Recognition Memory, Self-Other Source Memory, and Theory-of-Mind in Children with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Lind, Sophie E.; Bowler, Dermot M.

2009-01-01

This study investigated semantic and episodic memory in autism spectrum disorder (ASD), using a task which assessed recognition and self-other source memory. Children with ASD showed undiminished recognition memory but significantly diminished source memory, relative to age- and verbal ability-matched comparison children. Both children with and…

Estradiol and luteinizing hormone regulate recognition memory following subchronic phencyclidine: Evidence for hippocampal GABA action.

PubMed

Riordan, Alexander J; Schaler, Ari W; Fried, Jenny; Paine, Tracie A; Thornton, Janice E

2018-05-01

The cognitive symptoms of schizophrenia are poorly understood and difficult to treat. Estrogens may mitigate these symptoms via unknown mechanisms. To examine these mechanisms, we tested whether increasing estradiol (E) or decreasing luteinizing hormone (LH) could mitigate short-term episodic memory loss in a phencyclidine (PCP) model of schizophrenia. We then assessed whether changes in cortical or hippocampal GABA may underlie these effects. Female rats were ovariectomized and injected subchronically with PCP. To modulate E and LH, animals received estradiol capsules or Antide injections. Short-term episodic memory was assessed using the novel object recognition task (NORT). Brain expression of GAD67 was analyzed via western blot, and parvalbumin-containing cells were counted using immunohistochemistry. Some rats received hippocampal infusions of a GABA A agonist, GABA A antagonist, or GAD inhibitor before behavioral testing. We found that PCP reduced hippocampal GAD67 and abolished recognition memory. Antide restored hippocampal GAD67 and rescued recognition memory in PCP-treated animals. Estradiol prevented PCP's amnesic effect in NORT but failed to restore hippocampal GAD67. PCP did not cause significant differences in number of parvalbumin-expressing cells or cortical expression of GAD67. Hippocampal infusions of a GABA A agonist restored recognition memory in PCP-treated rats. Blocking hippocampal GAD or GABA A receptors in ovx animals reproduced recognition memory loss similar to PCP and inhibited estradiol's protection of recognition memory in PCP-treated animals. In summary, decreasing LH or increasing E can lessen short-term episodic memory loss, as measured by novel object recognition, in a PCP model of schizophrenia. Alterations in hippocampal GABA may contribute to both PCP's effects on recognition memory and the hormones' ability to prevent or reverse them. Copyright © 2018 Elsevier Ltd. All rights reserved.

Behavioural and magnetoencephalographic evidence for the interaction between semantic and episodic memory in healthy elderly subjects.

PubMed

La Corte, Valentina; Dalla Barba, Gianfranco; Lemaréchal, Jean-Didier; Garnero, Line; George, Nathalie

2012-10-01

The relationship between episodic and semantic memory systems has long been debated. Some authors argue that episodic memory is contingent on semantic memory (Tulving 1984), while others postulate that both systems are independent since they can be selectively damaged (Squire 1987). The interaction between these memory systems is particularly important in the elderly, since the dissociation of episodic and semantic memory defects characterize different aging-related pathologies. Here, we investigated the interaction between semantic knowledge and episodic memory processes associated with faces in elderly subjects using an experimental paradigm where the semantic encoding of famous and unknown faces was compared to their episodic recognition. Results showed that the level of semantic awareness of items affected the recognition of those items in the episodic memory task. Event-related magnetic fields confirmed this interaction between episodic and semantic memory: ERFs related to the old/new effect during the episodic task were markedly different for famous and unknown faces. The old/new effect for famous faces involved sustained activities maximal over right temporal sensors, showing a spatio-temporal pattern partly similar to that found for famous versus unknown faces during the semantic task. By contrast, an old/new effect for unknown faces was observed on left parieto-occipital sensors. These findings suggest that the episodic memory for famous faces activated the retrieval of stored semantic information, whereas it was based on items' perceptual features for unknown faces. Overall, our results show that semantic information interfered markedly with episodic memory processes and suggested that the neural substrates of these two memory systems overlap.

Preserved recognition in a case of developmental amnesia: implications for the acquisition of semantic memory?

PubMed

Baddeley, A; Vargha-Khadem, F; Mishkin, M

2001-04-01

We report the performance on recognition memory tests of Jon, who, despite amnesia from early childhood, has developed normal levels of performance on tests of intelligence, language, and general knowledge. Despite impaired recall, he performed within the normal range on each of six recognition tests, but he appears to lack the recollective phenomenological experience normally associated with episodic memory. His recall of previously unfamiliar newsreel events was impaired, but gained substantially from repetition over a 2-day period. Our results are consistent with the hypothesis that the recollective process of episodic memory is not necessary either for recognition or for the acquisition of semantic knowledge.

Episodic memory retrieval in adolescents with and without developmental language disorder (DLD).

PubMed

Lee, Joanna C

2018-03-01

Two reasons may explain the discrepant findings regarding declarative memory in developmental language disorder (DLD) in the literature. First, standardized tests are one of the primary tools used to assess declarative memory in previous studies. It is possible they are not sensitive enough to subtle memory impairment. Second, the system underlying declarative memory is complex, and thus results may vary depending on the types of encoding and retrieval processes measured (e.g., item specific or relational) and/or task demands (e.g., recall or recognition during memory retrieval). To adopt an experimental paradigm to examine episodic memory functioning in adolescents with and without DLD, with the focus on memory recognition of item-specific and relational information. Two groups of adolescents, one with DLD (n = 23; mean age = 16.73 years) and the other without (n = 23; mean age = 16.75 years), participated in the study. The Relational and Item-Specific Encoding (RISE) paradigm was used to assess the effect of different encoding processes on episodic memory retrieval in DLD. The advantage of using the RISE task is that both item-specific and relational encoding/retrieval can be examined within the same learning paradigm. Adolescents with DLD and those with typical language development showed comparable engagement during the encoding phase. The DLD group showed significantly poorer item recognition than the comparison group. Associative recognition was not significantly different between the two groups; however, there was a non-significant trend for to be poorer in the DLD group than in the comparison group, suggesting a possible impairment in associative recognition in individuals with DLD, but to a lesser magnitude. These results indicate that adolescents with DLD have difficulty with episodic memory retrieval when stimuli are encoded and retrieved without support from contextual information. Associative recognition is relatively less affected than item recognition in adolescents with DLD. © 2017 Royal College of Speech and Language Therapists.

Mechanisms underlying the production of false memories for famous people's names in aging and Alzheimer's disease.

PubMed

Plancher, Gaën; Guyard, Anne; Nicolas, Serge; Piolino, Pascale

2009-10-01

It is well known that the occurrence of false memories increases with aging, but the results remain inconsistent concerning Alzheimer's disease (AD). Moreover, the mechanisms underlying the production of false memories are still unclear. Using an experimental episodic memory test with material based on the names of famous people in a procedure derived from the DRM paradigm [Roediger, H. L., III, & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory & Cognition, 21, 803-814], we examined correct and false recall and recognition in 30 young adults, 40 healthy older adults, and 30 patients with AD. Moreover, we evaluated the relationships between false memory performance, correct episodic memory performance, and a set of neuropsychological assessments evaluating the semantic memory and executive functions. The results clearly indicated that correct recall and recognition performance decreased with the subjects' age, but it decreased even more with AD. In addition, semantically related false recalls and false recognitions increased with age but not with dementia. On the contrary, non-semantically related false recalls and false recognitions increased with AD. Finally, the regression analyses showed that executive functions mediated related false memories and episodic memory mediated related and unrelated false memories in aging. Moreover, executive functions predicted related and unrelated false memories in AD, and episodic and semantic memory predicted semantically related and unrelated false memories in AD. In conclusion, the results obtained are consistent with the current constructive models of memory suggesting that false memory creation depends on different cognitive functions and, consequently, that the impairments of these functions influence the production of false memories.

Behavioral Performance and Neural Areas Associated with Memory Processes Contribute to Math and Reading Achievement in 6-year-old Children.

PubMed

Blankenship, Tashauna L; Keith, Kayla; Calkins, Susan D; Bell, Martha Ann

2018-01-01

Associations between working memory and academic achievement (math and reading) are well documented. Surprisingly, little is known of the contributions of episodic memory, segmented into temporal memory (recollection proxy) and item recognition (familiarity proxy), to academic achievement. This is the first study to observe these associations in typically developing 6-year old children. Overlap in neural correlates exists between working memory, episodic memory, and math and reading achievement. We attempted to tease apart the neural contributions of working memory, temporal memory, and item recognition to math and reading achievement. Results suggest that working memory and temporal memory, but not item recognition, are important contributors to both math and reading achievement, and that EEG power during a working memory task contributes to performance on tests of academic achievement.

Frontotemporal Functional Connectivity and Executive Functions Contribute to Episodic Memory Performance

PubMed Central

Blankenship, Tashauna L.; O'Neill, Meagan; Deater-Deckard, Kirby; Diana, Rachel A.; Bell, Martha Ann

2016-01-01

The contributions of hemispheric-specific electrophysiology (electroencephalogram or EEG) and independent executive functions (inhibitory control, working memory, cognitive flexibility) to episodic memory performance were examined using abstract paintings. Right hemisphere frontotemporal functional connectivity during encoding and retrieval, measured via EEG alpha coherence, statistically predicted performance on recency but not recognition judgments for the abstract paintings. Theta coherence, however, did not predict performance. Likewise, cognitive flexibility statistically predicted performance on recency judgments, but not recognition. These findings suggest that recognition and recency operate via separate electrophysiological and executive mechanisms. PMID:27388478

The effects of marital status on episodic and semantic memory in healthy middle-aged and old individuals.

PubMed

Mousavi-Nasab, S-M-Hossein; Kormi-Nouri, Reza; Sundström, Anna; Nilsson, Lars-Göran

2012-02-01

The present study examined the influences of marital status on different episodic and semantic memory tasks. A total of 1882 adult men and women participated in a longitudinal project (Betula) on memory, health and aging. The participants were grouped into two age cohorts, 35-60 and 65-85, and studied over a period of 5 years. Episodic memory tasks concerned recognition and recall, whereas semantic memory tasks concerned knowledge and fluency. The results showed, after controlling for education, some diseases, chronological age and leisure activity as covariates, that there were significant differences between married and single individuals in episodic memory, but not in semantic memory. Married people showed significantly better memory performances than singles in both subsystems of episodic memory, that is, recall and recognition. Also, the rate of decline in episodic memory was significantly larger for singles and widowed than other groups over the 5-year time period in both age groups. The findings demonstrate that the positive relation found between marriage and health can be extended to the relation between marriage and cognitive performance. This effect might be explained by the role played by cognitive stimulation in memory and cognition. © 2011 The Authors. Scandinavian Journal of Psychology © 2011 The Scandinavian Psychological Associations.

Familiar Person Recognition: Is Autonoetic Consciousness More Likely to Accompany Face Recognition Than Voice Recognition?

NASA Astrophysics Data System (ADS)

Barsics, Catherine; Brédart, Serge

2010-11-01

Autonoetic consciousness is a fundamental property of human memory, enabling us to experience mental time travel, to recollect past events with a feeling of self-involvement, and to project ourselves in the future. Autonoetic consciousness is a characteristic of episodic memory. By contrast, awareness of the past associated with a mere feeling of familiarity or knowing relies on noetic consciousness, depending on semantic memory integrity. Present research was aimed at evaluating whether conscious recollection of episodic memories is more likely to occur following the recognition of a familiar face than following the recognition of a familiar voice. Recall of semantic information (biographical information) was also assessed. Previous studies that investigated the recall of biographical information following person recognition used faces and voices of famous people as stimuli. In this study, the participants were presented with personally familiar people's voices and faces, thus avoiding the presence of identity cues in the spoken extracts and allowing a stricter control of frequency exposure with both types of stimuli (voices and faces). In the present study, the rate of retrieved episodic memories, associated with autonoetic awareness, was significantly higher from familiar faces than familiar voices even though the level of overall recognition was similar for both these stimuli domains. The same pattern was observed regarding semantic information retrieval. These results and their implications for current Interactive Activation and Competition person recognition models are discussed.

The episodic engram transformed: Time reduces retrieval-related brain activity but correlates it with memory accuracy.

PubMed

Furman, Orit; Mendelsohn, Avi; Dudai, Yadin

2012-11-15

We took snapshots of human brain activity with fMRI during retrieval of realistic episodic memory over several months. Three groups of participants were scanned during a memory test either hours, weeks, or months after viewing a documentary movie. High recognition accuracy after hours decreased after weeks and remained at similar levels after months. In contrast, BOLD activity in a retrieval-related set of brain areas during correctly remembered events was similar after hours and weeks but significantly declined after months. Despite this reduction, BOLD activity in retrieval-related regions was positively correlated with recognition accuracy only after months. Hippocampal engagement during retrieval remained similar over time during recall but decreased in recognition. Our results are in line with the hypothesis that hippocampus subserves retrieval of real-life episodic memory long after encoding, its engagement being dependent on retrieval demands. Furthermore, our findings suggest that over time episodic engrams are transformed into a parsimonious form capable of supporting accurate retrieval of the crux of events, arguably a critical goal of memory, with only minimal network activation.

Memory and Obstructive Sleep Apnea: A Meta-Analysis

PubMed Central

Wallace, Anna; Bucks, Romola S.

2013-01-01

Study Objectives: To examine episodic memory performance in individuals with obstructive sleep apnea (OSA). Design Meta-analysis was used to synthesize results from individual studies examining the impact of OSA on episodic memory performance. The performance of individuals with OSA was compared to healthy controls or normative data. Participants Forty-two studies were included, comprising 2,294 adults with untreated OSA and 1,364 healthy controls. Studies that recorded information about participants at baseline prior to treatment interventions were included in the analysis. Measurements Participants were assessed with tasks that included a measure of episodic memory: immediate recall, delayed recall, learning, and/or recognition memory. Results: The results of the meta-analyses provide evidence that individuals with OSA are significantly impaired when compared to healthy controls on verbal episodic memory (immediate recall, delayed recall, learning, and recognition) and visuo-spatial episodic memory (immediate and delayed recall), but not visual immediate recall or visuo-spatial learning. When patients were compared to norms, negative effects of OSA were found only in verbal immediate and delayed recall. Conclusions: This meta-analysis contributes to understanding of the nature of episodic memory deficits in individuals with OSA. Impairments to episodic memory are likely to affect the daily functioning of individuals with OSA. Citation Wallace A; Bucks RS. Memory and obstructive sleep apnea: a meta-analysis. SLEEP 2013;36(2):203-220. PMID:23372268

Evidence for a differential contribution of early perceptual and late cognitive processes during encoding to episodic memory impairment in schizophrenia.

PubMed

Green, Amity E; Fitzgerald, Paul B; Johnston, Patrick J; Nathan, Pradeep J; Kulkarni, Jayashri; Croft, Rodney J

2017-08-01

Schizophrenia is characterised by significant episodic memory impairment that is thought to be related to problems with encoding, however the neuro-functional mechanisms underlying these deficits are not well understood. The present study used a subsequent recognition memory paradigm and event-related potentials (ERPs) to investigate temporal aspects of episodic memory encoding deficits in schizophrenia. Electroencephalographic data was recorded in 24 patients and 19 healthy controls whilst participants categorised single words as pleasant/unpleasant. ERPs were generated to subsequently recognised versus unrecognised words on the basis of a forced-choice recognition memory task. Subsequent memory effects were examined with the late positive component (LPP). Group differences in N1, P2, N400 and LPP were examined for words correctly recognised. Patients performed more poorly than controls on the recognition task. During encoding patients had significantly reduced N400 and LPP amplitudes than controls. LPP amplitude correlated with task performance however amplitudes did not differ between patients and controls as a function of subsequent memory. No significant differences in N1 or P2 amplitude or latency were observed. The present results indicate that early sensory processes are intact and dysfunctional higher order cognitive processes during encoding are contributing to episodic memory impairments in schizophrenia.

Aging, recall and recognition: a study on the sensitivity of the University of Southern California Repeatable Episodic Memory Test (USC-REMT).

PubMed

Parker, Elizabeth S; Landau, Susan M; Whipple, Stephen C; Schwartz, Barbara L

2004-05-01

This study examines the sensitivity of the University of Southern California Repeatable Episodic Memory Test (USC-REMT) to the effects of aging in a sample of 112 men and women from 18 to 93 years old. Two new recognition measures, yes-no and forced-choice, were developed to supplement the original USC-REMT which measured only free-recall. Free-recall, yes-no recognition and forced-choice recognition were sensitive to age effects, with free-recall being the most sensitive. The seven recall and recognition lists can be used interchangeably. The data indicate that the USC-REMT is worthy of consideration when there is a need for a brief, screening tool of various memory functions, particularly when there is interest in memory changes over time and repeated assessments.

Selective sex differences in declarative memory.

PubMed

Maitland, Scott B; Herlitz, Agneta; Nyberg, Lars; Bäckman, Lars; Nilsson, Lars-Göran

2004-10-01

Sex invariance of a six-factor, higher order model of declarative memory (two second-order factors: episodic and semantic memory; and four first-order factors: recall, recognition, fluency, and knowledge) was established for 1,796 participants (35-85 years). Metric invariance of first- and second-order factor loadings across sex was demonstrated. At the second-order level, a female advantage was observed for both episodic and semantic memory. At the first-order level, sex differences in episodic memory were apparent for both recall and recognition, whereas the differences in semantic memory were driven by a female superiority in fluency. Additional tests of sex differences in three age groups (35-50, 55-65, and 70-85 years of age) indicated that the female superiority in declarative memory diminished with advancing age. The factor-specific sex differences are discussed in relation to sex differences in hippocampal function.

Hippocampal contributions to recollection in retrograde and anterograde amnesia.

PubMed

Gilboa, Asaf; Winocur, Gordon; Rosenbaum, R Shayna; Poreh, Amir; Gao, Fuqiang; Black, Sandra E; Westmacott, Robyn; Moscovitch, Morris

2006-01-01

Lesions restricted to the hippocampal formation and/or extended hippocampal system (hippocampal formation, fornix, mammillary bodies, and anterior thalamic nuclei) can disrupt conscious recollection in anterograde amnesia, while leaving familiarity-based memory relatively intact. Familiarity may be supported by extra-hippocampal medial temporal lobe (MTL) structures. Within-task dissociations in recognition memory best exemplify this distinction in anterograde amnesia. The authors report for the first time comparable dissociations within recognition memory in retrograde amnesia. An amnesic patient (A.D.) with bilateral fornix and septal nuclei lesions failed to recognize details pertaining to personal past events only when recollection was required, during recognition of episodic details. His intact recognition of generic and semantic details pertaining to the same events was ascribed to intact familiarity processes. Recollective processes in the controls were reflected by asymmetrical Receiver's Operating Characteristic curves, whereas the patient's Receiver's Operating Characteristic was symmetrical, suggesting that his inferior recognition performance on episodic details was reliant on familiarity processes. Anterograde and retrograde memories were equally affected, with no temporal gradient for retrograde memories. By comparison, another amnesic person (K.C.) with extensive MTL damage (involving extra-hippocampal MTL structures in addition to hippocampal and fornix lesions) had very poor recognition and no recollection of either episodic or generic/semantic details. These data suggest that the extended hippocampal system is required to support recollection for both anterograde and retrograde memories, regardless of their age.

Posteromedial hyperactivation during episodic recognition among people with memory decline: findings from the WRAP study

PubMed Central

Nicholas, Christopher R.; Okonkwo, Ozioma C.; Bendlin, Barbara B.; Oh, Jennifer M.; Asthana, Sanjay; Rowley, Howard A.; Hermann, Bruce; Sager, Mark A.

2014-01-01

Episodic memory decline is one of the earliest preclinical symptoms of AD, and has been associated with an upregulation in the BOLD response in the prodromal stage (e.g. MCI) of AD. In a previous study, we observed upregulation in cognitively normal (CN) subjects with subclinical episodic memory decline compared to non-decliners. In light of this finding, we sought to determine if a separate cohort of Decliners will show increased brain activation compared to Stable subjects during episodic memory processing, and determine whether the BOLD effect was influenced by cerebral blood flow (CBF) or gray matter volume (GMV). Individuals were classified as a “Decliner” if scores on the Rey Auditory Verbal Learning Test (RAVLT) consistently fell≥1.5 SD below expected intra- or inter-individual levels. FMRI was used to compare activation during a facial recognition memory task in 90 Stable (age=59.1) and 34 Decliner (age=62.1, SD=5.9) CN middle-aged adults and 10 MCI patients (age=72.1, SD= 9.4). Arterial spin labeling and anatomical T1 MRI were used to measure resting CBF and GMV, respectively. Stables and Decliners performed similarly on the episodic recognition memory task and significantly better than MCI patients. Compared to Stables, Decliners showed increased BOLD signal in the left precuneus on the episodic memory task that was not explained by CBF or GMV, familial AD risk factors, or neuropsychological measures. These findings suggest that subtle changes in the BOLD signal reflecting altered neural function may be a relatively early phenomenon associated with memory decline. PMID:25332108

Recognition memory probes affect what is remembered in schizophrenia.

PubMed

Schwartz, Barbara L; Parker, Elizabeth S; Rosse, Richard B; Deutsch, Stephen I

2009-05-15

Cognitive psychology offers tools to localize the memory processes most vulnerable to disruption in schizophrenia and to identify how patients with schizophrenia best remember. In this research, we used the University of Southern California Repeatable Episodic Memory Test (USC-REMT; Parker, E.S., Landau, S.M., Whipple, S.C., Schwartz, B.L., 2004. Aging, recall, and recognition: A study on the sensitivity of the University of Southern California Repeatable Episodic Memory Test (USC-REMT). Journal of Clinical and Experimental Neuropsychology 26(3), 428-440.) to examine how two different recognition memory probes affect memory performance in patients with schizophrenia and matched controls. Patients with schizophrenia studied equivalent word lists and were tested by yes-no recognition and forced-choice recognition following identical encoding and storage conditions. Compared with controls, patients with schizophrenia were particularly impaired when tested by yes-no recognition relative to forced-choice recognition. Patients had greatest deficits on hits in yes-no recognition but did not exhibit elevated false alarms. The data point to the importance of retrieval processes in schizophrenia, and highlight the need for further research on ways to help patients with schizophrenia access what they have learned.

Priming in Episodic and Semantic Memory.

ERIC Educational Resources Information Center

McKoon, Gail; Ratcliff, Roger

1979-01-01

Four experiments examined priming between newly learned paired associates through two procedures, lexical decision and item recognition. Results argue against a functional separation of the semantic and episodic memory systems. (Author/AM)

Category Specificity in Normal Episodic Learning: Applications to Object Recognition and Category-Specific Agnosia

ERIC Educational Resources Information Center

Bukach, Cindy M.; Bub, Daniel N.; Masson, Michael E. J.; Lindsay, D. Stephen

2004-01-01

Studies of patients with category-specific agnosia (CSA) have given rise to multiple theories of object recognition, most of which assume the existence of a stable, abstract semantic memory system. We applied an episodic view of memory to questions raised by CSA in a series of studies examining normal observers' recall of newly learned attributes…

A SEMantic and EPisodic Memory Test (SEMEP) Developed within the Embodied Cognition Framework: Application to Normal Aging, Alzheimer's Disease and Semantic Dementia.

PubMed

Vallet, Guillaume T; Hudon, Carol; Bier, Nathalie; Macoir, Joël; Versace, Rémy; Simard, Martine

2017-01-01

Embodiment has highlighted the importance of sensory-motor components in cognition. Perception and memory are thus very tightly bound together, and episodic and semantic memories should rely on the same grounded memory traces. Reduced perception should then directly reduce the ability to encode and retrieve an episodic memory, as in normal aging. Multimodal integration deficits, as in Alzheimer's disease, should lead to more severe episodic memory impairment. The present study introduces a new memory test developed to take into account these assumptions. The SEMEP (SEMantic-Episodic) memory test proposes to assess conjointly semantic and episodic knowledge across multiple tasks: semantic matching, naming, free recall, and recognition. The performance of young adults is compared to healthy elderly adults (HE), patients with Alzheimer's disease (AD), and patients with semantic dementia (SD). The results show specific patterns of performance between the groups. HE commit memory errors only for presented but not to be remembered items. AD patients present the worst episodic memory performance associated with intrusion errors (recall or recognition of items never presented). They were the only group to not benefit from a visual isolation (addition of a yellow background), a method known to increase the distinctiveness of the memory traces. Finally, SD patients suffer from the most severe semantic impairment. To conclude, confusion errors are common across all the elderly groups, whereas AD was the only group to exhibit regular intrusion errors and SD patients to show severe semantic impairment.

Mindfulness Enhances Episodic Memory Performance: Evidence from a Multimethod Investigation

PubMed Central

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. PMID:27115491

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

PubMed

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.

Model-Driven Study of Visual Memory

DTIC Science & Technology

2004-12-01

dimensional stimuli (synthetic human faces ) afford important insights into episodic recognition memory. The results were well accommodated by a summed...the unusual properties of the z-transformed ROCS. 15. SUBJECT TERMS Memory, visual memory, computational model, human memory, faces , identity 16...3 Accomplishments/New Findings 3 Work on Objective One: Recognition Memory for Synthetic Faces . 3 Experim ent 1

Evaluating the developmental trajectory of the episodic buffer component of working memory and its relation to word recognition in children.

PubMed

Wang, Shinmin; Allen, Richard J; Lee, Jun Ren; Hsieh, Chia-En

2015-05-01

The creation of temporary bound representation of information from different sources is one of the key abilities attributed to the episodic buffer component of working memory. Whereas the role of working memory in word learning has received substantial attention, very little is known about the link between the development of word recognition skills and the ability to bind information in the episodic buffer of working memory and how it may develop with age. This study examined the performance of Grade 2 children (8 years old), Grade 3 children (9 years old), and young adults on a task designed to measure their ability to bind visual and auditory-verbal information in working memory. Children's performance on this task significantly correlated with their word recognition skills even when chronological age, memory for individual elements, and other possible reading-related factors were taken into account. In addition, clear developmental trajectories were observed, with improvements in the ability to hold temporary bound information in working memory between Grades 2 and 3, and between the child and adult groups, that were independent from memory for the individual elements. These findings suggest that the capacity to temporarily bind novel auditory-verbal information to visual form in working memory is linked to the development of word recognition in children and improves with age. Copyright © 2015 Elsevier Inc. All rights reserved.

