencephalogram of 22 young women while performing a working memory load task and a task without working memory load in an audio-visual oddball paradigm. DHEA and DHEAS were measured in saliva before each task. We found that a higher DHEAS-to-DHEA ratio was related to enhanced auditory novelty-P3 amplitudes during performance of the working memory task, indicating an increased processing of the distracter, while on the other hand there was no difference in the processing of the visual target. These results suggest that the balance between DHEAS and DHEA levels modulates involuntary attention during the performance of a task with cognitive load without interfering with the processing of the task-relevant visual stimulus. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Stress before extinction learning enhances and generalizes extinction memory in a predictive learning task.

    Science.gov (United States)

    Meir Drexler, Shira; Hamacher-Dang, Tanja C; Wolf, Oliver T

    2017-05-01

    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.

  12. Enhanced photomechanical response of a Ni-Ti shape memory alloy coated with polymer-based photothermal composites

    Science.gov (United States)

    Perez-Zúñiga, M. G.; Sánchez-Arévalo, F. M.; Hernández-Cordero, J.

    2017-10-01

    A simple way to enhance the activation of shape memory effects with light in a Ni-Ti alloy is demonstrated. Using polydimethylsiloxane-carbon nanopowder (PDMS+CNP) composites as coatings, the one-way shape memory effect (OWSME) of the alloy can be triggered using low power IR light from a laser diode. The PDMS+CNP coatings serve as photothermal materials capable to absorb light, and subsequently generate and dissipate heat in a highly efficient manner, thereby reducing the optical powers required for triggering the OWSME in the Ni-Ti alloy. Experimental results with a cantilever flexural test using both, bare Ni-Ti and coated samples, show that the PDMS+CNP coatings perform as thermal boosters, and therefore the temperatures required for phase transformation in the alloy can be readily obtained with low laser powers. It is also shown that the two-way shape memory effect (TWSME) can be set in the Ni-Ti alloy through cycling the TWSME by simply modulating the laser diode signal. This provides a simple means for training the material, yielding a light driven actuator capable to provide forces in the mN range. Hence, the use of photothermal coatings on Ni-Ti shape memory alloys may offer new possibilities for developing light-controlled smart actuators.

  13. Enhancing memory performance with rTMS in healthy and neurological subjects: the role of the right dorsolateral prefrontal cortex

    Directory of Open Access Journals (Sweden)

    Patrizia eTurriziani

    2012-04-01

    Full Text Available A debated question in the literature is the degree of anatomical and functional lateralization of the executive control processes subserved by the dorsolateral prefrontal cortex (DLPFC during recognition memory retrieval.We investigated if transient inhibition and excitation of the left and right DLPFC at retrieval by means of repetitive transcranial magnetic stimulation (rTMS modulate recognition memory performance in 100 healthy controls (HCs and in 8 patients with Mild Cognitive Impairment (MCI. Recognition memory tasks of faces, buildings and words were used in different experiments.rTMS-inhibition of the right DLPFC enhanced recognition memory of verbal and non verbal material in both HCs and MCIs. rTMS-excitation of the same region in HCs deteriorated memory performance.Bilateral recruitment of the DLPFC could represent a dysfunctional use of brain resources in recognition memory. Inhibitory rTMS of the right DLPFC may modulate the activity in this dysfunctional network enhancing function in HCs or restoring an adaptive equilibrium in MCI.

  14. A Chinese Chan-based lifestyle intervention improves memory of older adults

    Directory of Open Access Journals (Sweden)

    Agnes S. eChan

    2014-03-01

    Full Text Available This study aims to explore the potential benefits of a Chinese Chan-based lifestyle intervention on enhancing memory in older people with lower memory function. Forty-four aged 60 to 83 adults with various level of memory ability participated in the study. Their memories (including verbal and visual components were assessed before and after a 3-month intervention. The intervention consisted of 12 sessions, with one 90-minute session per week. The intervention involved components of adopting a special vegetarian diet, practicing a type of mind-body exercises and learning self-realization. Elderly with lower memory function at the baseline (i.e., their performance on standardized memory tests was within 25th percentile showed a significant memory improvement after the intervention. Their verbal and visual memory performance has showed 50% and 49% enhancement respectively. In addition, their improvement can be considered as a reliable and clinically significant change as reflected by their significant pre-post differences and reliable change indices. Such robust treatment effect was found to be specific to memory functions, but less influencing on the other cognitive functions. These preliminary encouraging results have shed some light on the potential applicability of the Chinese Chan-based lifestyle intervention as a method for enhancing memory in the elderly population.

  15. Enhanced Memory Consolidation Via Automatic Sound Stimulation During Non-REM Sleep.

    Science.gov (United States)

    Leminen, Miika M; Virkkala, Jussi; Saure, Emma; Paajanen, Teemu; Zee, Phyllis C; Santostasi, Giovanni; Hublin, Christer; Müller, Kiti; Porkka-Heiskanen, Tarja; Huotilainen, Minna; Paunio, Tiina

    2017-03-01

    Slow-wave sleep (SWS) slow waves and sleep spindle activity have been shown to be crucial for memory consolidation. Recently, memory consolidation has been causally facilitated in human participants via auditory stimuli phase-locked to SWS slow waves. Here, we aimed to develop a new acoustic stimulus protocol to facilitate learning and to validate it using different memory tasks. Most importantly, the stimulation setup was automated to be applicable for ambulatory home use. Fifteen healthy participants slept 3 nights in the laboratory. Learning was tested with 4 memory tasks (word pairs, serial finger tapping, picture recognition, and face-name association). Additional questionnaires addressed subjective sleep quality and overnight changes in mood. During the stimulus night, auditory stimuli were adjusted and targeted by an unsupervised algorithm to be phase-locked to the negative peak of slow waves in SWS. During the control night no sounds were presented. Results showed that the sound stimulation increased both slow wave (p = .002) and sleep spindle activity (p memory performance was compared between stimulus and control nights, we found a significant effect in word pair task but not in other memory tasks. The stimulation did not affect sleep structure or subjective sleep quality. We showed that the memory effect of the SWS-targeted individually triggered single-sound stimulation is specific to verbal associative memory. Moreover, the ambulatory and automated sound stimulus setup was promising and allows for a broad range of potential follow-up studies in the future. © Sleep Research Society 2017. Published by Oxford University Press [on behalf of the Sleep Research Society].

  16. Angiotensin IV and LVV-haemorphin 7 enhance spatial working memory in rats: effects on hippocampal glucose levels and blood flow.

    Science.gov (United States)

    De Bundel, Dimitri; Smolders, Ilse; Yang, Rui; Albiston, Anthony L; Michotte, Yvette; Chai, Siew Yeen

    2009-07-01

    The IRAP ligands Angiotensin IV (Ang IV) and LVV-haemorphin 7 (LVV-H7) enhance performance in a range of memory paradigms in normal rats and ameliorate memory deficits in rat models for amnesia. The mechanism by which these peptides facilitate memory remains to be elucidated. In recent in vitro experiments, we demonstrated that Ang IV and LVV-H7 potentiate activity-evoked glucose uptake into hippocampal neurons. This raises the possibility that IRAP ligands may facilitate memory in hippocampus-dependent tasks through enhancement of hippocampal glucose uptake. Acute intracerebroventricular (i.c.v.) administration of 1nmol Ang IV or 0.1nmol LVV-H7 in 3 months-old Sprague-Dawley rats enhanced spatial working memory in the plus maze spontaneous alternation task. Extracellular hippocampal glucose levels were monitored before, during and after behavioral testing using in vivo microdialysis. Extracellular hippocampal glucose levels decreased significantly to about 70% of baseline when the animals explored the plus maze, but remained constant when the animals were placed into a novel control chamber. Ang IV and LVV-H7 did not significantly alter hippocampal glucose levels compared to control animals in the plus maze or control chamber. Both peptides had no effect on hippocampal blood flow as determined by laser Doppler flowmetry, excluding that either peptide increased the hippocampal supply of glucose. We demonstrated for the first time that Ang IV and LVV-H7 enhance spatial working memory in the plus maze spontaneous alternation task but no in vivo evidence was found for enhanced hippocampal glucose uptake or blood flow.

  17. Time-limited effects of emotional arousal on item and source memory.

    Science.gov (United States)

    Wang, Bo; Sun, Bukuan

    2015-01-01

    Two experiments investigated the time-limited effects of emotional arousal on consolidation of item and source memory. In Experiment 1, participants memorized words (items) and the corresponding speakers (sources) and then took an immediate free recall test. Then they watched a neutral, positive, or negative video 5, 35, or 50 min after learning, and 24 hours later they took surprise memory tests. Experiment 2 was similar to Experiment 1 except that (a) a reality monitoring task was used; (b) elicitation delays of 5, 30, and 45 min were used; and (c) delayed memory tests were given 60 min after learning. Both experiments showed that, regardless of elicitation delay, emotional arousal did not enhance item recall memory. Second, both experiments showed that negative arousal enhanced delayed item recognition memory only at the medium elicitation delay, but not in the shorter or longer delays. Positive arousal enhanced performance only in Experiment 1. Third, regardless of elicitation delay, emotional arousal had little effect on source memory. These findings have implications for theories of emotion and memory, suggesting that emotion effects are contingent upon the nature of the memory task and elicitation delay.

  18. State of the art on targeted memory reactivation: Sleep your way to enhanced cognition.

    Science.gov (United States)

    Schouten, Daphne I; Pereira, Sofia I R; Tops, Mattie; Louzada, Fernando M

    2017-04-01

    Targeted memory reactivation is a fairly simple technique that has the potential to influence the course of memory formation through application of cues during sleep. Studies have shown that cueing memory during sleep can lead to either an enhanced or decreased representation of the information encoded in the targeted networks, depending on experimental variations. The effects have been associated with sleep parameters and accompanied by activation of memory related brain areas. The findings suggest a causal role of neuronal replay in memory consolidation and provide evidence for the active system consolidation hypothesis. However, the observed inconsistencies across studies suggest that further research is warranted regarding the underlying neural mechanisms and optimal conditions for the application of targeted memory reactivation. The goal of the present review is to integrate the currently available experimental data and to provide an overview of this technique's limitations and pitfalls, as well as its potential applications in everyday use and clinical treatment. Exploring the open questions herein identified should lead to insight into safer and more effective ways of adjusting memory representations to better suit individual needs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Sildenafil, a selective phosphodiesterase type 5 inhibitor, enhances memory reconsolidation of an inhibitory avoidance task in mice.

    Science.gov (United States)

    Boccia, M M; Blake, M G; Krawczyk, M C; Baratti, C M

    2011-07-07

    Intracellular levels of the second messengers cAMP and cGMP are maintained through a balance between production, carried out by adenyl cyclase (AC) and guanylyl cyclase (GC), and degradation, carried out by phosphodiesterases (PDEs). Recently, PDEs have gained increased attention as potential new targets for cognition enhancement, with particular reference to phosphodiesterase type 5 (PDE5A). It is accepted that once consolidation is completed memory becomes permanent, but it has also been suggested that reactivation (memory retrieval) of the original memory makes it sensitive to the same treatments that affect memory consolidation when given after training. This new period of sensitivity coined the term reconsolidation. Sildenafil (1, 3, and 10mg/kg, ip), a cGMP-PDE5 inhibitor, facilitated retention performance of a one-trial step-through inhibitory avoidance task, when administered to CF-1 male mice immediately after retrieval. The effects of sildenafil (1mg/kg, ip) were time-dependent, long-lasting and inversely correlated with memory age. The administration of sildenafil (1mg/kg, ip) 30 min prior to the 2nd retention test did not affect retention of mice given post-retrieval injections of either vehicle or sildenafil (1mg/kg, ip). Finally, an enhancement of retention was also observed in CF-1 female mice receiving sildenafil (1mg/kg, ip) immediately, but not 180 min after retrieval. In the present paper we reported for the first time that systemic administration of sildenafil after memory reactivation enhances retention performance of the original learning. Our results indirectly point out cGMP, a component of the NO/cGMP/PKG pathway, as a necessary factor for memory reconsolidation. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Representational Account of Memory: Insights from Aging and Synesthesia.

    Science.gov (United States)

    Pfeifer, Gaby; Ward, Jamie; Chan, Dennis; Sigala, Natasha

    2016-12-01

    The representational account of memory envisages perception and memory to be on a continuum rather than in discretely divided brain systems [Bussey, T. J., & Saksida, L. M. Memory, perception, and the ventral visual-perirhinal-hippocampal stream: Thinking outside of the boxes. Hippocampus, 17, 898-908, 2007]. We tested this account using a novel between-group design with young grapheme-color synesthetes, older adults, and young controls. We investigated how the disparate sensory-perceptual abilities between these groups translated into associative memory performance for visual stimuli that do not induce synesthesia. ROI analyses of the entire ventral visual stream showed that associative retrieval (a pair-associate retrieved in the absence of a visual stimulus) yielded enhanced activity in young and older adults' visual regions relative to synesthetes, whereas associative recognition (deciding whether a visual stimulus was the correct pair-associate) was characterized by enhanced activity in synesthetes' visual regions relative to older adults. Whole-brain analyses at associative retrieval revealed an effect of age in early visual cortex, with older adults showing enhanced activity relative to synesthetes and young adults. At associative recognition, the group effect was reversed: Synesthetes showed significantly enhanced activity relative to young and older adults in early visual regions. The inverted group effects observed between retrieval and recognition indicate that reduced sensitivity in visual cortex (as in aging) comes with increased activity during top-down retrieval and decreased activity during bottom-up recognition, whereas enhanced sensitivity (as in synesthesia) shows the opposite pattern. Our results provide novel evidence for the direct contribution of perceptual mechanisms to visual associative memory based on the examples of synesthesia and aging.

  1. Associative Learning during Early Adulthood Enhances Later Memory Retention in Honeybees

    Science.gov (United States)

    Arenas, Andrés; Fernández, Vanesa M.; Farina, Walter M.

    2009-01-01

    Background Cognitive experiences during the early stages of life play an important role in shaping the future behavior in mammals but also in insects, in which precocious learning can directly modify behaviors later in life depending on both the timing and the rearing environment. However, whether olfactory associative learning acquired early in the adult stage of insects affect memorizing of new learning events has not been studied yet. Methodology Groups of adult honeybee workers that experienced an odor paired with a sucrose solution 5 to 8 days or 9 to 12 days after emergence were previously exposed to (i) a rewarded experience through the offering of scented food, or (ii) a non-rewarded experience with a pure volatile compound in the rearing environment. Principal Findings Early rewarded experiences (either at 1–4 or 5–8 days of adult age) enhanced retention performance in 9–12-day-conditioned bees when they were tested at 17 days of age. The highest retention levels at this age, which could not be improved with prior rewarded experiences, were found for memories established at 5–8 days of adult age. Associative memories acquired at 9–12 days of age showed a weak effect on retention for some pure pre-exposed volatile compounds; whereas the sole exposure of an odor at any younger age did not promote long-term effects on learning performance. Conclusions The associative learning events that occurred a few days after adult emergence improved memorizing in middle-aged bees. In addition, both the timing and the nature of early sensory inputs interact to enhance retention of new learning events acquired later in life, an important matter in the social life of honeybees. PMID:19956575

  2. Associative learning during early adulthood enhances later memory retention in honeybees.

    Directory of Open Access Journals (Sweden)

    Andrés Arenas

    Full Text Available BACKGROUND: Cognitive experiences during the early stages of life play an important role in shaping the future behavior in mammals but also in insects, in which precocious learning can directly modify behaviors later in life depending on both the timing and the rearing environment. However, whether olfactory associative learning acquired early in the adult stage of insects affect memorizing of new learning events has not been studied yet. METHODOLOGY: Groups of adult honeybee workers that experienced an odor paired with a sucrose solution 5 to 8 days or 9 to 12 days after emergence were previously exposed to (i a rewarded experience through the offering of scented food, or (ii a non-rewarded experience with a pure volatile compound in the rearing environment. PRINCIPAL FINDINGS: Early rewarded experiences (either at 1-4 or 5-8 days of adult age enhanced retention performance in 9-12-day-conditioned bees when they were tested at 17 days of age. The highest retention levels at this age, which could not be improved with prior rewarded experiences, were found for memories established at 5-8 days of adult age. Associative memories acquired at 9-12 days of age showed a weak effect on retention for some pure pre-exposed volatile compounds; whereas the sole exposure of an odor at any younger age did not promote long-term effects on learning performance. CONCLUSIONS: The associative learning events that occurred a few days after adult emergence improved memorizing in middle-aged bees. In addition, both the timing and the nature of early sensory inputs interact to enhance retention of new learning events acquired later in life, an important matter in the social life of honeybees.

  3. Enhancement of declarative memory associated with emotional content in a Brazilian sample

    Directory of Open Access Journals (Sweden)

    Frank J.E.

    2000-01-01

    Full Text Available Several studies have documented that emotional arousal may enhance long-term memory. This is an adaptation of a paradigm previously used in North American and European samples in investigations of the influence of emotion on long-term retention. A sample of 46 healthy adults of high and low educational levels watched a slide presentation of stories. A randomly assigned group watched a story with an arousing content and another group watched a neutral story. The stories were matched for structure and comprehensibility and the set and order of the 11 slides were the same in both conditions. Immediately after viewing the slide presentation, the participants were asked to rate the emotionality of the narrative. The arousing narrative was rated as being more emotional than the neutral narrative (t (44 = -3.6, P<0.001. Ten days later subjects were asked to remember the story and answer a multiple-choice questionnaire about it. The subjects who watched the arousing story had higher scores in the free recall measure (t (44 = -2.59, P<0.01. There were no differences between groups in the multiple-choice test of recognition memory (t (44 = 0.26. These findings confirm that an emotional arousing content enhances long-term declarative memory and indicate the possibility of applying this instrument to clinical samples of various cultural backgrounds.

  4. Methyl jasmonate enhances memory performance through inhibition of oxidative stress and acetylcholinesterase activity in mice.

    Science.gov (United States)

    Eduviere, Anthony T; Umukoro, S; Aderibigbe, Adegbuyi O; Ajayi, Abayomi M; Adewole, Folashade A

    2015-07-01

    Current research effort focuses on the development of safer natural compounds with multipronged mechanisms of action that could be used to ameliorate memory deficits in patients with Alzheimer's disease, as cure for the disease still remains elusive. In this study, we evaluated the effect of methyl jasmonate (MJ), a naturally occurring bioactive compound on memory, acetylcholinesterase activity and biomarkers of oxidative stress in mice. Male Swiss mice were treated with intraperitoneal injection of MJ (10-40 mg/kg) alone or in combination with scopolamine (3mg/kg) once daily for 7 days. Thirty minutes after the last treatment, memory functions were assessed using Y-maze and object recognition tests. Thereafter, acetylcholinesterase activity and levels of biomarkers of oxidative stress were assessed in mice brains using standard biochemical procedures. MJ significantly enhanced memory performance and reversed scopolamine-induced cognitive impairment in mice. MJ demonstrated significant inhibition of acetylcholinesterase activity suggesting increased cholinergic neurotransmission. It further decreased malondialdehyde concentrations in mouse brain indicating antioxidant activity. Moreover, MJ significantly increased glutathione levels and activity of antioxidant enzymes (catalase and superoxide dismutase) in mice brains. The increased oxidative stress; evidenced by elevated levels of malondialdehyde and decreased antioxidant defense systems in scopolamine-treated mice was attenuated by MJ. The results of this study suggest that MJ may be useful in conditions associated with memory dysfunctions or age-related cognitive decline. The positive effect of MJ on memory may be related to inhibition of oxidative stress and enhancement of cholinergic neurotransmission through inhibition of acetylcholinesterase activity. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Acupuncture reduces memory impairment and oxidative stress and enhances cholinergic function in an animal model of alcoholism.

    Science.gov (United States)

    Phunchago, Nattaporn; Wattanathorn, Jintanaporn; Chaisiwamongkol, Kowit; Muchimapura, Supaporn; Thukham-Mee, Wipawee

    2015-02-01

    Currently, the therapeutic strategy against memory deficit induced by alcoholism is not satisfactory and is expensive. Therefore, an effective, low-cost strategy is required. On the basis of the memory-enhancing effect of stimulation of the HT7 acupoint, we aimed to determine whether acupuncture at the HT7 acupoint can reduce alcoholism-induced memory impairment. The possible underlying mechanism was also explored. Alcoholism was induced in male Wistar rats weighing 180-220 g. The alcoholic rats received either acupuncture at HT7 or sham acupuncture for 1 minute bilaterally once daily for 14 days. Their spatial memory was assessed after 1 day, 7 days, and 14 days of treatment. At the end of the study, the malondialdehyde level and the activities of catalase, superoxide dismutase, glutathione peroxidase, and acetylcholinesterase enzymes in the hippocampus were determined using colorimetric assays. The results showed that acupuncture at HT7 significantly decreased the acetylcholinesterase activity and the malondialdehyde level, but increased the activities of catalase, superoxide dismutase, and glutathione peroxidase in the hippocampus. These results suggest that acupuncture at HT7 can effectively reduce the alcoholism-induced memory deficit. However, further studies concerning the detailed relationships between the location of the HT7 acupoint and the changes in the observed parameters are required. Copyright © 2015. Published by Elsevier B.V.

  6. Focusing on food during lunch enhances lunch memory and decreases later snack intake.

    Science.gov (United States)

    Higgs, Suzanne; Donohoe, Jessica E

    2011-08-01

    We investigated whether eating lunch mindfully, in contrast to eating with distractions or no particular focus, reduces later snack intake and if this is related to a measure of meal memory. The design was between-subjects with three conditions. Twenty-nine female undergraduate students either ate a fixed lunch while (1) focusing on the sensory characteristics of the food as they ate (food focus group), (2) reading a newspaper article about food (food thoughts control group) or (3) in the absence of any secondary task (neutral control group). Cookie intake later that afternoon was measured as well as rated vividness of memory of the lunch. Participants ate significantly fewer cookies in the food focus group than in both the food thoughts control group or the neutral control group. Rated appetite before the snack session was lower in the food focus group than in the other two groups and rated vividness of lunch memory was higher. Rated vividness of lunch memory was negatively correlated with snack intake. These results suggest that enhancing meal memory by paying attention to food while eating can reduce later intake and are consistent with the suggestion that memory plays an important role in appetite control. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Enhancement of Spatial Learning-Memory in Developing Rats via Mozart Music

    Institute of Scientific and Technical Information of China (English)

    Jian-Gao Yao; Yang Xia; Sheng-Jun Dai; Guang-Zhan Fang; Hua Guo; De-Zhong Yao

    2009-01-01

    This paper studies the effect of musical stimulations on the capability of the spatial learning-memory in developing rats by behavioral and electro-physiological techniques.Rats,which are exposed to Mozart's Sonata for Two Pianos in D Major,complete learning tasks of the Moriss water maze with significantly shorter latencies,and the power spectrum of alpha band of electrohippocampogram (EHG) significantly increase,compared with the control rats and rats exposed to the horror music.The results indicate that if given the stimulation of Mozart music in the developmental period of the auditory cortex,the capability of the spatial learning-memory can be significantly changed.The enhancement of alpha band of EHG may be related to the change of this function mainly.

  8. Cyclic GMP-mediated memory enhancement in the object recognition test by inhibitors of phosphodiesterase-2 in mice.

    Science.gov (United States)

    Lueptow, Lindsay M; Zhan, Chang-Guo; O'Donnell, James M

    2016-02-01

    Cyclic nucleotide phosphodiesterase-2 (PDE2) is a potential therapeutic target for the treatment of cognitive dysfunction. Using the object recognition test (ORT), this study assessed the effects of two PDE2 inhibitors, Bay 60-7550 and ND7001, on learning and memory, and examined underlying mechanisms. To assess the role of PDE2 inhibition on phases of memory, Bay 60-7550 (3 mg/kg) was administered: 30 min prior to training; 0, 1, or 3 h after training; or 30 min prior to recall testing. To assess cyclic nucleotide involvement in PDE2 inhibitor-enhanced memory consolidation, either the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 20 mg/kg; intraperitoneal (IP)), soluble guanylyl cyclase inhibitor 1H-[-1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ; 20 mg/kg; IP), protein kinase G inhibitor KT5823 (2.5 μg; intracerebroventricular (ICV)), or protein kinase A inhibitor H89 (1 μg; ICV) was administered 30 min prior to the PDE2 inhibitor Bay 60-7550 (3 mg/kg) or ND7001 (3 mg/kg). Changes in the phosphorylation of 3'5'-cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) at Ser-133 and vasodilator-stimulated phosphoprotein (VASP) at Ser-239 were determined to confirm activation of cAMP and 3'5'-cyclic guanosine monophosphate (cGMP) signaling. Bay 60-7550 (3 mg/kg) enhanced memory of mice in the ORT when given 30 min prior to training, immediately after training, or 30 min prior to recall. Inhibitors of the cGMP pathway blocked the memory-enhancing effects of both Bay 60-7550 (3 mg/kg) and ND7001 (3 mg/kg) on early consolidation processes. Bay 60-7550 (3 mg/kg) enhanced phosphorylation of CREB and VASP, both targets of cGMP-dependent protein kinase (PKG). These results confirm a potential of PDE2, or components of its signaling pathway, as a therapeutic target for drug discovery focused on restoring memory function.

  9. Histone Deacetylase Inhibition Induces Odor Preference Memory Extension and Maintains Enhanced AMPA Receptor Expression in the Rat Pup Model

    Science.gov (United States)

    Bhattacharya, Sriya; Mukherjee, Bandhan; Doré, Jules J. E.; Yuan, Qi; Harley, Carolyn W.; McLean, John H.

    2017-01-01

    Histone deacetylase (HDAC) plays a role in synaptic plasticity and long-term memory formation. We hypothesized that trichostatin-A (TSA), an HDAC inhibitor, would promote long-term odor preference memory and maintain enhanced GluA1 receptor levels that have been hypothesized to support memory. We used an early odor preference learning model in…

  10. Generation and memory for contextual detail.

    Science.gov (United States)

    Mulligan, Neil W

    2004-07-01

    Generation enhances item memory but may not enhance other aspects of memory. In 12 experiments, the author investigated the effect of generation on context memory, motivated in part by the hypothesis that generation produces a trade-off in encoding item and contextual information. Participants generated some study words (e.g., hot-c__) and read others (e.g., hot-cold). Generation consistently enhanced item memory but did not enhance context memory. More specifically, generation disrupted context memory for the color of the target word but did not affect context memory for location, background color, and cue-word color. The specificity of the negative generation effect in context memory argues against a general item-context trade-off. A processing account of generation meets greater success. In addition, the results provide no evidence that generation enhances recollection of contextual details. Copyright 2004 APA, all rights reserved

  11. Epobis is a Nonerythropoietic and Neuroprotective Agonist of the Erythropoietin Receptor with Anti-Inflammatory and Memory Enhancing Effects

    DEFF Research Database (Denmark)

    Dmytriyeva, Oksana; Pankratova, Stanislava; Korshunova, Irina

    2016-01-01

    , but systemic administration of Epobis in rats delays the clinical signs of experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis, and the peptide has long-term, but not short-term, effects on working memory, detected as an improved social memory 3 days after administration....... These data reveal Epobis to be a nonerythropoietic and neuroprotective EPO receptor agonist with anti-inflammatory and memory enhancing properties....

  12. Enhanced Associative Memory for Colour (but Not Shape or Location) in Synaesthesia

    Science.gov (United States)

    Pritchard, Jamie; Rothen, Nicolas; Coolbear, Daniel; Ward, Jamie

    2013-01-01

    People with grapheme-colour synaesthesia have been shown to have enhanced memory on a range of tasks using both stimuli that induce synaesthesia (e.g. words) and, more surprisingly, stimuli that do not (e.g. certain abstract visual stimuli). This study examines the latter by using multi-featured stimuli consisting of shape, colour and location…

  13. Emotionally Negative Pictures Enhance Gist Memory

    OpenAIRE

    Bookbinder, S. H.; Brainerd, C. J.

    2016-01-01

    In prior work on how true and false memory are influenced by emotion, valence and arousal have often been conflated. Thus, it is difficult to say which specific effects are due to valence and which are due to arousal. In the present research, we used a picture-memory paradigm that allowed emotional valence to be manipulated with arousal held constant. Negatively-valenced pictures elevated both true and false memory, relative to positive and neutral pictures. Conjoint recognition modeling reve...

  14. Positive emotion can protect against source memory impairment.

    Science.gov (United States)

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

    2015-01-01

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

  15. Enhancing memory self-efficacy during menopause through a group memory strategies program.

    Science.gov (United States)

    Unkenstein, Anne E; Bei, Bei; Bryant, Christina A

    2017-05-01

    Anxiety about memory during menopause can affect quality of life. We aimed to improve memory self-efficacy during menopause using a group memory strategies program. The program was run five times for a total of 32 peri- and postmenopausal women, age between 47 and 60 years, recruited from hospital menopause and gynecology clinics. The 4-week intervention consisted of weekly 2-hour sessions, and covered how memory works, memory changes related to ageing, health and lifestyle factors, and specific memory strategies. Memory contentment (CT), reported frequency of forgetting (FF), use of memory strategies, psychological distress, and attitude toward menopause were measured. A double-baseline design was applied, with outcomes measured on two baseline occasions (1-month prior [T1] and in the first session [T2]), immediately postintervention (T3), and 3-month postintervention (T4). To describe changes in each variable between time points paired sample t tests were conducted. Mixed-effects models comparing the means of random slopes from T2 to T3 with those from T1 to T2 were conducted for each variable to test for treatment effects. Examination of the naturalistic changes in outcome measures from T1 to T2 revealed no significant changes (all Ps > 0.05). CT, reported FF, and use of memory strategies improved significantly more from T2 to T3, than from T1 to T2 (all Ps attitude toward menopause nor psychological distress improved significantly more postintervention than during the double-baseline (all Ps > 0.05). Improvements in reported CT and FF were maintained after 3 months. The use of group interventions to improve memory self-efficacy during menopause warrants continued evaluation.

  16. Glucose administration prior to a divided attention task improves tracking performance but not word recognition: evidence against differential memory enhancement?