Selective verbal recognition memory impairments are associated with atrophy of the language network in non-semantic variants of primary progressive aphasia.

PubMed

Nilakantan, Aneesha S; Voss, Joel L; Weintraub, Sandra; Mesulam, M-Marsel; Rogalski, Emily J

2017-06-01

Primary progressive aphasia (PPA) is clinically defined by an initial loss of language function and preservation of other cognitive abilities, including episodic memory. While PPA primarily affects the left-lateralized perisylvian language network, some clinical neuropsychological tests suggest concurrent initial memory loss. The goal of this study was to test recognition memory of objects and words in the visual and auditory modality to separate language-processing impairments from retentive memory in PPA. Individuals with non-semantic PPA had longer reaction times and higher false alarms for auditory word stimuli compared to visual object stimuli. Moreover, false alarms for auditory word recognition memory were related to cortical thickness within the left inferior frontal gyrus and left temporal pole, while false alarms for visual object recognition memory was related to cortical thickness within the right-temporal pole. This pattern of results suggests that specific vulnerability in processing verbal stimuli can hinder episodic memory in PPA, and provides evidence for differential contributions of the left and right temporal poles in word and object recognition memory. Copyright © 2017 Elsevier Ltd. All rights reserved.

Insights from child development on the relationship between episodic and semantic memory.

PubMed

Robertson, Erin K; Köhler, Stefan

2007-11-05

The present study was motivated by a recent controversy in the neuropsychological literature on semantic dementia as to whether episodic encoding requires semantic processing or whether it can proceed solely based on perceptual processing. We addressed this issue by examining the effect of age-related limitations in semantic competency on episodic memory in 4-6-year-old children (n=67). We administered three different forced-choice recognition memory tests for pictures previously encountered in a single study episode. The tests varied in the degree to which access to semantically encoded information was required at retrieval. Semantic competency predicted recognition performance regardless of whether access to semantic information was required. A direct relation between picture naming at encoding and subsequent recognition was also found for all tests. Our findings emphasize the importance of semantic encoding processes even in retrieval situations that purportedly do not require access to semantic information. They also highlight the importance of testing neuropsychological models of memory in different populations, healthy and brain damaged, at both ends of the developmental continuum.

Episodic Memory and Future Thinking During Early Childhood: Linking the Past and Future

PubMed Central

Cuevas, Kimberly; Rajan, Vinaya; Morasch, Katherine C.; Bell, Martha Ann

2015-01-01

Despite extensive examination of episodic memory and future thinking development, little is known about the concurrent emergence of these capacities during early childhood. In Experiment 1, 3-year-olds participated in an episodic memory hiding task [“what, when, where” (WWW) components] with an episodic future thinking component. In Experiment 2, a group of 4-year-olds (including children from Experiment 1) participated in the same task (different objects and locations), providing the first longitudinal investigation of episodic memory and future thinking. Although children exhibited age-related improvements in recall, recognition, and binding of the WWW episodic memory components, there were no age-related changes in episodic future thinking. At both ages, WWW episodic memory performance was higher than future thinking performance, and episodic future thinking and WWW memory components were unrelated. These findings suggest that the WWW components of episodic memory are potentially less fragile than the future components when assessed in a cognitively demanding task. PMID:25864990

Episodic memory and future thinking during early childhood: Linking the past and future.

PubMed

Cuevas, Kimberly; Rajan, Vinaya; Morasch, Katherine C; Bell, Martha Ann

2015-07-01

Despite extensive examination of episodic memory and future thinking development, little is known about the concurrent emergence of these capacities during early childhood. In Experiment 1, 3-year-olds participated in an episodic memory hiding task ("what, when, where" [WWW] components) with an episodic future thinking component. In Experiment 2, a group of 4-year-olds (including children from Experiment 1) participated in the same task (different objects and locations), providing the first longitudinal investigation of episodic memory and future thinking. Although children exhibited age-related improvements in recall, recognition, and binding of the WWW episodic memory components, there were no age-related changes in episodic future thinking. At both ages, WWW episodic memory performance was higher than future thinking performance, and episodic future thinking and WWW memory components were unrelated. These findings suggest that the WWW components of episodic memory are potentially less fragile than the future components when assessed in a cognitively demanding task. © 2015 Wiley Periodicals, Inc.

Visual Information-Processing in the Perception of Features and Objects

DTIC Science & Technology

1989-01-05

or nodes in a semantic memory network, whereas recall and recognition depend on separate episodic memory traces. In our experiment, we used the same...problem for the account in terms of the separation of episodic from semantic memory , since no pre- existing representations of our line patterns were... semantic memory : amnesic patients were thought to have lost the ability to lay down (or retrieve) episodic traces of autobiographical events, but had

Posteromedial hyperactivation during episodic recognition among people with memory decline: findings from the WRAP study.

PubMed

Nicholas, Christopher R; Okonkwo, Ozioma C; Bendlin, Barbara B; Oh, Jennifer M; Asthana, Sanjay; Rowley, Howard A; Hermann, Bruce; Sager, Mark A; Johnson, Sterling C

2015-12-01

Episodic memory decline is one of the earliest preclinical symptoms of AD, and has been associated with an upregulation in the BOLD response in the prodromal stage (e.g. MCI) of AD. In a previous study, we observed upregulation in cognitively normal (CN) subjects with subclinical episodic memory decline compared to non-decliners. In light of this finding, we sought to determine if a separate cohort of Decliners will show increased brain activation compared to Stable subjects during episodic memory processing, and determine whether the BOLD effect was influenced by cerebral blood flow (CBF) or gray matter volume (GMV). Individuals were classified as a "Decliner" if scores on the Rey Auditory Verbal Learning Test (RAVLT) consistently fell ≥ 1.5 SD below expected intra- or inter-individual levels. FMRI was used to compare activation during a facial recognition memory task in 90 Stable (age = 59.1) and 34 Decliner (age = 62.1, SD = 5.9) CN middle-aged adults and 10 MCI patients (age = 72.1, SD = 9.4). Arterial spin labeling and anatomical T1 MRI were used to measure resting CBF and GMV, respectively. Stables and Decliners performed similarly on the episodic recognition memory task and significantly better than MCI patients. Compared to Stables, Decliners showed increased BOLD signal in the left precuneus on the episodic memory task that was not explained by CBF or GMV, familial AD risk factors, or neuropsychological measures. These findings suggest that subtle changes in the BOLD signal reflecting altered neural function may be a relatively early phenomenon associated with memory decline.

Episodic Short-Term Recognition Requires Encoding into Visual Working Memory: Evidence from Probe Recognition after Letter Report

PubMed Central

Poth, Christian H.; Schneider, Werner X.

2016-01-01

Human vision is organized in discrete processing episodes (e.g., eye fixations or task-steps). Object information must be transmitted across episodes to enable episodic short-term recognition: recognizing whether a current object has been seen in a previous episode. We ask whether episodic short-term recognition presupposes that objects have been encoded into capacity-limited visual working memory (VWM), which retains visual information for report. Alternatively, it could rely on the activation of visual features or categories that occurs before encoding into VWM. We assessed the dependence of episodic short-term recognition on VWM by a new paradigm combining letter report and probe recognition. Participants viewed displays of 10 letters and reported as many as possible after a retention interval (whole report). Next, participants viewed a probe letter and indicated whether it had been one of the 10 letters (probe recognition). In Experiment 1, probe recognition was more accurate for letters that had been encoded into VWM (reported letters) compared with non-encoded letters (non-reported letters). Interestingly, those letters that participants reported in their whole report had been near to one another within the letter displays. This suggests that the encoding into VWM proceeded in a spatially clustered manner. In Experiment 2, participants reported only one of 10 letters (partial report) and probes either referred to this letter, to letters that had been near to it, or far from it. Probe recognition was more accurate for near than for far letters, although none of these letters had to be reported. These findings indicate that episodic short-term recognition is constrained to a small number of simultaneously presented objects that have been encoded into VWM. PMID:27713722

Episodic Short-Term Recognition Requires Encoding into Visual Working Memory: Evidence from Probe Recognition after Letter Report.

PubMed

Poth, Christian H; Schneider, Werner X

2016-01-01

Human vision is organized in discrete processing episodes (e.g., eye fixations or task-steps). Object information must be transmitted across episodes to enable episodic short-term recognition: recognizing whether a current object has been seen in a previous episode. We ask whether episodic short-term recognition presupposes that objects have been encoded into capacity-limited visual working memory (VWM), which retains visual information for report. Alternatively, it could rely on the activation of visual features or categories that occurs before encoding into VWM. We assessed the dependence of episodic short-term recognition on VWM by a new paradigm combining letter report and probe recognition. Participants viewed displays of 10 letters and reported as many as possible after a retention interval (whole report). Next, participants viewed a probe letter and indicated whether it had been one of the 10 letters (probe recognition). In Experiment 1, probe recognition was more accurate for letters that had been encoded into VWM (reported letters) compared with non-encoded letters (non-reported letters). Interestingly, those letters that participants reported in their whole report had been near to one another within the letter displays. This suggests that the encoding into VWM proceeded in a spatially clustered manner. In Experiment 2, participants reported only one of 10 letters (partial report) and probes either referred to this letter, to letters that had been near to it, or far from it. Probe recognition was more accurate for near than for far letters, although none of these letters had to be reported. These findings indicate that episodic short-term recognition is constrained to a small number of simultaneously presented objects that have been encoded into VWM.

Different Ways to Cue a Coherent Memory System: A Theory for Episodic, Semantic, and Procedural Tasks.

ERIC Educational Resources Information Center

Humphreys, Michael S.; And Others

1989-01-01

An associative theory of memory is proposed to serve as a counterexample to claims that dissociations among episodic, semantic, and procedural memory tasks necessitate separate memory systems. The theory is based on task analyses of matching (recognition and familiarity judgments), retrieval (cued recall), and production (free association). (TJH)

Episodic Memory and Regional Atrophy in Frontotemporal Lobar Degeneration

PubMed Central

Söderlund, Hedvig; Black, Sandra E.; Miller, Bruce L.; Freedman, Morris; Levine, Brian

2008-01-01

It has been unclear to what extent memory is affected in frontotemporal lobar degeneration (FTLD). Since patients usually have atrophy in regions implicated in memory function, the frontal and/or temporal lobes, one would expect some memory impairment, and that the degree of atrophy in these regions would be inversely related to memory function. The purposes of this study were 1) to assess episodic memory function in FTLD, and more specifically patients' ability to episodically re-experience an event, and determine its source; 2) to examine whether memory performance is related to quantified regional brain atrophy. FTLD patients (n=18) and healthy comparison subjects (n=14) were assessed with cued recall, recognition, “remember/know” (self-reported re-experiencing) and source recall, at 30 min and 24 hr after encoding. Regional gray matter volumes were assessed with high resolution structural MRI concurrently to testing. Patients performed worse than comparison subjects on all memory measures. Gray matter volume in the left medial temporal lobe was positively correlated with recognition, re-experiencing, and source recall. Gray matter volume in the left posterior temporal lobe correlated significantly with recognition, at 30 min and 24 hr, and with source recall at 30 min. Estimated familiarity at 30 min was positively correlated with gray matter volume in the left inferior parietal lobe. In summary, episodic memory deficits in FTLD may be more common than previously thought, particularly in patients with left medial and posterior temporal atrophy. PMID:17888461

A Potential Spatial Working Memory Training Task to Improve Both Episodic Memory and Fluid Intelligence

PubMed Central

Rudebeck, Sarah R.; Bor, Daniel; Ormond, Angharad; O’Reilly, Jill X.; Lee, Andy C. H.

2012-01-01

One current challenge in cognitive training is to create a training regime that benefits multiple cognitive domains, including episodic memory, without relying on a large battery of tasks, which can be time-consuming and difficult to learn. By giving careful consideration to the neural correlates underlying episodic and working memory, we devised a computerized working memory training task in which neurologically healthy participants were required to monitor and detect repetitions in two streams of spatial information (spatial location and scene identity) presented simultaneously (i.e. a dual n-back paradigm). Participants’ episodic memory abilities were assessed before and after training using two object and scene recognition memory tasks incorporating memory confidence judgments. Furthermore, to determine the generalizability of the effects of training, we also assessed fluid intelligence using a matrix reasoning task. By examining the difference between pre- and post-training performance (i.e. gain scores), we found that the trainers, compared to non-trainers, exhibited a significant improvement in fluid intelligence after 20 days. Interestingly, pre-training fluid intelligence performance, but not training task improvement, was a significant predictor of post-training fluid intelligence improvement, with lower pre-training fluid intelligence associated with greater post-training gain. Crucially, trainers who improved the most on the training task also showed an improvement in recognition memory as captured by d-prime scores and estimates of recollection and familiarity memory. Training task improvement was a significant predictor of gains in recognition and familiarity memory performance, with greater training improvement leading to more marked gains. In contrast, lower pre-training recollection memory scores, and not training task improvement, led to greater recollection memory performance after training. Our findings demonstrate that practice on a single working memory task can potentially improve aspects of both episodic memory and fluid intelligence, and that an extensive training regime with multiple tasks may not be necessary. PMID:23209740

A potential spatial working memory training task to improve both episodic memory and fluid intelligence.

PubMed

Rudebeck, Sarah R; Bor, Daniel; Ormond, Angharad; O'Reilly, Jill X; Lee, Andy C H

2012-01-01

One current challenge in cognitive training is to create a training regime that benefits multiple cognitive domains, including episodic memory, without relying on a large battery of tasks, which can be time-consuming and difficult to learn. By giving careful consideration to the neural correlates underlying episodic and working memory, we devised a computerized working memory training task in which neurologically healthy participants were required to monitor and detect repetitions in two streams of spatial information (spatial location and scene identity) presented simultaneously (i.e. a dual n-back paradigm). Participants' episodic memory abilities were assessed before and after training using two object and scene recognition memory tasks incorporating memory confidence judgments. Furthermore, to determine the generalizability of the effects of training, we also assessed fluid intelligence using a matrix reasoning task. By examining the difference between pre- and post-training performance (i.e. gain scores), we found that the trainers, compared to non-trainers, exhibited a significant improvement in fluid intelligence after 20 days. Interestingly, pre-training fluid intelligence performance, but not training task improvement, was a significant predictor of post-training fluid intelligence improvement, with lower pre-training fluid intelligence associated with greater post-training gain. Crucially, trainers who improved the most on the training task also showed an improvement in recognition memory as captured by d-prime scores and estimates of recollection and familiarity memory. Training task improvement was a significant predictor of gains in recognition and familiarity memory performance, with greater training improvement leading to more marked gains. In contrast, lower pre-training recollection memory scores, and not training task improvement, led to greater recollection memory performance after training. Our findings demonstrate that practice on a single working memory task can potentially improve aspects of both episodic memory and fluid intelligence, and that an extensive training regime with multiple tasks may not be necessary.

Forms Of Memory For Representation Of Visual Objects

DTIC Science & Technology

1991-02-14

description system that functions independently of the episodic memory system that is damaged in amnesia and supports explicit remembering. Miscellaneous...well as semantic and functional information about an object, are preserved in the episodic system. 4. Priming and recognition of depth-cued, 3D objects A...requirement should serve to enhance an object’s distinctiveness in episodic memory . We also predicted robust priming for symmetric objects; this is because

Elements of episodic-like memory in animal models.

PubMed

Crystal, Jonathon D

2009-03-01

Representations of unique events from one's past constitute the content of episodic memories. A number of studies with non-human animals have revealed that animals remember specific episodes from their past (referred to as episodic-like memory). The development of animal models of memory holds enormous potential for gaining insight into the biological bases of human memory. Specifically, given the extensive knowledge of the rodent brain, the development of rodent models of episodic memory would open new opportunities to explore the neuroanatomical, neurochemical, neurophysiological, and molecular mechanisms of memory. Development of such animal models holds enormous potential for studying functional changes in episodic memory in animal models of Alzheimer's disease, amnesia, and other human memory pathologies. This article reviews several approaches that have been used to assess episodic-like memory in animals. The approaches reviewed include the discrimination of what, where, and when in a radial arm maze, dissociation of recollection and familiarity, object recognition, binding, unexpected questions, and anticipation of a reproductive state. The diversity of approaches may promote the development of converging lines of evidence on the difficult problem of assessing episodic-like memory in animals.

Selective deficits in episodic feeling of knowing in ageing: a novel use of the general knowledge task.

PubMed

Morson, Suzannah M; Moulin, Chris J A; Souchay, Céline

2015-05-01

Failure to recall an item from memory can be accompanied by the subjective experience that the item is known but currently unavailable for report. The feeling of knowing (FOK) task allows measurement of the predictive accuracy of this reflective judgement. Young and older adults were asked to provide answers to general knowledge questions both prior to and after learning, thus measuring both semantic and episodic memory for the items. FOK judgements were made at each stage for all unrecalled responses, providing a measure of predictive accuracy for semantic and episodic knowledge. Results demonstrated a selective effect of age on episodic FOK resolution, with older adults found to have impaired episodic FOK accuracy while semantic FOK accuracy remained intact. Although recall and recognition measures of episodic memory are equivalent between the two age groups, older adults may have been unable to access contextual details on which to base their FOK judgements. The results suggest that older adults are not able to accurately predict future recognition of unrecalled episodic information, and consequently may have difficulties in monitoring recently encoded memories. Copyright © 2015. Published by Elsevier B.V.

Memantine improves attention and episodic memory in Parkinson's disease dementia and dementia with Lewy bodies.

PubMed

Wesnes, Keith A; Aarsland, Dag; Ballard, Clive; Londos, Elisabet

2015-01-01

In both dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD), attentional dysfunction is a core clinical feature together with disrupted episodic memory. This study evaluated the cognitive effects of memantine in DLB and PDD using automated tests of attention and episodic memory. A randomised double-blind, placebo-controlled, 24-week three centre trial of memantine (20 mg/day) was conducted in which tests of attention (simple and choice reaction time) and word recognition (immediate and delayed) from the CDR System were administered prior to dosing and again at 12 and 24 weeks. Although other results from this study have been published, the data from the CDR System tests were not included and are presented here for the first time. Data were available for 51 patients (21 DLB and 30 PDD). In both populations, memantine produced statistically significant medium to large effect sized improvements to choice reaction time, immediate and delayed word recognition. These are the first substantial improvements on cognitive tests of attention and episodic recognition memory identified with memantine in either DLB or PDD. Copyright © 2014 John Wiley & Sons, Ltd.

Recollection and Familiarity in Recognition Memory: Evidence from ROC Curves

ERIC Educational Resources Information Center

Heathcote, Andrew; Raymond, Frances; Dunn, John

2006-01-01

Does recognition memory rely on discrete recollection, continuous evidence, or both? Is continuous evidence sensitive to only the recency and duration of study (familiarity), or is it also sensitive to details of the study episode? Dual process theories assume recognition is based on recollection and familiarity, with only recollection providing…

Feature binding and attention in working memory: a resolution of previous contradictory findings.

PubMed

Allen, Richard J; Hitch, Graham J; Mate, Judit; Baddeley, Alan D

2012-01-01

We aimed to resolve an apparent contradiction between previous experiments from different laboratories, using dual-task methodology to compare effects of a concurrent executive load on immediate recognition memory for colours or shapes of items or their colour-shape combinations. Results of two experiments confirmed previous evidence that an irrelevant attentional load interferes equally with memory for features and memory for feature bindings. Detailed analyses suggested that previous contradictory evidence arose from limitations in the way recognition memory was measured. The present findings are inconsistent with an earlier suggestion that feature binding takes place within a multimodal episodic buffer Baddeley, ( 2000 ) and support a subsequent account in which binding takes place automatically prior to information entering the episodic buffer Baddeley, Allen, & Hitch, ( 2011 ). Methodologically, the results suggest that different measures of recognition memory performance (A', d', corrected recognition) give a converging picture of main effects, but are less consistent in detecting interactions. We suggest that this limitation on the reliability of measuring recognition should be taken into account in future research so as to avoid problems of replication that turn out to be more apparent than real.

Interidentity amnesia for neutral, episodic information in dissociative identity disorder.

PubMed

Huntjens, Rafaële J C; Postma, Albert; Peters, Madelon L; Woertman, Liesbeth; van der Hart, Onno

2003-05-01

Interidentity amnesia is considered a hallmark of dissociative identity disorder (DID) in clinical practice. In this study, objective methods of testing episodic memory transfer between identities were used. Tests of both recall (interference paradigm) and recognition were used. A sample of 31 DID patients was included. Additionally, 50 control subjects participated, half functioning as normal controls and the other half simulating interidentity amnesia. Twenty-one patients subjectively reported complete one-way amnesia for the learning episode. However, objectively, neither recall nor recognition scores of patients were different from those of normal controls. It is suggested that clinical models of amnesia in DID may be specified to exclude episodic memory impairments for emotionally neutral material.

Females scan more than males: a potential mechanism for sex differences in recognition memory.

PubMed

Heisz, Jennifer J; Pottruff, Molly M; Shore, David I

2013-07-01

Recognition-memory tests reveal individual differences in episodic memory; however, by themselves, these tests provide little information regarding the stage (or stages) in memory processing at which differences are manifested. We used eye-tracking technology, together with a recognition paradigm, to achieve a more detailed analysis of visual processing during encoding and retrieval. Although this approach may be useful for assessing differences in memory across many different populations, we focused on sex differences in face memory. Females outperformed males on recognition-memory tests, and this advantage was directly related to females' scanning behavior at encoding. Moreover, additional exposures to the faces reduced sex differences in face recognition, which suggests that males may be able to improve their recognition memory by extracting more information at encoding through increased scanning. A strategy of increased scanning at encoding may prove to be a simple way to enhance memory performance in other populations with memory impairment.

Older adults encode--but do not always use--perceptual details: intentional versus unintentional effects of detail on memory judgments.

PubMed

Koutstaal, Wilma

2003-03-01

Investigations of memory deficits in older individuals have concentrated on their increased likelihood of forgetting events or details of events that were actually encountered (errors of omission). However, mounting evidence demonstrates that normal cognitive aging also is associated with an increased propensity for errors of commission--shown in false alarms or false recognition. The present study examined the origins of this age difference. Older and younger adults each performed three types of memory tasks in which details of encountered items might influence performance. Although older adults showed greater false recognition of related lures on a standard (identical) old/new episodic recognition task, older and younger adults showed parallel effects of detail on repetition priming and meaning-based episodic recognition (decreased priming and decreased meaning-based recognition for different relative to same exemplars). The results suggest that the older adults encoded details but used them less effectively than the younger adults in the recognition context requiring their deliberate, controlled use.

Global similarity predicts dissociation of classification and recognition: evidence questioning the implicit-explicit learning distinction in amnesia.

PubMed

Jamieson, Randall K; Holmes, Signy; Mewhort, D J K

2010-11-01

Dissociation of classification and recognition in amnesia is widely taken to imply 2 functional systems: an implicit procedural-learning system that is spared in amnesia and an explicit episodic-learning system that is compromised. We argue that both tasks reflect the global similarity of probes to memory. In classification, subjects sort unstudied grammatical exemplars from lures, whereas in recognition, they sort studied grammatical exemplars from lures. Hence, global similarity is necessarily greater in recognition than in classification. Moreover, a grammatical exemplar's similarity to studied exemplars is a nonlinear function of the integrity of the data in memory. Assuming that data integrity is better for control subjects than for subjects with amnesia, the nonlinear relation combined with the advantage for recognition over classification predicts the dissociation of recognition and classification. To illustrate the dissociation of recognition and classification in healthy undergraduates, we manipulated study time to vary the integrity of the data in memory and brought the dissociation under experimental control. We argue that the dissociation reflects a general cost in memory rather than a selective impairment of separate procedural and episodic systems. (c) 2010 APA, all rights reserved

Haloperidol increases false recognition memory of thematically related pictures in healthy volunteers.

PubMed

Guarnieri, Regina V; Buratto, Luciano G; Gomes, Carlos F A; Ribeiro, Rafaela L; de Souza, Altay A Lino; Stein, Lilian M; Galduróz, José C; Bueno, Orlando F A

2017-01-01

Dopamine can modulate long-term episodic memory. Its potential role on the generation of false memories, however, is less well known. In a randomized, double-blind, placebo-controlled experiment, 24 young healthy volunteers ingested a 4-mg oral dose of haloperidol, a dopamine D 2 -receptor antagonist, or placebo, before taking part in a recognition memory task. Haloperidol was active during both study and test phases of the experiment. Participants in the haloperidol group produced more false recognition responses than those in the placebo group, despite similar levels of correct recognition. These findings show that dopamine blockade in healthy volunteers can specifically increase false recognition memory. Copyright © 2016 John Wiley & Sons, Ltd.

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

PubMed

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.

Release from output interference in recognition memory: A test of the attention hypothesis.

PubMed

Criss, Amy H; Salomão, Cristina; Malmberg, Kenneth J; Aue, William; Kılıç, Aslı; Claridge, MarkAvery

2018-05-01

Retrieval results in both costs and benefits to episodic memory. Output interference (OI) refers to the finding that episodic memory accuracy decreases with increasing test trials. Release from OI is the restoration of original accuracy at some point during the test. For example, a release from OI in recognition memory testing occurs when the semantic similarity between stimuli decreases midway through testing, suggesting that item representations stored on early trials cause interference on tests occurring on later trials to the extent that the earlier items share features with the latter items. In two recognition memory experiments, we demonstrate release from OI for words and faces. We also test whether release from OI is the result of interference or is due to a boost in attention caused by reorienting to a novel stimulus type. A test for the foils presented during the initial test list supports the interference account of OI. Implications for models of memory are discussed.

The Episodic Engram Transformed: Time Reduces Retrieval-Related Brain Activity but Correlates It with Memory Accuracy

ERIC Educational Resources Information Center

Furman, Orit; Mendelsohn, Avi; Dudai, Yadin

2012-01-01

We took snapshots of human brain activity with fMRI during retrieval of realistic episodic memory over several months. Three groups of participants were scanned during a memory test either hours, weeks, or months after viewing a documentary movie. High recognition accuracy after hours decreased after weeks and remained at similar levels after…

Flynn effects on sub-factors of episodic and semantic memory: parallel gains over time and the same set of determining factors.