    Science.gov (United States)

    Scholey, Andrew B; Sünram-Lea, Sandra I; Greer, Joanna; Elliott, Jade; Kennedy, David O

    2009-01-01

    The cognition-enhancing effects of glucose administration to humans have been well-documented; however, it remains unclear whether this effect preferentially targets episodic memory or other cognitive domains. The effect of glucose on the allocation of attentional resources during memory encoding was assessed using a sensitive dual-attention paradigm. One hundred and twenty volunteers (mean age 21.60, SD 4.89, 77 females) took part in this randomised, double-blind, placebo-controlled, parallel groups study where each consumed a 25-g glucose drink or a placebo. Half of the participants in each drink condition attempted to track a moving on-screen target during auditory word presentation. The distance between the cursor and the tracking target was used as an index of attentional cost during encoding. Effects of drink and tracking on recognition memory and drink on tracking performance were assessed. Self-rated appetite and mood were co-monitored. Co-performing the tracking task significantly impaired memory performance irrespective of drink condition. In the placebo-tracking condition, there was a cost to tracking manifest as greater deviation from target during and immediately following word presentation. Compared with placebo, the glucose drink significantly improved tracking performance during encoding. There were significant time-related changes in thirst and alertness ratings but these were not differentially affected by drink or tracking conditions. Tracking but not memory was enhanced by glucose. This finding suggests that, under certain task conditions, glucose administrations does not preferentially enhance memory performance. One mechanism through which glucose acts as a cognition enhancer is through allowing greater allocation of attentional resources.

  17. Emotionally enhanced memory for negatively arousing words: storage or retrieval advantage?

    Science.gov (United States)

    Nadarevic, Lena

    2017-12-01

    People typically remember emotionally negative words better than neutral words. Two experiments are reported that investigate whether emotionally enhanced memory (EEM) for negatively arousing words is based on a storage or retrieval advantage. Participants studied non-word-word pairs that either involved negatively arousing or neutral target words. Memory for these target words was tested by means of a recognition test and a cued-recall test. Data were analysed with a multinomial model that allows the disentanglement of storage and retrieval processes in the present recognition-then-cued-recall paradigm. In both experiments the multinomial analyses revealed no storage differences between negatively arousing and neutral words but a clear retrieval advantage for negatively arousing words in the cued-recall test. These findings suggest that EEM for negatively arousing words is driven by associative processes.

  18. Exogenous hydrogen sulfide eliminates spatial memory retrieval impairment and hippocampal CA1 LTD enhancement caused by acute stress via promoting glutamate uptake.

    Science.gov (United States)

    He, Jin; Guo, Ruixian; Qiu, Pengxin; Su, Xingwen; Yan, Guangmei; Feng, Jianqiang

    2017-05-14

    Acute stress impairs the hippocampus-dependent spatial memory retrieval, and its synaptic mechanisms are associated with hippocampal CA1 long-term depression (LTD) enhancement in the adult rats. Endogenous hydrogen sulfide (H 2 S) is recognized as a novel gasotransmitter and has the neural protective roles. However, very little attention has been paid to understanding the effects of H 2 S on spatial memory retrieval impairment. We observed the protective effects of NaHS (a donor of H 2 S) against spatial memory retrieval impairment caused by acute stress and its synaptic mechanisms. Our results showed that NaHS abolished spatial memory retrieval impairment and hippocampal CA1 LTD enhancement caused by acute stress, but not by glutamate transporter inhibitor l-trans-pyrrolidine-2,4-dicarboxylic (tPDC), indicating that the activation of glutamate transporters is necessary for exogenous H 2 S to exert its roles. Moreover, NaHS restored the decreased glutamate uptake in the hippocampal CA1 synaptosomal fraction caused by acute stress. Dithiothreitol (DTT, a disulfide reducing agent) abolished a decrease in the glutamate uptake caused by acute stress, and NaHS eradicated the decreased glutamate uptake caused by 5,5'-dithio-bis(2-nitrobenzoic)acid (DTNB, a thiol oxidizing agent), collectively, revealing that exogenous H 2 S increases glutamate uptake by reducing disulfide bonds of the glutamate transporters. Additionally, NaHS inhibited the increased expression level of phosphorylated c-Jun-N-terminal kinase (JNK) in the hippocampal CA1 region caused by acute stress. The JNK inhibitor SP600125 eliminated spatial memory retrieval impairment, hippocampal CA1 LTD enhancement and the decreased glutamate uptake caused by acute stress, indicating that exogenous H 2 S exerts these roles by inhibiting the activation of JNK signaling pathway. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. Heart rate response to post-learning stress predicts memory consolidation.

    Science.gov (United States)

    Larra, Mauro F; Schulz, André; Schilling, Thomas M; Ferreira de Sá, Diana S; Best, Daniel; Kozik, Bartlomiej; Schächinger, Hartmut

    2014-03-01

    Stressful experiences are often well remembered, an effect that has been explained by beta-adrenergic influences on memory consolidation. Here, we studied the impact of stress induced heart rate (HR) responses on memory consolidation in a post-learning stress paradigm. 206 male and female participants saw 52 happy and angry faces immediately before being exposed to the Cold Pressor Test or a non-stressful control procedure. Memory for the faces and their respective expression was tested twice, after 30 min and on the next day. High HR responders (in comparison to low HR responders as well as to the non-stressful control group) showed enhanced recognition memory one day after learning. Our results show that beta-adrenergic activation elicited shortly after learning enhances memory consolidation and that the stress induced HR response is a predictor for this effect. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Nitride coating enhances endothelialization on biomedical NiTi shape memory alloy

    Energy Technology Data Exchange (ETDEWEB)

    Ion, Raluca [University of Bucharest, Department of Biochemistry and Molecular Biology, 91-95 Spl. Independentei, 050095 Bucharest (Romania); Luculescu, Catalin [National Institute for Laser, Plasma and Radiation Physics, 409 Atomistilor, P.O. Box MG-36, 077125 Magurele-Bucharest (Romania); Cimpean, Anisoara, E-mail: anisoara.cimpean@bio.unibuc.ro [University of Bucharest, Department of Biochemistry and Molecular Biology, 91-95 Spl. Independentei, 050095 Bucharest (Romania); Marx, Philippe [AMF Company, Route de Quincy, 18120 Lury-sur-Arnon (France); Gordin, Doina-Margareta; Gloriant, Thierry [INSA Rennes, UMR CNRS 6226 ISCR, 20 Avenue des Buttes de Coësmes, 35708 Rennes Cedex 7 (France)

    2016-05-01

    Surface nitriding was demonstrated to be an effective process for improving the biocompatibility of implantable devices. In this study, we investigated the benefits of nitriding the NiTi shape memory alloy for vascular stent applications. Results from cell experiments indicated that, compared to untreated NiTi, a superficial gas nitriding treatment enhanced the adhesion of human umbilical vein endothelial cells (HUVECs), cell spreading and proliferation. This investigation provides data to demonstrate the possibility of improving the rate of endothelialization on NiTi by means of nitride coating. - Highlights: • Gas nitriding process of NiTi is competent to promote cell spreading. • Surface nitriding of NiTi is able to stimulate focal adhesion formation and cell proliferation. • Similar expression pattern of vWf and eNOS was exhibited by bare and nitrided NiTi. • Gas nitriding treatment of NiTi shows promise for better in vivo endothelialization.

  1. Not all attention orienting is created equal: recognition memory is enhanced when attention orienting involves distractor suppression.

    Science.gov (United States)

    Markant, Julie; Worden, Michael S; Amso, Dima

    2015-04-01

    Learning through visual exploration often requires orienting of attention to meaningful information in a cluttered world. Previous work has shown that attention modulates visual cortex activity, with enhanced activity for attended targets and suppressed activity for competing inputs, thus enhancing the visual experience. Here we examined the idea that learning may be engaged differentially with variations in attention orienting mechanisms that drive eye movements during visual search and exploration. We hypothesized that attention orienting mechanisms that engaged suppression of a previously attended location would boost memory encoding of the currently attended target objects to a greater extent than those that involve target enhancement alone. To test this hypothesis we capitalized on the classic spatial cueing task and the inhibition of return (IOR) mechanism (Posner, 1980; Posner, Rafal, & Choate, 1985) to demonstrate that object images encoded in the context of concurrent suppression at a previously attended location were encoded more effectively and remembered better than those encoded without concurrent suppression. Furthermore, fMRI analyses revealed that this memory benefit was driven by attention modulation of visual cortex activity, as increased suppression of the previously attended location in visual cortex during target object encoding predicted better subsequent recognition memory performance. These results suggest that not all attention orienting impacts learning and memory equally. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Hippocampal Arc (Arg3.1) expression is induced by memory recall and required for memory reconsolidation in trace fear conditioning.

    Science.gov (United States)

    Chia, Chester; Otto, Tim

    2013-11-01

    Mounting evidence suggests that long-lasting, protein synthesis-dependent changes in synaptic strength accompany both the initial acquisition and subsequent recall of specific memories. Within brain areas thought to be important for learning and memory, including the hippocampus, learning-related plasticity is likely mediated in part by NMDA receptor activation and experience-dependent changes in gene expression. In the present study, we examined the role of activity-regulated cytoskeletal-associated protein (Arc/Arg3.1) expression in the acquisition, recall, and reconsolidation of memory in a trace fear conditioning paradigm. First, we show that the expression of Arc protein in ventral hippocampus (VH) is dramatically enhanced by memory recall 24h after the acquisition of trace fear conditioning, and that both memory recall and the associated recall-induced enhancement of Arc expression are blocked by pre-training administration of 2-amino-5-phosphonovaleric acid (APV). Next, we show that while infusion of Arc antisense oligodeoxynucleotides (ODNs) into VH prior to testing had little effect on memory recall, it significantly reduced both Arc protein expression and freezing behavior during subsequent testing sessions. Collectively, these results suggest that Arc/Arg3.1 protein plays an important functional role in both the initial acquisition of hippocampal-dependent memory and the reconsolidation of these memories after recall. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Test-Enhanced Learning of Natural Concepts: Effects on Recognition Memory, Classification, and Metacognition

    Science.gov (United States)

    Jacoby, Larry L.; Wahlheim, Christopher N.; Coane, Jennifer H.

    2010-01-01

    Three experiments examined testing effects on learning of natural concepts and metacognitive assessments of such learning. Results revealed that testing enhanced recognition memory and classification accuracy for studied and novel exemplars of bird families on immediate and delayed tests. These effects depended on the balance of study and test…

  4. Multi-Valued Associative Memory Neural Network

    Institute of Scientific and Technical Information of China (English)

    修春波; 刘向东; 张宇河

    2003-01-01

    A novel learning method for multi-valued associative memory network is introduced, which is based on Hebb rule, but utilizes more information. According to the current probe vector, the connection weights matrix could be chosen dynamically. Double-valued and multi-valued associative memory are all realized in our simulation experiment. The experimental results show that the method could enhance the associative success rate.

  5. Spatial vision is superior in musicians when memory plays a role.

    Science.gov (United States)

    Weiss, Atalia H; Biron, Tali; Lieder, Itay; Granot, Roni Y; Ahissar, Merav

    2014-08-21

    Musicians' perceptual advantage in the acoustic domain is well established. Recent studies show that musicians' verbal working memory is also superior. Additionally, some studies report that musicians' visuospatial skills are enhanced although others failed to find this enhancement. We now examined whether musicians' spatial vision is superior, and if so, whether this superiority reflects refined visual skills or a general superiority of working memory. We examined spatial frequency discrimination among musicians and nonmusician university students using two presentation conditions: simultaneous (spatial forced choice) and sequential (temporal forced choice). Musicians' performance was similar to that of nonmusicians in the simultaneous condition. However, their performance in the sequential condition was superior, suggesting an advantage only when stimuli need to be retained, i.e., working memory. Moreover, the two groups showed a different pattern of correlations: Musicians' visual thresholds were correlated, and neither was correlated with their verbal memory. By contrast, among nonmusicians, the visual thresholds were not correlated, but sequential thresholds were correlated with verbal memory scores, suggesting that a general working memory component limits their performance in this condition. We propose that musicians' superiority in spatial frequency discrimination reflects an advantage in a domain-general aspect of working memory rather than a general enhancement in spatial-visual skills. © 2014 ARVO.

  6. Privacy of a lossy bosonic memory channel

    Energy Technology Data Exchange (ETDEWEB)

    Ruggeri, Giovanna [Dipartimento di Fisica, Universita di Lecce, I-73100 Lecce (Italy)]. E-mail: ruggeri@le.infn.it; Mancini, Stefano [Dipartimento di Fisica, Universita di Camerino, I-62032 Camerino (Italy)]. E-mail: stefano.mancini@unicam.it

    2007-03-12

    We study the security of the information transmission between two honest parties realized through a lossy bosonic memory channel when losses are captured by a dishonest party. We then show that entangled inputs can enhance the private information of such a channel, which however does never overcome that of unentangled inputs in absence of memory.

  7. Privacy of a lossy bosonic memory channel

    International Nuclear Information System (INIS)

    Ruggeri, Giovanna; Mancini, Stefano

    2007-01-01

    We study the security of the information transmission between two honest parties realized through a lossy bosonic memory channel when losses are captured by a dishonest party. We then show that entangled inputs can enhance the private information of such a channel, which however does never overcome that of unentangled inputs in absence of memory

  8. Generation and Context Memory

    Science.gov (United States)

    Mulligan, Neil W.; Lozito, Jeffrey P.; Rosner, Zachary A.

    2006-01-01

    Generation enhances memory for occurrence but may not enhance other aspects of memory. The present study further delineates the negative generation effect in context memory reported in N. W. Mulligan (2004). First, the negative generation effect occurred for perceptual attributes of the target item (its color and font) but not for extratarget…

  9. Critical period of memory enhancement during taste avoidance conditioning in Lymnaea stagnalis.

    Science.gov (United States)

    Takahashi, Tomoyo; Takigami, Satoshi; Sunada, Hiroshi; Lukowiak, Ken; Sakakibara, Manabu

    2013-01-01

    The present study investigated the optimal training procedure leading to long-lasting taste avoidance behavior in Lymnaea. A training procedure comprising 5 repeated pairings of a conditional stimulus (CS, sucrose), with an unconditional stimulus (US, a tactile stimulation to the animal's head), over a 4-day period resulted in an enhanced memory formation than 10 CS-US repeated pairings over a 2-day period or 20 CS-US repeated pairings on a single day. Backward conditioning (US-CS) pairings did not result in conditioning. Thus, this taste avoidance conditioning was CS-US pairing specific. Food avoidance behavior was not observed following training, however, if snails were immediately subjected to a cold-block (4°C for 10 min). It was critical that the cold-block be applied within 10 min to block long-term memory (LTM) formation. Further, exposure to the cold-block 180 min after training also blocked both STM and LTM formation. The effects of the cold-block on subsequent learning and memory formation were also examined. We found no long lasting effects of the cold-block on subsequent memory formation. If protein kinase C was activated before the conditioning paradigm, snails could still acquire STM despite exposure to the cold-block.

  10. Critical period of memory enhancement during taste avoidance conditioning in Lymnaea stagnalis.

    Directory of Open Access Journals (Sweden)

    Tomoyo Takahashi

    Full Text Available The present study investigated the optimal training procedure leading to long-lasting taste avoidance behavior in Lymnaea. A training procedure comprising 5 repeated pairings of a conditional stimulus (CS, sucrose, with an unconditional stimulus (US, a tactile stimulation to the animal's head, over a 4-day period resulted in an enhanced memory formation than 10 CS-US repeated pairings over a 2-day period or 20 CS-US repeated pairings on a single day. Backward conditioning (US-CS pairings did not result in conditioning. Thus, this taste avoidance conditioning was CS-US pairing specific. Food avoidance behavior was not observed following training, however, if snails were immediately subjected to a cold-block (4°C for 10 min. It was critical that the cold-block be applied within 10 min to block long-term memory (LTM formation. Further, exposure to the cold-block 180 min after training also blocked both STM and LTM formation. The effects of the cold-block on subsequent learning and memory formation were also examined. We found no long lasting effects of the cold-block on subsequent memory formation. If protein kinase C was activated before the conditioning paradigm, snails could still acquire STM despite exposure to the cold-block.

  11. Features of an Error Correction Memory to Enhance Technical Texts Authoring in LELIE

    Directory of Open Access Journals (Sweden)

    Patrick SAINT-DIZIER

    2015-12-01

    Full Text Available In this paper, we investigate the notion of error correction memory applied to technical texts. The main purpose is to introduce flexibility and context sensitivity in the detection and the correction of errors related to Constrained Natural Language (CNL principles. This is realized by enhancing error detection paired with relatively generic correction patterns and contextual correction recommendations. Patterns are induced from previous corrections made by technical writers for a given type of text. The impact of such an error correction memory is also investigated from the point of view of the technical writer's cognitive activity. The notion of error correction memory is developed within the framework of the LELIE project an experiment is carried out on the case of fuzzy lexical items and negation, which are both major problems in technical writing. Language processing and knowledge representation aspects are developed together with evaluation directions.

  12. Enhancing long-term memory with stimulation tunes visual attention in one trial

    OpenAIRE

    Reinhart, Robert M. G.; Woodman, Geoffrey F.

    2014-01-01

    Theories of attention propose that we rely on working memory to control attention by maintaining target presentations in this active store as our visual systems are used to search for certain objects. Here, we show that the tuning of perceptual attention can be sharply accelerated by noninvasive brain stimulation. Our electrophysiological measurements showed that these improvements in attentional tuning were preceded by changes in event-related potentials thought to index long-term memory, bu...

  13. On the susceptibility of adaptive memory to false memory illusions.

    Science.gov (United States)

    Howe, Mark L; Derbish, Mary H

    2010-05-01

    Previous research has shown that survival-related processing of word lists enhances retention for that material. However, the claim that survival-related memories are more accurate has only been examined when true recall and recognition of neutral material has been measured. In the current experiments, we examined the adaptive memory superiority effect for different types of processing and material, measuring accuracy more directly by comparing true and false recollection rates. Survival-related information and processing was examined using word lists containing backward associates of neutral, negative, and survival-related critical lures and type of processing (pleasantness, moving, survival) was varied using an incidental memory paradigm. Across four experiments, results showed that survival-related words were more susceptible than negative and neutral words to the false memory illusion and that processing information in terms of its relevance to survival independently increased this susceptibility to the false memory illusion. Overall, although survival-related processing and survival-related information resulted in poorer, not more accurate, memory, such inaccuracies may have adaptive significance. These findings are discussed in the context of false memory research and recent theories concerning the importance of survival processing and the nature of adaptive memory. Copyright 2009 Elsevier B.V. All rights reserved.

  14. Stress enhances reconsolidation of declarative memory

    NARCIS (Netherlands)

    Bos, M.G.N.; Schuijer, J.; Lodestijn, F.; Beckers, T.; Kindt, M.

    2014-01-01

    Retrieval of negative emotional memories is often accompanied by the experience of stress. Upon retrieval, a memory trace can temporarily return into a labile state, where it is vulnerable to change. An unresolved question is whether post-retrieval stress may affect the strength of declarative

  15. Short-term memory to long-term memory transition in a nanoscale memristor.

    Science.gov (United States)

    Chang, Ting; Jo, Sung-Hyun; Lu, Wei

    2011-09-27

    "Memory" is an essential building block in learning and decision-making in biological systems. Unlike modern semiconductor memory devices, needless to say, human memory is by no means eternal. Yet, forgetfulness is not always a disadvantage since it releases memory storage for more important or more frequently accessed pieces of information and is thought to be necessary for individuals to adapt to new environments. Eventually, only memories that are of significance are transformed from short-term memory into long-term memory through repeated stimulation. In this study, we show experimentally that the retention loss in a nanoscale memristor device bears striking resemblance to memory loss in biological systems. By stimulating the memristor with repeated voltage pulses, we observe an effect analogous to memory transition in biological systems with much improved retention time accompanied by additional structural changes in the memristor. We verify that not only the shape or the total number of stimuli is influential, but also the time interval between stimulation pulses (i.e., the stimulation rate) plays a crucial role in determining the effectiveness of the transition. The memory enhancement and transition of the memristor device was explained from the microscopic picture of impurity redistribution and can be qualitatively described by the same equations governing biological memories. © 2011 American Chemical Society

  16. Auditory enhancement of visual memory encoding is driven by emotional content of the auditory material and mediated by superior frontal cortex.

    Science.gov (United States)

    Proverbio, A M; De Benedetto, F

    2018-02-01

    The aim of the present study was to investigate how auditory background interacts with learning and memory. Both facilitatory (e.g., "Mozart effect") and interfering effects of background have been reported, depending on the type of auditory stimulation and of concurrent cognitive tasks. Here we recorded event related potentials (ERPs) during face encoding followed by an old/new memory test to investigate the effect of listening to classical music (Čajkovskij, dramatic), environmental sounds (rain) or silence on learning. Participants were 15 healthy non-musician university students. Almost 400 (previously unknown) faces of women and men of various age were presented. Listening to music during study led to a better encoding of faces as indexed by an increased Anterior Negativity. The FN400 response recorded during the memory test showed a gradient in its amplitude reflecting face familiarity. FN400 was larger to new than old faces, and to faces studied during rain sound listening and silence than music listening. The results indicate that listening to music enhances memory recollection of faces by merging with visual information. A swLORETA analysis showed the main involvement of Superior Temporal Gyrus (STG) and medial frontal gyrus in the integration of audio-visual information. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Joint effects of emotion and color on memory.

    Science.gov (United States)

    Kuhbandner, Christof; Pekrun, Reinhard

    2013-06-01

    Numerous studies have shown that memory is enhanced for emotionally negative and positive information relative to neutral information. We examined whether emotion-induced memory enhancement is influenced by low-level perceptual attributes such as color. Because in everyday life red is often used as a warning signal, whereas green signals security, we hypothesized that red might enhance memory for negative information and green memory for positive information. To capture the signaling function of colors, we measured memory for words standing out from the context by color, and manipulated the color and emotional significance of the outstanding words. Making words outstanding by color strongly enhanced memory, replicating the well-known von Restorff effect. Furthermore, memory for colored words was further increased by emotional significance, replicating the memory-enhancing effect of emotion. Most intriguingly, the effects of emotion on memory additionally depended on color type. Red strongly increased memory for negative words, whereas green strongly increased memory for positive words. These findings provide the first evidence that emotion-induced memory enhancement is influenced by color and demonstrate that different colors can have different functions in human memory.

  18. Neural Correlates of Opposing Effects of Emotional Distraction on Working Memory and Episodic Memory: An Event Related fMRI Investigation

    Directory of Open Access Journals (Sweden)

    Florin eDolcos

    2013-06-01

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

  19. Happiness increases verbal and spatial working memory capacity where sadness does not: Emotion, working memory and executive control.

    Science.gov (United States)

    Storbeck, Justin; Maswood, Raeya

    2016-08-01

    The effects of emotion on working memory and executive control are often studied in isolation. Positive mood enhances verbal and impairs spatial working memory, whereas negative mood enhances spatial and impairs verbal working memory. Moreover, positive mood enhances executive control, whereas negative mood has little influence. We examined how emotion influences verbal and spatial working memory capacity, which requires executive control to coordinate between holding information in working memory and completing a secondary task. We predicted that positive mood would improve both verbal and spatial working memory capacity because of its influence on executive control. Positive, negative and neutral moods were induced followed by completing a verbal (Experiment 1) or spatial (Experiment 2) working memory operation span task to assess working memory capacity. Positive mood enhanced working memory capacity irrespective of the working memory domain, whereas negative mood had no influence on performance. Thus, positive mood was more successful holding information in working memory while processing task-irrelevant information, suggesting that the influence mood has on executive control supersedes the independent effects mood has on domain-specific working memory.

  20. No Evidence for Improved Associative Memory Performance Following Process-Based Associative Memory Training in Older Adults.

    Science.gov (United States)

    Bellander, Martin; Eschen, Anne; Lövdén, Martin; Martin, Mike; Bäckman, Lars; Brehmer, Yvonne

    2016-01-01

    Studies attempting to improve episodic memory performance with strategy instructions and training have had limited success in older adults: their training gains are limited in comparison to those of younger adults and do not generalize to untrained tasks and contexts. This limited success has been partly attributed to age-related impairments in associative binding of information into coherent episodes. We therefore investigated potential training and transfer effects of process-based associative memory training (i.e., repeated practice). Thirty-nine older adults ( M age = 68.8) underwent 6 weeks of either adaptive associative memory training or item recognition training. Both groups improved performance in item memory, spatial memory (object-context binding) and reasoning. A disproportionate effect of associative memory training was only observed for item memory, whereas no training-related performance changes were observed for associative memory. Self-reported strategies showed no signs of spontaneous development of memory-enhancing associative memory strategies. Hence, the results do not support the hypothesis that process-based associative memory training leads to higher associative memory performance in older adults.

  1. Strategic value-directed learning and memory in Alzheimer's disease and behavioural-variant frontotemporal dementia.

    Science.gov (United States)

    Wong, Stephanie; Irish, Muireann; Savage, Greg; Hodges, John R; Piguet, Olivier; Hornberger, Michael

    2018-02-12

    In healthy adults, the ability to prioritize learning of highly valued information is supported by executive functions and enhances subsequent memory retrieval for this information. In Alzheimer's disease (AD) and behavioural-variant frontotemporal dementia (bvFTD), marked deficits are evident in learning and memory, presenting in the context of executive dysfunction. It is unclear whether these patients show a typical memory bias for higher valued stimuli. We administered a value-directed word-list learning task to AD (n = 10) and bvFTD (n = 21) patients and age-matched healthy controls (n = 22). Each word was assigned a low, medium or high point value, and participants were instructed to maximize the number of points earned across three learning trials. Participants' memory for the words was assessed on a delayed recall trial, followed by a recognition test for the words and corresponding point values. Relative to controls, both patient groups showed poorer overall learning, delayed recall and recognition. Despite these impairments, patients with AD preferentially recalled high-value words on learning trials and showed significant value-directed enhancement of recognition memory for the words and points. Conversely, bvFTD patients did not prioritize recall of high-value words during learning trials, and this reduced selectivity was related to inhibitory dysfunction. Nonetheless, bvFTD patients showed value-directed enhancement of recognition memory for the point values, suggesting a mismatch between memory of high-value information and the ability to apply this in a motivationally salient context. Our findings demonstrate that value-directed enhancement of memory may persist to some degree in patients with dementia, despite pronounced deficits in learning and memory. © 2018 The British Psychological Society.

  2. What You See Is What You Remember: Visual Chunking by Temporal Integration Enhances Working Memory.

    Science.gov (United States)

    Akyürek, Elkan G; Kappelmann, Nils; Volkert, Marc; van Rijn, Hedderik

    2017-12-01

    Human memory benefits from information clustering, which can be accomplished by chunking. Chunking typically relies on expertise and strategy, and it is unknown whether perceptual clustering over time, through temporal integration, can also enhance working memory. The current study examined the attentional and working memory costs of temporal integration of successive target stimulus pairs embedded in rapid serial visual presentation. ERPs were measured as a function of behavioral reports: One target, two separate targets, or two targets reported as a single integrated target. N2pc amplitude, reflecting attentional processing, depended on the actual number of successive targets. The memory-related CDA and P3 components instead depended on the perceived number of targets irrespective of their actual succession. The report of two separate targets was associated with elevated amplitude, whereas integrated as well as actual single targets exhibited lower amplitude. Temporal integration thus provided an efficient means of processing sensory input, offloading working memory so that the features of two targets were consolidated and maintained at a cost similar to that of a single target.

  3. Task activation and functional connectivity show concordant memory laterality in temporal lobe epilepsy.

    Science.gov (United States)

    Sideman, Noah; Chaitanya, Ganne; He, Xiaosong; Doucet, Gaelle; Kim, Na Young; Sperling, Michael R; Sharan, Ashwini D; Tracy, Joseph I

    2018-04-01

    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

  4. Memory for details with self-referencing.

    Science.gov (United States)

    Serbun, Sarah J; Shih, Joanne Y; Gutchess, Angela H

    2011-11-01

    Self-referencing benefits item memory, but little is known about the ways in which referencing the self affects memory for details. Experiment 1 assessed whether the effects of self-referencing operate only at the item, or general, level or whether they also enhance memory for specific visual details of objects. Participants incidentally encoded objects by making judgements in reference to the self, a close other (one's mother), or a familiar other (Bill Clinton). Results indicate that referencing the self or a close other enhances both specific and general memory. Experiments 2 and 3 assessed verbal memory for source in a task that relied on distinguishing between different mental operations (internal sources). The results indicate that self-referencing disproportionately enhances source memory, relative to conditions referencing other people, semantic, or perceptual information. We conclude that self-referencing not only enhances specific memory for both visual and verbal information, but can also disproportionately improve memory for specific internal source details.

  5. Memory-enhancing corticosterone treatment increases amygdala norepinephrine and Arc protein expression in hippocampal synaptic fractions

    NARCIS (Netherlands)

    McReynolds, Jayme R.; Donowho, Kyle; Abdi, Amin; McGaugh, James L.; Roozendaal, Benno; McIntyre, Christa K.

    Considerable evidence indicates that glucocorticoid hormones enhance the consolidation of memory for emotionally arousing events through interactions with the noradrenergic system of the basolateral complex of the amygdala (BLA). We previously reported that intra-BLA administration of a

  6. Battery powered thought: enhancement of attention, learning, and memory in healthy adults using transcranial direct current stimulation.

    Science.gov (United States)

    Coffman, Brian A; Clark, Vincent P; Parasuraman, Raja

    2014-01-15

    This article reviews studies demonstrating enhancement with transcranial direct current stimulation (tDCS) of attention, learning, and memory processes in healthy adults. Given that these are fundamental cognitive functions, they may also mediate stimulation effects on other higher-order processes such as decision-making and problem solving. Although tDCS research is still young, there have been a variety of methods used and cognitive processes tested. While these different methods have resulted in seemingly contradictory results among studies, many consistent and noteworthy effects of tDCS on attention, learning, and memory have been reported. The literature suggests that although tDCS as typically applied may not be as useful for localization of function in the brain as some other methods of brain stimulation, tDCS may be particularly well-suited for practical applications involving the enhancement of attention, learning, and memory, in both healthy subjects and in clinical populations. © 2013 Elsevier Inc. All rights reserved.