PubMed

Rönnlund, Michael; Nilsson, Lars-Göran

2009-09-01

The study examined the extent to which time-related gains in cognitive performance, so-called Flynn effects, generalize across sub-factors of episodic memory (recall and recognition) and semantic memory (knowledge and fluency). We conducted time-sequential analyses of data drawn from the Betula prospective cohort study, involving four age-matched samples (35-80 years; N=2996) tested on the same battery of memory tasks on either of four occasions (1989, 1995, 1999, and 2004). The results demonstrate substantial time-related improvements on recall and recognition as well as on fluency and knowledge, with a trend of larger gains on semantic as compared with episodic memory [Rönnlund, M., & Nilsson, L. -G. (2008). The magnitude, generality, and determinants of Flynn effects on forms of declarative memory: Time-sequential analyses of data from a Swedish cohort study. Intelligence], but highly similar gains across the sub-factors. Finally, the association with markers of environmental change was similar, with evidence that historical increases in quantity of schooling was a main driving force behind the gains, both on the episodic and semantic sub-factors. The results obtained are discussed in terms of brain regions involved.

A unified framework for the functional organization of the medial temporal lobes and the phenomenology of episodic memory.

PubMed

Ranganath, Charan

2010-11-01

There is currently an intense debate about the nature of recognition memory and about the roles of medial temporal lobe subregions in recognition memory processes. At a larger level, this debate has been about whether it is appropriate to propose unified theories to explain memory at neural, functional, and phenomenological levels of analysis. Here, I review findings from physiology, functional imaging, and lesion studies in humans, monkeys, and rodents relevant to the roles of medial temporal lobe subregions in recognition memory, as well as in short-term memory and perception. The results from these studies are consistent with the idea that there is functional heterogeneity in the medial temporal lobes, although the differences among medial temporal lobe subregions do not precisely correspond to different types of memory tasks, cognitive processes, or states of awareness. Instead, the evidence is consistent with the idea that medial temporal lobe subregions differ in terms of the kind of information they process and represent, and that these regions collectively support episodic memory by binding item and context information. © 2010 Wiley-Liss, Inc.

The effects of road traffic and aircraft noise exposure on children's episodic memory: the RANCH project.

PubMed

Matheson, Mark; Clark, Charlotte; Martin, Rocio; van Kempen, Elise; Haines, Mary; Barrio, Isabel Lopez; Hygge, Staffan; Stansfeld, Stephen

2010-01-01

Previous studies have found that chronic exposure to aircraft noise has a negative effect on children's performance on tests of episodic memory. The present study extended the design of earlier studies in three ways: firstly, by examining the effects of two noise sources, aircraft and road traffic, secondly, by examining exposure-effect relationships, and thirdly, by carrying out parallel field studies in three European countries, allowing cross-country comparisons to be made. A total of 2844 children aged between 8 years 10 months and 12 years 10 months (mean age 10 years 6 months) completed classroom-based tests of cued recall, recognition memory and prospective memory. Questionnaires were also completed by the children and their parents in order to provide information about socioeconomic context. Multilevel modeling analysis revealed aircraft noise to be associated with an impairment of recognition memory in a linear exposure-effect relationship. The analysis also found road traffic noise to be associated with improved performance on cued recall in a linear exposure-effect relationship. No significant association was found between exposure to aircraft noise and cued recall or prospective memory. Likewise, no significant association was found between road traffic noise and recognition or prospective memory. Taken together, these findings indicate that exposure to aircraft noise and road traffic noise can impact on certain aspects of children's episodic memory.

Examination of the bidirectional influences of leisure activity and memory in old people: a dissociative effect on episodic memory.

PubMed

Mousavi-Nasab, S-M-Hossein; Kormi-Nouri, Reza; Nilsson, Lars-Göran

2014-08-01

The present study examined the relationships between different types of social and cognitive activities and different types of episodic and semantic memory. A total of 794 adult men and women from five age cohorts (aged 65-85 at baseline), participating in the longitudinal Betula project on ageing, memory, and health, were included in the study. The participants were studied over 10 years (1995-2005) in three waves. Recognition and recall were used as episodic memory tasks, and knowledge and verbal fluency as semantic memory tasks. The results, after controlling for age, gender, education, and some diseases, including heart disease and hypertension, as covariates, showed unidirectional effects of social activity on episodic memory on all test occasions (β = .10). Also, episodic memory predicted change in cognitive activity for all test waves (β = .21-.22). Findings suggest that social activity can be seen as protective factor against memory decline. It also seems that episodic memory performance is a predictor of cognitive activity in old people. However, the opposite direction does not hold true. © 2013 The British Psychological Society.

The electrophysiological correlates of recent and remote recollection.

PubMed

Roberts, J S; Tsivilis, D; Mayes, A R

2013-09-01

Research using event related potentials (ERPs) to explore recognition memory has linked late parietal old/new effects to the recollection of episodic information. In the vast majority of these studies, the retrieval phase immediately follows encoding and consequently, very little is known about the ERP correlates of long term recollection. This is despite the fact that in other areas of the memory literature there is considerable interest in consolidation theories and the way episodic memory changes over time. The present study explored the idea that consolidation and forgetting processes operating over a moderate retention interval can alter the ERP markers of recollection memory. A remember/know test probed memory for stimuli studied either 15 minutes (recent memory) or 1 week (remote memory) prior to the test phase. Results revealed an attenuated late parietal effect for remote compared to recent remember responses, a finding that remained significant even when these recognition judgments were matched for reaction time. Experiments 2a and 2b identified characteristic differences between recent and remote recognition at the behavioural level. The 1 week delay produced an overall decline in recognition confidence and a dramatic loss of episodic detail. These behavioural changes are thought to underlie the ERP effects reported in the first experiment. The results highlight that although the neural basis of memory may exhibit significant changes as the length of the retention interval increases, it is important to consider the extent to which this is a direct effect of time or an indirect effect due to changes in memory quality, such as the amount of detail that can be recollected. © 2013 Elsevier Ltd. All rights reserved.

The Doors and People Test: The Effect of Frontal Lobe Lesions on Recall and Recognition Memory Performance

PubMed Central

2016-01-01

Objective: Memory deficits in patients with frontal lobe lesions are most apparent on free recall tasks that require the selection, initiation, and implementation of retrieval strategies. The effect of frontal lesions on recognition memory performance is less clear with some studies reporting recognition memory impairments but others not. The majority of these studies do not directly compare recall and recognition within the same group of frontal patients, assessing only recall or recognition memory performance. Other studies that do compare recall and recognition in the same frontal group do not consider recall or recognition tests that are comparable for difficulty. Recognition memory impairments may not be reported because recognition memory tasks are less demanding. Method: This study aimed to investigate recall and recognition impairments in the same group of 47 frontal patients and 78 healthy controls. The Doors and People Test was administered as a neuropsychological test of memory as it assesses both verbal and visual recall and recognition using subtests that are matched for difficulty. Results: Significant verbal and visual recall and recognition impairments were found in the frontal patients. Conclusion: These results demonstrate that when frontal patients are assessed on recall and recognition memory tests of comparable difficulty, memory impairments are found on both types of episodic memory test. PMID:26752123

The Doors and People Test: The effect of frontal lobe lesions on recall and recognition memory performance.

PubMed

MacPherson, Sarah E; Turner, Martha S; Bozzali, Marco; Cipolotti, Lisa; Shallice, Tim

2016-03-01

Memory deficits in patients with frontal lobe lesions are most apparent on free recall tasks that require the selection, initiation, and implementation of retrieval strategies. The effect of frontal lesions on recognition memory performance is less clear with some studies reporting recognition memory impairments but others not. The majority of these studies do not directly compare recall and recognition within the same group of frontal patients, assessing only recall or recognition memory performance. Other studies that do compare recall and recognition in the same frontal group do not consider recall or recognition tests that are comparable for difficulty. Recognition memory impairments may not be reported because recognition memory tasks are less demanding. This study aimed to investigate recall and recognition impairments in the same group of 47 frontal patients and 78 healthy controls. The Doors and People Test was administered as a neuropsychological test of memory as it assesses both verbal and visual recall and recognition using subtests that are matched for difficulty. Significant verbal and visual recall and recognition impairments were found in the frontal patients. These results demonstrate that when frontal patients are assessed on recall and recognition memory tests of comparable difficulty, memory impairments are found on both types of episodic memory test. (c) 2016 APA, all rights reserved).

[Building and validation of a test evaluating verbal recognition memory: The Forty test (f40)].

PubMed

Marqué, A; Hommet, C; Constans, T; Perrier, D; Bardet, F; Chaput, M; Mondon, K

2011-04-01

Neuropsychologic evaluation is a primordial diagnostic tool. Numerous tests explore episodic memory but few tests exist to assess incidental verbal episodic memory or verbal recognition memory. This memory is however impaired early in certain neurodegenerative diseases such as Alzheimer's disease. Our objective was to create a test sensitive and specific to this cognitive dysfunction. Our test was performed by 33 healthy volunteers and 51 patients (19 with idiopathic Parkinson's disease, 16 with Alzheimer's disease at the prodromal stage and 16 with Alzheimer's disease). Independently of age, education level and global cognitive impairment, the young and old healthy volunteers and the patients with idiopathic Parkinson's disease displayed results significantly better than the group of Alzheimer's disease at the prodromal stage and Alzheimer's disease patients. Our test appears to be sensitive to dysfunction of verbal recognition memory. A score of 30/40 or less on the Forty test discriminates 91% of subjects with a cortical pattern of memory. This test could be recommended for clinical neuropsychological practice. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Pushing typists back on the learning curve: Memory chunking improves retrieval of prior typing episodes.

PubMed

Yamaguchi, Motonori; Randle, James M; Wilson, Thomas L; Logan, Gordon D

2017-09-01

Hierarchical control of skilled performance depends on chunking of several lower-level units into a single higher-level unit. The present study examined the relationship between chunking and recognition of trained materials in the context of typewriting. In 3 experiments, participants were trained with typing nonwords and were later tested on their recognition of the trained materials. In Experiment 1, participants typed the same words or nonwords in 5 consecutive trials while performing a concurrent memory task. In Experiment 2, participants typed the materials with lags between repetitions without a concurrent memory task. In both experiments, recognition of typing materials was associated with better chunking of the materials. Experiment 3 used the remember-know procedure to test the recollection and familiarity components of recognition. Remember judgments were associated with better chunking than know judgments or nonrecognition. These results indicate that chunking is associated with explicit recollection of prior typing episodes. The relevance of the existing memory models to chunking in typewriting was considered, and it is proposed that memory chunking improves retrieval of trained typing materials by integrating contextual cues into the memory traces. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

[Early episodic memory impairments in Alzheimer's disease].

PubMed

Ergis, A-M; Eusop-Roussel, E

2008-05-01

Patients with Alzheimer's disease (AD) show early episodic memory impairments. Such deficits reflect specific impairments affecting one or several stages of encoding, storage and retrieval processes. However, AD patients not only have great difficulty retrieving memories and information but also suffer from distortions of memory, as intrusions and false recognitions. Intrusions can be defined as the unintentional recall of inappropriate information in a laboratory-learning tasks such as word-list recall and story recall. False recognition refers to the erroneous recognition of information that was not previously presented. The first objective of this review is to present studies from the literature that allowed a better understanding of the nature of episodic memory deficits in AD, and to examine recent research on false memories. The second part of this review is aimed at presenting recent research conducted on prospective memory (PM) in Alzheimer's disease. Prospective memory situations involve forming intentions and then realizing those intentions at some appropriate time in the future. Everyday examples of prospective memory include remembering to buy bread on the way home from work, remembering to give friends a message upon next encountering them, and remembering to take medication. Patients suffering from AD show difficulties in performing prospective tasks in daily life, according to the complaints of their care givers, and these difficulties are massively present at the first stages of the disease. Nevertheless, very few studies have been dedicated to this subject, although the evaluation of PM could be helpful for the early diagnosis of AD.

Flynn Effects on Sub-Factors of Episodic and Semantic Memory: Parallel Gains over Time and the Same Set of Determining Factors

ERIC Educational Resources Information Center

Ronnlund, Michael; Nilsson, Lars-Goran.

2009-01-01

The study examined the extent to which time-related gains in cognitive performance, so-called Flynn effects, generalize across sub-factors of episodic memory (recall and recognition) and semantic memory (knowledge and fluency). We conducted time-sequential analyses of data drawn from the Betula prospective cohort study, involving four age-matched…

A review on the neural bases of episodic odor memory: from laboratory-based to autobiographical approaches

PubMed Central

Saive, Anne-Lise; Royet, Jean-Pierre; Plailly, Jane

2014-01-01

Odors are powerful cues that trigger episodic memories. However, in light of the amount of behavioral data describing the characteristics of episodic odor memory, the paucity of information available on the neural substrates of this function is startling. Furthermore, the diversity of experimental paradigms complicates the identification of a generic episodic odor memory network. We conduct a systematic review of the literature depicting the current state of the neural correlates of episodic odor memory in healthy humans by placing a focus on the experimental approaches. Functional neuroimaging data are introduced by a brief characterization of the memory processes investigated. We present and discuss laboratory-based approaches, such as odor recognition and odor associative memory, and autobiographical approaches, such as the evaluation of odor familiarity and odor-evoked autobiographical memory. We then suggest the development of new laboratory-ecological approaches allowing for the controlled encoding and retrieval of specific multidimensional events that could open up new prospects for the comprehension of episodic odor memory and its neural underpinnings. While large conceptual differences distinguish experimental approaches, the overview of the functional neuroimaging findings suggests relatively stable neural correlates of episodic odor memory. PMID:25071494

Evidence for the contribution of a threshold retrieval process to semantic memory.

PubMed

Kempnich, Maria; Urquhart, Josephine A; O'Connor, Akira R; Moulin, Chris J A

2017-10-01

It is widely held that episodic retrieval can recruit two processes: a threshold context retrieval process (recollection) and a continuous signal strength process (familiarity). Conversely the processes recruited during semantic retrieval are less well specified. We developed a semantic task analogous to single-item episodic recognition to interrogate semantic recognition receiver-operating characteristics (ROCs) for a marker of a threshold retrieval process. We fitted observed ROC points to three signal detection models: two models typically used in episodic recognition (unequal variance and dual-process signal detection models) and a novel dual-process recollect-to-reject (DP-RR) signal detection model that allows a threshold recollection process to aid both target identification and lure rejection. Given the nature of most semantic questions, we anticipated the DP-RR model would best fit the semantic task data. Experiment 1 (506 participants) provided evidence for a threshold retrieval process in semantic memory, with overall best fits to the DP-RR model. Experiment 2 (316 participants) found within-subjects estimates of episodic and semantic threshold retrieval to be uncorrelated. Our findings add weight to the proposal that semantic and episodic memory are served by similar dual-process retrieval systems, though the relationship between the two threshold processes needs to be more fully elucidated.

Olfactory memory in the old and very old: relations to episodic and semantic memory and APOE genotype.

PubMed

Larsson, Maria; Hedner, Margareta; Papenberg, Goran; Seubert, Janina; Bäckman, Lars; Laukka, Erika J

2016-02-01

The neuroanatomical organization that underlies olfactory memory is different from that of other memory types. The present work examines olfactory memory in an elderly population-based sample (Swedish National Study on Aging and Care in Kungsholmen) aged 60-100 years (n = 2280). We used structural equation modeling to investigate whether olfactory memory in old age is best conceptualized as a distinct category, differentiated from episodic and semantic memory. Further, potential olfactory dedifferentiation and genetic associations (APOE) to olfactory function in late senescence were investigated. Results are in support of a 3-factor solution where olfactory memory, as indexed by episodic odor recognition and odor identification, is modeled separately from episodic and semantic memory for visual and verbal information. Increasing age was associated with poorer olfactory memory performance, and observed age-related deficits were further exacerbated for carriers of the APOE ε4 allele; these effects tended to be larger for olfactory memory compared to episodic and semantic memory pertaining to other sensory systems (vision, auditory). Finally, stronger correlations between olfactory and episodic memory, indicating dedifferentiation, were observed in the older age groups. Copyright © 2016 Elsevier Inc. All rights reserved.

Semantic and episodic memory of music are subserved by distinct neural networks.

PubMed

Platel, Hervé; Baron, Jean-Claude; Desgranges, Béatrice; Bernard, Frédéric; Eustache, Francis

2003-09-01

Numerous functional imaging studies have shown that retrieval from semantic and episodic memory is subserved by distinct neural networks. However, these results were essentially obtained with verbal and visuospatial material. The aim of this work was to determine the neural substrates underlying the semantic and episodic components of music using familiar and nonfamiliar melodic tunes. To study musical semantic memory, we designed a task in which the instruction was to judge whether or not the musical extract was felt as "familiar." To study musical episodic memory, we constructed two delayed recognition tasks, one containing only familiar and the other only nonfamiliar items. For each recognition task, half of the extracts (targets) were presented in the prior semantic task. The episodic and semantic tasks were to be contrasted by a comparison to two perceptive control tasks and to one another. Cerebral blood flow was assessed by means of the oxygen-15-labeled water injection method, using high-resolution PET. Distinct patterns of activations were found. First, regarding the episodic memory condition, bilateral activations of the middle and superior frontal gyri and precuneus (more prominent on the right side) were observed. Second, the semantic memory condition disclosed extensive activations in the medial and orbital frontal cortex bilaterally, the left angular gyrus, and predominantly the left anterior part of the middle temporal gyri. The findings from this study are discussed in light of the available neuropsychological data obtained in brain-damaged subjects and functional neuroimaging studies.

Recognition memory, self-other source memory, and theory-of-mind in children with autism spectrum disorder.

PubMed

Lind, Sophie E; Bowler, Dermot M

2009-09-01

This study investigated semantic and episodic memory in autism spectrum disorder (ASD), using a task which assessed recognition and self-other source memory. Children with ASD showed undiminished recognition memory but significantly diminished source memory, relative to age- and verbal ability-matched comparison children. Both children with and without ASD showed an "enactment effect", demonstrating significantly better recognition and source memory for self-performed actions than other-person-performed actions. Within the comparison group, theory-of-mind (ToM) task performance was significantly correlated with source memory, specifically for other-person-performed actions (after statistically controlling for verbal ability). Within the ASD group, ToM task performance was not significantly correlated with source memory (after controlling for verbal ability). Possible explanations for these relations between source memory and ToM are considered.

Hippocampal activation during retrieval of spatial context from episodic and semantic memory.

PubMed

Hoscheidt, Siobhan M; Nadel, Lynn; Payne, Jessica; Ryan, Lee

2010-10-15

The hippocampus, a region implicated in the processing of spatial information and episodic memory, is central to the debate concerning the relationship between episodic and semantic memory. Studies of medial temporal lobe amnesic patients provide evidence that the hippocampus is critical for the retrieval of episodic but not semantic memory. On the other hand, recent neuroimaging studies of intact individuals report hippocampal activation during retrieval of both autobiographical memories and semantic information that includes historical facts, famous faces, and categorical information, suggesting that episodic and semantic memory may engage the hippocampus during memory retrieval in similar ways. Few studies have matched episodic and semantic tasks for the degree to which they include spatial content, even though spatial content may be what drives hippocampal activation during semantic retrieval. To examine this issue, we conducted a functional magnetic resonance imaging (fMRI) study in which retrieval of spatial and nonspatial information was compared during an episodic and semantic recognition task. Results show that the hippocampus (1) participates preferentially in the retrieval of episodic memories; (2) is also engaged by retrieval of semantic memories, particularly those that include spatial information. These data suggest that sharp dissociations between episodic and semantic memory may be overly simplistic and that the hippocampus plays a role in the retrieval of spatial content whether drawn from a memory of one's own life experiences or real-world semantic knowledge. Published by Elsevier B.V.

The effect of scene context on episodic object recognition: parahippocampal cortex mediates memory encoding and retrieval success.

PubMed

Hayes, Scott M; Nadel, Lynn; Ryan, Lee

2007-01-01

Previous research has investigated intentional retrieval of contextual information and contextual influences on object identification and word recognition, yet few studies have investigated context effects in episodic memory for objects. To address this issue, unique objects embedded in a visually rich scene or on a white background were presented to participants. At test, objects were presented either in the original scene or on a white background. A series of behavioral studies with young adults demonstrated a context shift decrement (CSD)-decreased recognition performance when context is changed between encoding and retrieval. The CSD was not attenuated by encoding or retrieval manipulations, suggesting that binding of object and context may be automatic. A final experiment explored the neural correlates of the CSD, using functional Magnetic Resonance Imaging. Parahippocampal cortex (PHC) activation (right greater than left) during incidental encoding was associated with subsequent memory of objects in the context shift condition. Greater activity in right PHC was also observed during successful recognition of objects previously presented in a scene. Finally, a subset of regions activated during scene encoding, such as bilateral PHC, was reactivated when the object was presented on a white background at retrieval. Although participants were not required to intentionally retrieve contextual information, the results suggest that PHC may reinstate visual context to mediate successful episodic memory retrieval. The CSD is attributed to automatic and obligatory binding of object and context. The results suggest that PHC is important not only for processing of scene information, but also plays a role in successful episodic memory encoding and retrieval. These findings are consistent with the view that spatial information is stored in the hippocampal complex, one of the central tenets of Multiple Trace Theory. (c) 2007 Wiley-Liss, Inc.

Audiovisual speech facilitates voice learning.

PubMed

Sheffert, Sonya M; Olson, Elizabeth

2004-02-01

In this research, we investigated the effects of voice and face information on the perceptual learning of talkers and on long-term memory for spoken words. In the first phase, listeners were trained over several days to identify voices from words presented auditorily or audiovisually. The training data showed that visual information about speakers enhanced voice learning, revealing cross-modal connections in talker processing akin to those observed in speech processing. In the second phase, the listeners completed an auditory or audiovisual word recognition memory test in which equal numbers of words were spoken by familiar and unfamiliar talkers. The data showed that words presented by familiar talkers were more likely to be retrieved from episodic memory, regardless of modality. Together, these findings provide new information about the representational code underlying familiar talker recognition and the role of stimulus familiarity in episodic word recognition.

Two processes support visual recognition memory in rhesus monkeys.

PubMed

Guderian, Sebastian; Brigham, Danielle; Mishkin, Mortimer

2011-11-29

A large body of evidence in humans suggests that recognition memory can be supported by both recollection and familiarity. Recollection-based recognition is characterized by the retrieval of contextual information about the episode in which an item was previously encountered, whereas familiarity-based recognition is characterized instead by knowledge only that the item had been encountered previously in the absence of any context. To date, it is unknown whether monkeys rely on similar mnemonic processes to perform recognition memory tasks. Here, we present evidence from the analysis of receiver operating characteristics, suggesting that visual recognition memory in rhesus monkeys also can be supported by two separate processes and that these processes have features considered to be characteristic of recollection and familiarity. Thus, the present study provides converging evidence across species for a dual process model of recognition memory and opens up the possibility of studying the neural mechanisms of recognition memory in nonhuman primates on tasks that are highly similar to the ones used in humans.

Two processes support visual recognition memory in rhesus monkeys

PubMed Central

Guderian, Sebastian; Brigham, Danielle; Mishkin, Mortimer

2011-01-01

A large body of evidence in humans suggests that recognition memory can be supported by both recollection and familiarity. Recollection-based recognition is characterized by the retrieval of contextual information about the episode in which an item was previously encountered, whereas familiarity-based recognition is characterized instead by knowledge only that the item had been encountered previously in the absence of any context. To date, it is unknown whether monkeys rely on similar mnemonic processes to perform recognition memory tasks. Here, we present evidence from the analysis of receiver operating characteristics, suggesting that visual recognition memory in rhesus monkeys also can be supported by two separate processes and that these processes have features considered to be characteristic of recollection and familiarity. Thus, the present study provides converging evidence across species for a dual process model of recognition memory and opens up the possibility of studying the neural mechanisms of recognition memory in nonhuman primates on tasks that are highly similar to the ones used in humans. PMID:22084079

Beyond the Memory Mechanism: Person-Selective and Nonselective Processes in Recognition of Personally Familiar Faces

ERIC Educational Resources Information Center

Sugiura, Motoaki; Mano, Yoko; Sasaki, Akihiro; Sadato, Norihiro

2011-01-01

Special processes recruited during the recognition of personally familiar people have been assumed to reflect the rich episodic and semantic information that selectively represents each person. However, the processes may also include person nonselective ones, which may require interpretation in terms beyond the memory mechanism. To examine this…

Perceptual Simulations and Linguistic Representations Have Differential Effects on Speeded Relatedness Judgments and Recognition Memory

PubMed Central

Tse, Chi-Shing; Kurby, Christopher A.; Du, Feng

2010-01-01

We examined the effect of spatial iconicity (a perceptual simulation of canonical locations of objects) and word-order frequency on language processing and episodic memory of orientation. Participants made speeded relatedness judgments to pairs of words presented in locations typical to their real world arrangements (e.g., ceiling on top and floor on bottom). They then engaged in a surprise orientation recognition task for the word pairs. We replicated Louwerse’s finding (2008) that word-order frequency has a stronger effect on semantic relatedness judgments than spatial iconicity. This is consistent with recent suggestions that linguistic representations have a stronger impact on immediate decisions about verbal materials than perceptual simulations. In contrast, spatial iconicity enhanced episodic memory of orientation to a greater extent than word-order frequency did. This new finding indicates that perceptual simulations have an important role in episodic memory. Results are discussed with respect to theories of perceptual representation and linguistic processing. PMID:19742388

Are There Multiple Kinds of Episodic Memory? An fMRI Investigation Comparing Autobiographical and Recognition Memory Tasks.