  7. Nobiletin improves emotional and novelty recognition memory but not spatial referential memory.

    Science.gov (United States)

    Kang, Jiyun; Shin, Jung-Won; Kim, Yoo-Rim; Swanberg, Kelley M; Kim, Yooseung; Bae, Jae Ryong; Kim, Young Ki; Lee, Jinwon; Kim, Soo-Yeon; Sohn, Nak-Won; Maeng, Sungho

    2017-01-01

    How to maintain and enhance cognitive functions for both aged and young populations is a highly interesting subject. But candidate memory-enhancing reagents are tested almost exclusively on lesioned or aged animals. Also, there is insufficient information on the type of memory these reagents can improve. Working memory, located in the prefrontal cortex, manages short-term sensory information, but, by gaining significant relevance, this information is converted to long-term memory by hippocampal formation and/or amygdala, followed by tagging with space-time or emotional cues, respectively. Nobiletin is a product of citrus peel known for cognitive-enhancing effects in various pharmacological and neurodegenerative disease models, yet, it is not well studied in non-lesioned animals and the type of memory that nobiletin can improve remains unclear. In this study, 8-week-old male mice were tested using behavioral measurements for working, spatial referential, emotional and visual recognition memory after daily administration of nobiletin. While nobiletin did not induce any change of spontaneous activity in the open field test, freezing by fear conditioning and novel object recognition increased. However, the effectiveness of spatial navigation in the Y-maze and Morris water maze was not improved. These results mean that nobiletin can specifically improve memories of emotionally salient information associated with fear and novelty, but not of spatial information without emotional saliency. Accordingly, the use of nobiletin on normal subjects as a memory enhancer would be more effective on emotional types but may have limited value for the improvement of episodic memories.

  8. Amyloid β Enhances Typical Rodent Behavior While It Impairs Contextual Memory Consolidation.

    Science.gov (United States)

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

    2015-01-01

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

  9. Enhancement of long-term spatial memory in adult rats by the noncompetitive NMDA receptor antagonists, memantine and neramexane.

    Science.gov (United States)

    Zoladz, Phillip R; Campbell, Adam M; Park, Collin R; Schaefer, Daniela; Danysz, Wojciech; Diamond, David M

    2006-10-01

    Memantine and neramexane are noncompetitive NMDA receptor antagonists which have been investigated for their promising effects in aiding memory in people with dementia. Memantine is approved for the treatment of Alzheimer's disease, and neramexane is currently under development for this indication. Therefore, the present study provided a comparative assessment of the effects of equimolar doses of memantine and neramexane on spatial (hippocampus-dependent) memory. Adult male rats were given only 3 training trials to learn the location of a hidden platform in a water maze. In control (vehicle-injected) rats, this minimal amount of training produced intact short-term (15 min), but poor long-term (24 h), memory. Pre-training administration of memantine or neramexane produced a dose-dependent enhancement of long-term memory. Pharmacokinetic experiments with equimolar doses of both agents indicated that lower plasma levels of neramexane were more effective than memantine at enhancing memory. The effective doses of both agents in the current study produced plasma levels (and extrapolated brain CSF levels) within a range of activity at NMDA receptors and plasma levels seen in patients with Alzheimer's disease. These findings provide support for the use of neramexane as a pharmacological intervention in the treatment of dementia.

  10. Effects of the histamine H₃ receptor antagonist ABT-239 on cognition and nicotine-induced memory enhancement in mice.

    Science.gov (United States)

    Kruk, Marta; Miszkiel, Joanna; McCreary, Andrew C; Przegaliński, Edmund; Filip, Małgorzata; Biała, Grażyna

    2012-01-01

    The strong correlation between central histaminergic and cholinergic pathways on cognitive processes has been reported extensively. However, the role of histamine H(3) receptor mechanisms interacting with nicotinic mechanisms has not previously been extensively investigated. The current study was conducted to determine the interactions of nicotinic and histamine H(3) receptor systems with regard to learning and memory function using a modified elevated plus-maze test in mice. In this test, the latency for mice to move from the open arm to the enclosed arm (i.e., transfer latency) was used as an index of memory. We tested whether ABT-239 (4-(2-{2-[(2R)-2-methylpyrrolidinyl]ethyl}-benzofuran-5-yl), an H(3) receptor antagonist/inverse agonist, had influence on two different stages of memory, i.e., memory acquisition and consolidation (administered prior to or immediately after the first trial, respectively) and whether ABT-239 influenced nicotine-induced memory enhancement. Our results revealed that the acute administration of nicotine (0.035 and 0.175 mg/kg), but not of ABT-239 (0.1-3 mg/kg) reduced transfer latency in the acquisition and consolidation phases. In combination studies, concomitant administration of either ABT-239 (1 and 3 mg/kg) and nicotine (0.035 mg/kg), or ABT-239 (0.1 mg/kg) and nicotine (0.0175 mg/kg) further increased nicotine-induced improvement in both memory acquisition and consolidation. The present data confirm an important role for H(3) receptors in regulating nicotine-induced mnemonic effects since inhibition of H(3) receptors augmented nicotine-induced memory enhancement in mice.

  11. Entanglement and optimal strings of qubits for memory channels

    International Nuclear Information System (INIS)

    Karimipour, V.; Memarzadeh, L.

    2006-01-01

    We investigate the problem of enhancement of mutual information by encoding classical data into entangled input states of arbitrary length and show that while there is a threshold memory or correlation parameter beyond which entangled states outperform the separable states, resulting in a higher mutual information, this memory threshold increases toward unity as the length of the string increases. These observations imply that encoding classical data into entangled states may not enhance the classical capacity of quantum channels

  12. High Stakes Trigger the Use of Multiple Memories to Enhance the Control of Attention

    Science.gov (United States)

    Reinhart, Robert M.G.; Woodman, Geoffrey F.

    2014-01-01

    We can more precisely tune attention to highly rewarding objects than other objects in our environment, but how our brains do this is unknown. After a few trials of searching for the same object, subjects' electrical brain activity indicated that they handed off the memory representations used to control attention from working memory to long-term memory. However, when a large reward was possible, the neural signature of working memory returned as subjects recruited working memory to supplement the cognitive control afforded by the representations accumulated in long-term memory. The amplitude of this neural signature of working memory predicted the magnitude of the subsequent behavioral reward-based attention effects across tasks and individuals, showing the ubiquity of this cognitive reaction to high-stakes situations. PMID:23448876

  13. Drinkers’ memory bias for alcohol picture cues in explicit and implicit memory tasks

    Science.gov (United States)

    Nguyen-Louie, Tam T.; Buckman, Jennifer F.; Ray, Suchismita

    2016-01-01

    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

  14. Drinkers' memory bias for alcohol picture cues in explicit and implicit memory tasks.

    Science.gov (United States)

    Nguyen-Louie, Tam T; Buckman, Jennifer F; Ray, Suchismita; Bates, Marsha E

    2016-03-01

    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.

  15. Memory Performance for Everyday Motivational and Neutral Objects Is Dissociable from Attention

    Directory of Open Access Journals (Sweden)

    Judith Schomaker

    2017-06-01

    Full Text Available Episodic memory is typically better for items coupled with monetary reward or punishment during encoding. It is yet unclear whether memory is also enhanced for everyday objects with appetitive or aversive values learned through a lifetime of experience, and to what extent episodic memory enhancement for motivational and neutral items is attributable to attention. In a first experiment, we investigated attention to everyday motivational objects using eye-tracking during free-viewing and subsequently tested episodic memory using a remember/know procedure. Attention was directed more to aversive stimuli, as evidenced by longer viewing durations, whereas recollection was higher for both appetitive and aversive objects. In the second experiment, we manipulated the visual contrast of neutral objects through changes of contrast to further dissociate attention and memory encoding. While objects presented with high visual contrast were looked at longer, recollection was best for objects presented in unmodified, medium contrast. Generalized logistic mixed models on recollection performance showed that attention as measured by eye movements did not enhance subsequent memory, while motivational value (Experiment 1 and visual contrast (Experiment 2 had quadratic effects in opposite directions. Our findings suggest that an enhancement of incidental memory encoding for appetitive items can occur without an increase in attention and, vice versa, that enhanced attention towards salient neutral objects is not necessarily associated with memory improvement. Together, our results provide evidence for a double dissociation of attention and memory effects under certain conditions.

  16. Memory Performance for Everyday Motivational and Neutral Objects Is Dissociable from Attention

    Science.gov (United States)

    Schomaker, Judith; Wittmann, Bianca C.

    2017-01-01

    Episodic memory is typically better for items coupled with monetary reward or punishment during encoding. It is yet unclear whether memory is also enhanced for everyday objects with appetitive or aversive values learned through a lifetime of experience, and to what extent episodic memory enhancement for motivational and neutral items is attributable to attention. In a first experiment, we investigated attention to everyday motivational objects using eye-tracking during free-viewing and subsequently tested episodic memory using a remember/know procedure. Attention was directed more to aversive stimuli, as evidenced by longer viewing durations, whereas recollection was higher for both appetitive and aversive objects. In the second experiment, we manipulated the visual contrast of neutral objects through changes of contrast to further dissociate attention and memory encoding. While objects presented with high visual contrast were looked at longer, recollection was best for objects presented in unmodified, medium contrast. Generalized logistic mixed models on recollection performance showed that attention as measured by eye movements did not enhance subsequent memory, while motivational value (Experiment 1) and visual contrast (Experiment 2) had quadratic effects in opposite directions. Our findings suggest that an enhancement of incidental memory encoding for appetitive items can occur without an increase in attention and, vice versa, that enhanced attention towards salient neutral objects is not necessarily associated with memory improvement. Together, our results provide evidence for a double dissociation of attention and memory effects under certain conditions. PMID:28694774

  17. Memory Performance for Everyday Motivational and Neutral Objects Is Dissociable from Attention.

    Science.gov (United States)

    Schomaker, Judith; Wittmann, Bianca C

    2017-01-01

    Episodic memory is typically better for items coupled with monetary reward or punishment during encoding. It is yet unclear whether memory is also enhanced for everyday objects with appetitive or aversive values learned through a lifetime of experience, and to what extent episodic memory enhancement for motivational and neutral items is attributable to attention. In a first experiment, we investigated attention to everyday motivational objects using eye-tracking during free-viewing and subsequently tested episodic memory using a remember/know procedure. Attention was directed more to aversive stimuli, as evidenced by longer viewing durations, whereas recollection was higher for both appetitive and aversive objects. In the second experiment, we manipulated the visual contrast of neutral objects through changes of contrast to further dissociate attention and memory encoding. While objects presented with high visual contrast were looked at longer, recollection was best for objects presented in unmodified, medium contrast. Generalized logistic mixed models on recollection performance showed that attention as measured by eye movements did not enhance subsequent memory, while motivational value (Experiment 1) and visual contrast (Experiment 2) had quadratic effects in opposite directions. Our findings suggest that an enhancement of incidental memory encoding for appetitive items can occur without an increase in attention and, vice versa, that enhanced attention towards salient neutral objects is not necessarily associated with memory improvement. Together, our results provide evidence for a double dissociation of attention and memory effects under certain conditions.

  18. A short CD3/CD28 costimulation combined with IL-21 enhance the generation of human memory stem T cells for adoptive immunotherapy.

    Science.gov (United States)

    Alvarez-Fernández, C; Escribà-Garcia, L; Vidal, S; Sierra, J; Briones, J

    2016-07-19

    Immunotherapy based on the adoptive transfer of gene modified T cells is an emerging approach for the induction of tumor-specific immune responses. Memory stem T cells, due to their enhanced antitumor and self-renewal capacity, have become potential candidate for adoptive T cell therapy of cancer. Methods to generate memory stem T cells ex vivo rely on CD3/CD28 costimulation and the use of cytokines such as IL-7 and IL-15 during the entire culture period. However, a strong costimulation may induce differentiation of memory stem T cells to effector memory T cells. Here we show that manipulation of the length of the costimulation and addition of IL-21 enhance the ex vivo expansion of memory stem T cells. Purified naïve T cells from healthy donors were cultured in the presence of anti-CD3/CD28 coated beads, IL-7, IL-15 and/or IL-21 (25 ng/ml). T cells phenotype from the different memory and effector subpopulations were analyzed by multiparametric flow cytometry. A short anti-CD3/CD28 costimulation of naïve T cells, combined with IL-7 and IL-15 significantly increased the frequencies of CD4(+) and CD8(+) memory stem T cells ex vivo, compared to a prolonged costimulation (34.6 ± 4.4 % vs 15.6 ± 4.24 % in CD4(+); p = 0.008, and 20.5 ± 4.00 % vs 7.7 ± 2.53 % in CD8(+); p = 0.02). Moreover, the addition of IL-21 to this condition further enhanced the enrichment and expansion of CD4(+) and CD8(+) memory stem T cells with an increase in the absolute numbers (0.7 × 10(6) ± 0.1 vs 0.26 × 10(6) ± 0.1 cells for CD4(+); p = 0.002 and 1.1 × 10(6) ± 0.1 vs 0.27 × 10(6) ± 0.1 cells for CD8(+); p = 0.0002; short + IL-21 vs long). These new in vitro conditions increase the frequencies and expansion of memory stem T cells and may have relevant clinical implications for the generation of this memory T cell subset for adoptive cell therapy of patients with cancer.

  19. Memory-enhancing effect of a supercritical carbon dioxide fluid extract of the needles of Abies koreana on scopolamine-induced amnesia in mice.

    Science.gov (United States)

    Kim, Kanghyun; Bu, Youngmin; Jeong, Seungil; Lim, Jongpil; Kwon, Youngan; Cha, Dong Seok; Kim, Jinmo; Jeon, Sora; Eun, Jaesoon; Jeon, Hoon

    2006-08-01

    Abies koreana Wilson (A. koreana) is a shrub or broadly pyramidal evergreen tree endemic in the mountainous regions of South Korea. We obtained the essential oil (EO) from alpine needle leaves of A. koreana by the supercritical fluid extraction (SFE) method. EO was analyzed by gas chromatography-mass spectrometry (GC-MS), and 68 compounds were identified constituting 95.66% of the oil. The major components were elemol (11.17%), terpinen-4-ol (9.77%), sabinene (8.86%), 10(15)-cadien-4-ol (7.16%), alpha-terpineol (6.13%), alpha-pinene (6.07%) and gamma-terpinene (4.71%). To investigate the memory-enhancing effects, we conducted a passive avoidance test using a scopolamine (1 mg/kg, ip)-induced amnesia mouse model. A peritoneal injection of EO from A. koreana (100 mg/kg) showed a memory enhancing effect of 72.7% compared with the control. These results suggest that EO of A. koreana may be a useful therapeutic agent against such amnesia-inducing diseases as Alzheimer and vascular dementia.

  20. Lateralized odor preference training in rat pups reveals an enhanced network response in anterior piriform cortex to olfactory input that parallels extended memory.

    Science.gov (United States)

    Fontaine, Christine J; Harley, Carolyn W; Yuan, Qi

    2013-09-18

    The present study examines synaptic plasticity in the anterior piriform cortex (aPC) using ex vivo slices from rat pups given lateralized odor preference training. In the early odor preference learning model, a brief 10 min training session yields 24 h memory, while four daily sessions yield 48 h memory. Odor preference memory can be lateralized through naris occlusion as the anterior commissure is not yet functional. AMPA receptor-mediated postsynaptic responses in the aPC to lateral olfactory tract input, shown to be enhanced at 24 h, are no longer enhanced 48 h after a single training session. Following four spaced lateralized trials, the AMPA receptor-mediated fEPSP is enhanced in the trained aPC at 48 h. Calcium imaging of aPC pyramidal cells within 48 h revealed decreased firing thresholds in the pyramidal cell network. Thus multiday odor preference training induced increased odor input responsiveness in previously weakly activated aPC cells. These results support the hypothesis that increased synaptic strength in olfactory input networks mediates odor preference memory. The increase in aPC network activation parallels behavioral memory.

  1. Self-defining memories during exposure to music in Alzheimer's disease.

    Science.gov (United States)

    El Haj, Mohamad; Antoine, Pascal; Nandrino, Jean Louis; Gély-Nargeot, Marie-Christine; Raffard, Stéphane

    2015-10-01

    Research suggests that exposure to music may enhance autobiographical recall in Alzheimer's Disease (AD) patients. This study investigated whether exposure to music could enhance the production of self-defining memories, that is, memories that contribute to self-discovery, self-understanding, and identity in AD patients. Twenty-two mild-stage AD patients and 24 healthy controls were asked to produce autobiographical memories in silence, while listening to researcher-chosen music, and to their own-chosen music. AD patients showed better autobiographical recall when listening to their own-chosen music than to researcher-chosen music or than in silence. More precisely, they produced more self-defining memories during exposure to their own-chosen music than to researcher-chosen music or during silence. Additionally, AD patients produced more self-defining memories than autobiographical episodes or personal-semantics during exposure to their own-chosen music. This pattern contrasted with the poor production of self-defining memories during silence or during exposure to researcher-chosen music. Healthy controls did not seem to enjoy the same autobiographical benefits nor the same self-defining memory enhancement in the self-chosen music condition. Poor production of self-defining memories, as observed in AD, may somehow be alleviated by exposure to self-chosen music.

  2. Better than sleep: theta neurofeedback training accelerates memory consolidation.

    Science.gov (United States)

    Reiner, Miriam; Rozengurt, Roman; Barnea, Anat

    2014-01-01

    Consistent empirical results showed that both night and day sleep enhanced memory consolidation. In this study we explore processes of consolidation of memory during awake hours. Since theta oscillations have been shown to play a central role in exchange of information, we hypothesized that elevated theta during awake hours will enhance memory consolidation. We used a neurofeedback protocol, to enhance the relative power of theta or beta oscillations. Participants trained on a tapping task, were divided into three groups: neurofeedback theta; neurofeedback beta; control. We found a significant improvement in performance in the theta group, relative to the beta and control groups, immediately after neurofeedback. Performance was further improved after night sleep in all groups, with a significant advantage favoring the theta group. Theta power during training was correlated with the level of improvement, indicating a clear relationship between memory consolidation, and theta neurofeedback. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Acetylation-mediated suppression of transcription-independent memory: bidirectional modulation of memory by acetylation.

    Directory of Open Access Journals (Sweden)

    Katja Merschbaecher

    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.

  4. The effect of caffeine on working memory load-related brain activation in middle-aged males

    NARCIS (Netherlands)

    Klaassen, E.B.; de Groot, R.H.M.; Evers, E.A.T.; Snel, J.; Veerman, E.C.I.; Ligtenberg, A.J.M.; Jolles, J.; Veltman, D.J.

    2013-01-01

    Caffeine is commonly consumed in an effort to enhance cognitive performance. However, little is known about the usefulness of caffeine with regard to memory enhancement, with previous studies showing inconsistent effects on memory performance. We aimed to determine the effect of caffeine on working

  5. Enhanced memory performance thanks to neural network assortativity

    International Nuclear Information System (INIS)

    Franciscis, S. de; Johnson, S.; Torres, J. J.

    2011-01-01

    The behaviour of many complex dynamical systems has been found to depend crucially on the structure of the underlying networks of interactions. An intriguing feature of empirical networks is their assortativity--i.e., the extent to which the degrees of neighbouring nodes are correlated. However, until very recently it was difficult to take this property into account analytically, most work being exclusively numerical. We get round this problem by considering ensembles of equally correlated graphs and apply this novel technique to the case of attractor neural networks. Assortativity turns out to be a key feature for memory performance in these systems - so much so that for sufficiently correlated topologies the critical temperature diverges. We predict that artificial and biological neural systems could significantly enhance their robustness to noise by developing positive correlations.

  6. Preserved memory-based orienting of attention with impaired explicit memory in healthy ageing.

    Science.gov (United States)

    Salvato, Gerardo; Patai, Eva Z; Nobre, Anna C

    2016-01-01

    It is increasingly recognised that spatial contextual long-term memory (LTM) prepares neural activity for guiding visuo-spatial attention in a proactive manner. In the current study, we investigated whether the decline in explicit memory observed in healthy ageing would compromise this mechanism. We compared the behavioural performance of younger and older participants on learning new contextual memories, on orienting visual attention based on these learnt contextual associations, and on explicit recall of contextual memories. We found a striking dissociation between older versus younger participants in the relationship between the ability to retrieve contextual memories versus the ability to use these to guide attention to enhance performance on a target-detection task. Older participants showed significant deficits in the explicit retrieval task, but their behavioural benefits from memory-based orienting of attention were equivalent to those in young participants. Furthermore, memory-based orienting correlated significantly with explicit contextual LTM in younger adults but not in older adults. These results suggest that explicit memory deficits in ageing might not compromise initial perception and encoding of events. Importantly, the results also shed light on the mechanisms of memory-guided attention, suggesting that explicit contextual memories are not necessary. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Mating and Memory

    Directory of Open Access Journals (Sweden)

    Michael D. Baker

    2015-12-01

    Full Text Available The literature on sexual selection and the social brain hypothesis suggest that human cognition and communication evolved, in part, for the purpose of displaying desirable cognitive abilities to potential mates. An evolutionary approach to social cognition implies that proximate mating motives may lead people to display desirable mental traits. In signaling such traits, one can increase the likelihood of attracting a potential mate. Two experiments demonstrated that exposure to mating cues—highly attractive opposite-sex faces—led people to display enhancements in declarative memory—a process underlying a variety of abilities such as resource acquisition, intelligence, and creativity. Experiment 1 showed that men (but not women displayed enhanced memory for details of a story that was presented during exposure to highly attractive opposite-sex faces. Experiment 2 demonstrated that heightened displays of declarative memory reflect an enhancement in retrieval rather than in encoding. Findings contribute to the literatures on human mating and cognitive performance and provide novel insight into links between social processes and basic cognition.

  8. Novel Organic Phototransistor-Based Nonvolatile Memory Integrated with UV-Sensing/Green-Emissive Aggregation Enhanced Emission (AEE)-Active Aromatic Polyamide Electret Layer.

    Science.gov (United States)

    Cheng, Shun-Wen; Han, Ting; Huang, Teng-Yung; Chang Chien, Yu-Hsin; Liu, Cheng-Liang; Tang, Ben Zhong; Liou, Guey-Sheng

    2018-05-30

    A novel aggregation enhanced emission (AEE)-active polyamide TPA-CN-TPE with a high photoluminesence characteristic was successfully synthesized by the direct polymerization of 4-cyanotriphenyl diamine (TPA-CN) and tetraphenylethene (TPE)-containing dicarboxylic acid. The obtained luminescent polyamide plays a significant role as the polymer electret layer in organic field-effect transistors (OFETs)-type memory. The strong green emission of TPA-CN-TPE under ultraviolet (UV) irradiation can be directly absorbed by the pentacene channel, displaying a light-induced programming and voltage-driven erasing organic phototransistor-based nonvolatile memory. Memory window can be effectively manipulated between the programming and erasing states by applying UV light illumination and electrical field, respectively. The photoinduced memory behavior can be maintained for over 10 4 s between these two states with an on/off ratio of 10 4 , and the memory switching can be steadily operated for many cycles. With high photoresponsivity ( R) and photosensitivity ( S), this organic phototransistor integrated with AEE-active polyamide electret layer could serve as an excellent candidate for UV photodetectors in optical applications. For comparison, an AEE-inactive aromatic polyimide TPA-PIS electret with much weaker solid-state emission was also applied in the same OFETs device architecture, but this device did not show any UV-sensitive and UV-induced memory characteristics, which further confirmed the significance of the light-emitting capability of the electret layer.

  9. Spatial memory enhances the evacuation efficiency of virtual pedestrians under poor visibility condition

    Science.gov (United States)

    Ma, Yi; Lee, Eric Wai Ming; Shi, Meng; Kwok Kit Yuen, Richard

    2018-03-01

    Spatial memory is a critical navigation support tool for disoriented evacuees during evacuation under adverse environmental conditions such as dark or smoky conditions. Owing to the complexity of memory, it is challenging to understand the effect of spatial memory on pedestrian evacuation quantitatively. In this study, we propose a simple method to quantitatively represent the evacueeʼs spatial memory about the emergency exit, model the evacuation of pedestrians under the guidance of the spatial memory, and investigate the effect of the evacueeʼs spatial memory on the evacuation from theoretical and physical perspectives. The result shows that (i) a good memory can significantly assist the evacuation of pedestrians under poor visibility conditions, and the evacuation can always succeed when the degree of the memory exceeds a threshold (\\varphi > 0.5); (ii) the effect of memory is superior to that of “follow-the-crowd” under the same environmental conditions; (iii) in the case of multiple exits, the difference in the degree of the memory between evacuees has a significant effect (the greater the difference, the faster the evacuation) for the evacuation under poor visibility conditions. Our study provides a new quantitative insight into the effect of spatial memory on crowd evacuation under poor visibility conditions. Project supported by the Research Grants Council of the Hong Kong Special Administrative Region, China (Grant No. 11203615).

  10. Falling out of time: enhanced memory for scenes presented at behaviorally irrelevant points in time in posttraumatic stress disorder (PTSD).

    Science.gov (United States)

    Levy-Gigi, Einat; Kéri, Szabolcs

    2012-01-01

    Spontaneous encoding of the visual environment depends on the behavioral relevance of the task performed simultaneously. If participants identify target letters or auditory tones while viewing a series of briefly presented natural and urban scenes, they demonstrate effective scene recognition only when a target, but not a behaviorally irrelevant distractor, appears together with the scene. Here, we show that individuals with posttraumatic stress disorder (PTSD), who witnessed the red sludge disaster in Hungary, show the opposite pattern of performance: enhanced recognition of scenes presented together with distractors and deficient recognition of scenes presented with targets. The recognition of trauma-related and neutral scenes was not different in individuals with PTSD. We found a positive correlation between memory for scenes presented with auditory distractors and re-experiencing symptoms (memory intrusions and flashbacks). These results suggest that abnormal encoding of visual scenes at behaviorally irrelevant events might be associated with intrusive experiences by disrupting the flow of time.

  11. Falling out of time: enhanced memory for scenes presented at behaviorally irrelevant points in time in posttraumatic stress disorder (PTSD.

    Directory of Open Access Journals (Sweden)

    Einat Levy-Gigi

    Full Text Available Spontaneous encoding of the visual environment depends on the behavioral relevance of the task performed simultaneously. If participants identify target letters or auditory tones while viewing a series of briefly presented natural and urban scenes, they demonstrate effective scene recognition only when a target, but not a behaviorally irrelevant distractor, appears together with the scene. Here, we show that individuals with posttraumatic stress disorder (PTSD, who witnessed the red sludge disaster in Hungary, show the opposite pattern of performance: enhanced recognition of scenes presented together with distractors and deficient recognition of scenes presented with targets. The recognition of trauma-related and neutral scenes was not different in individuals with PTSD. We found a positive correlation between memory for scenes presented with auditory distractors and re-experiencing symptoms (memory intrusions and flashbacks. These results suggest that abnormal encoding of visual scenes at behaviorally irrelevant events might be associated with intrusive experiences by disrupting the flow of time.

  12. Repeated administration of fresh garlic increases memory retention in rats.

    Science.gov (United States)

    Haider, Saida; Naz, Nosheen; Khaliq, Saima; Perveen, Tahira; Haleem, Darakhshan J

    2008-12-01

    Garlic (Allium sativum) is regarded as both a food and a medicinal herb. Increasing attention has focused on the biological functions and health benefits of garlic as a potentially major dietary component. Chronic garlic administration has been shown to enhance memory function. Evidence also shows that garlic administration in rats affects brain serotonin (5-hydroxytryptamine [5-HT]) levels. 5-HT, a neurotransmitter involved in a number of physiological functions, is also known to enhance cognitive performance. The present study was designed to investigate the probable neurochemical mechanism responsible for the enhancement of memory following garlic administration. Sixteen adult locally bred male albino Wistar rats were divided into control (n = 8) and test (n = 8) groups. The test group was orally administered 250 mg/kg fresh garlic homogenate (FGH), while control animals received an equal amount of water daily for 21 days. Estimation of plasma free and total tryptophan (TRP) and whole brain TRP, 5-HT, and 5-hydroxyindole acetic acid (5-HIAA) was determined by high-performance liquid chromatography with electrochemical detection. For assessment of memory, a step-through passive avoidance paradigm (electric shock avoidance) was used. The results showed that the levels of plasma free TRP significantly increased (P < .01) and plasma total TRP significantly decreased (P < .01) in garlic-treated rats. Brain TRP, 5-HT, and 5-HIAA levels were also significantly increased following garlic administration. A significant improvement in memory function was exhibited by garlic-treated rats in the passive avoidance test. Increased brain 5-HT levels were associated with improved cognitive performance. The present results, therefore, demonstrate that the memory-enhancing effect of garlic may be associated with increased brain 5-HT metabolism in rats. The results further support the use of garlic as a food supplement for the enhancement of memory.

  13. On the persuadability of memory: Is changing people's memories no more than changing their minds?

    Science.gov (United States)

    Nash, Robert A; Wheeler, Rebecca L; Hope, Lorraine

    2015-05-01

    The observation of parallels between the memory distortion and persuasion literatures leads, quite logically, to the appealing notion that people can be 'persuaded' to change their memories. Indeed, numerous studies show that memory can be influenced and distorted by a variety of persuasive tactics, and the theoretical accounts commonly used by researchers to explain episodic and autobiographical memory distortion phenomena can generally predict and explain these persuasion effects. Yet, despite these empirical and theoretical overlaps, explicit reference to persuasion and attitude-change research in the memory distortion literature is surprisingly rare. In this paper, we argue that stronger theoretical foundations are needed to draw the memory distortion and persuasion literatures together in a productive direction. We reason that theoretical approaches to remembering that distinguish (false) beliefs in the occurrence of events from (false) memories of those events - compatible with a source monitoring approach - would be beneficial to this end. Such approaches, we argue, would provide a stronger platform to use persuasion findings to enhance the psychological understanding of memory distortion. © 2014 The British Psychological Society.

  14. Remote memories are enhanced by COMT activity through dysregulation of the endocannabinoid system in the prefrontal cortex.

    Science.gov (United States)

    Scheggia, D; Zamberletti, E; Realini, N; Mereu, M; Contarini, G; Ferretti, V; Managò, F; Margiani, G; Brunoro, R; Rubino, T; De Luca, M A; Piomelli, D; Parolaro, D; Papaleo, F

    2018-04-01

    The prefrontal cortex (PFC) is a crucial hub for the flexible modulation of recent memories (executive functions) as well as for the stable organization of remote memories. Dopamine in the PFC is implicated in both these processes and genetic variants affecting its neurotransmission might control the unique balance between cognitive stability and flexibility present in each individual. Functional genetic variants in the catechol-O-methyltransferase (COMT) gene result in a different catabolism of dopamine in the PFC. However, despite the established role played by COMT genetic variation in executive functions, its impact on remote memory formation and recall is still poorly explored. Here we report that transgenic mice overexpressing the human COMT-Val gene (COMT-Val-tg) present exaggerated remote memories (>50 days) while having unaltered recent memories (remote memories as silencing COMT Val overexpression starting from 30 days after the initial aversive conditioning normalized remote memories. COMT genetic overactivity produced a selective overdrive of the endocannabinoid system within the PFC, but not in the striatum and hippocampus, which was associated with enhanced remote memories. Indeed, acute pharmacological blockade of CB1 receptors was sufficient to rescue the altered remote memory recall in COMT-Val-tg mice and increased PFC dopamine levels. These results demonstrate that COMT genetic variations modulate the retrieval of remote memories through the dysregulation of the endocannabinoid system in the PFC.

  15. Synaesthesia is linked to more vivid and detailed content of autobiographical memories and less fading of childhood memories.

    Science.gov (United States)

    Chin, Taylor; Ward, Jamie

    2017-12-15

    People with synaesthesia have enhanced memory on a wide range of laboratory tests of episodic memory, but very little is known about their real-world memory. This study used a standard measure of autobiographical remembering (the Autobiographical Memory Questionnaire, AMQ) considering four constructs (Recollection, Belief, Impact and Rehearsal) and two time periods (recent memories from adulthood, remote memories from childhood). Synaesthetes reported more Recollection (e.g., sensory detail) and Belief (e.g., confidence) which interacted with time, such that remote memories are reported to be comparatively better preserved in synaesthetes. This cannot be explained by synaesthetes recalling more salient episodes (the groups did not differ in Impact). It suggests instead that childhood memories have a special status in synaesthesia that reflects the different neurodevelopmental trajectory of this group. With regards to Rehearsal, controls tended to report that more recent memories tend to resurface (i.e., adulthood > childhood), but the synaesthetes showed the opposite dissociation (i.e., childhood > adulthood).

  16. Semantic congruency but not temporal synchrony enhances long-term memory performance for audio-visual scenes.

    Science.gov (United States)

    Meyerhoff, Hauke S; Huff, Markus

    2016-04-01

    Human long-term memory for visual objects and scenes is tremendous. Here, we test how auditory information contributes to long-term memory performance for realistic scenes. In a total of six experiments, we manipulated the presentation modality (auditory, visual, audio-visual) as well as semantic congruency and temporal synchrony between auditory and visual information of brief filmic clips. Our results show that audio-visual clips generally elicit more accurate memory performance than unimodal clips. This advantage even increases with congruent visual and auditory information. However, violations of audio-visual synchrony hardly have any influence on memory performance. Memory performance remained intact even with a sequential presentation of auditory and visual information, but finally declined when the matching tracks of one scene were presented separately with intervening tracks during learning. With respect to memory performance, our results therefore show that audio-visual integration is sensitive to semantic congruency but remarkably robust against asymmetries between different modalities.

  17. Noradrenergic enhancement of associative fear memory in humans

    NARCIS (Netherlands)

    Soeter, M.; Kindt, M.

    2011-01-01

    Ample evidence in animals and humans supports the noradrenergic modulation in the formation of emotional memory. However, in humans the effects of stress on emotional memory are traditionally investigated by declarative memory tests (e.g., recall, recognition) for non-associative emotional stimuli

  18. Frontal and temporal lobe contributions to emotional enhancement of memory in behavioral-variant frontotemporal dementia and Alzheimer's disease

    OpenAIRE

    Kumfor, Fiona; Irish, Muireann; Hodges, John R.; Piguet, Olivier

    2014-01-01

    Emotional events gain special priority in how they are remembered, with emotionally arousing events typically recalled more vividly and with greater confidence than non-emotional events. In dementia, memory and emotion processing are affected to varying degrees, however, whether emotional enhancement of memory for complex ecologically-valid events is differentially affected across dementia syndromes remains unclear, with previous studies examining effects of emotion on simple visual recogniti...

  19. Enhancing effects of lithium on memory are not by-products of learning or attentional deficits.

    Science.gov (United States)

    Tsaltas, Eleftheria; Kyriazi, Theodora; Poulopoulou, Cornelia; Kontis, Dimitrios; Maillis, Antonios

    2007-06-18

    We recently reported that chronic lithium (LiCl), at therapeutic plasma levels, enhanced spatial working memory and retention of an aversive contingency. Here we examine the possibility that these effects be secondary to LiCl effects on the ability to ignore irrelevant stimuli or on fear conditioning. In Experiment 1, rats subjected to >30 daily intraperitoneal injections of LiCl (2mmol/kg) or saline underwent conditioned emotional response training (CER: 2 CS pairings with 1-s, 1-mA shock) after 40 pre-exposures either to the CS (latent inhibition-LiCl/latent inhibition-saline, n=8) or to another stimulus (control-LiCl/control-saline, n=8). In Experiment 2, eight LiCl and eight saline animals were trained in on-the-baseline (VI-60s) CER (1-s, 0.15-mA shock in CS-signalled periods) in the Skinner box. In Experiment 1, LiCl animals showed normal latent inhibition. In both experiments, their fear conditioning was unimpaired. Therefore, the previously reported memory improvement under chronic lithium cannot be attributed to changes in the ability to ignore irrelevant stimuli or in fear conditioning.

  20. Enhancing the production effect in memory.

    Science.gov (United States)

    Quinlan, Chelsea K; Taylor, Tracy L

    2013-01-01

    The production effect is the finding that subsequent memory is better for words that are produced than for words that are not produced. Whereas the current literature demonstrates that reading aloud is the most effective form of production, the distinctiveness account used to explain the production effect predicts that there is nothing special about reading aloud per se: Other forms of vocal production that include an additional distinct element should produce even greater subsequent memory benefits than reading aloud. To test this, we presented participants with study words that they were instructed to read aloud loudly, read aloud, or read silently (Experiment 1); sing, read aloud, or read silently (Experiment 2); and sing, read aloud loudly, read aloud, or read silently (Experiment 3). We observed that both reading items aloud loudly (Experiments 1 and 3) and singing items (Experiments 2 and 3) at study resulted in greater subsequent recognition than reading items aloud in a normal voice; singing had a larger memory benefit than reading aloud loudly (Experiment 3). Our findings support the distinctiveness hypothesis by demonstrating that there are other forms of production, such as singing and reading aloud loudly that have a more pronounced effect on memory than reading aloud.

  1. Epigenomic analysis of primary human T cells reveals enhancers associated with TH2 memory cell differentiation and asthma susceptibility

    Science.gov (United States)

    Seumois, Grégory; Chavez, Lukas; Gerasimova, Anna; Lienhard, Matthias; Omran, Nada; Kalinke, Lukas; Vedanayagam, Maria; Ganesan, Asha Purnima V; Chawla, Ashu; Djukanović, Ratko; Ansel, K Mark; Peters, Bjoern; Rao, Anjana; Vijayanand, Pandurangan

    2014-01-01

    A characteristic feature of asthma is the aberrant accumulation, differentiation or function of memory CD4+ T cells that produce type 2 cytokines (TH2 cells). By mapping genome-wide histone modification profiles for subsets of T cells isolated from peripheral blood of healthy and asthmatic individuals, we identified enhancers with known and potential roles in the normal differentiation of human TH1 cells and TH2 cells. We discovered disease-specific enhancers in T cells that differ between healthy and asthmatic individuals. Enhancers that gained the histone H3 Lys4 dimethyl (H3K4me2) mark during TH2 cell development showed the highest enrichment for asthma-associated single nucleotide polymorphisms (SNPs), which supported a pathogenic role for TH2 cells in asthma. In silico analysis of cell-specific enhancers revealed transcription factors, microRNAs and genes potentially linked to human TH2 cell differentiation. Our results establish the feasibility and utility of enhancer profiling in well-defined populations of specialized cell types involved in disease pathogenesis. PMID:24997565

  2. Shattered illusions: the effect of explicit memory mediation on an indirect memory test.

    Science.gov (United States)

    Gooding, P A; Mayes, A R; Meudell, P R

    1999-05-01

    Four experiments were conducted to explore the possible involvement of explicit memory in an indirect memory test in which white noise accompanying old sentences was judged to be quieter than white noise accompanying new sentences (Jacoby, Allan, Collins & Larwill, 1988). Experiment 1 established that this effect lasted up to 1 week. Experiment 2 found that a group of amnesic patients showed a noise effect that was marginally above chance and not significantly less that that of their matched controls after a delay of one day. Effect of time pressure at test (Experiment 3) and divided attention at study (Experiment 4) suggested that the memory processes mediating the noise effect were not automatic, although the possibility that the processes involve enhanced fluency is also discussed.

  3. Semantic representations in the temporal pole predict false memories.

    Science.gov (United States)

    Chadwick, Martin J; Anjum, Raeesa S; Kumaran, Dharshan; Schacter, Daniel L; Spiers, Hugo J; Hassabis, Demis

    2016-09-06

    Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the "semantic hub" of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories.

  4. Semantic representations in the temporal pole predict false memories

    Science.gov (United States)

    Chadwick, Martin J.; Anjum, Raeesa S.; Kumaran, Dharshan; Schacter, Daniel L.; Spiers, Hugo J.; Hassabis, Demis

    2016-01-01

    Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the “semantic hub” of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories. PMID:27551087

  5. Superior Long-Term Synaptic Memory Induced by Combining Dual Pharmacological Activation of PKA and ERK with an Enhanced Training Protocol

    Science.gov (United States)

    Liu, Rong-Yu; Neveu, Curtis; Smolen, Paul; Cleary, Leonard J.; Byrne, John H.

    2017-01-01

    Developing treatment strategies to enhance memory is an important goal of neuroscience research. Activation of multiple biochemical signaling cascades, such as the protein kinase A (PKA) and extracellular signal-regulated kinase (ERK) pathways, is necessary to induce long-term synaptic facilitation (LTF), a correlate of long-term memory (LTM).…

  6. Visual working memory and threat monitoring: Spider fearfuls show disorder-specific change detection

    NARCIS (Netherlands)

    Reinecke, A.; Becker, E.S.; Rinck, M.

    2010-01-01

    Previous studies of biased information processing in anxiety addressed biases of attention and memory, but little is known about the processes taking place between them: visual working memory (VWM) and monitoring of threat. We investigated these processes with a change detection paradigm. In

  7. Memory reactivation improves visual perception.

    Science.gov (United States)

    Amar-Halpert, Rotem; Laor-Maayany, Rony; Nemni, Shlomi; Rosenblatt, Jonathan D; Censor, Nitzan

    2017-10-01

    Human perception thresholds can improve through learning. Here we report findings challenging the fundamental 'practice makes perfect' basis of procedural learning theory, showing that brief reactivations of encoded visual memories are sufficient to improve perceptual discrimination thresholds. Learning was comparable to standard practice-induced learning and was not due to short training per se, nor to an epiphenomenon of primed retrieval enhancement. The results demonstrate that basic perceptual functions can be substantially improved by memory reactivation, supporting a new account of perceptual learning dynamics.

  8. The Influence of Direct and Indirect Speech on Source Memory

    Directory of Open Access Journals (Sweden)

    Anita Eerland

    2018-02-01

    Full Text Available People perceive the same situation described in direct speech (e.g., John said, “I like the food at this restaurant” as more vivid and perceptually engaging than described in indirect speech (e.g., John said that he likes the food at the restaurant. So, if direct speech enhances the perception of vividness relative to indirect speech, what are the effects of using indirect speech? In four experiments, we examined whether the use of direct and indirect speech influences the comprehender’s memory for the identity of the speaker. Participants read a direct or an indirect speech version of a story and then addressed statements to one of the four protagonists of the story in a memory task. We found better source memory at the level of protagonist gender after indirect than direct speech (Exp. 1–3. When the story was rewritten to make the protagonists more distinctive, we also found an effect of speech type on source memory at the level of the individual, with better memory after indirect than direct speech (Exp. 3–4. Memory for the content of the story, however, was not influenced by speech type (Exp. 4. While previous research showed that direct speech may enhance memory for how something was said, we conclude that indirect speech enhances memory for who said what.

  9. CpG in Combination with an Inhibitor of Notch Signaling Suppresses Formalin-Inactivated Respiratory Syncytial Virus-Enhanced Airway Hyperresponsiveness and Inflammation by Inhibiting Th17 Memory Responses and Promoting Tissue-Resident Memory Cells in Lungs.

    Science.gov (United States)

    Zhang, Lei; Li, Hongyong; Hai, Yan; Yin, Wei; Li, Wenjian; Zheng, Boyang; Du, Xiaomin; Li, Na; Zhang, Zhengzheng; Deng, Yuqing; Zeng, Ruihong; Wei, Lin

    2017-05-15

    effective killed RSV vaccine. Using adjuvants to regulate innate and adaptive immune responses could be an effective method to prevent ERD. We evaluated the impact of TLR and Notch signaling on ERD by administering CpG, an agonist of TLR9, in combination with L685,458, an inhibitor of Notch signaling, during FI-RSV immunization. The data showed that treatment of TLR or Notch signaling alone did not suppress FI-RSV-enhanced airway inflammation, while CpG plus L685,458 markedly inhibited ERD. The mechanism appears to involve suppressing Th17 memory responses and promoting tissue-resident memory cells. Moreover, these results suggest that regulation of lung immune memory with adjuvant compounds containing more than one immune-stimulatory molecule may be a good strategy to prevent FI-RSV ERD. Copyright © 2017 American Society for Microbiology.

  10. Estradiol replacement enhances fear memory formation, impairs extinction and reduces COMT expression levels in the hippocampus of ovariectomized female mice.

    Science.gov (United States)

    McDermott, Carmel M; Liu, Dan; Ade, Catherine; Schrader, Laura A

    2015-02-01

    Females experience depression, posttraumatic stress disorder (PTSD), and anxiety disorders at approximately twice the rate of males, but the mechanisms underlying this difference remain undefined. The effect of sex hormones on neural substrates presents a possible mechanism. We investigated the effect of ovariectomy at two ages, before puberty and in adulthood, and 17β-estradiol (E2) replacement administered chronically in drinking water on anxiety level, fear memory formation, and extinction. Based on previous studies, we hypothesized that estradiol replacement would impair fear memory formation and enhance extinction rate. Females, age 4 weeks and 10 weeks, were divided randomly into 4 groups; sham surgery, OVX, OVX+low E2 (200nM), and OVX+high E2 (1000nM). Chronic treatment with high levels of E2 significantly increased anxiety levels measured in the elevated plus maze. In both age groups, high levels of E2 significantly increased contextual fear memory but had no effect on cued fear memory. In addition, high E2 decreased the rate of extinction in both ages. Finally, catechol-O-methyltransferase (COMT) is important for regulation of catecholamine levels, which play a role in fear memory formation and extinction. COMT expression in the hippocampus was significantly reduced by high E2 replacement, implying increased catecholamine levels in the hippocampus of high E2 mice. These results suggest that estradiol enhanced fear memory formation, and inhibited fear memory extinction, possibly stabilizing the fear memory in female mice. This study has implications for a neurobiological mechanism for PTSD and anxiety disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Sleep-related memory consolidation in primary insomnia.

    Science.gov (United States)

    Nissen, Christoph; Kloepfer, Corinna; Feige, Bernd; Piosczyk, Hannah; Spiegelhalder, Kai; Voderholzer, Ulrich; Riemann, Dieter

    2011-03-01

    It has been suggested that healthy sleep facilitates the consolidation of newly acquired memories and underlying brain plasticity. The authors tested the hypothesis that patients with primary insomnia (PI) would show deficits in sleep-related memory consolidation compared to good sleeper controls (GSC). The study used a four-group parallel design (n=86) to investigate the effects of 12 h of night-time, including polysomnographically monitored sleep ('sleep condition' in PI and GSC), versus 12 h of daytime wakefulness ('wake condition' in PI and GSC) on procedural (mirror tracing task) and declarative memory consolidation (visual and verbal learning task). Demographic characteristics and memory encoding did not differ between the groups at baseline. Polysomnography revealed a significantly disturbed sleep profile in PI compared to GSC in the sleep condition. Night-time periods including sleep in GSC were associated with (i) a significantly enhanced procedural and declarative verbal memory consolidation compared to equal periods of daytime wakefulness in GSC and (ii) a significantly enhanced procedural memory consolidation compared to equal periods of daytime wakefulness and night-time sleep in PI. Across retention intervals of daytime wakefulness, no differences between the experimental groups were observed. This pattern of results suggests that healthy sleep fosters the consolidation of new memories, and that this process is impaired for procedural memories in patients with PI. Future work is needed to investigate the impact of treatment on improving sleep and memory. © 2010 European Sleep Research Society.

  12. With sadness comes accuracy; with happiness, false memory: mood and the false memory effect.

    Science.gov (United States)

    Storbeck, Justin; Clore, Gerald L

    2005-10-01

    The Deese-Roediger-McDermott paradigm lures people to produce false memories. Two experiments examined whether induced positive or negative moods would influence this false memory effect. The affect-as-information hypothesis predicts that, on the one hand, positive affective cues experienced as task-relevant feedback encourage relational processing during encoding, which should enhance false memory effects. On the other hand, negative affective cues are hypothesized to encourage item-specific processing at encoding, which should discourage such effects. The results of Experiment 1 are consistent with these predictions: Individuals in negative moods were significantly less likely to show false memory effects than those in positive moods or those whose mood was not manipulated. Experiment 2 introduced inclusion instructions to investigate whether moods had their effects at encoding or retrieval. The results replicated the false memory finding of Experiment 1 and provide evidence that moods influence the accessibility of lures at encoding, rather than influencing monitoring at retrieval of whether lures were actually presented.

  13. Enhanced mechanical properties of linear segmented shape memory poly(urethane-urea) by incorporating flexible PEG400 and rigid piperazine

    Science.gov (United States)

    Zhang, Xiao-Yan; Ma, Yu-Fei; Li, Yong-Gang; Wang, Pin-Pin; Wang, Yuan-Liang; Luo, Yan-Feng

    2012-12-01

    The goal of this study is to design and synthesize a linear segmented shape memory poly(urethane-urea) (SMPUU) that possesses near-body-temperature shape memory temperature ( T tran) and enhanced mechanical properties by incorporating flexible poly(ethylene glycol) 400 (PEG400) to form poly(D,L-lactic acid)-based macrodiols (PDLLA-PEG400-PDLLA) and then rigid piperazine (PPZ) as a chain extender to form the desired SMPUUs (PEG400-PUU-PPZ). PEG400 increased M n while maintaining a lower T g of PDLLA-PEG400-PDLLA, which together with PPZ improved the mechanical properties of PEG400-PUU-PPZ. The obtained optimum SMPUU with enhanced mechanical properties ( σ y = 24.28 MPa; ɛ f = 698%; U f = 181.5 MJ/m3) and a T g of 40.62°C exhibited sound shape memory properties as well, suggesting a promising SMPUU for in vivo biomedical applications.

  14. Consensus: "Can tDCS and TMS enhance motor learning and memory formation?"

    Science.gov (United States)

    Reis, Janine; Robertson, Edwin; Krakauer, John W; Rothwell, John; Marshall, Lisa; Gerloff, Christian; Wassermann, Eric; Pascual-Leone, Alvaro; Hummel, Friedhelm; Celnik, Pablo A; Classen, Joseph; Floel, Agnes; Ziemann, Ulf; Paulus, Walter; Siebner, Hartwig R; Born, Jan; Cohen, Leonardo G

    2008-10-01

    Noninvasive brain stimulation has developed as a promising tool for cognitive neuroscientists. Transcranial magnetic (TMS) and direct current (tDCS) stimulation allow researchers to purposefully enhance or decrease excitability in focal areas of the brain. The purpose of this paper is to review information on the use of TMS and tDCS as research tools to facilitate motor memory formation, motor performance and motor learning in healthy volunteers. Studies implemented so far have mostly focused on the ability of TMS and tDCS to elicit relatively short lasting motor improvements and the mechanisms underlying these changes have been only partially investigated. Despite limitations including the scarcity of data, work that has been already accomplished raises the exciting hypothesis that currently available noninvasive transcranial stimulation techniques could modulate motor learning and memory formation in healthy humans and potentially in patients with neurological and psychiatric disorders.

  15. Vitamin B1-deficient mice show impairment of hippocampus-dependent memory formation and loss of hippocampal neurons and dendritic spines: potential microendophenotypes of Wernicke-Korsakoff syndrome.

    Science.gov (United States)

    Inaba, Hiroyoshi; Kishimoto, Takuya; Oishi, Satoru; Nagata, Kan; Hasegawa, Shunsuke; Watanabe, Tamae; Kida, Satoshi

    2016-12-01

    Patients with severe Wernicke-Korsakoff syndrome (WKS) associated with vitamin B1 (thiamine) deficiency (TD) show enduring impairment of memory formation. The mechanisms of memory impairment induced by TD remain unknown. Here, we show that hippocampal degeneration is a potential microendophenotype (an endophenotype of brain disease at the cellular and synaptic levels) of WKS in pyrithiamine-induced thiamine deficiency (PTD) mice, a rodent model of WKS. PTD mice show deficits in the hippocampus-dependent memory formation, although they show normal hippocampus-independent memory. Similarly with WKS, impairments in memory formation did not recover even at 6 months after treatment with PTD. Importantly, PTD mice exhibit a decrease in neurons in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus and reduced density of wide dendritic spines in the DG. Our findings suggest that TD induces hippocampal degeneration, including the loss of neurons and spines, thereby leading to enduring impairment of hippocampus-dependent memory formation.

  16. Vitamin B1-deficient mice show impairment of hippocampus-dependent memory formation and loss of hippocampal neurons and dendritic spines: potential microendophenotypes of Wernicke–Korsakoff syndrome

    Science.gov (United States)

    Inaba, Hiroyoshi; Kishimoto, Takuya; Oishi, Satoru; Nagata, Kan; Hasegawa, Shunsuke; Watanabe, Tamae; Kida, Satoshi

    2016-01-01

    Patients with severe Wernicke–Korsakoff syndrome (WKS) associated with vitamin B1 (thiamine) deficiency (TD) show enduring impairment of memory formation. The mechanisms of memory impairment induced by TD remain unknown. Here, we show that hippocampal degeneration is a potential microendophenotype (an endophenotype of brain disease at the cellular and synaptic levels) of WKS in pyrithiamine-induced thiamine deficiency (PTD) mice, a rodent model of WKS. PTD mice show deficits in the hippocampus-dependent memory formation, although they show normal hippocampus-independent memory. Similarly with WKS, impairments in memory formation did not recover even at 6 months after treatment with PTD. Importantly, PTD mice exhibit a decrease in neurons in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus and reduced density of wide dendritic spines in the DG. Our findings suggest that TD induces hippocampal degeneration, including the loss of neurons and spines, thereby leading to enduring impairment of hippocampus-dependent memory formation. PMID:27576603

  17. Context-specific activation of hippocampus and SN/VTA by reward is related to enhanced long-term memory for embedded objects.

    Science.gov (United States)

    Loh, Eleanor; Kumaran, Dharshan; Koster, Raphael; Berron, David; Dolan, Ray; Duzel, Emrah

    2016-10-01

    Animal studies indicate that hippocampal representations of environmental context modulate reward-related processing in the substantia nigra and ventral tegmental area (SN/VTA), a major origin of dopamine in the brain. Using functional magnetic resonance imaging (fMRI) in humans, we investigated the neural specificity of context-reward associations under conditions where the presence of perceptually similar neutral contexts imposed high demands on a putative hippocampal function, pattern separation. The design also allowed us to investigate how contextual reward enhances long-term memory for embedded neutral objects. SN/VTA activity underpinned specific context-reward associations in the face of perceptual similarity. A reward-related enhancement of long-term memory was restricted to the condition where the rewarding and the neutral contexts were perceptually similar, and in turn was linked to co-activation of the hippocampus (subfield DG/CA3) and SN/VTA. Thus, an ability of contextual reward to enhance memory for focal objects is closely linked to context-related engagement of hippocampal-SN/VTA circuitry. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  18. MEMORY MODULATION

    Science.gov (United States)

    Roozendaal, Benno; McGaugh, James L.

    2011-01-01

    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

  19. How music training enhances working memory: a cerebrocerebellar blending mechanism that can lead equally to scientific discovery and therapeutic efficacy in neurological disorders.

    Science.gov (United States)

    Vandervert, Larry

    2015-01-01

    Following in the vein of studies that concluded that music training resulted in plastic changes in Einstein's cerebral cortex, controlled research has shown that music training (1) enhances central executive attentional processes in working memory, and (2) has also been shown to be of significant therapeutic value in neurological disorders. Within this framework of music training-induced enhancement of central executive attentional processes, the purpose of this article is to argue that: (1) The foundational basis of the central executive begins in infancy as attentional control during the establishment of working memory, (2) In accordance with Akshoomoff, Courchesne and Townsend's and Leggio and Molinari's cerebellar sequence detection and prediction models, the rigors of volitional control demands of music training can enhance voluntary manipulation of information in thought and movement, (3) The music training-enhanced blending of cerebellar internal models in working memory as can be experienced as intuition in scientific discovery (as Einstein often indicated) or, equally, as moments of therapeutic advancement toward goals in the development of voluntary control in neurological disorders, and (4) The blending of internal models as in (3) thus provides a mechanism by which music training enhances central executive processes in working memory that can lead to scientific discovery and improved therapeutic outcomes in neurological disorders. Within the framework of Leggio and Molinari's cerebellar sequence detection model, it is determined that intuitive steps forward that occur in both scientific discovery and during therapy in those with neurological disorders operate according to the same mechanism of adaptive error-driven blending of cerebellar internal models. It is concluded that the entire framework of the central executive structure of working memory is a product of the cerebrocerebellar system which can, through the learning of internal models

  20. Enhancing long-term memory with stimulation tunes visual attention in one trial.

    Science.gov (United States)

    Reinhart, Robert M G; Woodman, Geoffrey F

    2015-01-13

    Scientists have long proposed that memory representations control the mechanisms of attention that focus processing on the task-relevant objects in our visual field. Modern theories specifically propose that we rely on working memory to store the object representations that provide top-down control over attentional selection. Here, we show that the tuning of perceptual attention can be sharply accelerated after 20 min of noninvasive brain stimulation over medial-frontal cortex. Contrary to prevailing theories of attention, these improvements did not appear to be caused by changes in the nature of the working memory representations of the search targets. Instead, improvements in attentional tuning were accompanied by changes in an electrophysiological signal hypothesized to index long-term memory. We found that this pattern of effects was reliably observed when we stimulated medial-frontal cortex, but when we stimulated posterior parietal cortex, we found that stimulation directly affected the perceptual processing of the search array elements, not the memory representations providing top-down control. Our findings appear to challenge dominant theories of attention by demonstrating that changes in the storage of target representations in long-term memory may underlie rapid changes in the efficiency with which humans can find targets in arrays of objects.

  1. Hypothalamic-pituitary-adrenal axis reactivity to psychological stress and memory in middle-aged women: high responders exhibit enhanced declarative memory performance.

    Science.gov (United States)

    Domes, G; Heinrichs, M; Reichwald, U; Hautzinger, M

    2002-10-01

    According to recent studies, elevated cortisol levels are associated with impaired declarative memory performance. This specific effect of cortisol has been shown in several studies using pharmacological doses of cortisol. The present study was designed to determine the effects of endogenously stimulated cortisol secretion on memory performance in healthy middle-aged women. For psychological stress challenging, we employed the Trier Social Stress Test (TSST). Subjects were assigned to either the TSST or a non-stressful control condition. Declarative and non-declarative memory performance was measured by a combined priming-free-recall-task. No significant group differences were found for memory performance. Post hoc analyses of variance indicated that regardless of experimental condition the subjects with remarkably high cortisol increase in response to the experimental procedure (high responders) showed increased memory performance in the declarative task compared to subjects with low cortisol response (low responders). The results suggest that stress-induced cortisol failed to impair memory performance. The results are discussed with respect to gender-specific effects and modulatory effects of the sympathetic nervous system and psychological variables. Copyright 2002 Elsevier Science Ltd.

  2. D-Cycloserine Administered Directly to Infralimbic Medial Prefrontal Cortex Enhances Extinction Memory in Sucrose-Seeking Animals

    NARCIS (Netherlands)

    Peters, J.; de Vries, T.J.

    2013-01-01

    d-Cycloserine (DCS), a co-agonist at the N-methyl-D-aspartate (NMDA) receptor, has proven to be an effective adjunct to cognitive behavioral therapies that utilize extinction. This pharmacological-based enhancement of extinction memory has been primarily demonstrated in neuropsychiatric disorders

  3. Music, memory and emotion

    OpenAIRE

    J?ncke, Lutz

    2008-01-01

    Because emotions enhance memory processes and music evokes strong emotions, music could be involved in forming memories, either about pieces of music or about episodes and information associated with particular music. A recent study in BMC Neuroscience has given new insights into the role of emotion in musical memory. Music has a prominent role in the everyday life of many people. Whether it is for recreation, distraction or mood enhancement, a lot of people listen to music from early in t...

  4. Enhancing memory for lists by grouped presentation and rehearsal: a pilot study in healthy subjects with unexpected results.