PubMed

Chen, Hung-Yu; Gilmore, Adrian W; Nelson, Steven M; McDermott, Kathleen B

2017-03-08

What brain regions underlie retrieval from episodic memory? The bulk of research addressing this question with fMRI has relied upon recognition memory for materials encoded within the laboratory. Another, less dominant tradition has used autobiographical methods, whereby people recall events from their lifetime, often after being cued with words or pictures. The current study addresses how the neural substrates of successful memory retrieval differed as a function of the targeted memory when the experimental parameters were held constant in the two conditions (except for instructions). Human participants studied a set of scenes and then took two types of memory test while undergoing fMRI scanning. In one condition (the picture memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it was recollected from the prior study episode. In a second condition (the life memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it reminded them of a specific event from their preexperimental lifetime. An examination of successful retrieval (yes responses) for recently studied scenes for the two test types revealed pronounced differences; that is, autobiographical retrieval instantiated with the life memory test preferentially activated the default mode network, whereas hits in the picture memory test preferentially engaged the parietal memory network as well as portions of the frontoparietal control network. When experimental cueing parameters are held constant, the neural underpinnings of successful memory retrieval differ when remembering life events and recently learned events. SIGNIFICANCE STATEMENT Episodic memory is often discussed as a solitary construct. However, experimental traditions examining episodic memory use very different approaches, and these are rarely compared to one another. When the neural correlates associated with each approach have been directly contrasted, results have varied considerably and at times contradicted each other. The present experiment was designed to match the two primary approaches to studying episodic memory in an unparalleled manner. Results suggest a clear separation of systems supporting memory as it is typically tested in the laboratory and memory as assessed under autobiographical retrieval conditions. These data provide neurobiological evidence that episodic memory is not a single construct, challenging the degree to which different experimental traditions are studying the same construct. Copyright © 2017 the authors 0270-6474/17/372764-12$15.00/0.

Effects of Sulpiride on True and False Memories of Thematically Related Pictures and Associated Words in Healthy Volunteers

PubMed Central

Guarnieri, Regina V.; Ribeiro, Rafaela L.; de Souza, Altay A. Lino; Galduróz, José Carlos F.; Covolan, Luciene; Bueno, Orlando F. A.

2016-01-01

Episodic memory, working memory, emotional memory, and attention are subject to dopaminergic modulation. However, the potential role of dopamine on the generation of false memories is unknown. This study defined the role of the dopamine D2 receptor on true and false recognition memories. Twenty-four young, healthy volunteers ingested a single dose of placebo or 400 mg oral sulpiride, a dopamine D2-receptor antagonist, just before starting the recognition memory task in a randomized, double-blind, and placebo-controlled trial. The sulpiride group presented more false recognitions during visual and verbal processing than the placebo group, although both groups had the same indices of true memory. These findings demonstrate that dopamine D2 receptors blockade in healthy volunteers can specifically increase the rate of false recognitions. The findings fit well the two-process view of causes of false memories, the activation/monitoring failures model. PMID:27047394

The ERP old-new effect: A useful indicator in studying the effects of sleep on memory retrieval processes.

PubMed

Mograss, Melodee; Godbout, Roger; Guillem, F

2006-11-01

To verify that the classic "Old/New" memory effect can be detected after a long delay, and to investigate the differential influence of declarative memory processes after normal sleep and daytime wake. The protocol is a variation of a more traditional study-recognition test used in event-related potential (ERP) studies in which sleep or wake is inserted between the learning and recognition session in order to verify the existence of the Old/New effect (ie, positive shift that occurs when stimuli are repeated). ERPs were recorded during the recognition-test session. The protocol was based on early work that compared the effect of sleep on memory without recording sleep. Data collection occurred in the outpatient sleep laboratory. Results from 13 subjects (6 men) aged between 21 and 39 years. The subjects performed the recognition memory test after sleep and daytime wake periods. More-accurate performance for the old (studied) stimuli occurred after the sleep session. Analysis of variance on correctly answered reaction times revealed a significant effect of condition (old/new) with no difference across session. A repeated-measure analysis revealed differences in "Old/New" effect, whereby the amplitude difference between the old and new items was larger after sleep than after wake. This effect of sleep was found in early frontal and later posterior ERP components, processes that represent strategic, contextual processing and facilitation of episodic memory. Memory representation was not different across sessions. These findings suggest that sleep and wake facilitate 2 components of memory unequally, ie, episodic recognition and memory representation functioning.

Memory retrieval and the parietal cortex: a review of evidence from a dual-process perspective.

PubMed

Vilberg, Kaia L; Rugg, Michael D

2008-01-01

Although regions of the parietal cortex have been consistently implicated in episodic memory retrieval, the functional roles of these regions remain poorly understood. The present review presents a meta-analysis of findings from event-related fMRI studies reporting the loci of retrieval effects associated with familiarity- and recollection-related recognition judgments. The results of this analysis support previous suggestions that retrieval-related activity in lateral parietal cortex dissociates between superior regions, where activity likely reflects the task relevance of different classes of recognition test items, and more inferior regions where retrieval-related activity appears closely linked to successful recollection. It is proposed that inferior lateral parietal cortex forms part of a neural network supporting the 'episodic buffer' [Baddeley, A. D. (2000). The episodic buffer: A new component of working memory? Trends in Cognitive Sciences, 4, 417-423].

Characterizing episodic memory retrieval: electrophysiological evidence for diminished familiarity following unitization.

PubMed

Pilgrim, Lea K; Murray, Jamie G; Donaldson, David I

2012-08-01

Episodic memory relies on both recollection and familiarity; why these processes are differentially engaged during retrieval remains unclear. Traditionally, recollection has been considered necessary for tasks requiring associative retrieval, whereas familiarity supports recognition of items. Recently, however, familiarity has been shown to contribute to associative recognition if stimuli are "unitized" at encoding (a single representation is created from multiple elements)-the "benefit" of unitization. Here, we ask if there is also a "cost" of unitization; are the elements of unitized representations less accessible via familiarity? We manipulated unitization during encoding and used ERPs to index familiarity and recollection at retrieval. The data revealed a selective reduction in the neural correlate of familiarity for individual words originally encoded in unitized compared with nonunitized word pairs. This finding reveals a measurable cost of unitization, suggesting that the nature of to-be-remembered stimuli is critical in determining whether familiarity contributes to episodic memory.

Neural dynamics associated with semantic and episodic memory for faces: evidence from multiple frequency bands.

PubMed

Zion-Golumbic, Elana; Kutas, Marta; Bentin, Shlomo

2010-02-01

Prior semantic knowledge facilitates episodic recognition memory for faces. To examine the neural manifestation of the interplay between semantic and episodic memory, we investigated neuroelectric dynamics during the creation (study) and the retrieval (test) of episodic memories for famous and nonfamous faces. Episodic memory effects were evident in several EEG frequency bands: theta (4-8 Hz), alpha (9-13 Hz), and gamma (40-100 Hz). Activity in these bands was differentially modulated by preexisting semantic knowledge and by episodic memory, implicating their different functional roles in memory. More specifically, theta activity and alpha suppression were larger for old compared to new faces at test regardless of fame, but were both larger for famous faces during study. This pattern of selective semantic effects suggests that the theta and alpha responses, which are primarily associated with episodic memory, reflect utilization of semantic information only when it is beneficial for task performance. In contrast, gamma activity decreased between the first (study) and second (test) presentation of a face, but overall was larger for famous than nonfamous faces. Hence, the gamma rhythm seems to be primarily related to activation of preexisting neural representations that may contribute to the formation of new episodic traces. Taken together, these data provide new insights into the complex interaction between semantic and episodic memory for faces and the neural dynamics associated with mnemonic processes.

Role of medial prefrontal cortex serotonin 2A receptors in the control of retrieval of recognition memory in rats.

PubMed

Bekinschtein, Pedro; Renner, Maria Constanza; Gonzalez, Maria Carolina; Weisstaub, Noelia

2013-10-02

Often, retrieval cues are not uniquely related to one specific memory, which could lead to memory interference. Controlling interference is particularly important during episodic memory retrieval or when remembering specific events in a spatiotemporal context. Despite a clear involvement of prefrontal cortex (PFC) in episodic memory in human studies, information regarding the mechanisms and neurotransmitter systems in PFC involved in memory is scarce. Although the serotoninergic system has been linked to PFC functionality and modulation, its role in memory processing is poorly understood. We hypothesized that the serotoninergic system in PFC, in particular the 5-HT2A receptor (5-HT2AR) could have a role in the control of memory retrieval. In this work we used different versions of the object recognition task in rats to study the role of the serotoninergic modulation in the medial PFC (mPFC) in memory retrieval. We found that blockade of 5-HT2AR in mPFC affects retrieval of an object in context memory in a spontaneous novelty preference task, while sparing single-item recognition memory. We also determined that 5-HT2ARs in mPFC are required for hippocampal-mPFC interaction during retrieval of this type of memory, suggesting that the mPFC controls the expression of memory traces stored in the hippocampus biasing retrieval to the most relevant one.

Donepezil Improves Episodic Memory in Young Individuals Vulnerable to the Effects of Sleep Deprivation

PubMed Central

Chuah, Lisa Y.M.; Chong, Delise L.; Chen, Annette K.; Rekshan, William R.; Tan, Jiat-Chow; Zheng, Hui; Chee, Michael W.L.

2009-01-01

Study Objectives: We investigated if donepezil, a long-acting orally administered cholinesterase inhibitor, would reduce episodic memory deficits associated with 24 h of sleep deprivation. Design: Double-blind, placebo-controlled, crossover study involving 7 laboratory visits over 2 months. Participants underwent 4 functional MRI scans; 2 sessions (donepezil or placebo) followed a normal night's sleep, and 2 sessions followed a night of sleep deprivation. Setting: The study took place in a research laboratory. Participants: 26 young, healthy volunteers with no history of any sleep, psychiatric, or neurologic disorders. Interventions: 5 mg of donepezil was taken once daily for approximately 17 days. Measurements and Results: Subjects were scanned while performing a semantic judgment task and tested for word recognition outside the scanner 45 minutes later. Sleep deprivation increased the frequency of non-responses at encoding and impaired delayed recognition. No benefit of donepezil was evident when participants were well rested. When sleep deprived, individuals who showed greater performance decline improved with donepezil, whereas more resistant individuals did not benefit. Accompanying these behavioral effects, there was corresponding modulation of task-related activation in functionally relevant brain regions. Brain regions identified in relation to donepezil-induced alteration in non-response rates could be distinguished from regions relating to improved recognition memory. This suggests that donepezil can improve delayed recognition in sleep-deprived persons by improving attention as well as enhancing memory encoding. Conclusions: Donepezil reduced decline in recognition performance in individuals vulnerable to the effects of sleep deprivation. Additionally, our findings demonstrate the utility of combined fMRI–behavior evaluation in psychopharmacological studies. Citation: Chuah LYM; Chong DL; Chen AK; Rekshan WR; Tan JC; Zheng H; Chee MWL. Donepezil improves episodic memory in young individuals vulnerable to the effects of sleep deprivation. SLEEP 2009;32(8):999-1010. PMID:19725251

Developmental differences in episodic memory across school ages: evidence from enacted events performed by self and others.

PubMed

Badinlou, Farzaneh; Kormi-Nouri, Reza; Mousavi Nasab, S M Hossein; Knopf, Monika

2017-01-01

The aim of this study was to examine action memory as a form of episodic memory among school-aged subjects. Most research on action memory has focused on memory changes in adult populations. This study explored the action memory of children over time. A total of 410 school-aged child participants, comprising 201 girls and 208 boys in four age groups (8, 10, 12, and 14), were included in this study. We studied two forms of action encoding, subject-performed tasks (SPTs) and experimenter-performed tasks (EPTs), which were compared with one verbal encoding task as a control condition. At retrieval, we used three memory tests (free recall, cued recall, and recognition). We observed significant differences in memory performance in children aged 8-14 years with respect to free recall and cued recall but not recognition. The largest memory enhancement was observed for the SPTs in the 8-14-year-old participants under all test conditions. Participants performed equally well on the free recall of SPTs and EPTs, whereas they displayed better performances on the cued recall and recognition of SPTs compared to EPTs. The strategic nature of SPTs and the distinction between item-specific information and relational information are discussed.

Some Memories Are Odder than Others: Judgments of Episodic Oddity Violate Known Decision Rules

ERIC Educational Resources Information Center

O'Connor, Akira R.; Guhl, Emily N.; Cox, Justin C.; Dobbins, Ian G.

2011-01-01

Current decision models of recognition memory are based almost entirely on one paradigm, single item old/new judgments accompanied by confidence ratings. This task results in receiver operating characteristics (ROCs) that are well fit by both signal-detection and dual-process models. Here we examine an entirely new recognition task, the judgment…

Some-or-None Recollection: Evidence from Item and Source Memory

ERIC Educational Resources Information Center

Onyper, Serge V.; Zhang, Yaofei X.; Howard, Marc W.

2010-01-01

Dual-process theory hypothesizes that recognition memory depends on 2 distinguishable memory signals. Recollection reflects conscious recovery of detailed information about the learning episode. Familiarity reflects a memory signal that is not accompanied by a vivid conscious experience but nonetheless enables participants to distinguish recently…

Electrolytic lesions of dorsal CA3 impair episodic-like memory in rats.

PubMed

Li, Jay-Shake; Chao, Yuen-Shin

2008-02-01

Episodic memory is the ability to recollect one's past experiences occurring in an unique spatial and temporal context. In non-human animals, it is expressed in the ability to combine "what", "where" and "when" factors to form an integrated memory system. During the search for its neural substrates, the hippocampus has attracted a lot of attentions. Yet, it is not yet possible to induce a pure episodic-like memory deficit in animal studies without being confounded by impairments in the spatial cognition. Here, we present a lesion study evidencing direct links between the hippocampus CA3 region and the episodic-like memory in rats. In a spontaneous object exploration task, lesioned rats showed no interaction between the temporal and spatial elements in their memory associated with the objects. In separate tests carried out subsequently, the same animals still expressed abilities to process spatial, temporal, and object recognition memory. In conclusions, our results support the idea that the hippocampus CA3 has a particular status in the neural mechanism of the episodic-like memory system. It is responsible for combining information from different modules of cognitive processes.

Temporal association tracts and the breakdown of episodic memory in mild cognitive impairment

PubMed Central

Metzler-Baddeley, Claudia; Hunt, Sarah; Jones, Derek K.; Leemans, Alexander; Aggleton, John P.

2012-01-01

Objective: To examine the pattern of association between microstructure of temporal lobe connections and the breakdown of episodic memory that is a core feature of mild cognitive impairment (MCI). Methods: Twenty-five individuals with MCI and 20 matched controls underwent diffusion MRI and cognitive assessment. Three temporal pathways were reconstructed by tractography: fornix, parahippocampal cingulum (PHC), and uncinate fasciculus. Tissue volume fraction—a tract-specific measure of atrophy—and microstructural measures were derived for each tract. To test specificity of associations, a comparison tract (corticospinal tract) and control cognitive domains were also examined. Results: In MCI, tissue volume fraction was reduced in the fornix. Axial and radial diffusivity were increased in uncinate and PHC implying more subtle microstructural change. In controls, tissue volume fraction in the fornix was the predominant correlate of free recall. In contrast, in MCI, the strongest relationship was with left PHC. Microstructure of uncinate and PHC also correlated with recognition memory, and recognition confidence, in MCI. Conclusions: Episodic memory in MCI is related to the structure of multiple temporal association pathways. These associations are not confined to the fornix, as they are in healthy young and older adults. In MCI, because of a compromised fornix, alternative pathways may contribute disproportionally to episodic memory performance. PMID:23175726

Lateral Entorhinal Cortex is Critical for Novel Object-Context Recognition

PubMed Central

Wilson, David IG; Langston, Rosamund F; Schlesiger, Magdalene I; Wagner, Monica; Watanabe, Sakurako; Ainge, James A

2013-01-01

Episodic memory incorporates information about specific events or occasions including spatial locations and the contextual features of the environment in which the event took place. It has been modeled in rats using spontaneous exploration of novel configurations of objects, their locations, and the contexts in which they are presented. While we have a detailed understanding of how spatial location is processed in the brain relatively little is known about where the nonspatial contextual components of episodic memory are processed. Initial experiments measured c-fos expression during an object-context recognition (OCR) task to examine which networks within the brain process contextual features of an event. Increased c-fos expression was found in the lateral entorhinal cortex (LEC; a major hippocampal afferent) during OCR relative to control conditions. In a subsequent experiment it was demonstrated that rats with lesions of LEC were unable to recognize object-context associations yet showed normal object recognition and normal context recognition. These data suggest that contextual features of the environment are integrated with object identity in LEC and demonstrate that recognition of such object-context associations requires the LEC. This is consistent with the suggestion that contextual features of an event are processed in LEC and that this information is combined with spatial information from medial entorhinal cortex to form episodic memory in the hippocampus. © 2013 Wiley Periodicals, Inc. PMID:23389958

The influence of encoding strategy on episodic memory and cortical activity in schizophrenia.

PubMed

Bonner-Jackson, Aaron; Haut, Kristen; Csernansky, John G; Barch, Deanna M

2005-07-01

Recent work suggests that episodic memory deficits in schizophrenia may be related to disturbances of encoding or retrieval. Schizophrenia patients appear to benefit from instruction in episodic memory strategies. We tested the hypothesis that providing effective encoding strategies to schizophrenia patients enhances encoding-related brain activity and recognition performance. Seventeen schizophrenia patients and 26 healthy comparison subjects underwent functional magnetic resonance imaging scans while performing incidental encoding tasks of words and faces. Subjects were required to make either deep (abstract/concrete) or shallow (alphabetization) judgments for words and deep (gender) judgments for faces, followed by subsequent recognition tests. Schizophrenia and comparison subjects recognized significantly more words encoded deeply than shallowly, activated regions in inferior frontal cortex (Brodmann area 45/47) typically associated with deep and successful encoding of words, and showed greater left frontal activation for the processing of words compared with faces. However, during deep encoding and material-specific processing (words vs. faces), participants with schizophrenia activated regions not activated by control subjects, including several in prefrontal cortex. Our findings suggest that a deficit in use of effective strategies influences episodic memory performance in schizophrenia and that abnormalities in functional brain activation persist even when such strategies are applied.

The effects of age, glucose ingestion and gluco-regulatory control on episodic memory.

PubMed

Riby, Leigh Martin; Meikle, Andrew; Glover, Cheryl

2004-09-01

Previous research has been inconclusive regarding the impact of glucose ingestion and gluco-regulatory control on cognitive performance in healthy older adults. The aim of this research was to determine whether glucose specifically enhanced episodic memory in an older population. In addition, the link between individual differences in glucose regulation and the magnitude of the enhancement effect was examined. A within subjects, counterbalanced, crossover design was used with 20 participants (60-80 year olds), each serving as his/her control. Episodic memory was tested by presenting unrelated paired associates followed by immediate and delayed cued recall, and delayed recognition, under single and dual task conditions. In addition, a battery of cognitive tests was administered, including tests of semantic memory, working memory and speed of processing. Glucose ingestion was found to largely facilitate performance of episodic memory. Furthermore, subsidiary analyses found that gluco-regulatory efficiency predicted episodic memory performance in both control and glucose conditions. A boost in performance after glucose ingestion was particularly seen in the episodic memory domain. Notably, strong evidence was provided for the utility of gluco-regulatory control measures as indicators of cognitive decline in the elderly.

Priming Effects in Word-Fragment Completion Are Independent of Recognition Memory.

ERIC Educational Resources Information Center

Tulving, Endel; And Others

1982-01-01

Since the priming effects described in this article were independent of episodic memory, and since there were problems with their interpretation in terms of modifications of semantic memory, it is felt that they reflect the operation of some other, as yet little understood, memory system. (Author/PN)

Mixed-handedness advantages in episodic memory obtained under conditions of intentional learning extend to incidental learning.

PubMed

Christman, Stephen D; Butler, Michael

2011-10-01

The existence of handedness differences in the retrieval of episodic memories is well-documented, but virtually all have been obtained under conditions of intentional learning. Two experiments are reported that extend the presence of such handedness differences to memory retrieval under conditions of incidental learning. Experiment 1 used Craik and Tulving's (1975) classic levels-of-processing paradigm and obtained handedness differences under incidental and intentional conditions of deep processing, but not under conditions of shallow incidental processing. Experiment 2 looked at incidental memory for distracter items from a recognition memory task and again found a mixed-handed advantage. Results are discussed in terms of the relation between interhemispheric interaction, levels of processing, and episodic memory retrieval. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of emotion and reward motivation on neural correlates of episodic memory encoding: a PET study.

PubMed

Shigemune, Yayoi; Abe, Nobuhito; Suzuki, Maki; Ueno, Aya; Mori, Etsuro; Tashiro, Manabu; Itoh, Masatoshi; Fujii, Toshikatsu

2010-05-01

It is known that emotion and reward motivation promote long-term memory formation. It remains unclear, however, how and where emotion and reward are integrated during episodic memory encoding. In the present study, subjects were engaged in intentional encoding of photographs under four different conditions that were made by combining two factors (emotional valence, negative or neutral; and monetary reward value, high or low for subsequent successful recognition) during H2 15O positron emission tomography (PET) scanning. As for recognition performance, we found significant main effects of emotional valence (negative>neutral) and reward value (high value>low value), without an interaction between the two factors. Imaging data showed that the left amygdala was activated during the encoding conditions of negative pictures relative to neutral pictures, and the left orbitofrontal cortex was activated during the encoding conditions of high reward pictures relative to low reward pictures. In addition, conjunction analysis of these two main effects detected right hippocampal activation. Although we could not find correlations between recognition performance and activity of these three regions, we speculate that the right hippocampus may integrate the effects of emotion (processed in the amygdala) and monetary reward (processed in the orbitofrontal cortex) on episodic memory encoding. 2010 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Dopamine and Consolidation of Episodic Memory: Timing Is Everything

PubMed Central

Grogan, John; Bogacz, Rafal; Tsivos, Demitra; Whone, Alan; Coulthard, Elizabeth

2016-01-01

Memory consolidation underpins adaptive behavior and dopaminergic networks may be critical for prolonged, selective information storage. To understand the time course of the dopaminergic contribution to memory consolidation in humans, here we investigate the effect of dopaminergic medication on recall and recognition in the short and longer term in Parkinson disease (PD). Fifteen people with PD were each tested on or off dopaminergic medication during learning/early consolidation (Day 1) and/or late consolidation (Day 2). Fifteen age-matched healthy participants were tested only once. On Day 1 participants learned new information, and early episodic memory was tested after 30 min. Then on Day 2, recall and recognition were retested after a 24-hr delay. Participants on medication on Day 1 recalled less information at 30 min and 24 hr. In contrast, patients on medication on Day 2 (8–24 hr after learning) recalled more information at 24 hr than those off medication. Although recognition sensitivity was unaffected by medication, response bias was dependent on dopaminergic state: Medication during learning induced a more liberal bias 24 hr later, whereas patients off medication during learning were more conservative responders 24 hr later. We use computational modeling to propose possible mechanisms for this change in response bias. In summary, dopaminergic medication in PD patients during learning impairs early consolidation of episodic memory and makes delayed responses more liberal, but enhances late memory consolidation presumably through a dopamine-dependent consolidation pathway that may be active during sleep. PMID:26102227

Information and processes underlying semantic and episodic memory across tasks, items, and individuals.

PubMed

Cox, Gregory E; Hemmer, Pernille; Aue, William R; Criss, Amy H

2018-04-01

The development of memory theory has been constrained by a focus on isolated tasks rather than the processes and information that are common to situations in which memory is engaged. We present results from a study in which 453 participants took part in five different memory tasks: single-item recognition, associative recognition, cued recall, free recall, and lexical decision. Using hierarchical Bayesian techniques, we jointly analyzed the correlations between tasks within individuals-reflecting the degree to which tasks rely on shared cognitive processes-and within items-reflecting the degree to which tasks rely on the same information conveyed by the item. Among other things, we find that (a) the processes involved in lexical access and episodic memory are largely separate and rely on different kinds of information, (b) access to lexical memory is driven primarily by perceptual aspects of a word, (c) all episodic memory tasks rely to an extent on a set of shared processes which make use of semantic features to encode both single words and associations between words, and (d) recall involves additional processes likely related to contextual cuing and response production. These results provide a large-scale picture of memory across different tasks which can serve to drive the development of comprehensive theories of memory. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Mild traumatic brain injury: graph-model characterization of brain networks for episodic memory.

PubMed

Tsirka, Vasso; Simos, Panagiotis G; Vakis, Antonios; Kanatsouli, Kassiani; Vourkas, Michael; Erimaki, Sofia; Pachou, Ellie; Stam, Cornelis Jan; Micheloyannis, Sifis

2011-02-01

Episodic memory is among the cognitive functions that can be affected in the acute phase following mild traumatic brain injury (MTBI). The present study used EEG recordings to evaluate global synchronization and network organization of rhythmic activity during the encoding and recognition phases of an episodic memory task varying in stimulus type (kaleidoscope images, pictures, words, and pseudowords). Synchronization of oscillatory activity was assessed using a linear and nonlinear connectivity estimator and network analyses were performed using algorithms derived from graph theory. Twenty five MTBI patients (tested within days post-injury) and healthy volunteers were closely matched on demographic variables, verbal ability, psychological status variables, as well as on overall task performance. Patients demonstrated sub-optimal network organization, as reflected by changes in graph parameters in the theta and alpha bands during both encoding and recognition. There were no group differences in spectral energy during task performance or on network parameters during a control condition (rest). Evidence of less optimally organized functional networks during memory tasks was more prominent for pictorial than for verbal stimuli. Copyright © 2010 Elsevier B.V. All rights reserved.

Neural Correlates of Conceptual Implicit Memory and Their Contamination of Putative Neural Correlates of Explicit Memory

ERIC Educational Resources Information Center

Voss, Joel L.; Paller, Ken A.

2007-01-01

During episodic recognition tests, meaningful stimuli such as words can engender both conscious retrieval (explicit memory) and facilitated access to meaning that is distinct from the awareness of remembering (conceptual implicit memory). Neuroimaging investigations of one type of memory are frequently subject to the confounding influence of the…

Common and unique gray matter correlates of episodic memory dysfunction in frontotemporal dementia and Alzheimer's disease.