    Science.gov (United States)

    Hoppe, Christian; Stojanovic, Jelena; Elger, Christian E

    2009-12-01

    List learning is probably the most established paradigm for the psychometric evaluation of episodic memory deficits in different neuropsychiatric conditions including epilepsy. Strategies which are capable of increasing the test performance might be promising candidates for a therapeutic improvement of daily memory performance. Based on the classical 'temporal grouping effect' we wanted to evaluate the memory-enhancing potential of disentangling perceiving, rehearsing and encoding by temporally grouped presentation and group-wise reproduction during acquisition. According to the ethical principle of subsidiary the study was performed in healthy adolescents (N=126) before setting-up a patient study. Subjects had to learn a list of 12 semantically unrelated nouns and a list of 12 figures during two acquisition trials under one of four experimental conditions defined by the size of presented item groups (GS): GS=1 (single items, i.e., 12 x 1 item), GS=3 (4 x 3 items), GS=6 (2 x 6 items), and GS=12 (standard presentation mode, i.e., 1 x 12 items). Repeated measures MANOVA confirmed a positive effect of smaller GS on acquisition performance but the grouping condition obtained no effect on immediate and delayed free recall or on yes/no recognition. For verbal retention, GS=12 even showed a tendency toward an advantage as compared to GS=3. Although appearing reasonable and promising, facilitating acquisition during list learning by temporal grouping and grouped overt rehearsal turned out to be ineffective with regard to long-term memory encoding and retrieval. A strategy however which fails in healthy subjects is unlikely to obtain a therapeutic potential in patients with memory deficits.

  5. Emotional arousal and memory after deep encoding.

    Science.gov (United States)

    Leventon, Jacqueline S; Camacho, Gabriela L; Ramos Rojas, Maria D; Ruedas, Angelica

    2018-05-22

    Emotion often enhances long-term memory. One mechanism for this enhancement is heightened arousal during encoding. However, reducing arousal, via emotion regulation (ER) instructions, has not been associated with reduced memory. In fact, the opposite pattern has been observed: stronger memory for emotional stimuli encoded with an ER instruction to reduce arousal. This pattern may be due to deeper encoding required by ER instructions. In the current research, we examine the effects of emotional arousal and deep-encoding on memory across three studies. In Study 1, adult participants completed a writing task (deep-encoding) for encoding negative, neutral, and positive picture stimuli, whereby half the emotion stimuli had the ER instruction to reduce the emotion. Memory was strong across conditions, and no memory enhancement was observed for any condition. In Study 2, adult participants completed the same writing task as Study 1, as well as a shallow-encoding task for one-third of negative, neutral, and positive trials. Memory was strongest for deep vs. shallow encoding trials, with no effects of emotion or ER instruction. In Study 3, adult participants completed a shallow-encoding task for negative, neutral, and positive stimuli, with findings indicating enhanced memory for negative emotional stimuli. Findings suggest that deep encoding must be acknowledged as a source of memory enhancement when examining manipulations of emotion-related arousal. Copyright © 2018. Published by Elsevier B.V.

  6. Reward acts on the pFC to enhance distractor resistance of working memory representations

    NARCIS (Netherlands)

    Fallon, S.J.; Cools, R.

    2014-01-01

    Working memory and reward processing are often thought to be separate, unrelated processes. However, most daily activities involve integrating these two types of information, and the two processes rarely, if ever, occur in isolation. Here, we show that working memory and reward interact in a

  7. The influence of learning methods on collaboration: prior repeated retrieval enhances retrieval organization, abolishes collaborative inhibition, and promotes post-collaborative memory.

    Science.gov (United States)

    Congleton, Adam R; Rajaram, Suparna

    2011-11-01

    Research on collaborative memory has unveiled the counterintuitive yet robust phenomenon that collaboration impairs group recall. A candidate explanation for this collaborative inhibition effect is the disruption of people's idiosyncratic retrieval strategies during collaboration, and it is hypothesized that employing methods that improve one's organization protects against retrieval disruption. Here it is investigated how one's learning method during the study phase--defined as either repeatedly studying or repeatedly retrieving information--influences retrieval organization and what effects this has on collaborative recall and post-collaborative individual recall. Results show that repeated retrieval consistently eliminated collaborative inhibition. This enabled participants to gain the most from re-exposure to materials recalled by their partners that they themselves did not recall and led to improvements in their individual memory following collaboration. This repeated retrieval advantage stemmed from the preferential manner in which this learning method strengthened retrieval organization. Findings are also discussed that reveal a relationship between retrieval organization and the interaction observed between learning method and short versus long delay seen in the testing effect literature. Finally, results show that the elusive benefits of cross-cuing during collaboration may be best detected with a longer study-test delay. Together, these findings illuminate when and how collaboration can enhance memory.

  8. Supplementation with zinc in rats enhances memory and reverses an age-dependent increase in plasma copper.

    Science.gov (United States)

    Sandusky-Beltran, Leslie A; Manchester, Bryce L; McNay, Ewan C

    2017-08-30

    Zinc and copper are essential trace elements. Dyshomeostasis in these two metals has been observed in Alzheimer's disease, which causes profound cognitive impairment. Insulin therapy has been shown to enhance cognitive performance; however, recent data suggest that this effect may be at least in part due to the inclusion of zinc in the insulin formulation used. Zinc plays a key role in regulation of neuronal glutamate signaling, suggesting a possible link between zinc and memory processes. Consistent with this, zinc deficiency causes cognitive impairments in children. The effect of zinc supplementation on short- and long-term recognition memory, and on spatial working memory, was explored in young and adult male Sprague Dawley rats. After behavioral testing, hippocampal and plasma zinc and copper were measured. Age increased hippocampal zinc and copper, as well as plasma copper, and decreased plasma zinc. An interaction between age and treatment affecting plasma copper was also found, with zinc supplementation reversing elevated plasma copper concentration in adult rats. Zinc supplementation enhanced cognitive performance across tasks. These data support zinc as a plausible therapeutic intervention to ameliorate cognitive impairment in disorders characterized by alterations in zinc and copper, such as Alzheimer's disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Effect of yogic education system and modern education system on memory.

    Science.gov (United States)

    Rangan, R; Nagendra, Hr; Bhat, G Ramachandra

    2009-07-01

    Memory is more associated with the temporal cortex than other cortical areas. The two main components of memory are spatial and verbal which relate to right and left hemispheres of the brain, respectively. Many investigations have shown the beneficial effects of yoga on memory and temporal functions of the brain. This study was aimed at comparing the effect of one Gurukula Education System (GES) school based on a yoga way of life with a school using the Modern Education System (MES) on memory. Forty nine boys of ages ranging from 11-13 years were selected from each of two residential schools, one MES and the other GES, providing similar ambiance and daily routines. The boys were matched for age and socioeconomic status. The GES educational program is based around integrated yoga modules while the MES provides a conventional modern education program. Memory was assessed by means of standard spatial and verbal memory tests applicable to Indian conditions before and after an academic year. Between groups there was matching at start of the academic year, while after it the GES boys showed significant enhancement in both verbal and visual memory scores than MES boys (P < 0.001, Mann-Whitney test). The present study showed that the GES meant for total personality development adopting yoga way of life is more effective in enhancing visual and verbal memory scores than the MES.

  10. The impact of emotion intensity on recognition memory: Valence polarity matters.

    Science.gov (United States)

    Meng, Xianxin; Zhang, Ling; Liu, Wenwen; Ding, XinSheng; Li, Hong; Yang, Jiemin; Yuan, JiaJin

    2017-06-01

    Although the effects of emotion of different emotional intensity on memory have been investigated, it remain unclear whether the influence of emotional intensity on memory varies depending on the stimulus valence polarity (i.e., positive or negative). To address this, event-related potentials were recorded when subjects performed a continuous old/new discrimination task, for highly negative (HN), mildly negative (MN) and neutral pictures in the negative session; and for highly positive (HP), mildly positive (MP) and neutral pictures in the positive session. The results showed that relative to neutral stimuli, both HN and MN stimuli showed increased memory discrimination scores, and enhanced old/new effect in early FN400 (Frontal Negativity), but not late positive component (LPC) amplitudes. By contrast, relative to MP stimuli, HP and neutral stimuli showed increased memory discrimination scores and enhanced old/new effect in LPC but not FN400 amplitudes. Additionally, we observed a significant positive correlation between the memory discrimination score and the old/new effect in the amplitudes of the FN400 and LPC, respectively. These results indicate that both HN and MN stimuli were remembered better than neutral stimuli; whereas the recognition was worse for MP stimuli than Neutral and HP stimuli. In conclusion, in the present study, we observed that the effect of emotion intensity on memory depends on the stimulus valence polarity. Copyright © 2017. Published by Elsevier B.V.

  11. Naps in school can enhance the duration of declarative memories learned by adolescents

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    Nathalia eLemos

    2014-06-01

    Full Text Available Sleep helps the consolidation of declarative memories in the laboratory, but the pro-mnemonic effect of daytime naps in schools is yet to be fully characterized. While a few studies indicate that sleep can indeed benefit school learning, it remains unclear how best to use it. Here we set out to evaluate the influence of daytime naps on the duration of declarative memories learned in school by students of 10-15 years old. A total of 584 students from 6th grade were investigated. Students within a regular classroom were exposed to a 15-minute lecture on new declarative contents, absent from the standard curriculum for this age group. The students were then randomly sorted into nap and non-nap groups. Students in the nap group were conducted to a quiet room with mats, received sleep masks and were invited to sleep. At the same time, students in the non-nap group attended regular school classes given by their usual teacher (Experiment I, or English classes given by another experimenter (Experiment II. In Experiment I (n=371, students were pre-tested on lecture-related contents before the lecture, were invited to nap for up to 2 hours, and after 1, 2 or 5 days received surprise tests with similar content but different wording and question order. In Experiment II (n=213, students were invited to nap for up to 50 minutes (duration of a regular class; surprise tests were applied immediately after the lecture, and repeated after 5, 30 or 110 days. Experiment I showed a significant ~10% gain in test scores for both nap and non-nap groups 1 day after learning, in comparison with pre-test scores. This gain was sustained in the nap group after 2 and 5 days, but in the non-nap group it decayed completely after 5 days. In Experiment II, the nap group showed significantly higher scores than the non-nap group at all times tested, thus precluding specific conclusions. The results suggest that sleep can be used to enhance the duration of memory contents learned in

  12. Double polymer sheathed carbon nanotube supercapacitors show enhanced cycling stability

    Science.gov (United States)

    Zhao, Wenqi; Wang, Shanshan; Wang, Chunhui; Wu, Shiting; Xu, Wenjing; Zou, Mingchu; Ouyang, An; Cao, Anyuan; Li, Yibin

    2015-12-01

    Pseudo-materials are effective in boosting the specific capacitance of supercapacitors, but during service their degradation may also be very strong, causing reduced cycling stability. Here, we show that a carbon nanotube sponge grafted by two conventional pseudo-polymer layers in sequence can serve as a porous supercapacitor electrode with significantly enhanced cycling stability compared with single polymer grafting. Creating conformal polymer coatings on the nanotube surface and the resulting double-sheath configuration are important structural factors leading to the enhanced performance. Combining different polymers as double sheaths as reported here might be a potential route to circumvent the dilemma of pseudo-materials, and to simultaneously improve the capacitance and stability for various energy storage devices.Pseudo-materials are effective in boosting the specific capacitance of supercapacitors, but during service their degradation may also be very strong, causing reduced cycling stability. Here, we show that a carbon nanotube sponge grafted by two conventional pseudo-polymer layers in sequence can serve as a porous supercapacitor electrode with significantly enhanced cycling stability compared with single polymer grafting. Creating conformal polymer coatings on the nanotube surface and the resulting double-sheath configuration are important structural factors leading to the enhanced performance. Combining different polymers as double sheaths as reported here might be a potential route to circumvent the dilemma of pseudo-materials, and to simultaneously improve the capacitance and stability for various energy storage devices. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr05978j

  13. Cigarette smoking might impair memory and sleep quality

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    Jui-Ting Liu

    2013-05-01

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

  14. Learning and Overnight Retention in Declarative Memory in Specific Language Impairment

    Science.gov (United States)

    Lukács, Ágnes; Kemény, Ferenc; Lum, Jarrad A. G.; Ullman, Michael T.

    2017-01-01

    We examined learning and retention in nonverbal and verbal declarative memory in Hungarian children with (n = 21) and without (n = 21) SLI. Recognition memory was tested both 10 minutes and one day after encoding. On nonverbal items, only the children with SLI improved overnight, with no resulting group differences in performance. In the verbal domain, the children with SLI consistently showed worse performance than the typically-developing children, but the two groups showed similar overnight changes. The findings suggest the possibility of spared or even enhanced declarative memory consolidation in SLI. PMID:28046095

  15. Cognitive-Enhancing Effect of Dianthus superbus var. Longicalycinus on Scopolamine-Induced Memory Impairment in Mice.

    Science.gov (United States)

    Weon, Jin Bae; Jung, Youn Sik; Ma, Choong Je

    2016-05-01

    Dianthus superbus (D. superbus) is a traditional crude drug used for the treatment of urethritis, carbuncles and carcinomas. The objective of this study was to confirm the cognitive enhancing effect of D. superbus in memory impairment induced mice and to elucidate the possible potential mechanism. Effect of D. superbus on scopolamine induced memory impairment on mice was evaluated using the Morris water maze and passive avoidance tests. We also investigated acetylcholinesterase (AChE) activity and brain-derived neurotropic factor (BDNF) expression in scopolamine-induced mice. HPLC-DAD analysis was performed to identify active compounds in D. superbus. The results revealed that D. superbus attenuated the learning and memory impairment induced by scopolamine. D. superbus also inhibited AChE levels in the hippocampi of the scopolamine-injected mice. Moreover, D. superbus increased BDNF expression in the hippocampus. Eight compounds were identified using HPLC-DAD analysis. The content of 4-hydroxyphenyl acetic acid was higher than contents of other compounds. These results indicated that D. superbus improved memory functioning accompanied by inhibition of AChE and upregulation of BDNF, suggesting that D. superbus may be a useful therapeutic agent for the prevention or treatment of Alzheimer's disease.

  16. Enhancing memory and activities of daily living in patients with early Alzheimer's disease using memory stimulation intervention: A randomized controlled trial

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    Swati Bajpai

    2017-01-01

    Full Text Available Objective: The objective of this study was to assess the effectiveness of memory stimulation intervention added to donepezil treatment as compared to donepezil alone in patients with early Alzheimer's disease (eAD. Materials and Methods: Patients in the combined treatment group (CTG = 21 received standard dosages of donepezil and weekly memory stimulation activities sessions for 2 months, whereas the treatment as usual group (TAU = 22 received only standard dosages of donepezil. Each session had extensive tasks on memory and its implied practice on instrumental activities of daily living. After 8 sessions, both groups were evaluated for changes in memory and functional outcomes by administering the mini-mental state examination (MMSE, memory (Postgraduate Institute of Memory Scale, and instrumental activities of daily living scale (IADLS. This trial was registered on the Clinical Trials Registry - India (CTRI/2014/04/004550. Results: Statistical analysis was done using independent t-test, which revealed a significant difference between the groups on MMSE, memory, and IADLS post intervention. The MMSE score in the TAU group, while it increased in the CTG group by 4 points. A similar trend was evident in the memory and IADLS scores as well. Effect size in the CTG group was relatively large as compared to the TAU group where the effects were small and negative on some outcomes. Conclusion: The CTG group showed positive treatment effect on cognitive tests suggesting that combined memory stimulation and donepezil treatment has potential to improve the cognitive and functional performance of patients with eAD.

  17. Repetition Enhancement of Amygdala and Visual Cortex Functional Connectivity Reflects Nonconscious Memory for Negative Visual Stimuli.

    Science.gov (United States)

    Kark, Sarah M; Slotnick, Scott D; Kensinger, Elizabeth A

    2016-12-01

    Most studies using a recognition memory paradigm examine the neural processes that support the ability to consciously recognize past events. However, there can also be nonconscious influences from the prior study episode that reflect repetition suppression effects-a reduction in the magnitude of activity for repeated presentations of stimuli-that are revealed by comparing neural activity associated with forgotten items to correctly rejected novel items. The present fMRI study examined the effect of emotional valence (positive vs. negative) on repetition suppression effects. Using a standard recognition memory task, 24 participants viewed line drawings of previously studied negative, positive, and neutral photos intermixed with novel line drawings. For each item, participants made an old-new recognition judgment and a sure-unsure confidence rating. Collapsed across valence, repetition suppression effects were found in ventral occipital-temporal cortex and frontal regions. Activity levels in the majority of these regions were not modulated by valence. However, repetition enhancement of the amygdala and ventral occipital-temporal cortex functional connectivity reflected nonconscious memory for negative items. In this study, valence had little effect on activation patterns but had a larger effect on functional connectivity patterns that were markers of nonconscious memory. Beyond memory and emotion, these findings are relevant to other cognitive and social neuroscientists that utilize fMRI repetition effects to investigate perception, attention, social cognition, and other forms of learning and memory.

  18. Music and memory

    OpenAIRE

    Haefliger, Anna Berenika

    2013-01-01

    Abstract: Music and its different forms of use seem to benefit people in a number of ways. Research has suggested that extensive musical practice and musical listening enhances mental functioning in healthy adults and patients with neurodegenerative disease. Yet, the findings presented have not yet examined the effects both musical training and stimuli enhancement have on episodic memory recognition. 20 musicians and 20 non-musicians took part in an episodic memory task which evaluated m...

  19. Method for training honeybees to respond to olfactory stimuli and enhancement of memory retention therein

    Science.gov (United States)

    McCade, Kirsten J.; Wingo, Robert M.; Haarmann, Timothy K.; Sutherland, Andrew; Gubler, Walter D.

    2015-12-15

    A specialized conditioning protocol for honeybees that is designed for use within a complex agricultural ecosystem. This method ensures that the conditioned bees will be less likely to exhibit a conditioned response to uninfected plants, a false positive response that would render such a biological sensor unreliable for agricultural decision support. Also described is a superboosting training regime that allows training without the aid of expensive equipment and protocols for training in out in the field. Also described is a memory enhancing cocktail that aids in long term memory retention of a vapor signature. This allows the bees to be used in the field for longer durations and with fewer bees trained overall.

  20. Effects of Sleep on Word Pair Memory in Children – Separating Item and Source Memory Aspects

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    Jing-Yi Wang

    2017-09-01

    Full Text Available Word paired-associate learning is a well-established task to demonstrate sleep-dependent memory consolidation in adults as well as children. Sleep has also been proposed to benefit episodic features of memory, i.e., a memory for an event (item bound into the spatiotemporal context it has been experienced in (source. We aimed to explore if sleep enhances word pair memory in children by strengthening the episodic features of the memory, in particular. Sixty-one children (8–12 years studied two lists of word pairs with 1 h in between. Retrieval testing comprised cued recall of the target word of each word pair (item memory and recalling in which list the word pair had appeared in (source memory. Retrieval was tested either after 1 h (short retention interval or after 11 h, with this long retention interval covering either nocturnal sleep or daytime wakefulness. Compared with the wake interval, sleep enhanced separate recall of both word pairs and the lists per se, while recall of the combination of the word pair and the list it had appeared in remained unaffected by sleep. An additional comparison with adult controls (n = 37 suggested that item-source bound memory (combined recall of word pair and list is generally diminished in children. Our results argue against the view that the sleep-induced enhancement in paired-associate learning in children is a consequence of sleep specifically enhancing the episodic features of the memory representation. On the contrary, sleep in children might strengthen item and source representations in isolation, while leaving the episodic memory representations (item-source binding unaffected.

  1. Developmental trends in adaptive memory.

    Science.gov (United States)

    Otgaar, Henry; Howe, Mark L; Smeets, Tom; Garner, Sarah R

    2014-01-01

    Recent studies have revealed that memory is enhanced when information is processed for fitness-related purposes. The main objective of the current experiments was to test developmental trends in the evolutionary foundation of memory using different types of stimuli and paradigms. In Experiment 1, 11-year-olds and adults were presented with neutral, negative, and survival-related DRM word lists. We found a memory benefit for the survival-related words and showed that false memories were more likely to be elicited for the survival-related word lists than for the other lists. Experiment 2 examined developmental trends in the survival processing paradigm using neutral, negative, and survival-related pictures. A survival processing advantage was found for survival-related pictures in adults, for negative pictures in 11/12-year-olds, and for neutral pictures in 7/8-year-olds. In Experiment 3, 11/12-year-olds and adults had to imagine the standard survival scenario or an adapted survival condition (or pleasantness condition) that was designed to reduce the possibilities for elaborative processing. We found superior memory retention for both survival scenarios in children and adults. Collectively, our results evidently show that the survival processing advantage is developmentally invariant and that certain proximate mechanisms (elaboration and distinctiveness) underlie these developmental trends.

  2. Cognitive enhancing effect of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers on learning and memory

    Science.gov (United States)

    Nade, V. S.; Kawale, L. A.; Valte, K. D.; Shendye, N. V.

    2015-01-01

    Objective: The present study was designed to investigate cognitive enhancing property of angiotensin-converting enzymes inhibitors (ACEI) and angiotensin receptor blockers (ARBs) in rats. Materials and Methods: The elevated plus maze (EPM), passive avoidance test (PAT), and water maze test (WMT) were used to assess cognitive enhancing activity in young and aged rats. Ramipril (10 mg/kg, p.o.), perindopril (10 mg/kg, i.p), losartan (20 mg/kg, i.p), and valsartan (20 mg/kg, p.o) were administered to assess their effect on learning and memory. Scopolamine (1 mg/kg, i.p) was used to impair cognitive function. Piracetam (200 mg/kg, i.p) was used as reference drug. Results: All the treatments significantly attenuated amnesia induced by aging and scopolamine. In EPM, aged and scopolamine-treated rats showed an increase in transfer latency (TL) whereas, ACEI and ARBs showed a significant decrease in TL. Treatment with ACEI and ARBs significantly increased step down latencies and decreased latency to reach the platform in target quadrant in young, aged and scopolamine-treated animals in PAT and WMT, respectively. The treatments inhibited acetylcholinesterase (AChE) enzyme in the brain. Similarly, all the treatments attenuated scopolamine-induced lipid peroxidation and normalize antioxidant enzymes. Conclusion: The results suggest that the cognitive enhancing effect of ACEI and ARBs may be due to inhibition of AChE or by regulation of antioxidant system or increase in formation of angiotensin IV. PMID:26069362

  3. Contributions of the Nucleus Accumbens Shell in Mediating the Enhancement in Memory Following Noradrenergic Activation of Either the Amygdala or Hippocampus

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    Erin C. Kerfoot

    2018-02-01

    Full Text Available The nucleus accumbens shell is a site of converging inputs during memory processing for emotional events. The accumbens receives input from the nucleus of the solitary tract (NTS regarding changes in peripheral autonomic functioning following emotional arousal. The shell also receives input from the amygdala and hippocampus regarding affective and contextual attributes of new learning experiences. The successful encoding of affect or context is facilitated by activating noradrenergic systems in either the amygdala or hippocampus. Recent findings indicate that memory enhancement produced by activating NTS neurons, is attenuated by suppressing accumbens functioning after learning. This finding illustrates the significance of the shell in integrating information from the periphery to modulate memory for arousing events. However, it is not known if the accumbens shell plays an equally important role in consolidating information that is initially processed in the amygdala and hippocampus. The present study determined if the convergence of inputs from these limbic regions within the nucleus accumbens contributes to successful encoding of emotional events into memory. Male Sprague-Dawley rats received bilateral cannula implants 2 mm above the accumbens shell and a second bilateral implant 2 mm above either the amygdala or hippocampus. The subjects were trained for 6 days to drink from a water spout. On day 7, a 0.35 mA footshock was initiated as the rat approached the spout and was terminated once the rat escaped into a white compartment. Subjects were then given intra-amygdala or hippocampal infusions of PBS or a dose of norepinephrine (0.2 μg previously shown to enhance memory. Later, all subjects were given intra-accumbens infusion of muscimol to functionally inactivate the shell. Muscimol inactivation of the accumbens shell was delayed to allow sufficient time for norepinephrine to activate intracellular cascades that lead to long-term synaptic

  4. Contributions of the Nucleus Accumbens Shell in Mediating the Enhancement in Memory Following Noradrenergic Activation of Either the Amygdala or Hippocampus.

    Science.gov (United States)

    Kerfoot, Erin C; Williams, Cedric L

    2018-01-01

    The nucleus accumbens shell is a site of converging inputs during memory processing for emotional events. The accumbens receives input from the nucleus of the solitary tract (NTS) regarding changes in peripheral autonomic functioning following emotional arousal. The shell also receives input from the amygdala and hippocampus regarding affective and contextual attributes of new learning experiences. The successful encoding of affect or context is facilitated by activating noradrenergic systems in either the amygdala or hippocampus. Recent findings indicate that memory enhancement produced by activating NTS neurons, is attenuated by suppressing accumbens functioning after learning. This finding illustrates the significance of the shell in integrating information from the periphery to modulate memory for arousing events. However, it is not known if the accumbens shell plays an equally important role in consolidating information that is initially processed in the amygdala and hippocampus. The present study determined if the convergence of inputs from these limbic regions within the nucleus accumbens contributes to successful encoding of emotional events into memory. Male Sprague-Dawley rats received bilateral cannula implants 2 mm above the accumbens shell and a second bilateral implant 2 mm above either the amygdala or hippocampus. The subjects were trained for 6 days to drink from a water spout. On day 7, a 0.35 mA footshock was initiated as the rat approached the spout and was terminated once the rat escaped into a white compartment. Subjects were then given intra-amygdala or hippocampal infusions of PBS or a dose of norepinephrine (0.2 μg) previously shown to enhance memory. Later, all subjects were given intra-accumbens infusion of muscimol to functionally inactivate the shell. Muscimol inactivation of the accumbens shell was delayed to allow sufficient time for norepinephrine to activate intracellular cascades that lead to long-term synaptic modifications

  5. Chronic stress enhanced fear memories are associated with increased amygdala zif268 mRNA expression and are resistant to reconsolidation.

    Science.gov (United States)

    Hoffman, Ann N; Parga, Alejandro; Paode, Pooja R; Watterson, Lucas R; Nikulina, Ella M; Hammer, Ronald P; Conrad, Cheryl D

    2015-04-01

    The chronically stressed brain may present a vulnerability to develop maladaptive fear-related behaviors in response to a traumatic event. In rodents, chronic stress leads to amygdala hyperresponsivity and dendritic hypertrophy and produces a post traumatic stress disorder (PTSD)-like phenotype that includes exaggerated fear learning following Pavlovian fear conditioning and resistance to extinction. It is unknown whether chronic stress-induced enhanced fear memories are vulnerable to disruption via reconsolidation blockade, as a novel therapeutic approach for attenuating exaggerated fear memories. We used a chronic stress procedure in a rat model (wire mesh restraint for 6h/d/21d) to create a vulnerable brain that leads to a PTSD-like phenotype. We then examined freezing behavior during acquisition, reactivation and after post-reactivation rapamycin administration (i.p., 40mg/kg) in a Pavlovian fear conditioning paradigm to determine its effects on reconsolidation as well as the subsequent functional activation of limbic structures using zif268 mRNA. Chronic stress increased amygdala zif268 mRNA during fear memory retrieval at reactivation. Moreover, these enhanced fear memories were unaffected by post reactivation rapamycin to disrupt long-term fear memory. Also, post-reactivation long term memory processing was also associated with increased amygdala (LA and BA), and decreased hippocampal CA1 zif268 mRNA expression. These results suggest potential challenges for reconsolidation blockade as an effective approach in treating exaggerated fear memories, as in PTSD. Our findings also support chronic stress manipulations combined with fear conditioning as a useful preclinical approach to study a PTSD-like phenotype. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Effects of normal aging and Alzheimer's disease on emotional memory.

    Science.gov (United States)

    Kensinger, Elizabeth A; Brierley, Barbara; Medford, Nick; Growdon, John H; Corkin, Suzanne

    2002-06-01

    Recall is typically better for emotional than for neutral stimuli. This enhancement is believed to rely on limbic regions. Memory is also better for neutral stimuli embedded in an emotional context. The neural substrate supporting this effect has not been thoroughly investigated but may include frontal lobe, as well as limbic circuits. Alzheimer's disease (AD) results in atrophy of limbic structures, whereas normal aging relatively spares limbic regions but affects prefrontal areas. The authors hypothesized that AD would reduce all enhancement effects, whereas aging would disproportionately affect enhancement based on emotional context. The results confirmed the authors' hypotheses: Young and older adults, but not AD patients, showed better memory for emotional versus neutral pictures and words. Older adults and AD patients showed no benefit from emotional context, whereas young adults remembered more items embedded in an emotional versus neutral context.

  7. Political conservatism predicts asymmetries in emotional scene memory.

    Science.gov (United States)

    Mills, Mark; Gonzalez, Frank J; Giuseffi, Karl; Sievert, Benjamin; Smith, Kevin B; Hibbing, John R; Dodd, Michael D

    2016-06-01

    Variation in political ideology has been linked to differences in attention to and processing of emotional stimuli, with stronger responses to negative versus positive stimuli (negativity bias) the more politically conservative one is. As memory is enhanced by attention, such findings predict that memory for negative versus positive stimuli should similarly be enhanced the more conservative one is. The present study tests this prediction by having participants study 120 positive, negative, and neutral scenes in preparation for a subsequent memory test. On the memory test, the same 120 scenes were presented along with 120 new scenes and participants were to respond whether a scene was old or new. Results on the memory test showed that negative scenes were more likely to be remembered than positive scenes, though, this was true only for political conservatives. That is, a larger negativity bias was found the more conservative one was. The effect was sizeable, explaining 45% of the variance across subjects in the effect of emotion. These findings demonstrate that the relationship between political ideology and asymmetries in emotion processing extend to memory and, furthermore, suggest that exploring the extent to which subject variation in interactions among emotion, attention, and memory is predicted by conservatism may provide new insights into theories of political ideology. Published by Elsevier B.V.

  8. Fact retrieval and memory consolidation for a movement sequence: bidirectional effects of 'unrelated' cognitive tasks on procedural memory.

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    Rachel Tibi

    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.