PubMed

Irish, Muireann; Piguet, Olivier; Hodges, John R; Hornberger, Michael

2014-04-01

Conflicting evidence exists regarding the integrity of episodic memory in the behavioral variant of frontotemporal dementia (bvFTD). Recent converging evidence suggests that episodic memory in progressive cases of bvFTD is compromised to the same extent as in Alzheimer's disease (AD). The underlying neural substrates of these episodic memory deficits, however, likely differ contingent on dementia type. In this study we sought to elucidate the neural substrates of episodic memory performance, across recall and recognition tasks, in both patient groups using voxel-based morphometry (VBM) analyses. We predicted that episodic memory dysfunction would be apparent in both patient groups but would relate to divergent patterns of neural atrophy specific to each dementia type. We assessed episodic memory, across verbal and visual domains, in 19 bvFTD, 18 AD patients, and 19 age- and education-matched controls. Behaviorally, patient groups were indistinguishable for immediate and delayed recall, across verbal and visual domains. Whole-brain VBM analyses revealed regions commonly implicated in episodic retrieval across groups, namely the right temporal pole, right frontal lobe, left paracingulate gyrus, and right anterior hippocampus. Divergent neural networks specific to each group were also identified. Whereas a widespread network including posterior regions such as the posterior cingulate cortex, parietal and occipital cortices was exclusively implicated in AD, the frontal and anterior temporal lobes underpinned the episodic memory deficits in bvFTD. Our results point to distinct neural changes underlying episodic memory decline specific to each dementia syndrome. Copyright © 2013 Wiley Periodicals, Inc.

Sleep Enhances Recognition Memory for Conspecifics as Bound into Spatial Context

PubMed Central

Sawangjit, Anuck; Kelemen, Eduard; Born, Jan; Inostroza, Marion

2017-01-01

Social memory refers to the fundamental ability of social species to recognize their conspecifics in quite different contexts. Sleep has been shown to benefit consolidation, especially of hippocampus-dependent episodic memory whereas effects of sleep on social memory are less well studied. Here, we examined the effect of sleep on memory for conspecifics in rats. To discriminate interactions between the consolidation of social memory and of spatial context during sleep, adult Long Evans rats performed on a social discrimination task in a radial arm maze. The Learning phase comprised three 10-min sampling sessions in which the rats explored a juvenile rat presented at a different arm of the maze in each session. Then the rats were allowed to sleep (n = 18) or stayed awake (n = 18) for 120 min. During the following 10-min Test phase, the familiar juvenile rat (of the Learning phase) was presented along with a novel juvenile rat, each rat at an opposite arm of the maze. Significant social recognition memory, as indicated by preferential exploration of the novel over the familiar conspecific, occurred only after post-learning sleep, but not after wakefulness. Sleep, compared with wakefulness, significantly enhanced social recognition during the first minute of the Test phase. However, memory expression depended on the spatial configuration: Significant social recognition memory emerged only after sleep when the rat encountered the novel conspecific at a place different from that of the familiar juvenile in the last sampling session before sleep. Though unspecific retrieval-related effects cannot entirely be excluded, our findings suggest that sleep, rather than independently enhancing social and spatial aspects of memory, consolidates social memory by acting on an episodic representation that binds the memory of the conspecific together with the spatial context in which it was recently encountered. PMID:28270755

Music-related reward responses predict episodic memory performance.

PubMed

Ferreri, Laura; Rodriguez-Fornells, Antoni

2017-12-01

Music represents a special type of reward involving the recruitment of the mesolimbic dopaminergic system. According to recent theories on episodic memory formation, as dopamine strengthens the synaptic potentiation produced by learning, stimuli triggering dopamine release could result in long-term memory improvements. Here, we behaviourally test whether music-related reward responses could modulate episodic memory performance. Thirty participants rated (in terms of arousal, familiarity, emotional valence, and reward) and encoded unfamiliar classical music excerpts. Twenty-four hours later, their episodic memory was tested (old/new recognition and remember/know paradigm). Results revealed an influence of music-related reward responses on memory: excerpts rated as more rewarding were significantly better recognized and remembered. Furthermore, inter-individual differences in the ability to experience musical reward, measured through the Barcelona Music Reward Questionnaire, positively predicted memory performance. Taken together, these findings shed new light on the relationship between music, reward and memory, showing for the first time that music-driven reward responses are directly implicated in higher cognitive functions and can account for individual differences in memory performance.

Turning up the noise or turning down the volume? On the nature of the impairment of episodic recognition memory by midazolam.

PubMed

Malmberg, Kenneth J; Zeelenberg, Rene; Shiffrin, Richard M

2004-03-01

E. Hirshman, J. Fisher, T. Henthom, J. Amdt, and A. Passanname (2002) found that Midazolam disrupts the mirror-patterned word-frequency effect for recognition memory by reversing the typical hit-rate advantage for low-frequency words. They noted that this result is consistent with dual-process accounts (e.g., R. C. Atkinson & J. F. Juola, 1974; G. Mandler, 1980; A. P. Yonelinas, 1994) of the word frequency effect for recognition memory (S. Joordens & W. E. Hockley. 2000; L. M. Reder et al. 2000). The present authors show that this finding is also consistent with a variety of single-process, retrieving effectively- from-memory (REM) models (R. M. Shiffrin & M. Steyvers, 1997), the simplest of which assumes that Midazolam decreases the accuracy with which memory traces are stored. These findings therefore do not discriminate between single- and dual-process models of recognition memory.

Electrophysiological correlates of encoding and retrieving emotional events.

PubMed

Koenig, Stefanie; Mecklinger, Axel

2008-04-01

This study examined the impact of emotional content on encoding and retrieval processes. Event-related potentials were recorded in a source recognition memory task. During encoding, a posterior positivity for positive and negative pictures (250-450 ms) that presumably reflects attentional capturing of emotionally valenced stimuli was found. Additionally, positive events, which were also rated as less arousing than negative events, gave rise to anterior and posterior slow wave activity as compared with neutral and negative events and also showed enhanced recognition memory. It is assumed that positive low-arousing events enter controlled and elaborated encoding processes that are beneficial for recognition memory performance. The high arousal of negative events may interfere with controlled encoding mechanisms and attenuate item recognition and the quality of remembering. Moreover, topographically distinct late posterior negativities were obtained for the retrieval of the context features location and time that support the view that this component reflects processes in service of reconstructing the study episode by binding together contextual details with an item and that varies with the kind of episodic detail to be retrieved. (Copyright) 2008 APA.

Encoding-related brain activity during deep processing of verbal materials: a PET study.

PubMed

Fujii, Toshikatsu; Okuda, Jiro; Tsukiura, Takashi; Ohtake, Hiroya; Suzuki, Maki; Kawashima, Ryuta; Itoh, Masatoshi; Fukuda, Hiroshi; Yamadori, Atsushi

2002-12-01

The recent advent of neuroimaging techniques provides an opportunity to examine brain regions related to a specific memory process such as episodic memory encoding. There is, however, a possibility that areas active during an assumed episodic memory encoding task, compared with a control task, involve not only areas directly relevant to episodic memory encoding processes but also areas associated with other cognitive processes for on-line information. We used positron emission tomography (PET) to differentiate these two kinds of regions. Normal volunteers were engaged in deep (semantic) or shallow (phonological) processing of new or repeated words during PET. Results showed that deep processing, compared with shallow processing, resulted in significantly better recognition performance and that this effect was associated with activation of various brain areas. Further analyses revealed that there were regions directly relevant to episodic memory encoding in the anterior part of the parahippocampal gyrus, inferior frontal gyrus, supramarginal gyrus, anterior cingulate gyrus, and medial frontal lobe in the left hemisphere. Our results demonstrated that several regions, including the medial temporal lobe, play a role in episodic memory encoding.

"When Did I Learn and When Shall I Act?": The Developmental Relationship between Episodic Future Thinking and Memory

ERIC Educational Resources Information Center

Naito, Mika; Suzuki, Toshiko

2011-01-01

This study investigated the development of the ability to reflect on one's personal past and future. A total of 64 4- to 6-year-olds received tasks of delayed self-recognition, source memory, delay of gratification, and a newly developed task of future-oriented action timing. Although children's performance on delayed self-recognition, source…

Benefits and Costs of Context Reinstatement in Episodic Memory: An ERP Study.

PubMed

Bramão, Inês; Johansson, Mikael

2017-01-01

This study investigated context-dependent episodic memory retrieval. An influential idea in the memory literature is that performance benefits when the retrieval context overlaps with the original encoding context. However, such memory facilitation may not be driven by the encoding-retrieval overlap per se but by the presence of diagnostic features in the reinstated context that discriminate the target episode from competing episodes. To test this prediction, the encoding-retrieval overlap and the diagnostic value of the context were manipulated in a novel associative recognition memory task. Participants were asked to memorize word pairs presented together with diagnostic (unique) and nondiagnostic (shared) background scenes. At test, participants recognized the word pairs in the presence and absence of the previously encoded contexts. Behavioral data show facilitated memory performance in the presence of the original context but, importantly, only when the context was diagnostic of the target episode. The electrophysiological data reveal an early anterior ERP encoding-retrieval overlap effect that tracks the cost associated with having nondiagnostic contexts present at retrieval, that is, shared by multiple previous episodes, and a later posterior encoding-retrieval overlap effect that reflects facilitated access to the target episode during retrieval in diagnostic contexts. Taken together, our results underscore the importance of the diagnostic value of the context and suggest that context-dependent episodic memory effects are multiple determined.

The Influence of Encoding Strategy on Episodic Memory and Cortical Activity in Schizophrenia

PubMed Central

Haut, Kristen; Csernansky, John G.; Barch, Deanna M.

2005-01-01

Background: Recent work suggests that episodic memory deficits in schizophrenia may be related to disturbances of encoding or retrieval. Schizophrenia patients appear to benefit from instruction in episodic memory strategies. We tested the hypothesis that providing effective encoding strategies to schizophrenia patients enhances encoding-related brain activity and recognition performance. Methods: Seventeen schizophrenia patients and 26 healthy comparison subjects underwent functional magnetic resonance imaging scans while performing incidental encoding tasks of words and faces. Subjects were required to make either deep (abstract/concrete) or shallow (alphabetization) judgments for words and deep (gender) judgments for faces, followed by subsequent recognition tests. Results: Schizophrenia and comparison subjects recognized significantly more words encoded deeply than shallowly, activated regions in inferior frontal cortex (Brodmann area 45/47) typically associated with deep and successful encoding of words, and showed greater left frontal activation for the processing of words compared with faces. However, during deep encoding and material-specific processing (words vs. faces), participants with schizophrenia activated regions not activated by control subjects, including several in prefrontal cortex. Conclusions: Our findings suggest that a deficit in use of effective strategies influences episodic memory performance in schizophrenia and that abnormalities in functional brain activation persist even when such strategies are applied. PMID:15992522

The Hippocampus Remains Activated over the Long Term for the Retrieval of Truly Episodic Memories

PubMed Central

Harand, Caroline; Bertran, Françoise; La Joie, Renaud; Landeau, Brigitte; Mézenge, Florence; Desgranges, Béatrice; Peigneux, Philippe; Eustache, Francis; Rauchs, Géraldine

2012-01-01

The role of the hippocampus in declarative memory consolidation is a matter of intense debate. We investigated the neural substrates of memory retrieval for recent and remote information using functional magnetic resonance imaging (fMRI). 18 young, healthy participants learned a series of pictures. Then, during two fMRI recognition sessions, 3 days and 3 months later, they had to determine whether they recognized or not each picture using the “Remember/Know” procedure. Presentation of the same learned images at both delays allowed us to track the evolution of memories and distinguish consistently episodic memories from those that were initially episodic and then became familiar or semantic over time and were retrieved without any contextual detail. Hippocampal activation decreased over time for initially episodic, later semantic memories, but remained stable for consistently episodic ones, at least in its posterior part. For both types of memories, neocortical activations were observed at both delays, notably in the ventromedial prefrontal and anterior cingulate cortices. These activations may reflect a gradual reorganization of memory traces within neural networks. Our data indicate maintenance and strengthening of hippocampal and cortico-cortical connections in the consolidation and retrieval of episodic memories over time, in line with the Multiple Trace theory (Nadel and Moscovitch, 1997). At variance, memories becoming semantic over time consolidate through strengthening of cortico-cortical connections and progressive disengagement of the hippocampus. PMID:22937055

Antiretroviral Non-Adherence is Associated With a Retrieval Profile of Deficits in Verbal Episodic Memory.

PubMed

Obermeit, Lisa C; Morgan, Erin E; Casaletto, Kaitlin B; Grant, Igor; Woods, Steven Paul

2015-01-01

HIV-associated deficits in verbal episodic memory are commonly associated with antiretroviral non-adherence; however, the specific aspects of memory functioning (e.g., encoding, consolidation, or retrieval) that underlie this established relationship are not well understood. This study evaluated verbal memory profiles of 202 HIV+ participants who underwent a 30-day electronic monitoring of antiretroviral adherence. At the group level, non-adherence was significantly associated with lower scores on immediate and delayed passage recall and word list learning. Retention and recognition of passages and word lists were not related to adherence. Participants were then classified as having either a normal verbal memory profile, a "subcortical" retrieval profile (i.e., impaired free recall with relatively spared recognition), or a "cortical" encoding profile (e.g., cued recall intrusions) based on the Massman et al. ( 1990 ) algorithm for the California Verbal Learning Test. HIV+ participants with a classic retrieval deficit had significantly greater odds of being non-adherent than participants with a normal or encoding profile. These findings suggest that adherence to prescribed antiretroviral regimens may be particularly vulnerable to disruption in HIV+ individuals due to deficits in the complex process of efficiently accessing verbal episodic information with minimal cues. A stronger relationship between non-adherence and passage (vs. word list) recall was also found and may reflect the importance of contextual features in remembering to take medications. Targeted interventions for enhancing and supporting episodic memory retrieval processes may improve antiretroviral adherence and overall health outcomes among persons living with HIV.

Episodic memory functions in first episode psychosis and clinical high risk individuals.

PubMed

Greenland-White, Sarah E; Ragland, J Daniel; Niendam, Tara A; Ferrer, Emilio; Carter, Cameron S

2017-10-01

Individuals with schizophrenia have disproportionate memory impairments when encoding relational versus item-specific information, and when using recollection versus familiarity during retrieval. It is unclear whether this pattern is unique to people with chronic schizophrenia, or if it occurs in individuals after a first episode of psychosis (FE), or when at clinical high-risk for psychosis (CHR). We administered the Relational and Item-Specific Memory task (RiSE) to 22 CHR, 101 FE, and 58 typically developing (TD) participants. We examined group differences in item and relational encoding, and familiarity-based and recollection-based retrieval using parametric analysis and structural equation modeling (SEM). Longitudinal data allowed us to examine relations between baseline RiSE performance and change in clinical symptoms at 1-year follow-up in the FE group. Groups did not differ on familiarity. FE and CHR groups were equally impaired on overall recognition accuracy. Although recollection was impaired in both FE and CHR groups following relational encoding, only the FE group had impaired recollection following item encoding. SEM showed atypical relationships between familiarity and recollection, as well as familiarity and item recognition for both the FE and CHR groups. For FE individuals, better baseline recognition accuracy predicted less severe negative symptoms at 1-year follow-up. Impaired relational and recollective memory may reflect neurodevelopmental abnormalities predating conversion to psychosis. These memory deficits appear related to negative symptom changes. In contrast, item specific recollection deficits appear to occur after the development of full psychosis. Familiarity appears to be a relatively preserved memory function across the psychosis spectrum. Copyright © 2017 Elsevier B.V. All rights reserved.

Stereotype Threat Effects on Older Adults' Episodic and Working Memory: A Meta-Analysis.

PubMed

Armstrong, Bonnie; Gallant, Sara N; Li, Lingqian; Patel, Khushi; Wong, Brenda I

2017-08-01

Prior research has shown that exposure to negative age-based stereotype threat (ST) can undermine older adults' memory performance. The objective of the current meta-analysis was to examine the reliability and magnitude of ST effects on older adults' episodic and working memory performance-two forms of memory that typically show the greatest age-related declines. In addition, we examined potential moderators of age-based ST including type of ST manipulation, type and timing of memory task, participant age and education level. A total of 23 samples for episodic memory and 15 samples for working memory were derived from 19 published and 4 unpublished articles and analyzed in two separate meta-analyses. Analyses revealed a reliable effect of ST on both older adults' episodic (d = 0.373) and working memory performance (d = 0.253). Interestingly, the age-based ST effect was only significant when blatant ST manipulations were used with episodic memory tasks or when subtle ST manipulations were used with working memory tasks. Moreover, within episodic memory, the ST effect only reached significance for recall but not cued-recall or recognition performance, and for immediate but not delayed tests of memory. Neither age nor level of education moderated the association between ST and older adults' memory performance. These results highlight the vulnerability of both older adults' episodic and working memory performance to age-based ST. When measuring older adults' memory performance in a research context, we must therefore be wary of exposing participants to common stereotypes about aging and memory. © The Author 2017. 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.

The effect of hippocampal function, volume and connectivity on posterior cingulate cortex functioning during episodic memory fMRI in mild cognitive impairment.

PubMed

Papma, Janne M; Smits, Marion; de Groot, Marius; Mattace Raso, Francesco U; van der Lugt, Aad; Vrooman, Henri A; Niessen, Wiro J; Koudstaal, Peter J; van Swieten, John C; van der Veen, Frederik M; Prins, Niels D

2017-09-01

Diminished function of the posterior cingulate cortex (PCC) is a typical finding in early Alzheimer's disease (AD). It is hypothesized that in early stage AD, PCC functioning relates to or reflects hippocampal dysfunction or atrophy. The aim of this study was to examine the relationship between hippocampus function, volume and structural connectivity, and PCC activation during an episodic memory task-related fMRI study in mild cognitive impairment (MCI). MCI patients (n = 27) underwent episodic memory task-related fMRI, 3D-T1w MRI, 2D T2-FLAIR MRI and diffusion tensor imaging. Stepwise linear regression analysis was performed to examine the relationship between PCC activation and hippocampal activation, hippocampal volume and diffusion measures within the cingulum along the hippocampus. We found a significant relationship between PCC and hippocampus activation during successful episodic memory encoding and correct recognition in MCI patients. We found no relationship between the PCC and structural hippocampal predictors. Our results indicate a relationship between PCC and hippocampus activation during episodic memory engagement in MCI. This may suggest that during episodic memory, functional network deterioration is the most important predictor of PCC functioning in MCI. • PCC functioning during episodic memory relates to hippocampal functioning in MCI. • PCC functioning during episodic memory does not relate to hippocampal structure in MCI. • Functional network changes are an important predictor of PCC functioning in MCI.

Evidence for a Specific Integrative Mechanism for Episodic Memory Mediated by AMPA/kainate Receptors in a Circuit Involving Medial Prefrontal Cortex and Hippocampal CA3 Region.

PubMed

de Souza Silva, Maria A; Huston, Joseph P; Wang, An-Li; Petri, David; Chao, Owen Yuan-Hsin

2016-07-01

We asked whether episodic-like memory requires neural mechanisms independent of those that mediate its component memories for "what," "when," and "where," and if neuronal connectivity between the medial prefrontal cortex (mPFC) and the hippocampus (HPC) CA3 subregion is essential for episodic-like memory. Unilateral lesion of the mPFC was combined with unilateral lesion of the CA3 in the ipsi- or contralateral hemispheres in rats. Episodic-like memory was tested using a task, which assesses the integration of memories for "what, where, and when" concomitantly. Tests for novel object recognition (what), object place (where), and temporal order memory (when) were also applied. Bilateral disconnection of the mPFC-CA3 circuit by N-methyl-d-aspartate (NMDA) lesions disrupted episodic-like memory, but left the component memories for object, place, and temporal order, per se, intact. Furthermore, unilateral NMDA lesion of the CA3 plus injection of (6-cyano-7-nitroquinoxaline-2,3-dione) (CNQX) (AMPA/kainate receptor antagonist), but not AP-5 (NMDA receptor antagonist), into the contralateral mPFC also disrupted episodic-like memory, indicating the mPFC AMPA/kainate receptors as critical for this circuit. These results argue for a selective neural system that specifically subserves episodic memory, as it is not critically involved in the control of its component memories for object, place, and time. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Visual associations to retrieve episodic memory across healthy elderly, mild cognitive impairment, and patients with Alzheimer's disease.

PubMed

Meyer, Sascha R A; De Jonghe, Jos F M; Schmand, Ben; Ponds, Rudolf W H M

2018-05-16

Episodic memory tests need to determine the degree to which patients with moderate to severe memory deficits can still benefit from retrieval support. Especially in the case of Alzheimer's disease (AD), this may support health care to be more closely aligned with patients' memory capacities. We investigated whether the different measures of episodic memory of the Visual Association Test-Extended (VAT-E) can provide a more detailed and informative assessment on memory disturbances across a broad range of cognitive decline, from normal to severe impairment as seen in AD, by examining differences in floor effects. The VAT-E consists of 24 pairs of black-and-white line drawings. In a within-group design, we compared score distributions of VAT-E subtests in healthy elderly controls, mild cognitive impairment (MCI), and AD (n = 144), as well as in relation to global cognitive impairment. Paired associate recall showed a floor effect in 41% of MCI patients and 62% of AD patients. Free recall showed a floor effect in 73% of MCI patients and 84% of AD patients. Multiple-choice cued recognition did not show a floor effect in either of the patient groups. We conclude that the VAT-E covers a broad range of episodic memory decline in patients. As expected, paired associate recall was of intermediate difficulty, free recall was most difficult, and multiple-choice cued recognition was least difficult for patients. These varying levels of difficulty enable a more accurate determination of the level of retrieval support that can still benefit patients across a broad range of cognitive decline.

Differences in Binding and Monitoring Mechanisms Contribute to Lifespan Age Differences in False Memory

ERIC Educational Resources Information Center

Fandakova, Yana; Shing, Yee Lee; Lindenberger, Ulman

2013-01-01

Based on a 2-component framework of episodic memory development across the lifespan (Shing & Lindenberger, 2011), we examined the contribution of memory-related binding and monitoring processes to false memory susceptibility in childhood and old age. We administered a repeated continuous recognition task to children (N = 20, 10-12 years),…

The self-reference effect on episodic memory recollection in young and older adults and Alzheimer's disease.

PubMed

Lalanne, Jennifer; Rozenberg, Johanna; Grolleau, Pauline; Piolino, Pascale

2013-12-01

The Self-reference effect (SRE) on long-term episodic memory and autonoetic consciousness has been investigated in young adults, scarcely in older adults, but never in Alzheimer's patients. Is the functional influence of Selfreference still present when the individual's memory and identity are impaired? We investigated this issue in 60 young subjects, 41 elderly subjects, and 28 patients with Alzheimer's disease, by using 1) an incidental learning task of personality traits in three encoding conditions, inducing variable degrees of depth of processing and personal involvement, 2) a 2- minute retention interval free recall task, and 3) a 20-minute delayed recognition task, combined with a remember-know paradigm. Each recorded score was corrected for errors (intrusions in free recall, false alarms in recognition, and false source memory in remember responses). Compared with alternative encodings, the Self-reference significantly enhanced performance on the free recall task in the young group, and on the recognition task both in the young and older groups but not in the Alzheimer group. The most important finding in the Alzheimer group is that the Self-reference led the most often to a subjective sense of remembering (especially for the positive words) with the retrieval of the correct encoding source. This Self-reference recollection effect in patients was related to independent subjective measures of a positive and definite sense of Self (measured by the Tennessee Self Concept Scale), and to memory complaints in daily life. In conclusion, these results demonstrated the power and robustness of the Self-reference effect on recollection in long-term episodic memory in Alzheimer's disease, albeit the retrieval is considerably reduced. These results should open new perspectives for the development of rehabilitation programs for memory deficits.

Hippocampal dentation: Structural variation and its association with episodic memory in healthy adults.

PubMed

Fleming Beattie, Julia; Martin, Roy C; Kana, Rajesh K; Deshpande, Hrishikesh; Lee, Seongtaek; Curé, Joel; Ver Hoef, Lawrence

2017-07-01

While the hippocampus has long been identified as a structure integral to memory, the relationship between morphology and function has yet to be fully explained. We present an analysis of hippocampal dentation, a morphological feature previously unexplored in regard to its relationship with episodic memory. "Hippocampal dentation" in this case refers to surface convolutions, primarily present in the CA1/subiculum on the inferior aspect of the hippocampus. Hippocampal dentation was visualized using ultra-high resolution structural MRI and evaluated using a novel visual rating scale. The degree of hippocampal dentation was found to vary considerably across individuals, and was positively associated with verbal memory recall and visual memory recognition in a sample of 22 healthy adults. This study is the first to characterize the variation in hippocampal dentation in a healthy cohort and to demonstrate its association with aspects of episodic memory. Copyright © 2017 Elsevier Ltd. All rights reserved.

Turning up the Noise or Turning Down the Volume? On the Nature of the Impairment of Episodic Recognition Memory by Midazolam

ERIC Educational Resources Information Center

Malmberg, Kenneth J.; Zeelenberg, Rene; Shiffrin, Richard M.

2004-01-01

E. Hirshman, J. Fisher, T. Henthom, J. Amdt, and A. Passanname (2002) found that Midazolam disrupts the mirror-patterned word-frequency effect for recognition memory by reversing the typical hit-rate advantage for low-frequency words. They noted that this result is consistent with dual-process accounts (e.g., R. C. Atkinson & J. F. Juola, 1974; G.…

Color and context: an ERP study on intrinsic and extrinsic feature binding in episodic memory.

PubMed

Ecker, Ullrich K H; Zimmer, Hubert D; Groh-Bordin, Christian

2007-09-01

Episodic memory for intrinsic item and extrinsic context information is postulated to rely on two distinct types of representation: object and episodic tokens. These provide the basis for familiarity and recollection, respectively. Electrophysiological indices of these processes (ERP old-new effects) were used together with behavioral data to test these assumptions. We manipulated an intrinsic object feature (color; Experiment 1) and a contextual feature (background; Experiments 1 and 2). In an inclusion task (Experiment 1), the study-test manipulation of color affected object recognition performance and modulated ERP old-new effects associated with both familiarity and recollection. In contrast, a contextual manipulation had no effect, although both intrinsic and extrinsic information was available in a direct feature (source memory) test. When made task relevant (exclusion task; Experiment 2), however, context affected the ERP recollection effect, while still leaving the ERP familiarity effect uninfluenced. We conclude that intrinsic features bound in object tokens are involuntarily processed during object recognition, thus influencing familiarity, whereas context features bound in episodic tokens are voluntarily accessed, exclusively influencing recollection. Figures depicting all the electrodes analyzed are available in an online supplement at www.psychonomic.org/archive.

A Diffusion Model Analysis of Episodic Recognition in Individuals with a Family History for Alzheimer Disease: The Adult Children Study

PubMed Central

Aschenbrenner, Andrew J.; Balota, David A.; Gordon, Brian A.; Ratcliff, Roger; Morris, John C.

2015-01-01

Objective A family history of Alzheimer disease (AD) increases the risk of developing AD and can influence the accumulation of well-established AD biomarkers. There is some evidence that family history can influence episodic memory performance even in cognitively normal individuals. We attempted to replicate the effect of family history on episodic memory and used a specific computational model of binary decision making (the diffusion model) to understand precisely how family history influences cognition. Finally, we assessed the sensitivity of model parameters to family history controlling for standard neuropsychological test performance. Method Across two experiments, cognitively healthy participants from the Adult Children Study completed an episodic recognition test consisting of high and low frequency words. The diffusion model was applied to decompose accuracy and reaction time into latent parameters which were analyzed as a function of family history. Results In both experiments, individuals with a family history of AD exhibited lower recognition accuracy and this occurred in the absence of an apolipoprotein E (APOE) ε4 allele. The diffusion model revealed this difference was due to changes in the quality of information accumulation (the drift rate) and not differences in response caution or other model parameters. This difference remained after controlling for several standard neuropsychological tests. Conclusions These results confirm that the presence of a family history of AD confers a subtle cognitive deficit in episodic memory as reflected by decreased drift rate that cannot be attributed to APOE. This measure may serve as a novel cognitive marker of preclinical AD. PMID:26192539

Developmental amnesia: a new pattern of dissociation with intact episodic memory.

PubMed

Temple, Christine M; Richardson, Paul

2004-01-01

A case of developmental amnesia is reported for a child, CL, of normal intelligence, who has intact episodic memory but impaired semantic memory for both semantic knowledge of facts and semantic knowledge of words, including general world knowledge, knowledge of word meanings and superordinate knowledge of words. In contrast to the deficits in semantic memory, there are no impairments in episodic memory for verbal or visual material, assessed by recall or recognition. Lexical decision was also intact, indicating impairment in semantic knowledge of vocabulary rather than absence of lexical representations. The case forms a double dissociation to the cases of Vargha-Khadem et al. [Science 277 (1997) 376; Episodic memory: new directions in research (2002) 153]; Gadian et al. [Brain 123 (2000) 499] for whom semantic memory was intact but episodic memory was impaired. This double dissociation suggests that semantic memory and episodic memory have the capacity to develop separately and supports models of modularity within memory development and a functional architecture for the developmental disorders within which there is residual normality rather than pervasive abnormality. Knowledge of arithmetical facts is also spared for CL, consistent with adult studies arguing for numeracy knowledge distinct from other semantics. Reading was characterised by difficulty with irregular words and homophones but intact reading of nonwords. CL has surface dyslexia with poor lexico-semantic reading skills but good phonological reading skills. The case was identified following screening from a population of normal schoolchildren suggesting that developmental amnesias may be more pervasive than has been recognised previously.

Memory strength and specificity revealed by pupillometry

PubMed Central

Papesh, Megan H.; Goldinger, Stephen D.; Hout, Michael C.

2011-01-01

Voice-specificity effects in recognition memory were investigated using both behavioral data and pupillometry. Volunteers initially heard spoken words and nonwords in two voices; they later provided confidence-based old/new classifications to items presented in their original voices, changed (but familiar) voices, or entirely new voices. Recognition was more accurate for old-voice items, replicating prior research. Pupillometry was used to gauge cognitive demand during both encoding and testing: Enlarged pupils revealed that participants devoted greater effort to encoding items that were subsequently recognized. Further, pupil responses were sensitive to the cue match between encoding and retrieval voices, as well as memory strength. Strong memories, and those with the closest encoding-retrieval voice matches, resulted in the highest peak pupil diameters. The results are discussed with respect to episodic memory models and Whittlesea’s (1997) SCAPE framework for recognition memory. PMID:22019480

Dissociable effects of surprising rewards on learning and memory.

PubMed

Rouhani, Nina; Norman, Kenneth A; Niv, Yael

2018-03-19

Reward-prediction errors track the extent to which rewards deviate from expectations, and aid in learning. How do such errors in prediction interact with memory for the rewarding episode? Existing findings point to both cooperative and competitive interactions between learning and memory mechanisms. Here, we investigated whether learning about rewards in a high-risk context, with frequent, large prediction errors, would give rise to higher fidelity memory traces for rewarding events than learning in a low-risk context. Experiment 1 showed that recognition was better for items associated with larger absolute prediction errors during reward learning. Larger prediction errors also led to higher rates of learning about rewards. Interestingly we did not find a relationship between learning rate for reward and recognition-memory accuracy for items, suggesting that these two effects of prediction errors were caused by separate underlying mechanisms. In Experiment 2, we replicated these results with a longer task that posed stronger memory demands and allowed for more learning. We also showed improved source and sequence memory for items within the high-risk context. In Experiment 3, we controlled for the difficulty of reward learning in the risk environments, again replicating the previous results. Moreover, this control revealed that the high-risk context enhanced item-recognition memory beyond the effect of prediction errors. In summary, our results show that prediction errors boost both episodic item memory and incremental reward learning, but the two effects are likely mediated by distinct underlying systems. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The Effects of Previously Acquired Knowledge on Memory for Textual Information.

ERIC Educational Resources Information Center

Byrd, Mark

1987-01-01

Presented series of biographical passages to young and older adults to examine how semantic memory store of previously acquired knowledge affects ability to retain textual information. Older adults had difficulty in delayed, but not in immediate, recognition condition. Suggests that as older adults' episodic memory deteriorated, they could not…

Embodied Memory Judgments: A Case of Motor Fluency

ERIC Educational Resources Information Center

Yang, Shu-Ju; Gallo, David A.; Beilock, Sian L.

2009-01-01

It is well known that perceptual and conceptual fluency can influence episodic memory judgments. Here, the authors asked whether fluency arising from the motor system also impacts recognition memory. Past research has shown that the perception of letters automatically activates motor programs of typing actions in skilled typists. In this study,…

Hemispheric Differences in the Organization of Memory for Text Ideas

ERIC Educational Resources Information Center

Long, Debra L.; Johns, Clinton L.; Jonathan, Eunike

2012-01-01

The goal of this study was to examine hemispheric asymmetries in episodic memory for discourse. Access to previously comprehended information is essential for mapping incoming information to representations of "who did what to whom" in memory. An item-priming-in-recognition paradigm was used to examine differences in how the hemispheres represent…

Spatial navigation, episodic memory, episodic future thinking, and theory of mind in children with autism spectrum disorder: evidence for impairments in mental simulation?

PubMed Central

Lind, Sophie E.; Bowler, Dermot M.; Raber, Jacob

2014-01-01

This study explored spatial navigation alongside several other cognitive abilities that are thought to share common underlying neurocognitive mechanisms (e.g., the capacity for self-projection, scene construction, or mental simulation), and which we hypothesized may be impaired in autism spectrum disorder (ASD). Twenty intellectually high-functioning children with ASD (with a mean age of ~8 years) were compared to 20 sex, age, IQ, and language ability matched typically developing children on a series of tasks to assess spatial navigation, episodic memory, episodic future thinking (also known as episodic foresight or prospection), theory of mind (ToM), relational memory, and central coherence. This is the first study to explore these abilities concurrently within the same sample. Spatial navigation was assessed using the “memory island” task, which involves finding objects within a realistic, computer simulated, three-dimensional environment. Episodic memory and episodic future thinking were assessed using a past and future event description task. ToM was assessed using the “animations” task, in which children were asked to describe the interactions between two animated triangles. Relational memory was assessed using a recognition task involving memory for items (line drawings), patterned backgrounds, or combinations of items and backgrounds. Central coherence was assessed by exploring differences in performance across segmented and unsegmented versions of block design. Children with ASD were found to show impairments in spatial navigation, episodic memory, episodic future thinking, and central coherence, but not ToM or relational memory. Among children with ASD, spatial navigation was found to be significantly negatively related to the number of repetitive behaviors. In other words, children who showed more repetitive behaviors showed poorer spatial navigation. The theoretical and practical implications of the results are discussed. PMID:25538661

Spatial navigation, episodic memory, episodic future thinking, and theory of mind in children with autism spectrum disorder: evidence for impairments in mental simulation?

PubMed

Lind, Sophie E; Bowler, Dermot M; Raber, Jacob

2014-01-01

This study explored spatial navigation alongside several other cognitive abilities that are thought to share common underlying neurocognitive mechanisms (e.g., the capacity for self-projection, scene construction, or mental simulation), and which we hypothesized may be impaired in autism spectrum disorder (ASD). Twenty intellectually high-functioning children with ASD (with a mean age of ~8 years) were compared to 20 sex, age, IQ, and language ability matched typically developing children on a series of tasks to assess spatial navigation, episodic memory, episodic future thinking (also known as episodic foresight or prospection), theory of mind (ToM), relational memory, and central coherence. This is the first study to explore these abilities concurrently within the same sample. Spatial navigation was assessed using the "memory island" task, which involves finding objects within a realistic, computer simulated, three-dimensional environment. Episodic memory and episodic future thinking were assessed using a past and future event description task. ToM was assessed using the "animations" task, in which children were asked to describe the interactions between two animated triangles. Relational memory was assessed using a recognition task involving memory for items (line drawings), patterned backgrounds, or combinations of items and backgrounds. Central coherence was assessed by exploring differences in performance across segmented and unsegmented versions of block design. Children with ASD were found to show impairments in spatial navigation, episodic memory, episodic future thinking, and central coherence, but not ToM or relational memory. Among children with ASD, spatial navigation was found to be significantly negatively related to the number of repetitive behaviors. In other words, children who showed more repetitive behaviors showed poorer spatial navigation. The theoretical and practical implications of the results are discussed.

Impaired event memory and recollection in a case of developmental amnesia.

PubMed

Rosenbaum, R S; Carson, N; Abraham, N; Bowles, B; Kwan, D; Köhler, S; Svoboda, E; Levine, B; Richards, B

2011-10-01

A current debate in the literature is whether all declarative memories and associated memory processes rely on the same neural substrate. Here, we show that H.C., a developmental amnesic person with selective bilateral hippocampal volume loss, has a mild deficit in personal episodic memory, and a more pronounced deficit in public event memory; semantic memory for personal and general knowledge was unimpaired. This was accompanied by a subtle difference in impairment between recollection and familiarity on lab-based tests of recognition memory. Strikingly, H.C.'s recognition did not benefit from a levels-of-processing manipulation. Thus, not all types of declarative memory and related processes can exist independently of the hippocampus even if it is damaged early in life.

Longitudinal patterns of semantic and episodic memory in frontotemporal lobar degeneration and Alzheimer's disease.

PubMed

Xie, Sharon X; Libon, David J; Wang, Xingmei; Massimo, Lauren; Moore, Peachie; Vesely, Luisa; Khan, Alea; Chatterjee, Anjan; Coslett, H Branch; Hurtig, Howard I; Liang, Tsao-Wei; Grossman, Murray

2010-03-01

The longitudinal assessment of episodic and semantic memory was obtained from 236 patients diagnosed with Alzheimer's disease (AD, n = 128) and with frontotemporal lobar degeneration (FTLD, n = 108), including patients with a social comportment/dysexecutive (SOC/EXEC) disorder, progressive nonfluent aphasia (PNFA), semantic dementia (SemD), and corticobasal syndrome (CBS). At the initial assessment, AD patients obtained a lower score on the delayed free recall test than other patients. Longitudinal analyses for delayed free recall found converging performance, with all patients reaching the same level of impairment as AD patients. On the initial evaluation for delayed recognition, AD patients also obtained lower scores than other groups. Longitudinal analyses for delayed recognition test performance found that AD patients consistently produced lower scores than other groups and no convergence between AD and other dementia groups was seen. For semantic memory, there were no initial between-group differences. However, longitudinal analyses for semantic memory revealed group differences over illness duration, with worse performance for SemD versus AD, PNFA, SOC/EXEC, and CBS patients. These data suggest the presence of specific longitudinal patterns of impairment for episodic and semantic memory in AD and FTLD patients suggesting that all forms of dementia do not necessarily converge into a single phenotype.

Episodic memory function is associated with multiple measures of white matter integrity in cognitive aging

PubMed Central

Lockhart, Samuel N.; Mayda, Adriane B. V.; Roach, Alexandra E.; Fletcher, Evan; Carmichael, Owen; Maillard, Pauline; Schwarz, Christopher G.; Yonelinas, Andrew P.; Ranganath, Charan; DeCarli, Charles

2011-01-01

Previous neuroimaging research indicates that white matter injury and integrity, measured respectively by white matter hyperintensities (WMH) and fractional anisotropy (FA) obtained from diffusion tensor imaging (DTI), differ with aging and cerebrovascular disease (CVD) and are associated with episodic memory deficits in cognitively normal older adults. However, knowledge about tract-specific relationships between WMH, FA, and episodic memory in aging remains limited. We hypothesized that white matter connections between frontal cortex and subcortical structures as well as connections between frontal and temporo-parietal cortex would be most affected. In the current study, we examined relationships between WMH, FA and episodic memory in 15 young adults, 13 elders with minimal WMH and 15 elders with extensive WMH, using an episodic recognition memory test for object-color associations. Voxel-based statistics were used to identify voxel clusters where white matter measures were specifically associated with variations in episodic memory performance, and white matter tracts intersecting these clusters were analyzed to examine white matter-memory relationships. White matter injury and integrity measures were significantly associated with episodic memory in extensive regions of white matter, located predominantly in frontal, parietal, and subcortical regions. Template based tractography indicated that white matter injury, as measured by WMH, in the uncinate and inferior longitudinal fasciculi were significantly negatively associated with episodic memory performance. Other tracts such as thalamo-frontal projections, superior longitudinal fasciculus, and dorsal cingulum bundle demonstrated strong negative associations as well. The results suggest that white matter injury to multiple pathways, including connections of frontal and temporal cortex and frontal-subcortical white matter tracts, plays a critical role in memory differences seen in older individuals. PMID:22438841

Orienting to face expression during encoding improves men's recognition of own gender faces.

PubMed

Fulton, Erika K; Bulluck, Megan; Hertzog, Christopher

2015-10-01

It is unclear why women have superior episodic memory of faces, but the benefit may be partially the result of women engaging in superior processing of facial expressions. Therefore, we hypothesized that orienting instructions to attend to facial expression at encoding would significantly improve men's memory of faces and possibly reduce gender differences. We directed 203 college students (122 women) to study 120 faces under instructions to orient to either the person's gender or their emotional expression. They later took a recognition test of these faces by either judging whether they had previously studied the same person or that person with the exact same expression; the latter test evaluated recollection of specific facial details. Orienting to facial expressions during encoding significantly improved men's recognition of own-gender faces and eliminated the advantage that women had for male faces under gender orienting instructions. Although gender differences in spontaneous strategy use when orienting to faces cannot fully account for gender differences in face recognition, orienting men to facial expression during encoding is one way to significantly improve their episodic memory for male faces. Copyright © 2015 Elsevier B.V. All rights reserved.

Type 2 diabetes and impaired glucose tolerance are associated with word memory source monitoring recollection deficits but not simple recognition familiarity deficits following water, low glycaemic load, and high glycaemic load breakfasts.

PubMed

Lamport, Daniel J; Lawton, Clare L; Mansfield, Michael W; Moulin, Chris A J; Dye, Louise

2014-01-30

It has been established that type 2 diabetes, and to some extent, impaired glucose tolerance (IGT), are associated with general neuropsychological impairments in episodic memory. However, the effect of abnormalities in glucose metabolism on specific retrieval processes such as source monitoring has not been investigated. The primary aim was to investigate the impact of type 2 diabetes and IGT on simple word recognition (familiarity) and complex source monitoring (recollection). A secondary aim was to examine the effect of acute breakfast glycaemic load manipulations on episodic memory. Data are presented from two separate studies; (i) 24 adults with type 2 diabetes and 12 controls aged 45-75years, (ii) 18 females with IGT and 47 female controls aged 30-50years. Controls were matched for age, IQ, BMI, waist circumference, and depression. Recognition of previously learned words and memory for specifically which list a previously learned word had appeared in (source monitoring) was examined at two test sessions during the morning after consumption of low glycaemic load, high glycaemic load and water breakfasts according to a counterbalanced, crossover design. Type 2 diabetes (p<0.05) and IGT (p<0.01) were associated with significant source monitoring recollection deficits but not impairments in familiarity. Impairments were only observed in the late postprandial stage at the second test session. These impairments were not attenuated by the breakfast glycaemic load manipulations. Isolated source monitoring recollection deficits indicate that abnormalities in glucose metabolism are not detrimental for global episodic memory processes. This enhances our understanding of how metabolic disorders are associated with memory impairments. © 2013.

Examining ERP correlates of recognition memory: Evidence of accurate source recognition without recollection

PubMed Central

Addante, Richard, J.; Ranganath, Charan; Yonelinas, Andrew, P.

2012-01-01

Recollection is typically associated with high recognition confidence and accurate source memory. However, subjects sometimes make accurate source memory judgments even for items that are not confidently recognized, and it is not known whether these responses are based on recollection or some other memory process. In the current study, we measured event related potentials (ERPs) while subjects made item and source memory confidence judgments in order to determine whether recollection supported accurate source recognition responses for items that were not confidently recognized. In line with previous studies, we found that recognition memory was associated with two ERP effects: an early on-setting FN400 effect, and a later parietal old-new effect [Late Positive Component (LPC)], which have been associated with familiarity and recollection, respectively. The FN400 increased gradually with item recognition confidence, whereas the LPC was only observed for highly confident recognition responses. The LPC was also related to source accuracy, but only for items that had received a high confidence item recognition response; accurate source judgments to items that were less confidently recognized did not exhibit the typical ERP correlate of recollection or familiarity, but rather showed a late, broadly distributed negative ERP difference. The results indicate that accurate source judgments of episodic context can occur even when recollection fails. PMID:22548808

Neural Correlates of Verbal Episodic Memory and Lexical Retrieval in Logopenic Variant Primary Progressive Aphasia.

PubMed

Win, Khaing T; Pluta, John; Yushkevich, Paul; Irwin, David J; McMillan, Corey T; Rascovsky, Katya; Wolk, David; Grossman, Murray

2017-01-01

Objective: Logopenic variant primary progressive aphasia (lvPPA) is commonly associated with Alzheimer's disease (AD) pathology. But lvPPA patients display different cognitive and anatomical profile from the common clinical AD patients, whose verbal episodic memory is primarily affected. Reports of verbal episodic memory difficulty in lvPPA are inconsistent, and we hypothesized that their lexical retrieval impairment contributes to verbal episodic memory performance and is associated with left middle temporal gyrus atrophy. Methods: We evaluated patients with lvPPA ( n = 12) displaying prominent word-finding and repetition difficulties, and a demographically-matched cohort of clinical Alzheimer's disease (AD, n = 26), and healthy seniors ( n = 16). We assessed lexical retrieval with confrontation naming and verbal episodic memory with delayed free recall. Whole-brain regressions related naming and delayed free recall to gray matter atrophy. Medial temporal lobe (MTL) subfields were examined using high in-plane resolution imaging. Results: lvPPA patients had naming and delayed free recall impairments, but intact recognition memory. In lvPPA, delayed free recall was related to naming; both were associated with left middle temporal gyrus atrophy but not MTL atrophy. Despite cerebrospinal fluid evidence consistent with AD pathology, examination of MTL subfields revealed no atrophy in lvPPA. While AD patients displayed impaired delayed free recall, this deficit did not correlate with naming. Regression analyses related delayed free recall deficits in clinical AD patients to MTL subfield atrophy, and naming to left middle temporal gyrus atrophy. Conclusion: Unlike amnestic AD patients, MTL subfields were not affected in lvPPA patients. Verbal episodic memory deficit observed in lvPPA was unlikely to be due to a hippocampal-mediated mechanism but appeared to be due to poor lexical retrieval. Relative sparing of MTL volume and intact recognition memory are consistent with previous reports of hippocampal-sparing variant cases of AD pathology, where neurofibrillary tangles are disproportionately distributed in cortical areas with relative sparing of the hippocampus. This suggests that AD neuropathology in lvPPA may originate in neuronal networks outside of the MTL, which deviates from the typical Braak staging pattern of spreading pathology in clinical AD.

Parietal cortex and episodic memory retrieval in schizophrenia.

PubMed

Lepage, Martin; Pelletier, Marc; Achim, Amélie; Montoya, Alonso; Menear, Matthew; Lal, Sam

2010-06-30

People with schizophrenia consistently show memory impairment on varying tasks including item recognition memory. Relative to the correct rejection of distracter items, the correct recognition of studied items consistently produces an effect termed the old/new effect that is characterized by increased activity in parietal and frontal cortical regions. This effect has received only scant attention in schizophrenia. We examined the old/new effect in 15 people with schizophrenia and 18 controls during an item recognition test, and neural activity was examined with event-related functional magnetic resonance imaging. Both groups performed equally well during the recognition test and showed increased activity in a left dorsolateral prefrontal region and in the precuneus bilaterally during the successful recognition of old items relative to the correct rejection of new items. The control group also exhibited increased activity in the dorsal left parietal cortex. This region has been implicated in the top-down modulation of memory which involves control processes that support memory-retrieval search, monitoring and verification. Although these processes may not be of paramount importance in item recognition memory performance, the present findings suggest that people with schizophrenia may have difficulty with such top-down modulation, a finding consistent with many other studies in information processing.

Neuropsychological and FDG-PET profiles in VGKC autoimmune limbic encephalitis.

PubMed

Dodich, Alessandra; Cerami, Chiara; Iannaccone, Sandro; Marcone, Alessandra; Alongi, Pierpaolo; Crespi, Chiara; Canessa, Nicola; Andreetta, Francesca; Falini, Andrea; Cappa, Stefano F; Perani, Daniela

2016-10-01

Limbic encephalitis (LE) is characterized by an acute or subacute onset with memory impairments, confusional state, behavioral disorders, variably associated with seizures and dystonic movements. It is due to inflammatory processes that selectively affect the medial temporal lobe structures. Voltage-gate potassium channel (VGKC) autoantibodies are frequently observed. In this study, we assessed at the individual level FDG-PET brain metabolic dysfunctions and neuropsychological profiles in three autoimmune LE cases seropositive for neuronal VGKC-complex autoantibodies. LGI1 and CASPR2 potassium channel complex autoantibody subtyping was performed. Cognitive abilities were evaluated with an in-depth neuropsychological battery focused on episodic memory and affective recognition/processing skills. FDG-PET data were analyzed at single-subject level according to a standardized and validated voxel-based Statistical Parametric Mapping (SPM) method. Patients showed severe episodic memory and fear recognition deficits at the neuropsychological assessment. No disorder of mentalizing processing was present. Variable patterns of increases and decreases of brain glucose metabolism emerged in the limbic structures, highlighting the pathology-driven selective vulnerability of this system. Additional involvement of cortical and subcortical regions, particularly in the sensorimotor system and basal ganglia, was found. Episodic memory and fear recognition deficits characterize the cognitive profile of LE. Commonalities and differences may occur in the brain metabolic patterns. Single-subject voxel-based analysis of FDG-PET imaging could be useful in the early detection of the metabolic correlates of cognitive and non-cognitive deficits characterizing LE condition. Copyright © 2016 Elsevier Inc. All rights reserved.

Content-Specific Source Encoding in the Human Medial Temporal Lobe

ERIC Educational Resources Information Center

Awipi, T.; Davachi, L.

2008-01-01

Although the medial temporal lobe (MTL) is known to be essential for episodic encoding, the contributions of individual MTL subregions remain unclear. Data from recognition memory studies have provided evidence that the hippocampus supports relational encoding important for later episodic recollection, whereas the perirhinal cortex has been linked…

Episodic memory for natural and transformed food.

PubMed

Aiello, Marilena; Vignando, Miriam; Foroni, Francesco; Pergola, Giulio; Rossi, Paola; Silveri, Maria Caterina; Rumiati, Raffaella I

2018-05-10

It has been proposed that the conceptual knowledge of food and its putative subdivision into natural (i.e., fruit/vegetables) and transformed (i.e., food that underwent thermic or non-thermic processing) may follow the living/non-living distinction. In the present study, we investigated whether the advantage for living things compared to non-living things observed in episodic memory (the so-called animacy effect) extends to natural foods and transformed foods respectively. We pursued this issue in two experiments. In Experiment 1, we measured episodic memory for natural and transformed foods in young participants. In Experiment 2, we enrolled dementia-free centenarians, patients with Alzheimer's disease (DAT), Progressive primary aphasia (PPA), and healthy controls whose episodic memory was also tested for living/non-living things. Results showed that young participants had better recognition memory for transformed foods compared to natural foods. This difference disappeared in centenarians and patients. However, centenarians and PPA exhibited enhanced levels of false alarms (FA) with natural food, and DAT patients with both natural and transformed food. As far as the living/non-living distinction is concerned, the episodic memory for the living category appears more resilient to the decline compared to the non-living category in patients, particularly those with PPA. In conclusion, our study shows that transformed food is better remembered than natural food, suggesting that it is more salient and possibly relevant from an evolutionary perspective. The natural/transformed distinction appears susceptible to erosion only in the presence of a high degree of episodic memory impairment. These results offer novel insight on episodic memory of food, and also extend the current knowledge on the animacy effect in episodic memory. Copyright © 2018 Elsevier Ltd. All rights reserved.

Neural Correlates of Confidence during Item Recognition and Source Memory Retrieval: Evidence for Both Dual-Process and Strength Memory Theories

ERIC Educational Resources Information Center

Hayes, Scott M.; Buchler, Norbou; Stokes, Jared; Kragel, James; Cabeza, Roberto

2011-01-01

Although the medial-temporal lobes (MTL), PFC, and parietal cortex are considered primary nodes in the episodic memory network, there is much debate regarding the contributions of MTL, PFC, and parietal subregions to recollection versus familiarity (dual-process theory) and the feasibility of accounts on the basis of a single memory strength…

Benefits of computer-based memory and attention training in healthy older adults.