  9. Memory processing and the glucose facilitation effect: the effects of stimulus difficulty and memory load.

    Science.gov (United States)

    Meikle, Andrew; Riby, Leigh M; Stollery, Brian

    2005-08-01

    Previous research has consistently found enhancement of memory after the ingestion of a glucose containing drink. The aims of the present study were to specify more precisely the nature of this facilitation by examining the cognitive demand hypothesis. This hypothesis predicts greater glucose induced facilitation on tasks that require significant mental effort. In two experiments, both employing an unrelated sample design, participants consumed either 25 g of glucose or a control solution. In experiment 1, participants first studied low and high imagery word-pairs and memory was assessed 1-, 7- and 14-days later by cued recall. Overall, glucose enhanced both encoding and consolidation processes only for the more difficult low imagery pairs. In experiment 2, the degree of mental effort in a verbal memory task was manipulated in two ways: (1) by varying the phonological similarity of the words; and (2) by varying the length of word lists. Glucose was found to enhance memory only for longer word lists. These data are consistent with the idea that glucose is especially effective in demanding memory tasks, but place some limits on the forms of difficulty that are susceptible to enhancement.

  10. The neuroscience of positive memory deficits in depression

    Science.gov (United States)

    Dillon, Daniel G.

    2015-01-01

    Adults with unipolar depression typically show poor episodic memory for positive material, but the neuroscientific mechanisms responsible for this deficit have not been characterized. I suggest a simple hypothesis: weak memory for positive material in depression reflects disrupted communication between the mesolimbic dopamine pathway and medial temporal lobe (MTL) memory systems during encoding. This proposal draws on basic research showing that dopamine release in the hippocampus is critical for the transition from early- to late-phase long-term potentiation (LTP) that marks the conversion of labile, short-term memories into stable, long-term memories. Neuroimaging and pharmacological data from healthy humans paint a similar picture: activation of the mesolimbic reward circuit enhances encoding and boosts retention. Unipolar depression is characterized by anhedonia–loss of pleasure–and reward circuit dysfunction, which is believed to reflect negative effects of stress on the mesolimbic dopamine pathway. Thus, I propose that the MTL is deprived of strengthening reward signals in depressed adults and memory for positive events suffers accordingly. Although other mechanisms are important, this hypothesis holds promise as an explanation for positive memory deficits in depression. PMID:26441703

  11. The neuroscience of positive memory deficits in depression

    Directory of Open Access Journals (Sweden)

    Daniel Gerard Dillon

    2015-09-01

    Full Text Available Adults with unipolar depression typically show poor episodic memory for positive material, but the neuroscientific mechanisms responsible for this deficit have not been characterized. I suggest a simple hypothesis: weak memory for positive material in depression reflects disrupted communication between the mesolimbic dopamine pathway and medial temporal lobe (MTL memory systems during encoding. This proposal draws on basic research showing that dopamine release in the hippocampus is critical for the transition from early- to late-phase long-term potentiation (LTP that marks the conversion of labile, short-term memories into stable, long-term memories. Neuroimaging and pharmacological data from healthy humans paint a similar picture: activation of the mesolimbic reward circuit enhances encoding and boosts retention. Unipolar depression is characterized by anhedonia--loss of pleasure--and reward circuit dysfunction, which is believed to reflect negative effects of stress on the mesolimbic dopamine pathway. Thus, I propose that the MTL is deprived of strengthening reward signals in depressed adults and memory for positive events suffers accordingly. Although other mechanisms are important, this hypothesis holds promise as an explanation for positive memory deficits in depression.

  12. Does computerized working memory training with game elements enhance motivation and training efficacy in children with ADHD?

    NARCIS (Netherlands)

    Prins, P.J.M.; Dovis, S.; Ponsioen, A.; ten Brink, E.; van der Oord, S.

    2011-01-01

    This study examined the benefits of adding game elements to standard computerized working memory (WM) training. Specifically, it examined whether game elements would enhance motivation and training performance of children with ADHD, and whether it would improve training efficacy. A total of 51

  13. Music, memory and emotion.

    Science.gov (United States)

    Jäncke, Lutz

    2008-08-08

    Because emotions enhance memory processes and music evokes strong emotions, music could be involved in forming memories, either about pieces of music or about episodes and information associated with particular music. A recent study in BMC Neuroscience has given new insights into the role of emotion in musical memory.

  14. Pianists exhibit enhanced memory for vocal melodies but not piano melodies.

    Science.gov (United States)

    Weiss, Michael W; Vanzella, Patrícia; Schellenberg, E Glenn; Trehub, Sandra E

    2015-01-01

    Nonmusicians remember vocal melodies (i.e., sung to la la) better than instrumental melodies. If greater exposure to the voice contributes to those effects, then long-term experience with instrumental timbres should elicit instrument-specific advantages. Here we evaluate this hypothesis by comparing pianists with other musicians and nonmusicians. We also evaluate the possibility that absolute pitch (AP), which involves exceptional memory for isolated pitches, influences melodic memory. Participants heard 24 melodies played in four timbres (voice, piano, banjo, marimba) and were subsequently required to distinguish the melodies heard previously from 24 novel melodies presented in the same timbres. Musicians performed better than nonmusicians, but both groups showed a comparable memory advantage for vocal melodies. Moreover, pianists performed no better on melodies played on piano than on other instruments, and AP musicians performed no differently than non-AP musicians. The findings confirm the robust nature of the voice advantage and rule out explanations based on familiarity, practice, and motor representations.

  15. Functional neuroimaging studies of episodic memory. Functional dissociation in the medial temporal lobe structures

    International Nuclear Information System (INIS)

    Tsukiura, Takashi

    2008-01-01

    Previous functional neuroimaging studies have demonstrated the critical role of the medial temporal lobe (MTL) regions in the encoding and retrieval of episodic memory. It has also been shown that an emotional factor in human memory enhances episodic encoding and retrieval. However, there is little evidence regarding the specific contribution of each MTL region to the relational, contextual, and emotional processes of episodic memory. The goal of this review article is to identify differential activation patterns of the processes between MTL regions. Results from functional neuroimaging studies of episodic memory show that the hippocampus is involved in encoding the relation between memory items, whereas the entorhinal and perirhinal cortices (anterior parahippocampal gyrus) contribute to the encoding of a single item. Additionally, the parahippocampal cortex (posterior parahippocampal gyrus) is selectively activated during the processing of contextual information of episodic memory. A similar pattern of functional dissociation is found in episodic memory retrieval. Functional neuroimaging has also shown that emotional information of episodic memory enhances amygdala-MTL correlations and that this enhancement is observed during both the encoding and retrieval of emotional memories. These findings from pervious neuroimaging studies suggest that different MTL regions could organize memory for personally experienced episodes via the 'relation' and 'context' factors of episodic memory, and that the emotional factor of episodes could modulate the functional organization in the MTL regions. (author)

  16. Effect of yogic education system and modern education system on memory

    Directory of Open Access Journals (Sweden)

    Rangan R

    2009-01-01

    Full Text Available Background/Aim: Memory is more associated with the temporal cortex than other cortical areas. The two main components of memory are spatial and verbal which relate to right and left hemispheres of the brain, respectively. Many investigations have shown the beneficial effects of yoga on memory and temporal functions of the brain. This study was aimed at comparing the effect of one Gurukula Education System (GES school based on a yoga way of life with a school using the Modern Education System (MES on memory. Materials and Methods: Forty nine boys of ages ranging from 11-13 years were selected from each of two residential schools, one MES and the other GES, providing similar ambiance and daily routines. The boys were matched for age and socioeconomic status. The GES educational program is based around integrated yoga modules while the MES provides a conventional modern education program. Memory was assessed by means of standard spatial and verbal memory tests applicable to Indian conditions before and after an academic year. Results: Between groups there was matching at start of the academic year, while after it the GES boys showed significant enhancement in both verbal and visual memory scores than MES boys (P < 0.001, Mann-Whitney test. Conclusions: The present study showed that the GES meant for total personality development adopting yoga way of life is more effective in enhancing visual and verbal memory scores than the MES.

  17. Google Calendar Enhances Prospective Memory in Alzheimer's Disease: A Case Report.

    Science.gov (United States)

    El Haj, Mohamad; Gallouj, Karim; Antoine, Pascal

    2017-01-01

    We investigated whether an external memory aid (i.e., Google Calendar) would alleviate prospective memory compromise in a patient with mild Alzheimer's disease. The patient was asked in the baseline phase to perform three prospective targeted events (e.g., attending her weekly bridge game at the community club) and three prospective control events (e.g., buying her weekly magazine). The same six prospective events were assessed in the intervention phase but the targeted-events were cued by Google Calendar while the control-events were not. Results showed less omission of the targeted events in the training phase than in the baseline phase, suggesting a positive effect of Google Calendar. This case report offers a unique view into how smartphone calendars may alleviate prospective memory compromise in patients with mild Alzheimer's disease.

  18. Cholinergic Enhancement of Brain Activation in Mild Cognitive Impairment (MCI during Episodic Memory Encoding

    Directory of Open Access Journals (Sweden)

    Shannon L Risacher

    2013-09-01

    Full Text Available Objective: To determine the physiological impact of treatment with donepezil (Aricept on neural circuitry supporting episodic memory encoding in patients with amnestic mild cognitive impairment (MCI using functional MRI (fMRI. Methods: 18 patients with MCI and 20 age-matched healthy controls (HC were scanned twice while performing an event-related verbal episodic encoding task. MCI participants were scanned before treatment and after approximately 3 months on donepezil; HC were untreated but rescanned at the same interval. Voxel-level analyses assessed treatment effects in activation profile relative to retest changes in non-treated HC. Changes in task-related connectivity in medial temporal circuitry were also evaluated, as were associations between brain activation pattern, task-related functional connectivity, task performance, and clinical measures of cognition.Results: At baseline, the MCI group showed reduced activation during encoding relative to HC in the right medial temporal lobe (MTL; hippocampal/parahippocampal and additional regions, as well as attenuated task-related deactivation, relative to rest, in a medial parietal lobe cluster. After treatment, the MCI group showed normalized MTL activation and improved parietal deactivation. These changes were associated with cognitive performance. After treatment, the MCI group also demonstrated increased task-related functional connectivity from the right MTL cluster seed region to a network of other sites including the basal nucleus/caudate and bilateral frontal lobes. Increased functional connectivity was associated with improved task performance.Conclusions: Pharmacologic enhancement of cholinergic function in amnestic MCI is associated with changes in brain activation pattern and functional connectivity during episodic memory processing which are in turn related to increased cognitive performance. fMRI is a promising biomarker for assessing treatment related changes in brain function.

  19. Effect of quercetin on chronic enhancement of spatial learning and memory of mice

    Institute of Scientific and Technical Information of China (English)

    LIU; Jiancai; YU; Huqing

    2006-01-01

    In this study we evaluated the effect of quercetin on D-galactose-induced aged mice using the Morris water maze (MWM) test. Based on the free radical theory of aging, experiments were performed to study the possible biochemical mechanisms of glutathione (GSH) level and hydroxyl radical (OH-) in the hippocampus and cerebral cortex and the brain tissue enzyme activity of the mice. The results indicated that quercetin can enhance the exploratory behavior, spatial learning and memory of the mice. The effects relate with enhancing the brain functions and inhibiting oxidative stress by quercetin, and relate with increasing the GSH level and decreasing the OH- content. These findings suggest that quercetin can work as a possible natural anti-aging pharmaceutical product.

  20. Working memory training shows immediate and long-term effects on cognitive performance in children

    Science.gov (United States)

    Pugin, Fiona; Metz, Andreas J.; Stauffer, Madlaina; Wolf, Martin; Jenni, Oskar G.; Huber, Reto

    2014-01-01

    Working memory is important for mental reasoning and learning processes. Several studies in adults and school-age children have shown performance improvement in cognitive tests after working memory training. Our aim was to examine not only immediate but also long-term effects of intensive working memory training on cognitive performance tests in children. Fourteen healthy male subjects between 10 and 16 years trained a visuospatial n-back task over 3 weeks (30 min daily), while 15 individuals of the same age range served as a passive control group. Significant differences in immediate (after 3 weeks of training) and long-term effects (after 2-6 months) in an auditory n-back task were observed compared to controls (2.5 fold immediate and 4.7 fold long-term increase in the training group compared to the controls). The improvement was more pronounced in subjects who improved their performance during the training. Other cognitive functions (matrices test and Stroop task) did not change when comparing the training group to the control group. We conclude that visuospatial working memory training in children boosts performance in similar memory tasks such as the auditory n-back task. The sustained performance improvement several months after the training supports the effectiveness of the training. PMID:25671082

  1. On recency and echoic memory.

    Science.gov (United States)

    Gardiner, J M

    1983-08-11

    In short-term memory, the tendency for the last few (recency) items from a verbal sequence to be increasingly well recalled is more pronounced if the items are spoken rather than written. This auditory recency advantage has been quite generally attributed to echoic memory, on the grounds that in the auditory, but not the visual, mode, sensory memory persists just long enough to supplement recall of the most recent items. This view no longer seems tenable. There are now several studies showing that an auditory recency advantage occurs not only in long-term memory, but under conditions in which it cannot possibly be attributed to echoic memory. Also, similar recency phenomena have been discovered in short-term memory when the items are lip-read, or presented in sign-language, rather than heard. This article provides a partial review of these studies, taking a broad theoretical position from which these particular recency phenomena are approached as possible exceptions, to a general theory according to which recency is due to temporal distinctiveness. Much of the fresh evidence reviewed is of a somewhat preliminary nature and it is as yet unexplained by any theory of memory. The need for additional, converging experimental tests is obvious; so too is the need for further theoretical development. Several alternative theoretical resolutions are mentioned, including the possibility that enhanced recency may reflect movement, from sequentially occurring stimulus features, and the suggestion that it may be associated with the primary linguistic mode of the individuals concerned. But special weight is attached to the conjecture that all these recency phenomena might be accounted for in terms of distinctiveness or discriminability. On this view, the enhanced recency effects observed with certain modes, including the auditory mode, are attributed to items possessing greater temporal discriminability in those modes.

  2. Extinction partially reverts structural changes associated with remote fear memory

    DEFF Research Database (Denmark)

    Vetere, Gisella; Restivo, Leonardo; Novembre, Giovanni

    2011-01-01

    Structural synaptic changes occur in medial prefrontal cortex circuits during remote memory formation. Whether extinction reverts or further reshapes these circuits is, however, unknown. Here we show that the number and the size of spines were enhanced in anterior cingulate (aCC) and infralimbic...... the remote memory network, suggesting that the preserved network properties might sustain reactivation of extinguished conditioned fear....

  3. Music, memory and emotion

    Science.gov (United States)

    Jäncke, Lutz

    2008-01-01

    Because emotions enhance memory processes and music evokes strong emotions, music could be involved in forming memories, either about pieces of music or about episodes and information associated with particular music. A recent study in BMC Neuroscience has given new insights into the role of emotion in musical memory. PMID:18710596

  4. Motivation matters: differing effects of pre-goal and post-goal emotions on attention and memory.

    Science.gov (United States)

    Kaplan, Robin L; Van Damme, Ilse; Levine, Linda J

    2012-01-01

    People often show enhanced memory for information that is central to emotional events and impaired memory for peripheral details. The intensity of arousal elicited by an emotional event is commonly held to be the mechanism underlying memory narrowing, with the implication that all sources of emotional arousal should have comparable effects. Discrete emotions differ in their effects on memory, however, with some emotions broadening rather than narrowing the range of information attended to and remembered. Thus, features of emotion other than arousal appear to play a critical role in memory narrowing. We review theory and research on emotional memory narrowing and argue that motivation matters. Recent evidence suggests that emotions experienced prior to goal attainment or loss lead to memory narrowing whereas emotions experienced after goal attainment or loss broaden the range of information encoded in memory. The motivational component of emotion is an important but understudied feature that can help to clarify the conditions under which emotions enhance and impair attention and memory.

  5. Motivation Matters: Differing Effects of Pre-goal and Post-goal Emotions on Attention and Memory

    Directory of Open Access Journals (Sweden)

    Robin L. Kaplan

    2012-10-01

    Full Text Available People often show enhanced memory for information that is central to emotional events and impaired memory for peripheral details. The intensity of arousal elicited by an emotional event is commonly held to be the mechanism underlying memory narrowing, with the implication that all sources of emotional arousal should have comparable effects. Discrete emotions differ in their effects on memory, however, with some emotions broadening rather than narrowing the range of information attended to and remembered. Thus, features of emotion other than arousal appear to play a critical role in memory narrowing. We review theory and research on emotional memory narrowing and argue that motivation matters. Recent evidence suggests that emotions experienced prior to goal attainment or loss lead to memory narrowing whereas emotions experienced after goal attainment or loss broaden the range of information encoded in memory. The motivational component of emotion is an important but understudied feature that can help to clarify the conditions under which emotions enhance and impair attention and memory.

  6. The Scaffolding Protein Synapse-Associated Protein 97 is Required for Enhanced Signaling Through Isotype-Switched IgG Memory B Cell Receptors

    Science.gov (United States)

    Liu, Wanli; Chen, Elizabeth; Zhao, Xing Wang; Wan, Zheng Peng; Gao, Yi Ren; Davey, Angel; Huang, Eric; Zhang, Lijia; Crocetti, Jillian; Sandoval, Gabriel; Joyce, M. Gordon; Miceli, Carrie; Lukszo, Jan; Aravind, L.; Swat, Wojciech; Brzostowski, Joseph; Pierce, Susan K.

    2012-01-01

    Memory B cells are generated during an individual's first encounter with a foreign antigen and respond to re-encounter with the same antigen through cell surface immunoglobulin G (IgG) B cell receptors (BCRs) resulting in rapid, high-titered IgG antibody responses. Despite a central role for IgG BCRs in B cell memory, our understanding of the molecular mechanism by which IgG BCRs enhance antibody responses is incomplete. Here, we showed that the conserved cytoplasmic tail of the IgG BCR, which contains a putative PDZ-binding motif, associated with synapse-associated protein 97 (SAP97), a member of the PDZ domain–containing, membrane-associated guanylate-kinase family of scaffolding molecules that play key roles in controlling receptor density and signal strength at neuronal synapses. We showed that SAP97 accumulated and bound to IgG BCRs in the immune synapses that formed in response to engagement of the B cell with antigen. Knocking down SAP97 in IgG-expressing B cells or mutating the putative PDZ-binding motif in the tail impaired immune synapse formation, the initiation of IgG BCR signaling, and downstream activation of p38 mitogen-activated protein kinase. Thus, heightened B cell memory responses are encoded, in part, by a mechanism that involves SAP97 serving as a scaffolding protein in the IgG BCR immune synapse. PMID:22855505

  7. Chronic caffeine consumption prevents memory disturbance in different animal models of memory decline.

    Science.gov (United States)

    Cunha, Rodrigo A; Agostinho, Paula M

    2010-01-01

    Caffeine, the most widely consumed psychoactive drug, enhances attention/vigilance, stabilizes mood, and might also independently enhance cognitive performance. Notably, caffeine displays clearer and more robust beneficial effects on memory performance when memory is perturbed by stressful or noxious stimuli either in human or animal studies. Thus, caffeine restores memory performance in sleep-deprived or aged human individuals, a finding replicated in rodent animal models. Likewise, in animal models of Alzheimer's disease (AD), caffeine alleviates memory dysfunction, which is in accordance with the tentative inverse correlation between caffeine intake and the incidence of AD in different (but not all) cohorts. Caffeine also affords beneficial effects in animal models of conditions expected to impair memory performance such as Parkinson's disease, chronic stress, type 2 diabetes, attention deficit and hyperactivity disorder, early life convulsions, or alcohol-induced amnesia. Thus, caffeine should not be viewed as a cognitive enhancer but instead as a cognitive normalizer. Interestingly, these beneficial effects of caffeine on stress-induced memory disturbance are mimicked by antagonists of adenosine A2A receptors. This prominent role of A2A receptors in preventing memory deterioration is probably related to the synaptic localization of this receptor in limbic areas and its ability to control glutamatergic transmission, especially NMDA receptor-dependent plasticity, and to control apoptosis, brain metabolism, and the burden of neuroinflammation. This opens the real and exciting possibility that caffeine consumption might be a prophylactic strategy and A2A receptor antagonists may be a novel therapeutic option to manage memory dysfunction both in AD and in other chronic neurodegenerative disorders where memory deficits occur.

  8. High-throughput olfactory conditioning and memory retention test show variation in Nasonia parasitic wasps.

    NARCIS (Netherlands)

    Hoedjes, K.M.; Steidle, J.L.M.; Werren, J.H.; Vet, L.E.M.; Smid, H.M.

    2012-01-01

    Most of our knowledge on learning and memory formation results from extensive studies on a small number of animal species. Although features and cellular pathways of learning and memory are highly similar in this diverse group of species, there are also subtle differences. Closely related species of

  9. Dynamics of auditory working memory

    Directory of Open Access Journals (Sweden)

    Jochen eKaiser

    2015-05-01

    Full Text Available Working memory denotes the ability to retain stimuli in mind that are no longer physically present and to perform mental operations on them. Electro- and magnetoencephalography allow investigating the short-term maintenance of acoustic stimuli at a high temporal resolution. Studies investigating working memory for non-spatial and spatial auditory information have suggested differential roles of regions along the putative auditory ventral and dorsal streams, respectively, in the processing of the different sound properties. Analyses of event-related potentials have shown sustained, memory load-dependent deflections over the retention periods. The topography of these waves suggested an involvement of modality-specific sensory storage regions. Spectral analysis has yielded information about the temporal dynamics of auditory working memory processing of individual stimuli, showing activation peaks during the delay phase whose timing was related to task performance. Coherence at different frequencies was enhanced between frontal and sensory cortex. In summary, auditory working memory seems to rely on the dynamic interplay between frontal executive systems and sensory representation regions.

  10. An Agent-Based Model for the Role of Short-Term Memory Enhancement in the Emergence of Grammatical Agreement.

    Science.gov (United States)

    Vera, Javier

    2018-01-01

    What is the influence of short-term memory enhancement on the emergence of grammatical agreement systems in multi-agent language games? Agreement systems suppose that at least two words share some features with each other, such as gender, number, or case. Previous work, within the multi-agent language-game framework, has recently proposed models stressing the hypothesis that the emergence of a grammatical agreement system arises from the minimization of semantic ambiguity. On the other hand, neurobiological evidence argues for the hypothesis that language evolution has mainly related to an increasing of short-term memory capacity, which has allowed the online manipulation of words and meanings participating particularly in grammatical agreement systems. Here, the main aim is to propose a multi-agent language game for the emergence of a grammatical agreement system, under measurable long-range relations depending on the short-term memory capacity. Computer simulations, based on a parameter that measures the amount of short-term memory capacity, suggest that agreement marker systems arise in a population of agents equipped at least with a critical short-term memory capacity.

  11. Targeted memory reactivation during slow wave sleep facilitates emotional memory consolidation.

    Science.gov (United States)

    Cairney, Scott A; Durrant, Simon J; Hulleman, Johan; Lewis, Penelope A

    2014-04-01

    To investigate the mechanisms by which auditory targeted memory reactivation (TMR) during slow wave sleep (SWS) influences the consolidation of emotionally negative and neutral memories. Each of 72 (36 negative, 36 neutral) picture-location associations were encoded with a semantically related sound. During a subsequent nap, half of the sounds were replayed in SWS, before picture-location recall was examined in a final test. Manchester Sleep Laboratory, University of Manchester. 15 adults (3 male) mean age = 20.40 (standard deviation ± 3.07). TMR with auditory cues during SWS. Performance was assessed by memory accuracy and recall response times (RTs). Data were analyzed with a 2 (sound: replayed/not replayed) × 2 (emotion: negative/neutral) repeated measures analysis of covariance with SWS duration, and then SWS spindles, as the mean-centered covariate. Both analyses revealed a significant three-way interaction for RTs but not memory accuracy. Critically, SWS duration and SWS spindles predicted faster memory judgments for negative, relative to neutral, picture locations that were cued with TMR. TMR initiates an enhanced consolidation process during subsequent SWS, wherein sleep spindles mediate the selective enhancement of reactivated emotional memories.

  12. Learning and memory in conditioned fear extinction: effects of d-cycloserine

    NARCIS (Netherlands)

    Vervliet, B.

    2008-01-01

    This review addresses the effects of the cognitive enhancer D-cycloserine (DCS) on the memory processes that occur in conditioned fear extinction, which is the experimental model for exposure techniques to reduce clinical anxiety. All reported rat studies show an enhanced fear extinction effect when

  13. Noradrenergic Activation of the Basolateral Amygdala Enhances Object Recognition Memory and Induces Chromatin Remodeling in the Insular Cortex

    Directory of Open Access Journals (Sweden)

    Hassiba eBeldjoud

    2015-04-01

    Full Text Available It is well established that arousal-induced memory enhancement requires noradrenergic activation of the basolateral complex of the amygdala (BLA and modulatory influences on information storage processes in its many target regions. While this concept is well accepted, the molecular basis of such BLA effects on neural plasticity changes within other brain regions remains to be elucidated. The present study investigated whether noradrenergic activation of the BLA after object recognition training induces chromatin remodeling through histone post-translational modifications in the insular cortex (IC, a brain region that is importantly involved in object recognition memory. Male Sprague–Dawley rats were trained on an object recognition task, followed immediately by bilateral microinfusions of norepinephrine (1.0 µg or saline administered into the BLA. Saline-treated control rats exhibited poor 24-h retention, whereas norepinephrine treatment induced robust 24-h object recognition memory. Most importantly, this memory-enhancing dose of norepinephrine induced a global reduction in the acetylation levels of histone H3 at lysine 14, H2B and H4 in the IC 1 h later, whereas it had no effect on the phosphorylation of histone H3 at serine 10 or tri-methylation of histone H3 at lysine 27. Norepinephrine administered into the BLA of non-trained control rats did not induce any changes in the histone marks investigated in this study. These findings indicate that noradrenergic activation of the BLA induces training-specific effects on chromatin remodeling mechanisms, and presumably gene transcription, in its target regions, which may contribute to the understanding of the molecular mechanisms of stress and emotional arousal effects on memory consolidation.

  14. Sarcosine attenuates toluene-induced motor incoordination, memory impairment, and hypothermia but not brain stimulation reward enhancement in mice

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Ming-Huan [Department of Pharmacology and Toxicology, Tzu Chi University, Hualien, Taiwan (China); Institute of Neuroscience, National Changchi University, Taipei, Taiwan (China); Chung, Shiang-Sheng [Department of Pharmacology and Toxicology, Tzu Chi University, Hualien, Taiwan (China); Department of Pharmacy, Yuli Veterans Hospital, Hualien, Taiwan (China); Stoker, Astrid K.; Markou, Athina [Department of Psychiatry, School of Medicine, University of California San Diego, La Jolla, CA (United States); Chen, Hwei-Hsien, E-mail: hwei@nhri.org.tw [Department of Pharmacology and Toxicology, Tzu Chi University, Hualien, Taiwan (China); Division of Mental Health and Addiction Medicine, Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Miaoli County, Taiwan (China)

    2012-12-01

    Toluene, a widely used and commonly abused organic solvent, produces various behavioral disturbances, including motor incoordination and cognitive impairment. Toluene alters the function of a large number of receptors and ion channels. Blockade of N-methyl-D-aspartate (NMDA) receptors has been suggested to play a critical role in toluene-induced behavioral manifestations. The present study determined the effects of various toluene doses on motor coordination, recognition memory, body temperature, and intracranial self-stimulation (ICSS) thresholds in mice. Additionally, the effects of sarcosine on the behavioral and physiological effects induced by toluene were evaluated. Sarcosine may reverse toluene-induced behavioral manifestations by acting as an NMDA receptor co-agonist and by inhibiting the effects of the type I glycine transporter (GlyT1). Mice were treated with toluene alone or combined with sarcosine pretreatment and assessed for rotarod performance, object recognition memory, rectal temperature, and ICSS thresholds. Toluene dose-dependently induced motor incoordination, recognition memory impairment, and hypothermia and lowered ICSS thresholds. Sarcosine pretreatment reversed toluene-induced changes in rotarod performance, novel object recognition, and rectal temperature but not ICSS thresholds. These findings suggest that the sarcosine-induced potentiation of NMDA receptors may reverse motor incoordination, memory impairment, and hypothermia but not the enhancement of brain stimulation reward function associated with toluene exposure. Sarcosine may be a promising compound to prevent acute toluene intoxications by occupational or intentional exposure. -- Highlights: ► Toluene induces impairments in Rotarod test and novel object recognition test. ► Toluene lowers rectal temperature and ICSS thresholds in mice. ► Sarcosine reverses toluene-induced changes in motor, memory and body temperature. ► Sarcosine pretreatment does not affect toluene

  15. Sarcosine attenuates toluene-induced motor incoordination, memory impairment, and hypothermia but not brain stimulation reward enhancement in mice

    International Nuclear Information System (INIS)

    Chan, Ming-Huan; Chung, Shiang-Sheng; Stoker, Astrid K.; Markou, Athina; Chen, Hwei-Hsien

    2012-01-01

    Toluene, a widely used and commonly abused organic solvent, produces various behavioral disturbances, including motor incoordination and cognitive impairment. Toluene alters the function of a large number of receptors and ion channels. Blockade of N-methyl-D-aspartate (NMDA) receptors has been suggested to play a critical role in toluene-induced behavioral manifestations. The present study determined the effects of various toluene doses on motor coordination, recognition memory, body temperature, and intracranial self-stimulation (ICSS) thresholds in mice. Additionally, the effects of sarcosine on the behavioral and physiological effects induced by toluene were evaluated. Sarcosine may reverse toluene-induced behavioral manifestations by acting as an NMDA receptor co-agonist and by inhibiting the effects of the type I glycine transporter (GlyT1). Mice were treated with toluene alone or combined with sarcosine pretreatment and assessed for rotarod performance, object recognition memory, rectal temperature, and ICSS thresholds. Toluene dose-dependently induced motor incoordination, recognition memory impairment, and hypothermia and lowered ICSS thresholds. Sarcosine pretreatment reversed toluene-induced changes in rotarod performance, novel object recognition, and rectal temperature but not ICSS thresholds. These findings suggest that the sarcosine-induced potentiation of NMDA receptors may reverse motor incoordination, memory impairment, and hypothermia but not the enhancement of brain stimulation reward function associated with toluene exposure. Sarcosine may be a promising compound to prevent acute toluene intoxications by occupational or intentional exposure. -- Highlights: ► Toluene induces impairments in Rotarod test and novel object recognition test. ► Toluene lowers rectal temperature and ICSS thresholds in mice. ► Sarcosine reverses toluene-induced changes in motor, memory and body temperature. ► Sarcosine pretreatment does not affect toluene

  16. Working Memory Enhances Visual Perception: Evidence from Signal Detection Analysis

    Science.gov (United States)

    Soto, David; Wriglesworth, Alice; Bahrami-Balani, Alex; Humphreys, Glyn W.