PubMed

Chambon, Caroline; Herrera, Cathy; Romaiguere, Patricia; Paban, Véronique; Alescio-Lautier, Béatrice

2014-09-01

Multifactorial cognitive training programs have a positive effect on cognition in healthy older adults. Among the age-sensitive cognitive domains, episodic memory is the most affected. In the present study, we evaluated the benefits on episodic memory of a computer-based memory and attention training. We targeted consciously controlled processes at encoding and minimizing processing at retrieval, by using more familiarity than recollection during recognition. Such an approach emphasizes processing at encoding and prevents subjects from reinforcing their own errors. Results showed that the training improved recognition performances and induced near transfer to recall. The largest benefits, however, were for tasks with high mental load. Improvement in free recall depended on the modality to recall; semantic recall was improved but not spatial recall. In addition, a far transfer was also observed with better memory self-perception and self-esteem of the participants. Finally, at 6-month follow up, maintenance of benefits was observed only for semantic free recall. The challenge now is to corroborate far transfer by objective measures of everyday life executive functioning. PsycINFO Database Record (c) 2014 APA, all rights reserved.

False Recognition in Behavioral Variant Frontotemporal Dementia and Alzheimer's Disease-Disinhibition or Amnesia?

PubMed

Flanagan, Emma C; Wong, Stephanie; Dutt, Aparna; Tu, Sicong; Bertoux, Maxime; Irish, Muireann; Piguet, Olivier; Rao, Sulakshana; Hodges, John R; Ghosh, Amitabha; Hornberger, Michael

2016-01-01

Episodic memory recall processes in Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) can be similarly impaired, whereas recognition performance is more variable. A potential reason for this variability could be false-positive errors made on recognition trials and whether these errors are due to amnesia per se or a general over-endorsement of recognition items regardless of memory. The current study addressed this issue by analysing recognition performance on the Rey Auditory Verbal Learning Test (RAVLT) in 39 bvFTD, 77 AD and 61 control participants from two centers (India, Australia), as well as disinhibition assessed using the Hayling test. Whereas both AD and bvFTD patients were comparably impaired on delayed recall, bvFTD patients showed intact recognition performance in terms of the number of correct hits. However, both patient groups endorsed significantly more false-positives than controls, and bvFTD and AD patients scored equally poorly on a sensitivity index (correct hits-false-positives). Furthermore, measures of disinhibition were significantly associated with false positives in both groups, with a stronger relationship with false-positives in bvFTD. Voxel-based morphometry analyses revealed similar neural correlates of false positive endorsement across bvFTD and AD, with both patient groups showing involvement of prefrontal and Papez circuitry regions, such as medial temporal and thalamic regions, and a DTI analysis detected an emerging but non-significant trend between false positives and decreased fornix integrity in bvFTD only. These findings suggest that false-positive errors on recognition tests relate to similar mechanisms in bvFTD and AD, reflecting deficits in episodic memory processes and disinhibition. These findings highlight that current memory tests are not sufficient to accurately distinguish between bvFTD and AD patients.

Incidental Context Information Increases Recollection

ERIC Educational Resources Information Center

Ameen-Ali, Kamar E.; Norman, Liam J.; Eacott, Madeline J.; Easton, Alexander

2017-01-01

The current study describes a receiver-operating characteristic (ROC) task for human participants based on the spontaneous recognition memory paradigms typically used with rodents. Recollection was significantly higher when an object was in the same location and background as at encoding, a combination used to assess episodic-like memory in…

Autobiographical Elaboration Reduces Memory Distortion: Cognitive Operations and the Distinctiveness Heuristic

ERIC Educational Resources Information Center

McDonough, Ian M.; Gallo, David A.

2008-01-01

Retrieval monitoring enhances episodic memory accuracy. For instance, false recognition is reduced when participants base their decisions on more distinctive recollections, a retrieval monitoring process called the distinctiveness heuristic. The experiments reported here tested the hypothesis that autobiographical elaboration during study (i.e.,…

The ERP correlates of self-knowledge: Are assessments of one's past, present, and future traits closer to semantic or episodic memory?

PubMed

Tanguay, Annick N; Benton, Lauren; Romio, Lorenza; Sievers, Carolin; Davidson, Patrick S R; Renoult, Louis

2018-02-01

Self-knowledge concerns one's own preferences and personality. It pertains to the self (similar to episodic memory), yet does not concern events. It is factual (like semantic memory), but also idiosyncratic. For these reasons, it is unclear where self-knowledge might fall on a continuum in relation to semantic and episodic memory. In this study, we aimed to compare the event-related potential (ERP) correlates of self-knowledge to those of semantic and episodic memory, using N400 and Late Positive Component (LPC) as proxies for semantic and episodic processing, respectively. We considered an additional factor: time perspective. Temporally distant selves have been suggested to be more semantic compared to the present self, but thinking about one's past and future selves may also engage episodic memory. Twenty-eight adults answered whether traits (e.g., persistent) were true of most people holding an occupation (e.g., soldiers; semantic memory condition), or true of themselves 5 years ago, in the present, or 5 years from now (past, present, and future self-knowledge conditions). The study ended with an episodic recognition memory task for previously seen traits. Present self-knowledge produced mean LPC amplitudes at posterior parietal sites that fell between semantic and episodic memory. Mean LPC amplitudes for past and future self-knowledge were greater than for semantic memory, and not significantly different from episodic memory. Mean N400 amplitudes for the self-knowledge conditions were smaller than for semantic memory at sagittal sites. However, this N400 effect was not separable from a preceding P200 effect at these same electrode sites. This P200 effect can be interpreted as reflecting the greater emotional salience of self as compared to general knowledge, which may have facilitated semantic processing. Overall, our findings are consistent with a distinction between knowledge of others and self-knowledge, but the closeness of self-knowledge's neural correlates to either semantic or episodic memory appears to depend to some extent on time perspective. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Generalized Quantum Episodic Memory Model.

PubMed

Trueblood, Jennifer S; Hemmer, Pernille

2017-11-01

Recent evidence suggests that experienced events are often mapped to too many episodic states, including those that are logically or experimentally incompatible with one another. For example, episodic over-distribution patterns show that the probability of accepting an item under different mutually exclusive conditions violates the disjunction rule. A related example, called subadditivity, occurs when the probability of accepting an item under mutually exclusive and exhaustive instruction conditions sums to a number >1. Both the over-distribution effect and subadditivity have been widely observed in item and source-memory paradigms. These phenomena are difficult to explain using standard memory frameworks, such as signal-detection theory. A dual-trace model called the over-distribution (OD) model (Brainerd & Reyna, 2008) can explain the episodic over-distribution effect, but not subadditivity. Our goal is to develop a model that can explain both effects. In this paper, we propose the Generalized Quantum Episodic Memory (GQEM) model, which extends the Quantum Episodic Memory (QEM) model developed by Brainerd, Wang, and Reyna (2013). We test GQEM by comparing it to the OD model using data from a novel item-memory experiment and a previously published source-memory experiment (Kellen, Singmann, & Klauer, 2014) examining the over-distribution effect. Using the best-fit parameters from the over-distribution experiments, we conclude by showing that the GQEM model can also account for subadditivity. Overall these results add to a growing body of evidence suggesting that quantum probability theory is a valuable tool in modeling recognition memory. Copyright © 2016 Cognitive Science Society, Inc.

Prospective and retrospective episodic metamemory in posttraumatic stress disorder.

PubMed

Sacher, Mathilde; Tudorache, Andrei-Cristian; Clarys, David; Boudjarane, Mohamed; Landré, Lionel; El-Hage, Wissam

2018-03-14

Posttraumatic stress disorder (PTSD) has been consistently associated with episodic memory deficits. To some extent, these deficits could be related to an impairment of metamemory in individuals with PTSD. This research consequently aims at investigating prospective (feeling-of-knowing, FOK) and retrospective (confidence) metamemory judgments for episodic information in PTSD. Twenty participants with PTSD and without depression were compared to 30 healthy comparison participants on metamemory judgments during an episodic memory task. The concordance between metamemory judgments and recognition performance was then assessed by gamma correlations. The results confirmed that PTSD is associated with episodic memory impairment. Regarding metamemory, gamma correlations indicated that participants with PTSD failed to accurately predict their future memory performance as compared to the comparison group (mean FOK gamma correlations: .23 vs. .42, respectively). Furthermore, participants with PTSD made less accurate confidence judgments than comparison participants (mean confidence gamma correlations: .62 vs. .74, respectively). Our results demonstrate an alteration of both prospective and retrospective metamemory processes in PTSD, which could be of particular relevance to future therapeutic interventions focusing on metacognitive strategies.

Internally Generated Reactivation of Single Neurons in Human Hippocampus During Free Recall

PubMed Central

Gelbard-Sagiv, Hagar; Mukamel, Roy; Harel, Michal; Malach, Rafael; Fried, Itzhak

2009-01-01

The emergence of memory, a trace of things past, into human consciousness is one of the greatest mysteries of the human mind. Whereas the neuronal basis of recognition memory can be probed experimentally in human and nonhuman primates, the study of free recall requires that the mind declare the occurrence of a recalled memory (an event intrinsic to the organism and invisible to an observer). Here, we report the activity of single neurons in the human hippocampus and surrounding areas when subjects first view cinematic episodes consisting of audiovisual sequences and again later when they freely recall these episodes. A subset of these neurons exhibited selective firing, which often persisted throughout and following specific episodes for as long as 12 seconds. Verbal reports of memories of these specific episodes at the time of free recall were preceded by selective reactivation of the same hippocampal and entorhinal cortex neurons. We suggest that this reactivation is an internally generated neuronal correlate for the subjective experience of spontaneous emergence of human recollection. PMID:18772395

Confabulation in healthy aging is related to interference of overlearned, semantically similar information on episodic memory recall.

PubMed

Dalla Barba, Gianfranco; Attali, Eve; La Corte, Valentina

2010-07-01

Normal aging is characterized by reduced performance on tasks of long-term memory. Older adults (OA) not only show reduced performance on tasks of recall and recognition memory, but also, compared to young adults (YA), are more vulnerable to memory distortions. In this study we describe the performance of a group of OA and a group of YA on the recall of three different types of story: a previously unknown story, a well-known fairy tale (Sleeping Beauty), and a modified well-known fairy tale (Little Red Riding Hood is not eaten by the wolf). The aim of our study was to test the hypothesis that in OA strongly represented, overlearned information interferes with episodic recall-that is, the retrieval of specific, unique past episodes. OA produced significantly more confabulations than YA and in particular in the recall of the modified fairy tale. Our findings indicate that the interference of strongly represented, overlearned information in episodic memory recall is implicated in the production of confabulations in OA. This effect is particularly prominent when the to-be remembered episodic information shows strong semantic similarities with preexisting, overlearned information.

Multi-modal imaging predicts memory performance in normal aging and cognitive decline.

PubMed

Walhovd, K B; Fjell, A M; Dale, A M; McEvoy, L K; Brewer, J; Karow, D S; Salmon, D P; Fennema-Notestine, C

2010-07-01

This study (n=161) related morphometric MR imaging, FDG-PET and APOE genotype to memory scores in normal controls (NC), mild cognitive impairment (MCI) and Alzheimer's disease (AD). Stepwise regression analyses focused on morphometric and metabolic characteristics of the episodic memory network: hippocampus, entorhinal, parahippocampal, retrosplenial, posterior cingulate, precuneus, inferior parietal, and lateral orbitofrontal cortices. In NC, hippocampal metabolism predicted learning; entorhinal metabolism predicted recognition; and hippocampal metabolism predicted recall. In MCI, thickness of the entorhinal and precuneus cortices predicted learning, while parahippocampal metabolism predicted recognition. In AD, posterior cingulate cortical thickness predicted learning, while APOE genotype predicted recognition. In the total sample, hippocampal volume and metabolism, cortical thickness of the precuneus, and inferior parietal metabolism predicted learning; hippocampal volume and metabolism, parahippocampal thickness and APOE genotype predicted recognition. Imaging methods appear complementary and differentially sensitive to memory in health and disease. Medial temporal and parietal metabolism and morphometry best explained memory variance. Medial temporal characteristics were related to learning, recall and recognition, while parietal structures only predicted learning. Copyright 2008. Published by Elsevier Inc.

Impairments in Component Processes of Executive Function and Episodic Memory in Alcoholism, HIV Infection, and HIV Infection with Alcoholism Comorbidity.

PubMed

Fama, Rosemary; Sullivan, Edith V; Sassoon, Stephanie A; Pfefferbaum, Adolf; Zahr, Natalie M

2016-12-01

Executive functioning and episodic memory impairment occur in HIV infection (HIV) and chronic alcoholism (ALC). Comorbidity of these conditions (HIV + ALC) is prevalent and heightens risk of vulnerability to separate and compounded deficits. Age and disease-related variables can also serve as mediators of cognitive impairment and should be considered, given the extended longevity of HIV-infected individuals in this era of improved pharmacological therapy. HIV, ALC, HIV + ALC, and normal controls (NC) were administered traditional and computerized tests of executive function and episodic memory. Test scores were expressed as age- and education-corrected Z-scores; selective tests were averaged to compute Executive Function and Episodic Memory Composite scores. Efficiency scores were calculated for tests with accuracy and response times. HIV, ALC, and HIV + ALC had lower scores than NC on Executive Function and Episodic Memory Composites, with HIV + ALC even lower than ALC and HIV on the Episodic Memory Composite. Impairments in planning and free recall of visuospatial material were observed in ALC, whereas impairments in psychomotor speed, sequencing, narrative free recall, and pattern recognition were observed in HIV. Lower decision-making efficiency scores than NC occurred in all 3 clinical groups. In ALC, age and lifetime alcohol consumption were each unique predictors of Executive Function and Episodic Memory Composite scores. In HIV + ALC, age was a unique predictor of Episodic Memory Composite score. Disease-specific and disease-overlapping patterns of impairment in HIV, ALC, and HIV + ALC have implications regarding brain systems disrupted by each disease and clinical ramifications regarding the complexities and compounded damping of cognitive functioning associated with dual diagnosis that may be exacerbated with aging. Copyright © 2016 by the Research Society on Alcoholism.

Interference with episodic memory retrieval following transcranial stimulation of the inferior but not the superior parietal lobule.

PubMed

Sestieri, Carlo; Capotosto, Paolo; Tosoni, Annalisa; Luca Romani, Gian; Corbetta, Maurizio

2013-04-01

Although posterior parietal cortex (PPC) has been traditionally associated with spatial attention and sensorimotor functions, recent neuroimaging evidence has suggested the involvement of regions of left PCC (LPPC) in memory retrieval. Yet, the role of the parietal lobe in memory-related functions is still controversial. Here we investigated the causal involvement of different LPPC regions in episodic memory retrieval using repetitive transcranial magnetic stimulation (rTMS) during a task that provided both objective and subjective measures of item recognition and source memory. Stimulation sites were identified on the basis of a recent fMRI study showing the involvement of regions of the default mode network (DMN), such as the angular gyrus (AG) in the inferior parietal lobule (IPL), during search for relevant information in episodic memory, and regions of the dorsal attention network (DAN), such as the superior parietal lobule (SPL), during perceptual search. We predicted a selective disruption of memory performance following rTMS stimulation of the left AG relative to a sham condition or stimulation of the left SPL. We found a modest but significant decrease of sensitivity for item recognition when AG was directly compared to SPL, but not to sham stimulation. A stronger effect was however observed for the criterion of source memory judgments when comparing AG with both SPL and sham stimulation, suggesting that the rTMS over AG affects subjective aspects of source monitoring associated with the weighing of relevant retrieved information for source attribution. Copyright © 2013 Elsevier Ltd. All rights reserved.

General and social cognition in remitted first-episode schizophrenia patients: a comparative study.

PubMed

Caldiroli, Alice; Buoli, Massimiliano; Serati, Marta; Cahn, Wiepke; Altamura, A Carlo

2016-10-01

The aim of this paper was to investigate whether both neurocognitive and social cognitive performances were different between remitted first-episode schizophrenia patients, non-remitters and healthy controls (HC). We assessed social cognition (Degraded Facial Affect Recognition Task-DFAR and Emotional Mentalizing Task-EMT) and neurocognition (Wechsler Adult Intelligence Scale and Word Learning Test-WLT) in 174 remitted first-episode schizophrenia patients, 110 non-remitted first-episode schizophrenia patients and 320 HC. Multivariate analyses of variance with age, gender and IQ as covariates (MANCOVA) were performed to compare mean cognitive test scores between the three groups. Remitted first-episode schizophrenia patients performed significantly worse than HC only in one verbal memory task (WLT immediate recall; p = 0.004); in the same test, they were significantly better than non-remitters (p = 0.027). Non-remitted first-episode schizophrenia patients, differently from remitters, performed significantly worse than HC in terms of social cognition (EMT-p < 0.05 and DFAR-p < 0.05). Remitted first-episode schizophrenia patients presented worse cognitive performance than HC in verbal memory tasks, but not in facial affect recognition and in ToM, while non-remitters did; these results suggest that neurocognitive deficits are the core hallmark of schizophrenia and that social cognition is relatively unaffected in remitted patients after their first episode.

Encoding processes during retrieval tasks.

PubMed

Buckner, R L; Wheeler, M E; Sheridan, M A

2001-04-01

Episodic memory encoding is pervasive across many kinds of task and often arises as a secondary processing effect in tasks that do not require intentional memorization. To illustrate the pervasive nature of information processing that leads to episodic encoding, a form of incidental encoding was explored based on the "Testing" phenomenon: The incidental-encoding task was an episodic memory retrieval task. Behavioral data showed that performing a memory retrieval task was as effective as intentional instructions at promoting episodic encoding. During fMRI imaging, subjects viewed old and new words and indicated whether they remembered them. Relevant to encoding, the fate of the new words was examined using a second, surprise test of recognition after the imaging session. fMRI analysis of those new words that were later remembered revealed greater activity in left frontal regions than those that were later forgotten - the same pattern of results as previously observed for traditional incidental and intentional episodic encoding tasks. This finding may offer a partial explanation for why repeated testing improves memory performance. Furthermore, the observation of correlates of episodic memory encoding during retrieval tasks challenges some interpretations that arise from direct comparisons between "encoding tasks" and "retrieval tasks" in imaging data. Encoding processes and their neural correlates may arise in many tasks, even those nominally labeled as retrieval tasks by the experimenter.

Adapting to Changing Memory Retrieval Demands: Evidence from Event-Related Potentials

ERIC Educational Resources Information Center

Benoit, Roland G.; Werkle-Bergner, Markus; Mecklinger, Axel; Kray, Jutta

2009-01-01

This study investigated preparatory processes involved in adapting to changing episodic memory retrieval demands. Event-related potentials (ERPs) were recorded while participants performed a general old/new recognition task and a specific task that also required retrieval of perceptual details. The relevant task remained either constant or changed…

Odors as effective retrieval cues for stressful episodes.

PubMed

Wiemers, Uta S; Sauvage, Magdalena M; Wolf, Oliver T

2014-07-01

Olfactory information seems to play a special role in memory due to the fast and direct processing of olfactory information in limbic areas like the amygdala and the hippocampus. This has led to the assumption that odors can serve as effective retrieval cues for autobiographic memories, especially emotional memories. The current study sought to investigate whether an olfactory cue can serve as an effective retrieval cue for memories of a stressful episode. A total of 95 participants were exposed to a psychosocial stressor or a well matching but not stressful control condition. During both conditions were visual objects present, either bound to the situation (central objects) or not (peripheral objects). Additionally, an ambient odor was present during both conditions. The next day, participants engaged in an unexpected object recognition task either under the influence of the same odor as was present during encoding (congruent odor) or another odor (non-congruent odor). Results show that stressed participants show a better memory for all objects and especially for central visual objects if recognition took place under influence of the congruent odor. An olfactory cue thus indeed seems to be an effective retrieval cue for stressful memories. Copyright © 2013 Elsevier Inc. All rights reserved.

The late posterior negativity in ERP studies of episodic memory: action monitoring and retrieval of attribute conjunctions.

PubMed

Johansson, Mikael; Mecklinger, Axel

2003-10-01

The focus of the present paper is a late posterior negative slow wave (LPN) that has frequently been reported in event-related potential (ERP) studies of memory. An overview of these studies suggests that two broad classes of experimental conditions tend to elicit this component: (a) item recognition tasks associated with enhanced action monitoring demands arising from response conflict and (b) memory tasks that require the binding of items with contextual information specifying the study episode. A combined stimulus- and response-locked analysis of data from two studies mapping onto these classes allowed a temporal and functional decomposition of the LPN. While only the LPN observed in the item recognition task could be attributed to the involvement of a posteriorly distributed response-locked error-related negativity (or error negativity; ERN/Ne) occurring immediately after the response, the source-memory task was associated with a stimulus-locked negative slow wave occurring prior and during response execution that was evident when data were matched for response latencies. We argue that the presence of the former reflects action monitoring due to high levels of response conflict, whereas the latter reflects retrieval processes that may act to reconstruct the prior study episode when task-relevant attribute conjunctions are not readily recovered or need continued evaluation.

They saw a movie: long-term memory for an extended audiovisual narrative.

PubMed

Furman, Orit; Dorfman, Nimrod; Hasson, Uri; Davachi, Lila; Dudai, Yadin

2007-06-01

We measured long-term memory for a narrative film. During the study session, participants watched a 27-min movie episode, without instructions to remember it. During the test session, administered at a delay ranging from 3 h to 9 mo after the study session, long-term memory for the movie was probed using a computerized questionnaire that assessed cued recall, recognition, and metamemory of movie events sampled approximately 20 sec apart. The performance of each group of participants was measured at a single time point only. The participants remembered many events in the movie even months after watching it. Analysis of performance, using multiple measures, indicates differences between recent (weeks) and remote (months) memory. While high-confidence recognition performance was a reliable index of memory throughout the measured time span, cued recall accuracy was higher for relatively recent information. Analysis of different content elements in the movie revealed differential memory performance profiles according to time since encoding. We also used the data to propose lower limits on the capacity of long-term memory. This experimental paradigm is useful not only for the analysis of behavioral performance that results from encoding episodes in a continuous real-life-like situation, but is also suitable for studying brain substrates and processes of real-life memory using functional brain imaging.

They saw a movie: Long-term memory for an extended audiovisual narrative

PubMed Central

Furman, Orit; Dorfman, Nimrod; Hasson, Uri; Davachi, Lila; Dudai, Yadin

2007-01-01

We measured long-term memory for a narrative film. During the study session, participants watched a 27-min movie episode, without instructions to remember it. During the test session, administered at a delay ranging from 3 h to 9 mo after the study session, long-term memory for the movie was probed using a computerized questionnaire that assessed cued recall, recognition, and metamemory of movie events sampled ∼20 sec apart. The performance of each group of participants was measured at a single time point only. The participants remembered many events in the movie even months after watching it. Analysis of performance, using multiple measures, indicates differences between recent (weeks) and remote (months) memory. While high-confidence recognition performance was a reliable index of memory throughout the measured time span, cued recall accuracy was higher for relatively recent information. Analysis of different content elements in the movie revealed differential memory performance profiles according to time since encoding. We also used the data to propose lower limits on the capacity of long-term memory. This experimental paradigm is useful not only for the analysis of behavioral performance that results from encoding episodes in a continuous real-life-like situation, but is also suitable for studying brain substrates and processes of real-life memory using functional brain imaging. PMID:17562897

Prefrontal Engagement during Source Memory Retrieval Depends on the Prior Encoding Task

PubMed Central

Kuo, Trudy Y.; Van Petten, Cyma

2008-01-01

The prefrontal cortex is strongly engaged by some, but not all, episodic memory tests. Prior work has shown that source recognition tests—those that require memory for conjunctions of studied attributes—yield deficient performance in patients with prefrontal damage and greater prefrontal activity in healthy subjects, as compared to simple recognition tests. Here, we tested the hypothesis that there is no intrinsic relationship between the prefrontal cortex and source memory, but that the prefrontal cortex is engaged by the demand to retrieve weakly encoded relationships. Subjects attempted to remember object/color conjunctions after an encoding task that focused on object identity alone, and an integrative encoding task that encouraged attention to object/color relationships. After the integrative encoding task, the late prefrontal brain electrical activity that typically occurs in source memory tests was eliminated. Earlier brain electrical activity related to successful recognition of the objects was unaffected by the nature of prior encoding. PMID:16839287

Impaired Word and Face Recognition in Older Adults with Type 2 Diabetes.

PubMed

Jones, Nicola; Riby, Leigh M; Smith, Michael A

2016-07-01

Older adults with type 2 diabetes mellitus (DM2) exhibit accelerated decline in some domains of cognition including verbal episodic memory. Few studies have investigated the influence of DM2 status in older adults on recognition memory for more complex stimuli such as faces. In the present study we sought to compare recognition memory performance for words, objects and faces under conditions of relatively low and high cognitive load. Healthy older adults with good glucoregulatory control (n = 13) and older adults with DM2 (n = 24) were administered recognition memory tasks in which stimuli (faces, objects and words) were presented under conditions of either i) low (stimulus presented without a background pattern) or ii) high (stimulus presented against a background pattern) cognitive load. In a subsequent recognition phase, the DM2 group recognized fewer faces than healthy controls. Further, the DM2 group exhibited word recognition deficits in the low cognitive load condition. The recognition memory impairment observed in patients with DM2 has clear implications for day-to-day functioning. Although these deficits were not amplified under conditions of increased cognitive load, the present study emphasizes that recognition memory impairment for both words and more complex stimuli such as face are a feature of DM2 in older adults. Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.

Metamemory monitoring in mild cognitive impairment: Evidence of a less accurate episodic feeling-of-knowing.

PubMed

Perrotin, Audrey; Belleville, Sylvie; Isingrini, Michel

2007-09-20

This study aimed at exploring metamemory and specifically the accuracy of memory monitoring in mild cognitive impairment (MCI) using an episodic memory feeling-of-knowing (FOK) procedure. To this end, 20 people with MCI and 20 matched control participants were compared on the episodic FOK task. Results showed that the MCI group made less accurate FOK predictions than the control group by overestimating their memory performance on a recognition task. The MCI overestimation behavior was found to be critically related to the severity of their cognitive decline. In the light of recent neuroanatomical models showing the involvement of a temporal-frontal network underlying accurate FOK predictions, the role of memory and executive processes was evaluated. Thus, participants were also administered memory and executive neuropsychological tests. Correlation analysis revealed a between-group differential pattern indicating that FOK accuracy was primarily related to memory abilities in people with MCI, whereas it was specifically related to executive functioning in control participants. The lesser ability of people with MCI to assess their memory status accurately on an episodic FOK task is discussed in relation to both their subjective memory complaints and to their actual memory deficits which might be mediated by the brain vulnerability of their hippocampus and medial temporal system. It is suggested that their memory weakness may lead people with MCI to use other less reliable forms of memory monitoring.