    2010-01-01

    We show that perceptual sensitivity to visual stimuli can be modulated by matches between the contents of working memory (WM) and stimuli in the visual field. Observers were presented with an object cue (to hold in WM or to merely attend) and subsequently had to identify a brief target presented within a colored shape. The cue could be…

  17. Semantic congruence enhances memory of episodic associations: role of theta oscillations.

    Science.gov (United States)

    Atienza, Mercedes; Crespo-Garcia, Maite; Cantero, Jose L

    2011-01-01

    Growing evidence suggests that theta oscillations play a crucial role in episodic encoding. The present study evaluates whether changes in electroencephalographic theta source dynamics mediate the positive influence of semantic congruence on incidental associative learning. Here we show that memory for episodic associations (face-location) is more accurate when studied under semantically congruent contexts. However, only participants showing RT priming effect in a conceptual priming test (priming group) also gave faster responses when recollecting source information of semantically congruent faces as compared with semantically incongruent faces. This improved episodic retrieval was positively correlated with increases in theta power during the study phase mainly in the bilateral parahippocampal gyrus, left superior temporal gyrus, and left lateral posterior parietal lobe. Reconstructed signals from the estimated sources showed higher theta power for congruent than incongruent faces and also for the priming than the nonpriming group. These results are in agreement with the attention to memory model. Besides directing top-down attention to goal-relevant semantic information during encoding, the dorsal parietal lobe may also be involved in redirecting attention to bottom-up-driven memories thanks to connections between the medial-temporal and the left ventral parietal lobe. The latter function can either facilitate or interfere with encoding of face-location associations depending on whether they are preceded by semantically congruent or incongruent contexts, respectively, because only in the former condition retrieved representations related to the cue and the face are both coherent with the person identity and are both associated with the same location.

  18. Memory for Emotional Pictures in Patients with Alzheimer's Dementia: Comparing Picture-Location Binding and Subsequent Recognition

    Directory of Open Access Journals (Sweden)

    Marloes J. Huijbers

    2011-01-01

    Full Text Available Emotional content typically facilitates subsequent memory, known as the emotional enhancement effect. We investigated whether emotional content facilitates spatial and item memory in patients with Alzheimer's dementia (AD. Twenty-three AD patients, twenty-three healthy elderly, and twenty-three young adults performed a picture relocation task and a delayed recognition task with positive, negative, and neutral stimuli. AD patients showed a benefit in immediate spatial memory for positive pictures, while healthy young and older participants did not benefit from emotional content. No emotional enhancement effects on delayed item recognition were seen. We conclude that AD patients may have a memory bias for positive information in spatial memory. Discrepancies between our findings and earlier studies are discussed.

  19. Lactate produced by glycogenolysis in astrocytes regulates memory processing.

    Science.gov (United States)

    Newman, Lori A; Korol, Donna L; Gold, Paul E

    2011-01-01

    When administered either systemically or centrally, glucose is a potent enhancer of memory processes. Measures of glucose levels in extracellular fluid in the rat hippocampus during memory tests reveal that these levels are dynamic, decreasing in response to memory tasks and loads; exogenous glucose blocks these decreases and enhances memory. The present experiments test the hypothesis that glucose enhancement of memory is mediated by glycogen storage and then metabolism to lactate in astrocytes, which provide lactate to neurons as an energy substrate. Sensitive bioprobes were used to measure brain glucose and lactate levels in 1-sec samples. Extracellular glucose decreased and lactate increased while rats performed a spatial working memory task. Intrahippocampal infusions of lactate enhanced memory in this task. In addition, pharmacological inhibition of astrocytic glycogenolysis impaired memory and this impairment was reversed by administration of lactate or glucose, both of which can provide lactate to neurons in the absence of glycogenolysis. Pharmacological block of the monocarboxylate transporter responsible for lactate uptake into neurons also impaired memory and this impairment was not reversed by either glucose or lactate. These findings support the view that astrocytes regulate memory formation by controlling the provision of lactate to support neuronal functions.

  20. Human area MT+ shows load-dependent activation during working memory maintenance with continuously morphing stimulation.

    Science.gov (United States)

    Galashan, Daniela; Fehr, Thorsten; Kreiter, Andreas K; Herrmann, Manfred

    2014-07-11

    Initially, human area MT+ was considered a visual area solely processing motion information but further research has shown that it is also involved in various different cognitive operations, such as working memory tasks requiring motion-related information to be maintained or cognitive tasks with implied or expected motion.In the present fMRI study in humans, we focused on MT+ modulation during working memory maintenance using a dynamic shape-tracking working memory task with no motion-related working memory content. Working memory load was systematically varied using complex and simple stimulus material and parametrically increasing retention periods. Activation patterns for the difference between retention of complex and simple memorized stimuli were examined in order to preclude that the reported effects are caused by differences in retrieval. Conjunction analysis over all delay durations for the maintenance of complex versus simple stimuli demonstrated a wide-spread activation pattern. Percent signal change (PSC) in area MT+ revealed a pattern with higher values for the maintenance of complex shapes compared to the retention of a simple circle and with higher values for increasing delay durations. The present data extend previous knowledge by demonstrating that visual area MT+ presents a brain activity pattern usually found in brain regions that are actively involved in working memory maintenance.

  1. Effects on interpersonal memory of dancing in time with others

    Directory of Open Access Journals (Sweden)

    Matthew Harold Woolhouse

    2016-02-01

    Full Text Available We report an experiment investigating whether dancing to the same music enhances recall of person-related memory targets. The experiment used 40 dancers (all of whom were unaware of the experiment’s aim, 2-channel silent-disco radio headphones, a marked-up dance floor, two types of music, and memory targets (sash colours and symbols. In each trial, 10 dancers wore radio headphones and one of 4 different coloured sashes, half of which carried cat symbols. Using silent-disco technology, one type of music was surreptitiously transmitted to half the dancers, while music at a different tempo was transmitted to the remaining dancers. Pre-experiment, the dancers’ faces were photographed. Post-experiment, each dancer was presented with the photographs of the other dancers and asked to recall their memory targets. Results showed that same-music dancing significantly enhanced memory for sash colour and sash symbol. Our findings are discussed in light of recent eye-movement research that showed significantly increased gaze durations for people observing music-dance synchrony versus music-dance asynchrony, and in relation to current literature on interpersonal entrainment, group cohesion and social bonding.

  2. A calpain-2 selective inhibitor enhances learning & memory by prolonging ERK activation.

    Science.gov (United States)

    Liu, Yan; Wang, Yubin; Zhu, Guoqi; Sun, Jiandong; Bi, Xiaoning; Baudry, Michel

    2016-06-01

    While calpain-1 activation is required for LTP induction by theta burst stimulation (TBS), calpain-2 activation limits its magnitude during the consolidation period. A selective calpain-2 inhibitor applied either before or shortly after TBS enhanced the degree of potentiation. In the present study, we tested whether the selective calpain-2 inhibitor, Z-Leu-Abu-CONH-CH2-C6H3 (3, 5-(OMe)2 (C2I), could enhance learning and memory in wild-type (WT) and calpain-1 knock-out (C1KO) mice. We first showed that C2I could reestablish TBS-LTP in hippocampal slices from C1KO mice, and this effect was blocked by PD98059, an inhibitor of ERK. TBS resulted in PTEN degradation in hippocampal slices from both WT and C1KO mice, and C2I treatment blocked this effect in both mouse genotypes. Systemic injection of C2I 30 min before training in the fear-conditioning paradigm resulted in a biphasic dose-response curve, with low doses enhancing and high doses inhibiting freezing behavior. The difference between the doses needed to enhance and inhibit learning matches the difference in concentrations producing inhibition of calpain-2 and calpain-1. A low dose of C2I also restored normal learning in a novel object recognition task in C1KO mice. Levels of SCOP, a ERK phosphatase known to be cleaved by calpain-1, were decreased in dorsal hippocampus early but not late following training in WT mice; C2I treatment did not affect the early decrease in SCOP levels but prevented its recovery at the later time-point and prolonged ERK activation. The results indicate that calpain-2 activation limits the extent of learning, an effect possibly due to temporal limitation of ERK activation, as a result of SCOP synthesis induced by calpain-2-mediated PTEN degradation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Modulation of fusiform cortex activity by cholinesterase inhibition predicts effects on subsequent memory.

    Science.gov (United States)

    Bentley, P; Driver, J; Dolan, R J

    2009-09-01

    Cholinergic influences on memory are likely to be expressed at several processing stages, including via well-recognized effects of acetylcholine on stimulus processing during encoding. Since previous studies have shown that cholinesterase inhibition enhances visual extrastriate cortex activity during stimulus encoding, especially under attention-demanding tasks, we tested whether this effect correlates with improved subsequent memory. In a within-subject physostigmine versus placebo design, we measured brain activity with functional magnetic resonance imaging while healthy and mild Alzheimer's disease subjects performed superficial and deep encoding tasks on face (and building) visual stimuli. We explored regions in which physostigmine modulation of face-selective neural responses correlated with physostigmine effects on subsequent recognition performance. In healthy subjects physostigmine led to enhanced later recognition for deep- versus superficially-encoded faces, which correlated across subjects with a physostigmine-induced enhancement of face-selective responses in right fusiform cortex during deep- versus superficial-encoding tasks. In contrast, the Alzheimer's disease group showed neither a depth of processing effect nor restoration of this with physostigmine. Instead, patients showed a task-independent improvement in confident memory with physostigmine, an effect that correlated with enhancements in face-selective (but task-independent) responses in bilateral fusiform cortices. Our results indicate that one mechanism by which cholinesterase inhibitors can improve memory is by enhancing extrastriate cortex stimulus selectivity at encoding, in a manner that for healthy people but not in Alzheimer's disease is dependent upon depth of processing.

  4. The impact of aging and Alzheimer's disease on emotional enhancement of memory.

    Science.gov (United States)

    Baran, Zeynel; Cangöz, Banu; Ozel-Kizil, Erguvan T

    2014-01-01

    Emotional enhancement of memory (EEM) has been a well-known phenomenon which corresponds to the advantage of emotional stimuli to be better recalled than neutral ones. Previous studies suggest that aging favours recollection of positive items and this pattern is disrupted in Alzheimer's disease (AD). Emotional valence of different stimulus modalities, i.e. pictures and words, may also have an effect on each other's memory performances. However, none of these were clearly studied in AD. This study aimed to evaluate how emotional valences of simultaneously presented stimuli affected recall in healthy young (YG, n = 30), healthy elderly (HE, n = 30) participants and in patients with AD (n = 30). A battery consisting of emotional words presented on emotional pictures was developed. An analysis of a 3 (Groups) × 3 (Emotional Valence of Picture) × 3 (Emotional Valence of Word) mixed ANOVA design was carried out. Patients with AD could process emotional information similarly to healthy participants; however, they had EEM only for picture recalling. Emotional valence of the co-presented stimulus had a boosting effect both in the YG and HE, but not in AD group, especially if both of the stimuli had the same emotional valence. This study highlights the impaired EEM for verbal and preserved EEM for non-verbal declarative memory in patients with AD, the neurobiological underpinnings of which should be addressed by future studies. © 2014 S. Karger AG, Basel.

  5. Collaboration can improve individual recognition memory: evidence from immediate and delayed tests.

    Science.gov (United States)

    Rajaram, Suparna; Pereira-Pasarin, Luciane P

    2007-02-01

    In two experiments, we tested the effects of collaboration on individual recognition memory. In Experiment 1, participants studied pictures and words either for meaning or for surface properties and made recognition memory judgments individually either following group discussion among 3 members (collaborative condition) or in the absence of discussion (noncollaborative condition). Levels of processing and picture superiority effects were replicated, and collaboration significantly increased individual recognition memory. Experiment 2 replicated this positive effect and showed that even though memory sensitivity declined at longer delays (48 h and 1 week), collaboration continued to exert a positive influence. These findings show that (1) consensus is not necessary for producing benefits of collaboration on individual recognition, (2) collaborative facilitation on individual memory is robust, and (3) collaboration enhances individual memory further if conditions predispose individual accuracy in the absence of collaboration.

  6. Nigella sativa Oil Enhances the Spatial Working Memory Performance of Rats on a Radial Arm Maze.

    Science.gov (United States)

    Sahak, Mohamad Khairul Azali; Mohamed, Abdul Majid; Hashim, Noor Hashida; Hasan Adli, Durriyyah Sharifah

    2013-01-01

    Nigella sativa, an established historical and religion-based remedy for a wide range of health problems, is a herbal medicine known to have antioxidant and neuroprotective effects. This present study investigated the effect of Nigella sativa oil (NSO) administration on the spatial memory performance (SMP) of male adult rats using eight-arm radial arm maze (RAM). Twelve Sprague Dawley rats (7-9 weeks old) were force-fed daily with 6.0  μ L/100 g body weight of Nigella sativa oil (NSO group; n = 6) or 0.1 mL/100 g body weight of corn oil (control) (CO group; n = 6) for a period of 20 consecutive weeks. For each weekly evaluation of SMP, one day food-deprived rats were tested by allowing each of them 3 minutes to explore the RAM for food as their rewards. Similar to the control group, the SMP of the treated group was not hindered, as indicated by the establishment of the reference and working memory components of the spatial memory. The results demonstrated that lesser mean numbers of error were observed for the NSO-treated group in both parameters as compared to the CO-treated group. NSO could therefore enhance the learning and memory abilities of the rats; there was a significant decrease in the overall mean number of working memory error (WME) in the NSO-treated group.

  7. Caffeine suppresses exercise-enhanced long-term and location memory in middle-aged rats: Involvement of hippocampal Akt and CREB signaling.

    Science.gov (United States)

    Cechella, José L; Leite, Marlon R; da Rocha, Juliana T; Dobrachinski, Fernando; Gai, Bibiana M; Soares, Félix A A; Bresciani, Guilherme; Royes, Luiz F F; Zeni, Gilson

    2014-11-05

    The cognitive function decline is closely related with brain changes generated by age. The ability of caffeine and exercise to prevent memory impairment has been reported in animal models and humans. The purpose of the present study was to investigate whether swimming exercise and caffeine administration enhance memory in middle-aged Wistar rats. Male Wistar rats (18months) received caffeine at a dose of 30mg/kg, 5days per week by a period of 4weeks. Animals were subjected to swimming training with a workload (3% of body weight, 20min per day for 4weeks). After 4weeks, the object recognition test (ORT) and the object location test (OLT) were performed. The results of this study demonstrated that caffeine suppressed exercise-enhanced long-term (ORT) and spatial (OLT) memory in middle-aged and this effect may be related to a decrease in hippocampal p-CREB signaling. This study also provided evidence that the effects of this protocol on memory were not accompanied by alterations in the levels of activated Akt. The [(3)H] glutamate uptake was reduced in hippocampus of rats administered with caffeine and submitted to swimming protocol. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  8. Where to start? Bottom-up attention improves working memory by determining encoding order.

    Science.gov (United States)

    Ravizza, Susan M; Uitvlugt, Mitchell G; Hazeltine, Eliot

    2016-12-01

    The present study aimed to characterize the mechanism by which working memory is enhanced for items that capture attention because of their novelty or saliency-that is, via bottom-up attention. The first experiment replicated previous research by corroborating that bottom-up attention directed to an item is sufficient for enhancing working memory and, moreover, generalized the effect to the domain of verbal working memory. The subsequent 3 experiments sought to determine how bottom-up attention affects working memory. We considered 2 hypotheses: (1) Bottom-up attention enhances the encoded representation of the stimulus, similar to how voluntary attention functions, or (2) It affects the order of encoding by shifting priority onto the attended stimulus. By manipulating how stimuli were presented (simultaneous/sequential display) and whether the cue predicted the tested items, we found evidence that bottom-up attention improves working memory performance via the order of encoding hypothesis. This finding was observed across change detection and free recall paradigms. In contrast, voluntary attention improved working memory regardless of encoding order and showed greater effects on working memory. We conclude that when multiple information sources compete, bottom-up attention prioritizes the location at which encoding should begin. When encoding order is set, bottom-up attention has little or no benefit to working memory. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  9. On the Susceptibility of Adaptive Memory to False Memory Illusions

    Science.gov (United States)

    Howe, Mark L.; Derbish, Mary H.

    2010-01-01

    Previous research has shown that survival-related processing of word lists enhances retention for that material. However, the claim that survival-related memories are more accurate has only been examined when true recall and recognition of neutral material has been measured. In the current experiments, we examined the adaptive memory superiority…

  10. Regular rehearsal helps in consolidation of long term memory.

    Science.gov (United States)

    Parle, Milind; Singh, Nirmal; Vasudevan, Mani

    2006-01-01

    Memory, one of the most complex functions of the brain comprises of multiple components such as perception, registration, consolidation, storage, retrieval and decay. The present study was undertaken to evaluate the impact of different training sessions on the retention capacity of rats. The capacity of retention of learnt task was measured using exteroceptive behavioral models such as Hexagonal swimming pool apparatus, Hebb-Williams maze and Elevated plus-maze. A total of 150 rats divided into fifteen groups were employed in the present study. The animals were subjected to different training sessions during first three days. The ability to retain the learned task was tested after single, sub-acute, acute, sub-chronic and chronic exposure to above exteroceptive memory models in separate groups of animals. The memory score of all animals was recorded after 72 h, 192 h and 432 h of their last training trial. Rats of single exposure group did not show any effect on memory. Sub-acute training group animals showed improved memory up to 72 h only, where as in acute and sub-chronic training groups this memory improvement was extended up to 192 h. The rats, which were subjected to chronic exposures showed a significant improvement in retention capacity that lasted up to a period of eighteen days. These observations suggest that repeated rehearsals at regular intervals are probably necessary for consolidation of long-term memory. It was observed that sub-acute, acute and sub-chronic exposures, improved the retrieval ability of rats but this memory improving effect was short lived. Thus, rehearsal or training plays a crucial role in enhancing one's capacity of retaining the learnt information. Key PointsThe present study underlines the importance of regular rehearsals in enhancing one's capacity of retaining the learnt information. " Sub-acute, acute & sub-chronic rehearsals result in storing of information for a limited period of time.Quick decay of information or

  11. Long-term memory, sleep, and the spacing effect.

    Science.gov (United States)

    Bell, Matthew C; Kawadri, Nader; Simone, Patricia M; Wiseheart, Melody

    2014-01-01

    Many studies have shown that memory is enhanced when study sessions are spaced apart rather than massed. This spacing effect has been shown to have a lasting benefit to long-term memory when the study phase session follows the encoding session by 24 hours. Using a spacing paradigm we examined the impact of sleep and spacing gaps on long-term declarative memory for Swahili-English word pairs by including four spacing delay gaps (massed, 12 hours same-day, 12 hours overnight, and 24 hours). Results showed that a 12-hour spacing gap that includes sleep promotes long-term memory retention similar to the 24-hour gap. The findings support the importance of sleep to the long-term benefit of the spacing effect.

  12. Visual integration enhances associative memory equally for young and older adults without reducing hippocampal encoding activation.

    Science.gov (United States)

    Memel, Molly; Ryan, Lee

    2017-06-01

    The ability to remember associations between previously unrelated pieces of information is often impaired in older adults (Naveh-Benjamin, 2000). Unitization, the process of creating a perceptually or semantically integrated representation that includes both items in an associative pair, attenuates age-related associative deficits (Bastin et al., 2013; Ahmad et al., 2015; Zheng et al., 2015). Compared to non-unitized pairs, unitized pairs may rely less on hippocampally-mediated binding associated with recollection, and more on familiarity-based processes mediated by perirhinal cortex (PRC) and parahippocampal cortex (PHC). While unitization of verbal materials improves associative memory in older adults, less is known about the impact of visual integration. The present study determined whether visual integration improves associative memory in older adults by minimizing the need for hippocampal (HC) recruitment and shifting encoding to non-hippocampal medial temporal structures, such as the PRC and PHC. Young and older adults were presented with a series of objects paired with naturalistic scenes while undergoing fMRI scanning, and were later given an associative memory test. Visual integration was varied by presenting the object either next to the scene (Separated condition) or visually integrated within the scene (Combined condition). Visual integration improved associative memory among young and older adults to a similar degree by increasing the hit rate for intact pairs, but without increasing false alarms for recombined pairs, suggesting enhanced recollection rather than increased reliance on familiarity. Also contrary to expectations, visual integration resulted in increased hippocampal activation in both age groups, along with increases in PRC and PHC activation. Activation in all three MTL regions predicted discrimination performance during the Separated condition in young adults, while only a marginal relationship between PRC activation and performance was

  13. Quantum capacity of dephasing channels with memory

    International Nuclear Information System (INIS)

    D'Arrigo, A; Benenti, G; Falci, G

    2007-01-01

    We show that the amount of coherent quantum information that can be reliably transmitted down a dephasing channel with memory is maximized by separable input states. In particular, we model the channel as a Markov chain or a multimode environment of oscillators. While in the first model, the maximization is achieved for the maximally mixed input state, in the latter it is convenient to exploit the presence of a decoherence-protected subspace generated by memory effects. We explicitly compute the quantum channel capacity for the first model while numerical simulations suggest a lower bound for the latter. In both cases memory effects enhance the coherent information. We present results valid for arbitrary input size

  14. Hepatic scar in a case of healed candidiasis showing prolonged enhancement on CT

    Energy Technology Data Exchange (ETDEWEB)

    Itai, Yuji; Yashiro, Naobumi

    1987-08-01

    A patient with acute myelocytic leukemia recovering from hepatic candidiasis after long-term administration of amphotericin B had large scar in the liver which showed prominent prolonged enhancement on postcontrast CT. Prolonged enhancement can occur in regions other than hepatic masses.

  15. Platycodon grandiflorus Root Extract Improves Learning and Memory by Enhancing Synaptogenesis in Mice Hippocampus

    Directory of Open Access Journals (Sweden)

    Jin-il Kim

    2017-07-01

    Full Text Available Platycodon grandiflorus (Jacq. A.DC. (PG has long been used as an ingredient of foods and is known to have beneficial effects on cognitive functions as well. The present study examined the effect of each PG extract (PGE from root, aerial part, and seeds on cognitive functions in mice. Changes in spatial learning and memory using a Y-maze test, and markers of adult hippocampal neurogenesis and synaptogenesis were examined. Moreover, changes in neuritogenesis and activation of the ERK1/2 pathway were investigated. Results indicated that mice administered PGE (root showed increased spontaneous alternation in the Y-maze test and synaptogenesis in the hippocampus. In addition, PGE (root and platycodin D, the major bioactive compound from the PG root, significantly stimulated neuritic outgrowth by phosphorylation of the ERK1/2 signaling pathway in vitro. These results indicate that the PGE (root, containing platycodin D, enhances cognitive function through synaptogenesis via activation of the ERK1/2 signaling pathway.

  16. The role of attention in emotional memory enhancement in pathological and healthy aging.

    Science.gov (United States)

    Sava, Alina-Alexandra; Paquet, Claire; Dumurgier, Julien; Hugon, Jacques; Chainay, Hanna

    2016-01-01

    After short delays between encoding and retrieval, healthy young participants have better memory performance for emotional stimuli than for neutral stimuli. Divided-attention paradigms suggest that this emotional enhancement of memory (EEM) is due to different attention mechanisms involved during encoding: automatic processing for negative stimuli, and controlled processing for positive stimuli. As far as we know, no study on the influence of these factors on EEM in Alzheimer's disease (AD) and mild cognitive impairment (MCI) patients, as compared to healthy young and older controls, has been conducted. Thus, the goal of our study was to ascertain whether the EEM in these populations depends on the attention resources available at encoding. Participants completed two encoding phases: full attention (FA) and divided attention (DA), followed by two retrieval phases (recognition tasks). There was no EEM on the discrimination accuracy, independently of group and encoding condition. Nevertheless, all participants used a more liberal response criterion for the negative and positive stimuli than for neutral ones. In AD patients, larger numbers of false recognitions for negative and positive stimuli than for neutral ones were observed after both encoding conditions. In MCI patients and in healthy older and younger controls this effect was observed only for negative stimuli, and it depended on the encoding condition. Thus, this effect was observed in young controls after both encoding conditions, in older controls after the DA encoding, and in MCI patients after the FA encoding. In conclusion, our results suggest that emotional valence does not always enhance discrimination accuracy. Nevertheless, in certain conditions related to the attention resources available at encoding, emotional valence, especially the negative one, enhances the subjective feeling of familiarity and, consequently, engenders changes in response bias. This effect seems to be sensitive to the age and

  17. Corticotropin-releasing factor in the basolateral amygdala enhances memory consolidation via an interaction with the beta-adrenoceptor-cAMP pathway: dependence on glucocorticoid receptor activation.

    Science.gov (United States)

    Roozendaal, Benno; Schelling, Gustav; McGaugh, James L

    2008-06-25

    Extensive evidence indicates that stress hormone effects on the consolidation of emotionally influenced memory involve noradrenergic activation of the basolateral complex of the amygdala (BLA). The present experiments examined whether corticotropin-releasing factor (CRF) modulates memory consolidation via an interaction with the beta-adrenoceptor-cAMP system in the BLA. In a first experiment, male Sprague Dawley rats received bilateral infusions of the CRF-binding protein ligand inhibitor CRF(6-33) into the BLA either alone or together with the CRF receptor antagonist alpha-helical CRF(9-41) immediately after inhibitory avoidance training. CRF(6-33) induced dose-dependent enhancement of 48 h retention latencies, which was blocked by coadministration of alpha-helical CRF(9-41), suggesting that CRF(6-33) enhances memory consolidation by displacing CRF from its binding protein, thereby increasing "free" endogenous CRF concentrations. In a second experiment, intra-BLA infusions of atenolol (beta-adrenoceptor antagonist) and Rp-cAMPS (cAMP inhibitor), but not prazosin (alpha(1)-adrenoceptor antagonist), blocked CRF(6-33)-induced retention enhancement. In a third experiment, the CRF receptor antagonist alpha-helical CRF(9-41) administered into the BLA immediately after training attenuated the dose-response effects of concurrent intra-BLA infusions of clenbuterol (beta-adrenoceptor agonist). In contrast, alpha-helical CRF(9-41) did not alter retention enhancement induced by posttraining intra-BLA infusions of either cirazoline (alpha(1)-adrenoceptor agonist) or 8-br-cAMP (cAMP analog). These findings suggest that CRF facilitates the memory-modulatory effects of noradrenergic stimulation in the BLA via an interaction with the beta-adrenoceptor-cAMP cascade, at a locus between the membrane-bound beta-adrenoceptor and the intracellular cAMP formation site. Moreover, consistent with evidence that glucocorticoids enhance memory consolidation via a similar interaction with the

  18. Working-memory training improves developmental dyslexia in Chinese children

    Institute of Scientific and Technical Information of China (English)

    Yan Luo; Jing Wang; Hanrong Wu; Dongmei Zhu; Yu Zhang

    2013-01-01

    Although plasticity in the neural system underlies working memory, and working memory can be improved by training, there is thus far no evidence that children with developmental dyslexia can were recruited from an elementary school in Wuhan, China. They received working-memory training, including training in visuospatial memory, verbal memory, and central executive tasks. The difficulty of the tasks was adjusted based on the performance of each subject, and the training sessions lasted 40 minutes per day, for 5 weeks. The results showed that working-memory training significantly enhanced performance on the nontrained working memory tasks such as the visuospatial, the verbal domains, and central executive tasks in children with developmental dyslexia. More importantly, the visual rhyming task and reading fluency task were also significantly improved by training. Progress on working memory measures was related to changes in reading skills. These experimental findings indicate that working memory is a pivotal factor in reading development among children with developmental dyslexia, and interventions to improve working memory may help dyslexic children to become more proficient in reading.

  19. Amyloid-β Peptide Is Needed for cGMP-Induced Long-Term Potentiation and Memory.

    Science.gov (United States)

    Palmeri, Agostino; Ricciarelli, Roberta; Gulisano, Walter; Rivera, Daniela; Rebosio, Claudia; Calcagno, Elisa; Tropea, Maria Rosaria; Conti, Silvia; Das, Utpal; Roy, Subhojit; Pronzato, Maria Adelaide; Arancio, Ottavio; Fedele, Ernesto; Puzzo, Daniela

    2017-07-19

    High levels of amyloid-β peptide (Aβ) have been related to Alzheimer's disease pathogenesis. However, in the healthy brain, low physiologically relevant concentrations of Aβ are necessary for long-term potentiation (LTP) and memory. Because cGMP plays a key role in these processes, here we investigated whether the cyclic nucleotide cGMP influences Aβ levels and function during LTP and memory. We demonstrate that the increase of cGMP levels by the phosphodiesterase-5 inhibitors sildenafil and vardenafil induces a parallel release of Aβ due to a change in the approximation of amyloid precursor protein (APP) and the β-site APP cleaving enzyme 1. Moreover, electrophysiological and behavioral studies performed on animals of both sexes showed that blocking Aβ function, by using anti-murine Aβ antibodies or APP knock-out mice, prevents the cGMP-dependent enhancement of LTP and memory. Our data suggest that cGMP positively regulates Aβ levels in the healthy brain which, in turn, boosts synaptic plasticity and memory. SIGNIFICANCE STATEMENT Amyloid-β (Aβ) is a key pathogenetic factor in Alzheimer's disease. However, low concentrations of endogenous Aβ, mimicking levels of the peptide in the healthy brain, enhance hippocampal long-term potentiation (LTP) and memory. Because the second messenger cGMP exerts a central role in LTP mechanisms, here we studied whether cGMP affects Aβ levels and function during LTP. We show that cGMP enhances Aβ production by increasing the APP/BACE-1 convergence in endolysosomal compartments. Moreover, the cGMP-induced enhancement of LTP and memory was disrupted by blockade of Aβ, suggesting that the physiological effect of the cyclic nucleotide on LTP and memory is dependent upon Aβ. Copyright © 2017 the authors 0270-6474/17/376926-12$15.00/0.

  20. Making Memories Matter

    OpenAIRE

    Gold, Paul E.; Korol, Donna L.

    2012-01-01

    This article reviews some of the neuroendocrine bases by which emotional events regulate brain mechanisms of learning and memory. In laboratory rodents, there is extensive evidence that epinephrine influences memory processing through an inverted-U relationship, at which moderate levels enhance and high levels impair memory. These effects are, in large part, mediated by increases in blood glucose levels subsequent to epinephrine release, which then provide support for the brain processes en...

  1. Hepatic scar in a case of healed candidiasis showing prolonged enhancement on CT

    International Nuclear Information System (INIS)

    Itai, Yuji; Yashiro, Naobumi

    1987-01-01

    A patient with acute myelocytic leukemia recovering from hepatic candidiasis after long-term administration of amphotericin B had large scar in the liver which showed prominent prolonged enhancement on postcontrast CT. Prolonged enhancement can occur in regions other than hepatic masses. (author)

  2. Working memory load and the retro-cue effect: A diffusion model account.

    Science.gov (United States)

    Shepherdson, Peter; Oberauer, Klaus; Souza, Alessandra S

    2018-02-01

    Retro-cues (i.e., cues presented between the offset of a memory array and the onset of a probe) have consistently been found to enhance performance in working memory tasks, sometimes ameliorating the deleterious effects of increased memory load. However, the mechanism by which retro-cues exert their influence remains a matter of debate. To inform this debate, we applied a hierarchical diffusion model to data from 4 change detection experiments using single item, location-specific probes (i.e., a local recognition task) with either visual or verbal memory stimuli. Results showed that retro-cues enhanced the quality of information entering the decision process-especially for visual stimuli-and decreased the time spent on nondecisional processes. Further, cues interacted with memory load primarily on nondecision time, decreasing or abolishing load effects. To explain these findings, we propose an account whereby retro-cues act primarily to reduce the time taken to access the relevant representation in memory upon probe presentation, and in addition protect cued representations from visual interference. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  3. Nicotine facilitates memory consolidation in perceptual learning.

    Science.gov (United States)

    Beer, Anton L; Vartak, Devavrat; Greenlee, Mark W

    2013-01-01

    Perceptual learning is a special type of non-declarative learning that involves experience-dependent plasticity in sensory cortices. The cholinergic system is known to modulate declarative learning. In particular, reduced levels or efficacy of the neurotransmitter acetylcholine were found to facilitate declarative memory consolidation. However, little is known about the role of the cholinergic system in memory consolidation of non-declarative learning. Here we compared two groups of non-smoking men who learned a visual texture discrimination task (TDT). One group received chewing tobacco containing nicotine for 1 h directly following the TDT training. The other group received a similar tasting control substance without nicotine. Electroencephalographic recordings during substance consumption showed reduced alpha activity and P300 latencies in the nicotine group compared to the control group. When re-tested on the TDT the following day, both groups responded more accurately and more rapidly than during training. These improvements were specific to the retinal location and orientation of the texture elements of the TDT suggesting that learning involved early visual cortex. A group comparison showed that learning effects were more pronounced in the nicotine group than in the control group. These findings suggest that oral consumption of nicotine enhances the efficacy of nicotinic acetylcholine receptors. Our findings further suggest that enhanced efficacy of the cholinergic system facilitates memory consolidation in perceptual learning (and possibly other types of non-declarative learning). In that regard acetylcholine seems to affect consolidation processes in perceptual learning in a different manner than in declarative learning. Alternatively, our findings might reflect dose-dependent cholinergic modulation of memory consolidation. This article is part of a Special Issue entitled 'Cognitive Enhancers'. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Gut memories do not fade: epigenetic regulation of lasting gut homing receptor expression in CD4+ memory T cells.

    Science.gov (United States)

    Szilagyi, B A; Triebus, J; Kressler, C; de Almeida, M; Tierling, S; Durek, P; Mardahl, M; Szilagyi, A; Floess, S; Huehn, J; Syrbe, U; Walter, J; Polansky, J K; Hamann, A

    2017-11-01

    The concept of a "topographical memory" in lymphocytes implies a stable expression of homing receptors mediating trafficking of lymphocytes back to the tissue of initial activation. However, a significant plasticity of the gut-homing receptor α 4 β 7 was found in CD8 + T cells, questioning the concept. We now demonstrate that α 4 β 7 expression in murine CD4 + memory T cells is, in contrast, imprinted and remains stable in the absence of the inducing factor retinoic acid (RA) or other stimuli from mucosal environments. Repetitive rounds of RA treatment enhanced the stability of de novo induced α 4 β 7 . A novel enhancer element in the murine Itga4 locus was identified that showed, correlating to stability, selective DNA demethylation in mucosa-seeking memory cells and methylation-dependent transcriptional activity in a reporter gene assay. This implies that epigenetic mechanisms contribute to the stabilization of α 4 β 7 expression. Analogous DNA methylation patterns could be observed in the human ITGA4 locus, suggesting that its epigenetic regulation is conserved between mice and men. These data prove that mucosa-specific homing mediated by α 4 β 7 is imprinted in CD4 + memory T cells, reinstating the validity of the concept of "topographical memory" for mucosal tissues, and imply a critical role of epigenetic mechanisms.

  5. Motivation Matters: Differing Effects of Pre-Goal and Post-Goal Emotions on Attention and Memory

    OpenAIRE

    Kaplan, Robin L.; Van Damme, Ilse; Levine, Linda J.

    2012-01-01

    People often show enhanced memory for information that is central to emotional events and impaired memory for peripheral details. The intensity of arousal elicited by an emotional event is commonly held to be the mechanism underlying memory narrowing, with the implication that all sources of emotional arousal should have comparable effects. Discrete emotions differ in their effects on memory, however, with some emotions broadening rather than narrowing the range of information attended to and...

  6. How Arousal Affects Younger and Older Adults' Memory Binding

    Science.gov (United States)

    Nashiro, Kaoru; Mather, Mara

    2009-01-01

    A number of recent studies have shown that associative memory for within-item features is enhanced for emotionally arousing items, whereas arousal-enhanced binding is not seen for associations between distinct items (for a review see Mather, 2007). The costs and benefits of arousal in memory binding have been examined for younger adults but not for older adults. The present experiment examined whether arousal would enhance younger and older adults' within-item and between-item memory binding. The results revealed that arousal improved younger adults' within-item memory binding but not that of older adults. Arousal worsened both groups' between-item memory binding. PMID:21240821

  7. The selective A-type K+ current blocker Tx3-1 isolated from the Phoneutria nigriventer venom enhances memory of naïve and Aβ(25-35)-treated mice.

    Science.gov (United States)

    Gomes, Guilherme M; Dalmolin, Gerusa D; Cordeiro, Marta do Nascimento; Gomez, Marcus V; Ferreira, Juliano; Rubin, Maribel A

    2013-12-15

    Potassium channels regulate many neuronal functions, including neuronal excitability and synaptic plasticity, contributing, by these means, to mnemonic processes. In particular, A-type K(+) currents (IA) play a key role in hippocampal synaptic plasticity. Therefore, we evaluated the effect of the peptidic toxin Tx3-1, a selective blocker of IA currents, extracted from the venom of the spider Phoneutria nigriventer, on memory of mice. Administration of Tx3-1 (i.c.v., 300 pmol/site) enhanced both short- and long-term memory consolidation of mice tested in the novel object recognition task. In comparison, 4-aminopyridine (4-AP; i.c.v., 30-300 pmol/site), a non-selective K(+) channel blocker did not alter long-term memory and caused toxic side effects such as circling, freezing and tonic-clonic seizures. Moreover, Tx3-1 (i.c.v., 10-100 pmol/site) restored memory of Aβ25-35-injected mice, and exhibited a higher potency to improve memory of Aβ25-35-injected mice when compared to control group. These results show the effect of the selective blocker of IA currents Tx3-1 in both short- and long-term memory retention and in memory impairment caused by Aβ25-35, reinforcing the role of IA in physiological and pathological memory processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Improving Outcome of Psychosocial Treatments by Enhancing Memory and Learning

    Science.gov (United States)

    Harvey, Allison G.; Lee, Jason; Williams, Joseph; Hollon, Steven D.; Walker, Matthew P.; Thompson, Monique A.; Smith, Rita

    2014-01-01

    Mental disorders are prevalent and lead to significant impairment. Progress toward establishing treatments has been good. However, effect sizes are small to moderate, gains may not persist, and many patients derive no benefit. Our goal is to highlight the potential for empirically-supported psychosocial treatments to be improved by incorporating insights from cognitive psychology and research on education. Our central question is: If it were possible to improve memory for content of sessions of psychosocial treatments, would outcome substantially improve? This question arises from five lines of evidence: (a) mental illness is often characterized by memory impairment, (b) memory impairment is modifiable, (c) psychosocial treatments often involve the activation of emotion, (d) emotion can bias memory and (e) memory for psychosocial treatment sessions is poor. Insights from scientific knowledge on learning and memory are leveraged to derive strategies for a transdiagnostic and transtreatment cognitive support intervention. These strategies can be applied within and between sessions and to interventions delivered via computer, the internet and text message. Additional novel pathways to improving memory include improving sleep, engaging in exercise and imagery. Given that memory processes change across the lifespan, services to children and older adults may benefit from cognitive support. PMID:25544856

  9. [Nostalgia and the functions of autobiographical memory].

    Science.gov (United States)

    Wolf, T

    2014-11-01

    Current research on autobiographical memory distinguishes between a self function, a directive function, and a social function of autobiographical memory. From a lifespan perspective, the use of autobiographical memory for these functions is expected to decrease with age. The present study extended these functions by the function of nostalgia: Often triggered by negative emotions, remembering personal and positive experiences might, among others, enhance positive effects. This emotion-regulating function is expected to become more important in old age. In the present study 273 adults (aged between 19 and 90 years) completed the Thinking About Life Experiences Questionnaire (TALE) as well as 11 newly developed items to assess the nostalgia function. Exploratory and confirmatory factor analyses supported a four-factor model reflecting the presumed self, directive, social, and nostalgia functions of autobiographical memory. The results showed a decrease in the use of autobiographical memory for self, directive and social functions with increasing age, whereas the nostalgia function followed a U-shaped pattern.

  10. The Role of Emotional Landmarks on Topographical Memory.

    Science.gov (United States)

    Palmiero, Massimiliano; Piccardi, Laura

    2017-01-01

    The investigation of the role of emotional landmarks on human navigation has been almost totally neglected in psychological research. Therefore, the extent to which positive and negative emotional landmarks affect topographical memory as compared to neutral emotional landmark was explored. Positive, negative and neutral affect-laden images were selected as landmarks from the International Affective Picture System (IAPS) Inventory. The Walking Corsi test (WalCT) was used in order to test the landmark-based topographical memory. Participants were instructed to learn and retain an eight-square path encompassing positive, negative or neutral emotional landmarks. Both egocentric and allocentric frames of references were considered. Egocentric representation encompasses the object's relation to the self and it is generated from sensory data. Allocentric representation expresses a location with respect to an external frame regardless of the self and it is the basis for long-term storage of complex layouts. In particular, three measures of egocentric and allocentric topographical memory were taken into account: (1) the ability to learn the path; (2) the ability to recall by walking the path five minutes later; (3) the ability to reproduce the path on the outline of the WalCT. Results showed that both positive and negative emotional landmarks equally enhanced the learning of the path as compared to neutral emotional landmarks. In addition, positive emotional landmarks improved the reproduction of the path on the map as compared to negative and neutral emotional landmarks. These results generally show that emotional landmarks enhance egocentric-based topographical memory, whereas positive emotional landmarks seem to be more effective for allocentric-based topographical memory.

  11. Controlling memory impairment in elderly adults using virtual reality memory training: a randomized controlled pilot study.

    Science.gov (United States)

    Optale, Gabriele; Urgesi, Cosimo; Busato, Valentina; Marin, Silvia; Piron, Lamberto; Priftis, Konstantinos; Gamberini, Luciano; Capodieci, Salvatore; Bordin, Adalberto

    2010-05-01

    Memory decline is a prevalent aspect of aging but may also be the first sign of cognitive pathology. Virtual reality (VR) using immersion and interaction may provide new approaches to the treatment of memory deficits in elderly individuals. The authors implemented a VR training intervention to try to lessen cognitive decline and improve memory functions. The authors randomly assigned 36 elderly residents of a rest care facility (median age 80 years) who were impaired on the Verbal Story Recall Test either to the experimental group (EG) or the control group (CG). The EG underwent 6 months of VR memory training (VRMT) that involved auditory stimulation and VR experiences in path finding. The initial training phase lasted 3 months (3 auditory and 3 VR sessions every 2 weeks), and there was a booster training phase during the following 3 months (1 auditory and 1 VR session per week). The CG underwent equivalent face-to-face training sessions using music therapy. Both groups participated in social and creative and assisted-mobility activities. Neuropsychological and functional evaluations were performed at baseline, after the initial training phase, and after the booster training phase. The EG showed significant improvements in memory tests, especially in long-term recall with an effect size of 0.7 and in several other aspects of cognition. In contrast, the CG showed progressive decline. The authors suggest that VRMT may improve memory function in elderly adults by enhancing focused attention.

  12. Effects on Inter-Personal Memory of Dancing in Time with Others.

    Science.gov (United States)

    Woolhouse, Matthew H; Tidhar, Dan; Cross, Ian

    2016-01-01

    We report an experiment investigating whether dancing to the same music enhances recall of person-related memory targets. The experiment used 40 dancers (all of whom were unaware of the experiment's aim), two-channel silent-disco radio headphones, a marked-up dance floor, two types of music, and memory targets (sash colors and symbols). In each trial, 10 dancers wore radio headphones and one of four different colored sashes, half of which carried cat symbols. Using silent-disco technology, one type of music was surreptitiously transmitted to half the dancers, while music at a different tempo was transmitted to the remaining dancers. Pre-experiment, the dancers' faces were photographed. Post-experiment, each dancer was presented with the photographs of the other dancers and asked to recall their memory targets. Results showed that same-music dancing significantly enhanced memory for sash color and sash symbol. Our findings are discussed in light of recent eye-movement research that showed significantly increased gaze durations for people observing music-dance synchrony versus music-dance asynchrony, and in relation to current literature on interpersonal entrainment, group cohesion, and social bonding.

  13. Dynamics of Hippocampal Protein Expression During Long-term Spatial Memory Formation*

    Science.gov (United States)

    Borovok, Natalia; Nesher, Elimelech; Levin, Yishai; Reichenstein, Michal; Pinhasov, Albert

    2016-01-01

    Spatial memory depends on the hippocampus, which is particularly vulnerable to aging. This vulnerability has implications for the impairment of navigation capacities in older people, who may show a marked drop in performance of spatial tasks with advancing age. Contemporary understanding of long-term memory formation relies on molecular mechanisms underlying long-term synaptic plasticity. With memory acquisition, activity-dependent changes occurring in synapses initiate multiple signal transduction pathways enhancing protein turnover. This enhancement facilitates de novo synthesis of plasticity related proteins, crucial factors for establishing persistent long-term synaptic plasticity and forming memory engrams. Extensive studies have been performed to elucidate molecular mechanisms of memory traces formation; however, the identity of plasticity related proteins is still evasive. In this study, we investigated protein turnover in mouse hippocampus during long-term spatial memory formation using the reference memory version of radial arm maze (RAM) paradigm. We identified 1592 proteins, which exhibited a complex picture of expression changes during spatial memory formation. Variable linear decomposition reduced significantly data dimensionality and enriched three principal factors responsible for variance of memory-related protein levels at (1) the initial phase of memory acquisition (165 proteins), (2) during the steep learning improvement (148 proteins), and (3) the final phase of the learning curve (123 proteins). Gene ontology and signaling pathways analysis revealed a clear correlation between memory improvement and learning phase-curbed expression profiles of proteins belonging to specific functional categories. We found differential enrichment of (1) neurotrophic factors signaling pathways, proteins regulating synaptic transmission, and actin microfilament during the first day of the learning curve; (2) transcription and translation machinery, protein

  14. Dynamics of Hippocampal Protein Expression During Long-term Spatial Memory Formation.

    Science.gov (United States)

    Borovok, Natalia; Nesher, Elimelech; Levin, Yishai; Reichenstein, Michal; Pinhasov, Albert; Michaelevski, Izhak

    2016-02-01

    Spatial memory depends on the hippocampus, which is particularly vulnerable to aging. This vulnerability has implications for the impairment of navigation capacities in older people, who may show a marked drop in performance of spatial tasks with advancing age. Contemporary understanding of long-term memory formation relies on molecular mechanisms underlying long-term synaptic plasticity. With memory acquisition, activity-dependent changes occurring in synapses initiate multiple signal transduction pathways enhancing protein turnover. This enhancement facilitates de novo synthesis of plasticity related proteins, crucial factors for establishing persistent long-term synaptic plasticity and forming memory engrams. Extensive studies have been performed to elucidate molecular mechanisms of memory traces formation; however, the identity of plasticity related proteins is still evasive. In this study, we investigated protein turnover in mouse hippocampus during long-term spatial memory formation using the reference memory version of radial arm maze (RAM) paradigm. We identified 1592 proteins, which exhibited a complex picture of expression changes during spatial memory formation. Variable linear decomposition reduced significantly data dimensionality and enriched three principal factors responsible for variance of memory-related protein levels at (1) the initial phase of memory acquisition (165 proteins), (2) during the steep learning improvement (148 proteins), and (3) the final phase of the learning curve (123 proteins). Gene ontology and signaling pathways analysis revealed a clear correlation between memory improvement and learning phase-curbed expression profiles of proteins belonging to specific functional categories. We found differential enrichment of (1) neurotrophic factors signaling pathways, proteins regulating synaptic transmission, and actin microfilament during the first day of the learning curve; (2) transcription and translation machinery, protein

  15. Overcoming the drawback of lower sense margin in tunnel FET based dynamic memory along with enhanced charge retention and scalability

    Science.gov (United States)

    Navlakha, Nupur; Kranti, Abhinav

    2017-11-01

    The work reports on the use of a planar tri-gate tunnel field effect transistor (TFET) to operate as dynamic memory at 85 °C with an enhanced sense margin (SM). Two symmetric gates (G1) aligned to the source at a partial region of intrinsic film result into better electrostatic control that regulates the read mechanism based on band-to-band tunneling, while the other gate (G2), positioned adjacent to the first front gate is responsible for charge storage and sustenance. The proposed architecture results in an enhanced SM of ˜1.2 μA μm-1 along with a longer retention time (RT) of ˜1.8 s at 85 °C, for a total length of 600 nm. The double gate architecture towards the source increases the tunneling current and also reduces short channel effects, enhancing SM and scalability, thereby overcoming the critical bottleneck faced by TFET based dynamic memories. The work also discusses the impact of overlap/underlap and interface charges on the performance of TFET based dynamic memory. Insights into device operation demonstrate that the choice of appropriate architecture and biases not only limit the trade-off between SM and RT, but also result in improved scalability with drain voltage and total length being scaled down to 0.8 V and 115 nm, respectively.

  16. Inhibiting corticosterone synthesis during fear memory formation exacerbates cued fear extinction memory deficits within the single prolonged stress model.

    Science.gov (United States)

    Keller, Samantha M; Schreiber, William B; Stanfield, Briana R; Knox, Dayan

    2015-01-01

    Using the single prolonged stress (SPS) animal model of post-traumatic stress disorder (PTSD), previous studies suggest that enhanced glucocorticoid receptor (GR) expression leads to cued fear extinction retention deficits. However, it is unknown how the endogenous ligand of GRs, corticosterone (CORT), may contribute to extinction retention deficits in the SPS model. Given that CORT synthesis during fear learning is critical for fear memory consolidation and SPS enhances GR expression, CORT synthesis during fear memory formation could strengthen fear memory in SPS rats by enhancing GR activation during fear learning. In turn, this could lead to cued fear extinction retention deficits. We tested the hypothesis that CORT synthesis during fear learning leads to cued fear extinction retention deficits in SPS rats by administering the CORT synthesis inhibitor metyrapone to SPS and control rats prior to fear conditioning, and observed the effect this had on extinction memory. Inhibiting CORT synthesis during fear memory formation in control rats tended to decrease cued freezing, though this effect never reached statistical significance. Contrary to our hypothesis, inhibiting CORT synthesis during fear memory formation disrupted extinction retention in SPS rats. This finding suggests that even though SPS exposure leads to cued fear extinction memory deficits, CORT synthesis during fear memory formation enhances extinction retention in SPS rats. This suggests that stress-induced CORT synthesis in previously stressed rats can be beneficial. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Learning and memory enhancing activity of Ficus carica (Fig: An experimental study in rats

    Directory of Open Access Journals (Sweden)

    Meera Sumanth

    2014-01-01

    Full Text Available Objective: The study aimed to assess the learning and memory enhancing activity of the ethanolic fruit extract of Ficus carica in rats using elevated plus maze (EPM, Hebb-William maze (HWM and Morris water maze (MWM. Materials and Methods: Wistar rats (100-150 g of either sex, were divided into 5 groups (n = 6. Group I (control animals received vehicle, Group II (scopolamine control animals received scopolamine (0.4 mg/kg i.p, Groups III and IV animals received ethanolic fruit extract of F. carica (200 mg/kg and 400 mg/kg p.o and Group V animals received piracetam (400 mg/kg i.p for 27 days. The rats of Groups III-V were injected with a single dose of scopolamine (0.4 mg/kg i.p on 19 th and 27 th day. Assessment of transfer latency (TL, time taken to reach reward chamber (TRC and swim latency (SL was done on 19 th and 27 th day using EPM, HWM and MWM, respectively. The data was analyzed by one-way Analysis of Variance followed by Dunnett′s test. P ≤ 0.05 was considered to be significant. Results: Ethanolic fruit extract of F. carica decreased TL, TRC and SL in comparison to scopolamine treated rats. Conclusion: The fruit of F. carica enhanced learning and memory activity.

  18. Differential immediate and sustained memory enhancing effects of alpha7 nicotinic receptor agonists and allosteric modulators in rats.

    Directory of Open Access Journals (Sweden)

    Morten S Thomsen

    Full Text Available The α7 nicotinic acetylcholine receptor (nAChR is a potential target for the treatment of cognitive deficits in patients with schizophrenia, ADHD and Alzheimer's disease. Here we test the hypothesis that upregulation of α7 nAChR levels underlies the enhanced and sustained procognitive effect of repeated administration of α7 nAChR agonists. We further compare the effect of agonists to that of α7 nAChR positive allosteric modulators (PAMs, which do not induce upregulation of the α7 nAChR. Using the social discrimination test as a measure of short-term memory, we show that the α7 nAChR agonist A-582941 improves short-term memory immediately after repeated (7× daily, but not a single administration. The α7 nAChR PAMs PNU-120596 and AVL-3288 do not affect short-term memory immediately after a single or repeated administration. This demonstrates a fundamental difference in the behavioral effects of agonists and PAMs that may be relevant for clinical development. Importantly, A-582941 and AVL-3288 increase short-term memory 24 hrs after repeated, but not a single, administration, suggesting that repeated administration of both agonists and PAMs may produce sustained effects on cognitive performance. Subsequent [(125I]-bungarotoxin autoradiography revealed no direct correlation between α7 nAChR levels in frontal cortical or hippocampal brain regions and short-term memory with either compound. Additionally, repeated treatment with A-582941 did not affect mRNA expression of RIC-3 or the lynx-like gene products lynx1, lynx2, PSCA, or Ly6H, which are known to affect nAChR function. In conclusion, both α7 nAChR agonists and PAMs exhibit sustained pro-cognitive effects after repeated administration, and altered levels of the α7 nAChR per se, or that of endogenous regulators of nAChR function, are likely not the major cause of this effect.

  19. Role of glucocorticoid receptor-mediated mechanisms in cocaine memory enhancement.

    Science.gov (United States)

    Stringfield, S J; Higginbotham, J A; Wang, R; Berger, A L; McLaughlin, R J; Fuchs, R A

    2017-09-01

    The basolateral amygdala (BLA) is a critical site for the reconsolidation of labile contextual cocaine memories following retrieval-induced reactivation/destabilization. Here, we examined whether glucocorticoid receptors (GR), which are abundant in the BLA, mediate this phenomenon. Rats were trained to lever press for cocaine reinforcement in a distinct environmental context, followed by extinction training in a different context. Rats were then briefly exposed to the cocaine-paired context (to elicit memory reactivation and reconsolidation) or their home cages (no reactivation control). Exposure to the cocaine-paired context elicited greater serum corticosterone concentrations than home cage stay. Interestingly, the GR antagonist, mifepristone (3-10 ng/hemisphere), administered into the BLA after memory reactivation produced a further, dose-dependent increase in serum corticosterone concentrations during the putative time of cocaine-memory reconsolidation but produced an inverted U-shaped dose-effect curve on subsequent cocaine-seeking behavior 72 h later. This effect was anatomically selective, dependent on memory reactivation (i.e., not observed after home cage exposure), and did not reflect protracted hyperactivity. However, the effect was also observed when mifepristone was administered after novelty stress that mimics drug context-induced hypothalamic-pituitary-adrenal (HPA) axis activation without explicit memory reactivation. Together, these findings suggest that, similar to explicit memory retrieval, a stressful event is sufficient to destabilize cocaine memories and permit their manipulation. Furthermore, BLA GR stimulation exerts inhibitory feedback upon HPA axis activation and thus suppresses cocaine-memory reconsolidation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. PMC-12, a traditional herbal medicine, enhances learning memory and hippocampal neurogenesis in mice.

    Science.gov (United States)

    Park, Hee Ra; Kim, Ju Yeon; Lee, Yujeong; Chun, Hye Jeong; Choi, Young Whan; Shin, Hwa Kyoung; Choi, Byung Tae; Kim, Cheol Min; Lee, Jaewon

    2016-03-23

    The beneficial effects of traditional Korean medicine are recognized during the treatment of neurodegenerative conditions, such as, Alzheimer's disease and neurocognitive dysfunction, and recently, hippocampal neurogenesis has been reported to be associated with memory function. In this study, the authors investigated the beneficial effects of polygonum multiflorum Thunberg complex composition-12 (PMC-12), which is a mixture of four medicinal herbs, that is, Polygonum multiflorum, Polygala tenuifolia, Rehmannia glutinosa, and Acorus gramineus, on hippocampal neurogenesis, learning, and memory in mice. PMC-12 was orally administered to male C57BL/6 mice (5 weeks old) at 100 or 500 mg/kg daily for 2 weeks. PMC-12 administration significantly was found to increase the proliferation of neural progenitor cells and the survival of newly-generated cells in the dentate gyrus. In the Morris water maze test, the latency times of PMC-12 treated mice (100 or 500 mg/kg) were shorter than those of vehicle-control mice. In addition, PMC-12 increased the levels of BDNF, p-CREB, and synaptophysin, which are known to be associated with neural plasticity and hippocampal neurogenesis. These findings suggest PMC-12 enhances hippocampal neurogenesis and neurocognitive function and imply that PMC-12 ameliorates memory impairment and cognitive deficits. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Dl-3-n-Butylphthalide Treatment Enhances Hemodynamics and Ameliorates Memory Deficits in Rats with Chronic Cerebral Hypoperfusion

    Directory of Open Access Journals (Sweden)

    Zhilin Xiong

    2017-07-01

    Full Text Available Our previous study has revealed that chronic cerebral hypoperfusion (CCH activates a compensatory vascular mechanism attempting to maintain an optimal cerebral blood flow (CBF. However, this compensation fails to prevent neuronal death and cognitive impairment because neurons die prior to the restoration of normal CBF. Therefore, pharmacological invention may be critical to enhance the CBF for reducing neurodegeneration and memory deficit. Dl-3-n-butylphthalide (NBP is a compound isolated from the seeds of Chinese celery and has been proven to be able to prevent neuronal loss, reduce inflammation and ameliorate memory deficits in acute ischemic animal models and stroke patients. In the present study, we used magnetic resonance imaging (MRI techniques, immunohistochemistry and Morris water maze (MWM to investigate whether NBP can accelerate CBF recovery, reduce neuronal death and improve cognitive deficits in CCH rats after permanent bilateral common carotid artery occlusion (BCCAO. Rats were intravenously injected with NBP (5 mg/kg daily for 14 days beginning the first day after BCCAO. The results showed that NBP shortened recovery time of CBF to pre-occlusion levels at 2 weeks following BCCAO, compared to 4 weeks in the vehicle group, and enhanced hemodynamic compensation through dilation of the vertebral arteries (VAs and increase in angiogenesis. NBP treatment also markedly reduced reactive astrogliosis and cell apoptosis and protected hippocampal neurons against ischemic injury. The escape latency of CCH rats in the MWM was also reduced in response to NBP treatment. These findings demonstrate that NBP can accelerate the recovery of CBF and improve cognitive function in a rat model of CCH, suggesting that NBP is a promising therapy for CCH patients or vascular dementia.

  2. Nigella sativa Oil Enhances the Spatial Working Memory Performance of Rats on a Radial Arm Maze

    Directory of Open Access Journals (Sweden)

    Mohamad Khairul Azali Sahak

    2013-01-01

    Full Text Available Nigella sativa, an established historical and religion-based remedy for a wide range of health problems, is a herbal medicine known to have antioxidant and neuroprotective effects. This present study investigated the effect of Nigella sativa oil (NSO administration on the spatial memory performance (SMP of male adult rats using eight-arm radial arm maze (RAM. Twelve Sprague Dawley rats (7–9 weeks old were force-fed daily with 6.0 μL/100 g body weight of Nigella sativa oil (NSO group; n=6 or 0.1 mL/100 g body weight of corn oil (control (CO group; n=6 for a period of 20 consecutive weeks. For each weekly evaluation of SMP, one day food-deprived rats were tested by allowing each of them 3 minutes to explore th