[Effects of Ginkgo biloba extract in improving episodic memory of patients with mild cognitive impairment: a randomized controlled trial].

PubMed

Zhao, Ming-xing; Dong, Zhen-hua; Yu, Zhong-hai; Xiao, Shi-yuan; Li, Ya-ming

2012-06-01

Mild cognitive impairment is a transitional stage between normal aging and dementia. It is important in terms of recognizing memory loss in older people as well as identifying a group of individuals at high risk of developing dementia and who may benefit from preventive strategies. Ginkgo biloba extract has been shown to possess polyvalent properties, such as anti-oxidation, anti-apoptosis and anti-inflammation. Ginkgo biloba extract appears to have a neuroprotective effect against neurodegenerative diseases. To observe the efficacy of Ginkgo biloba leaf tablet in improving episodic memory of mild cognitive impairment. This is a multicenter, randomized, controlled trial. The authors enrolled generally healthy, ambulatory or ambulatory-aided amnestic subjects with MCI, 60 to 85 years old, who expressed a memory complaint from Huadong Hospital, seven Community Health Centers in Shanghai, and Shanghai First Welfare Institution. A total of 120 MCI patients were randomly assigned to the Ginkgo biloba leaf tablet group (treatment group, 60 cases) and control group (60 cases). The patients in the treatment group took Ginkgo biloba leaf tablets 3 times a day, 19.2 mg each dose. The control group did not receive any intelligence-promoting or vasodilator reflex treatment except some health care. The patients were tested with nonsense picture recognition of the clinical memory scale and the logical memory test based on the Wechsler memory scale before and after treatment. After 6 months of treatment, the scores of the logical memory test and nonsense picture recognition were increased significantly in the treatment group (P<0.01, P<0.05), while the scores of the two tests from the control group had no statistically significant difference (P>0.05). After treatment, the positive rate of nonsense picture recognition was 55.17% in the treatment group, which was significantly higher than that of the control group at 32.73% (P<0.05). The efficacy rate of logical memory was 58.62% in the treatment group, also higher than 38.18% in the control group (P<0.05). Ginkgo biloba leaf tablet showed good efficacy in promoting episodic memory function in MCI patients.

Visual novel stimuli in an ERP novelty oddball paradigm: effects of familiarity on repetition and recognition memory.

PubMed

Cycowicz, Yael M; Friedman, David

2007-01-01

The orienting response, the brain's reaction to novel and/or out of context familiar events, is reflected by the novelty P3 of the ERP. Contextually novel events also engender high rates of recognition memory. We examined, under incidental and intentional conditions, the effects of visual symbol familiarity on the novelty P3 recorded during an oddball task and on the parietal episodic memory (EM) effect, an index of recollection. Repetition of familiar, but not unfamiliar, symbols elicited a reduction in the novelty P3. Better recognition performance for the familiar symbols was associated with a robust parietal EM effect, which was absent for the unfamiliar symbols in the incidental task. These data demonstrate that processing of novel events depends on expectation and whether stimuli have preexisting representations in long-term semantic memory.

Latency of modality-specific reactivation of auditory and visual information during episodic memory retrieval.

PubMed

Ueno, Daisuke; Masumoto, Kouhei; Sutani, Kouichi; Iwaki, Sunao

2015-04-15

This study used magnetoencephalography (MEG) to examine the latency of modality-specific reactivation in the visual and auditory cortices during a recognition task to determine the effects of reactivation on episodic memory retrieval. Nine right-handed healthy young adults participated in the experiment. The experiment consisted of a word-encoding phase and two recognition phases. Three encoding conditions were included: encoding words alone (word-only) and encoding words presented with either related pictures (visual) or related sounds (auditory). The recognition task was conducted in the MEG scanner 15 min after the completion of the encoding phase. After the recognition test, a source-recognition task was given, in which participants were required to choose whether each recognition word was not presented or was presented with which information during the encoding phase. Word recognition in the auditory condition was higher than that in the word-only condition. Confidence-of-recognition scores (d') and the source-recognition test showed superior performance in both the visual and the auditory conditions compared with the word-only condition. An equivalent current dipoles analysis of MEG data indicated that higher equivalent current dipole amplitudes in the right fusiform gyrus occurred during the visual condition and in the superior temporal auditory cortices during the auditory condition, both 450-550 ms after onset of the recognition stimuli. Results suggest that reactivation of visual and auditory brain regions during recognition binds language with modality-specific information and that reactivation enhances confidence in one's recognition performance.

Donepezil improves episodic memory in young individuals vulnerable to the effects of sleep deprivation.

PubMed

Chuah, Lisa Y M; Chong, Delise L; Chen, Annette K; Rekshan, William R; Tan, Jiat-Chow; Zheng, Hui; Chee, Michael W L

2009-08-01

We investigated if donepezil, a long-acting orally administered cholinesterase inhibitor, would reduce episodic memory deficits associated with 24 h of sleep deprivation. Double-blind, placebo-controlled, crossover study involving 7 laboratory visits over 2 months. Participants underwent 4 functional MRI scans; 2 sessions (donepezil or placebo) followed a normal night's sleep, and 2 sessions followed a night of sleep deprivation. The study took place in a research laboratory. 26 young, healthy volunteers with no history of any sleep, psychiatric, or neurologic disorders. 5 mg of donepezil was taken once daily for approximately 17 days. Subjects were scanned while performing a semantic judgment task and tested for word recognition outside the scanner 45 minutes later. Sleep deprivation increased the frequency of non-responses at encoding and impaired delayed recognition. No benefit of donepezil was evident when participants were well rested. When sleep deprived, individuals who showed greater performance decline improved with donepezil, whereas more resistant individuals did not benefit. Accompanying these behavioral effects, there was corresponding modulation of task-related activation in functionally relevant brain regions. Brain regions identified in relation to donepezil-induced alteration in non-response rates could be distinguished from regions relating to improved recognition memory. This suggests that donepezil can improve delayed recognition in sleep-deprived persons by improving attention as well as enhancing memory encoding. Donepezil reduced decline in recognition performance in individuals vulnerable to the effects of sleep deprivation. Additionally, our findings demonstrate the utility of combined fMRI-behavior evaluation in psychopharmacological studies.

Cognitive and behavioral evaluation of nutritional interventions in rodent models of brain aging and dementia

PubMed Central

Wahl, Devin; Coogan, Sean CP; Solon-Biet, Samantha M; de Cabo, Rafael; Haran, James B; Raubenheimer, David; Cogger, Victoria C; Mattson, Mark P; Simpson, Stephen J; Le Couteur, David G

2017-01-01

Evaluation of behavior and cognition in rodent models underpins mechanistic and interventional studies of brain aging and neurodegenerative diseases, especially dementia. Commonly used tests include Morris water maze, Barnes maze, object recognition, fear conditioning, radial arm water maze, and Y maze. Each of these tests reflects some aspects of human memory including episodic memory, recognition memory, semantic memory, spatial memory, and emotional memory. Although most interventional studies in rodent models of dementia have focused on pharmacological agents, there are an increasing number of studies that have evaluated nutritional interventions including caloric restriction, intermittent fasting, and manipulation of macronutrients. Dietary interventions have been shown to influence various cognitive and behavioral tests in rodents indicating that nutrition can influence brain aging and possibly neurodegeneration. PMID:28932108

Associative Information in Memory: Evidence from Cued Recall

ERIC Educational Resources Information Center

Aue, William R.; Criss, Amy H.; Fischetti, Nicholas W.

2012-01-01

The representation of item and associative information in episodic memory was investigated using cued recall and single item recognition. In the first four experiments, participants studied two lists constructed such that some items presented in a pair during List 1 were rearranged to create new pairs in List 2 and were accompanied by pairs…

Dietary effects on object recognition: The impact of high-fat high-sugar diets on recollection and familiarity-based memory.

PubMed

Tran, Dominic M D; Westbrook, R Frederick

2018-05-31

Exposure to a high-fat high-sugar (HFHS) diet rapidly impairs novel-place- but not novel-object-recognition memory in rats (Tran & Westbrook, 2015, 2017). Three experiments sought to investigate the generality of diet-induced cognitive deficits by examining whether there are conditions under which object-recognition memory is impaired. Experiments 1 and 3 tested the strength of short- and long-term object-memory trace, respectively, by varying the interval of time between object familiarization and subsequent novel object test. Experiment 2 tested the effect of increasing working memory load on object-recognition memory by interleaving additional object exposures between familiarization and test in an n-back style task. Experiments 1-3 failed to detect any differences in object recognition between HFHS and control rats. Experiment 4 controlled for object novelty by separately familiarizing both objects presented at test, which included one remote-familiar and one recent-familiar object. Under these conditions, when test objects differed in their relative recency, HFHS rats showed a weaker memory trace for the remote object compared to chow rats. This result suggests that the diet leaves intact recollection judgments, but impairs familiarity judgments. We speculate that the HFHS diet adversely affects "where" memories as well as the quality of "what" memories, and discuss these effects in relation to recollection and familiarity memory models, hippocampal-dependent functions, and episodic food memories. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

[Unexpected outings of Alzheimer patients living in retirement homes: Therapeutic perspectives].

PubMed

Brossard, F; Caron, R

2016-10-01

Various behavior disorders can occur during Alzheimer's disease, in particular unexpected outings. This article aims at understanding the diverse mechanisms present during a "runaway" episode, which can manifest in an acute way. The authors bring to light through clinical examples what is at work from a psychological perspective in order to create new accompaniment methods. First, the authors reviewed the literature on runaway episodes in order to point out necessary themes for reflection. Then, from a Freudian theoretical model, they brought to light four fundamental mechanisms: hallucinations, false recognition, non-recognition, and recognition. These are mainly, although not exhaustively, understood from perceptions, memory-traces, indications of quality, and memories. This theory was questioned by means of presented clinical cases. Various post-Freudian models allowed the authors to emphasize the pathological experience in the role of perceptions and the functions, which come into play in the psychic economy. By going back and forth between theory and clinical cases, the authors underline the importance of perception in the phenomenon of unexpected outings. Finally, the Lacanian psychoanalytical theories provide a framework to question clinical cases but also provide answers to the criticisms found in the diverse reserved models. Through this study the authors hypothesize that the runaway episodes are not senseless but result from the interaction between the effects of the brain damage and the anxiety, which they arouse in the subjectivity of the person suffering from Alzheimer's. Leaning on false-recognitions, hallucinations, and non-recognitions such as were described in "Project for a scientific psychology", the authors put forward the hypothesis that these mechanisms express themselves in an imaginary relation, as in psychosis. The question of whether the runaway episodes of Alzheimer's sufferers can be classified as psychotic breakouts with a loss of touch with reality, or if the runaway episodes could be prevented by offering enough reassurance and support, is open to further debate. Copyright © 2016. Published by Elsevier Masson SAS.

Recognition memory: a review of the critical findings and an integrated theory for relating them.

PubMed

Malmberg, Kenneth J

2008-12-01

The development of formal models has aided theoretical progress in recognition memory research. Here, I review the findings that are critical for testing them, including behavioral and brain imaging results of single-item recognition, plurality discrimination, and associative recognition experiments under a variety of testing conditions. I also review the major approaches to measurement and process modeling of recognition. The review indicates that several extant dual-process measures of recollection are unreliable, and thus they are unsuitable as a basis for forming strong conclusions. At the process level, however, the retrieval dynamics of recognition memory and the effect of strengthening operations suggest that a recall-to-reject process plays an important role in plurality discrimination and associative recognition, but not necessarily in single-item recognition. A new theoretical framework proposes that the contribution of recollection to recognition depends on whether the retrieval of episodic details improves accuracy, and it organizes the models around the construct of efficiency. Accordingly, subjects adopt strategies that they believe will produce a desired level of accuracy in the shortest amount of time. Several models derived from this framework are shown to account the accuracy, latency, and confidence with which the various recognition tasks are performed.

The Effects of an Afternoon Nap on Episodic Memory in Young and Older Adults

PubMed Central

Fairley, Jacqueline; Decker, Michael J.; Bliwise, Donald L.

2017-01-01

Abstract Study Objectives: In young adults, napping is hypothesized to benefit episodic memory retention (eg, via consolidation). Whether this relationship is present in older adults has not been adequately tested but is an important question because older adults display marked changes in sleep and memory. Design: Between-subjects design. Setting: Sleep laboratory at Emory University School of Medicine. Participants: Fifty healthy young adults (18–29) and 45 community-dwelling older adults (58–83). Intervention: Participants were randomly assigned to a 90-minute nap opportunity or an equal interval of quiet wakefulness. Measurements and Results: Participants underwent an item-wise directed forgetting learning procedure in which they studied words that were individually followed by the instruction to “remember” or “forget.” Following a 90-minute retention interval filled with quiet wakefulness or a nap opportunity, they were asked to free recall and recognize those words. Young adults retained significantly more words following a nap interval than a quiet wakefulness interval on both free recall and recognition tests. There was modest evidence for greater nap-related retention of “remember” items relative to “forget” items for free recall but not recognition. Older adults’ memory retention did not differ across nap and quiet wakefulness conditions, although they demonstrated greater fragmentation, lower N3, and lower rapid eye movement duration than the young adults. Conclusions: In young adults, an afternoon nap benefits episodic memory retention, but such benefits decrease with advancing age. PMID:28329381

Chronic treatment with sulbutiamine improves memory in an object recognition task and reduces some amnesic effects of dizocilpine in a spatial delayed-non-match-to-sample task.

PubMed

Bizot, Jean-Charles; Herpin, Alexandre; Pothion, Stéphanie; Pirot, Sylvain; Trovero, Fabrice; Ollat, Hélène

2005-07-01

The effect of a sulbutiamine chronic treatment on memory was studied in rats with a spatial delayed-non-match-to-sample (DNMTS) task in a radial maze and a two trial object recognition task. After completion of training in the DNMTS task, animals were subjected for 9 weeks to daily injections of either saline or sulbutiamine (12.5 or 25 mg/kg). Sulbutiamine did not modify memory in the DNMTS task but improved it in the object recognition task. Dizocilpine, impaired both acquisition and retention of the DNMTS task in the saline-treated group, but not in the two sulbutiamine-treated groups, suggesting that sulbutiamine may counteract the amnesia induced by a blockade of the N-methyl-D-aspartate glutamate receptors. Taken together, these results are in favor of a beneficial effect of sulbutiamine on working and episodic memory.

Deconstructing the effect of self-directed study on episodic memory

PubMed Central

Markant, Douglas; DuBrow, Sarah; Davachi, Lila; Gureckis, Todd M.

2014-01-01

Self-directed learning is often associated with better long-term memory retention, however, the mechanisms that underlie this advantage remain poorly understood. This series of experiments was designed to “deconstruct” the notion of self-directed learning in order to better identify the factors most responsible for these improvements to memory. In particular, we isolate the memory advantage that comes from controlling the content of study episodes from the advantage that comes from controlling the timing of those episodes. Across four experiments, self-directed learning significantly enhanced recognition memory relative to passive observation. However, the advantage for self-directed learning was found to be present even under extremely minimal conditions of volitional control (simply pressing a button when ready to advance to the next item). Our results suggest that improvements to memory following self-directed encoding may be related to the ability to coordinate stimulus presentation with the learner’s current preparatory or attentional state, and highlight the need to consider the range of cognitive control processes involved in and influenced by self-directed study. PMID:24941938

Effects of Repetition Priming on Recognition Memory: Testing a Perceptual Fluency-Disfluency Model

ERIC Educational Resources Information Center

Huber, David E.; Clark, Tedra F.; Curran, Tim; Winkielman, Piotr

2008-01-01

Five experiments explored the effects of immediate repetition priming on episodic recognition (the "Jacoby-Whitehouse effect") as measured with forced-choice testing. These experiments confirmed key predictions of a model adapted from D. E. Huber and R. C. O'Reilly's (2003) dynamic neural network of perception. In this model, short prime durations…

Remembering versus Knowing during Face Recognition in Unilateral Temporal Lobe Epilepsy Patients with or without Hippocampal Sclerosis

ERIC Educational Resources Information Center

Bengner, Thomas; Malina, Thomas

2008-01-01

Recognition memory involves knowing an item was learned (familiarity) and remembering contextual details about the prior learning episode (recollection). We tested three competing hypotheses about the role of the hippocampus in recollection and familiarity. It mediates either recollection or familiarity, or serves both processes. We further tested…

Predicting episodic memory formation for movie events

PubMed Central

Tang, Hanlin; Singer, Jed; Ison, Matias J.; Pivazyan, Gnel; Romaine, Melissa; Frias, Rosa; Meller, Elizabeth; Boulin, Adrianna; Carroll, James; Perron, Victoria; Dowcett, Sarah; Arellano, Marlise; Kreiman, Gabriel

2016-01-01

Episodic memories are long lasting and full of detail, yet imperfect and malleable. We quantitatively evaluated recollection of short audiovisual segments from movies as a proxy to real-life memory formation in 161 subjects at 15 minutes up to a year after encoding. Memories were reproducible within and across individuals, showed the typical decay with time elapsed between encoding and testing, were fallible yet accurate, and were insensitive to low-level stimulus manipulations but sensitive to high-level stimulus properties. Remarkably, memorability was also high for single movie frames, even one year post-encoding. To evaluate what determines the efficacy of long-term memory formation, we developed an extensive set of content annotations that included actions, emotional valence, visual cues and auditory cues. These annotations enabled us to document the content properties that showed a stronger correlation with recognition memory and to build a machine-learning computational model that accounted for episodic memory formation in single events for group averages and individual subjects with an accuracy of up to 80%. These results provide initial steps towards the development of a quantitative computational theory capable of explaining the subjective filtering steps that lead to how humans learn and consolidate memories. PMID:27686330

Predicting episodic memory formation for movie events.

PubMed

Tang, Hanlin; Singer, Jed; Ison, Matias J; Pivazyan, Gnel; Romaine, Melissa; Frias, Rosa; Meller, Elizabeth; Boulin, Adrianna; Carroll, James; Perron, Victoria; Dowcett, Sarah; Arellano, Marlise; Kreiman, Gabriel

2016-09-30

Episodic memories are long lasting and full of detail, yet imperfect and malleable. We quantitatively evaluated recollection of short audiovisual segments from movies as a proxy to real-life memory formation in 161 subjects at 15 minutes up to a year after encoding. Memories were reproducible within and across individuals, showed the typical decay with time elapsed between encoding and testing, were fallible yet accurate, and were insensitive to low-level stimulus manipulations but sensitive to high-level stimulus properties. Remarkably, memorability was also high for single movie frames, even one year post-encoding. To evaluate what determines the efficacy of long-term memory formation, we developed an extensive set of content annotations that included actions, emotional valence, visual cues and auditory cues. These annotations enabled us to document the content properties that showed a stronger correlation with recognition memory and to build a machine-learning computational model that accounted for episodic memory formation in single events for group averages and individual subjects with an accuracy of up to 80%. These results provide initial steps towards the development of a quantitative computational theory capable of explaining the subjective filtering steps that lead to how humans learn and consolidate memories.

Proactive interference and concurrent inhibitory processes do not differentially affect item and associative recognition: Implication for the age-related associative memory deficit.

PubMed

Guez, Jonathan; Naveh-Benjamin, Moshe

2016-09-01

Previous studies have suggested an associative deficit hypothesis [Naveh-Benjamin, M. ( 2000 ). Adult age differences in memory performance: Tests of an associative deficit hypothesis. Journal of Experimental Psychology: Learning, Memory, and Cognition, 26, 1170-1187] to explain age-related episodic memory declines. The hypothesis attributes part of the deficient episodic memory performance in older adults to a difficulty in creating and retrieving cohesive episodes. In this article, we further evaluate this hypothesis by testing two alternative processes that potentially mediate associative memory deficits in older adults. Four experiments are presented that assess whether failure of inhibitory processes (proactive interference in Experiments 1 and 2), and concurrent inhibition (in Experiments 3 and 4) are mediating factors in age-related associative deficits. The results suggest that creating conditions that require the operation of inhibitory processes, or that interfere with such processes, cannot simulate associative memory deficit in older adults. Instead, such results support the idea that associative memory deficits reflect a unique binding failure in older adults. This failure seems to be independent of other cognitive processes, including inhibitory and other resource-demanding processes.

Functional-anatomic study of episodic retrieval using fMRI. I. Retrieval effort versus retrieval success.

PubMed

Buckner, R L; Koutstaal, W; Schacter, D L; Wagner, A D; Rosen, B R

1998-04-01

A number of recent functional imaging studies have identified brain areas activated during tasks involving episodic memory retrieval. The identification of such areas provides a foundation for targeted hypotheses regarding the more specific contributions that these areas make to episodic retrieval. As a beginning effort toward such an endeavor, whole-brain functional magnetic resonance imaging (fMRI) was used to examine 14 subjects during episodic word recognition in a block-designed fMRI experiment. Study conditions were manipulated by presenting either shallow or deep encoding tasks. This manipulation yielded two recognition conditions that differed with regard to retrieval effort and retrieval success: shallow encoding yielded low levels of recognition success with high levels of retrieval effort, and deep encoding yielded high levels of recognition success with low levels of effort. Many brain areas were activated in common by these two recognition conditions compared to a low-level fixation condition, including left and right prefrontal regions often detected during PET episodic retrieval paradigms (e.g., R. L. Buckner et al., 1996, J. Neurosci. 16, 6219-6235) thereby generalizing these findings to fMRI. Characterization of the activated regions in relation to the separate recognition conditions showed (1) bilateral anterior insular regions and a left dorsal prefrontal region were more active after shallow encoding, when retrieval demanded greatest effort, and (2) right anterior prefrontal cortex, which has been implicated in episodic retrieval, was most active during successful retrieval after deep encoding. We discuss these findings in relation to component processes involved in episodic retrieval and in the context of a companion study using event-related fMRI.

Remember and Know Judgments During Recognition in Chronic Schizophrenia

PubMed Central

van Erp, Theo G.M.; Lesh, Tyler A.; Knowlton, Barbara J.; Bearden, Carrie E.; Hardt, Molly; Karlsgodt, Katherine H.; Shirinyan, David; Rao, Vikas; Green, Michael F.; Subotnik, Kenneth L.; Nuechterlein, Keith; Cannon, Tyrone D.

2008-01-01

Deficits in learning and memory are among the most robust correlates of schizophrenia. It has been hypothesized that these deficits are in part due to reduced conscious recollection and increased reliance on familiarity assessment as a basis for retrieval. The Remember-Know (R-K) paradigm was administered to 35 patients with chronic schizophrenia and 35 healthy controls. In addition to making “remember” and “know” judgments, the participants were asked to make forced choice recognition judgments with regard to details about the learning episode. Analyses comparing response types showed a significant reduction in “remember” responses and a significant increase in “know” responses in schizophrenia patients relative to controls. Both patients and controls recalled more details of the learning episode for “remember” compared to “know” responses, although, in particular for “remember” responses, patients recalled fewer details compared with controls. Notably, patients recognized fewer inter-item but not intra-item stimulus features compared with controls. These findings suggest deficits in organizing and integrating relational information during the learning episode and/or using relational information for retrieval. A Dual-Process Signal Detection interpretation of these findings suggests that recollection in chronic schizophrenia is significantly reduced, while familiarity is not. Additionally, a unidimensional Signal Detection Theory interpretation suggests that chronic schizophrenia patients show a reduction in memory strength, and an altered criterion on the memory strength distribution for detecting new compared with old stimuli but not for detecting stimuli that are remembered versus familiar. Taken together, these findings are consistent with a deficit in recollection and increased reliance on familiarity in making recognition memory judgments in chronic schizophrenia. PMID:17964760

Electrophysiological evidence for flexible goal-directed cue processing during episodic retrieval.

PubMed

Herron, Jane E; Evans, Lisa H; Wilding, Edward L

2016-05-15

A widely held assumption is that memory retrieval is aided by cognitive control processes that are engaged flexibly in service of memory retrieval and memory decisions. While there is some empirical support for this view, a notable exception is the absence of evidence for the flexible use of retrieval control in functional neuroimaging experiments requiring frequent switches between tasks with different cognitive demands. This absence is troublesome in so far as frequent switches between tasks mimic some of the challenges that are typically placed on memory outside the laboratory. In this experiment we instructed participants to alternate frequently between three episodic memory tasks requiring item recognition or retrieval of one of two different kinds of contextual information encoded in a prior study phase (screen location or encoding task). Event-related potentials (ERPs) elicited by unstudied items in the two tasks requiring retrieval of study context were reliably different, demonstrating for the first time that ERPs index task-specific processing of retrieval cues when retrieval goals change frequently. The inclusion of the item recognition task was a novel and important addition in this study, because only the ERPs elicited by unstudied items in one of the two context conditions diverged from those in the item recognition condition. This outcome constrains functional interpretations of the differences that emerged between the two context conditions and emphasises the utility of this baseline in functional imaging studies of retrieval processing operations. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Electrophysiological evidence for flexible goal-directed cue processing during episodic retrieval

PubMed Central

Herron, Jane E.; Evans, Lisa H.; Wilding, Edward L.

2016-01-01

A widely held assumption is that memory retrieval is aided by cognitive control processes that are engaged flexibly in service of memory retrieval and memory decisions. While there is some empirical support for this view, a notable exception is the absence of evidence for the flexible use of retrieval control in functional neuroimaging experiments requiring frequent switches between tasks with different cognitive demands. This absence is troublesome in so far as frequent switches between tasks mimic some of the challenges that are typically placed on memory outside the laboratory. In this experiment we instructed participants to alternate frequently between three episodic memory tasks requiring item recognition or retrieval of one of two different kinds of contextual information encoded in a prior study phase (screen location or encoding task). Event-related potentials (ERPs) elicited by unstudied items in the two tasks requiring retrieval of study context were reliably different, demonstrating for the first time that ERPs index task-specific processing of retrieval cues when retrieval goals change frequently. The inclusion of the item recognition task was a novel and important addition in this study, because only the ERPs elicited by unstudied items in one of the two context conditions diverged from those in the item recognition condition. This outcome constrains functional interpretations of the differences that emerged between the two context conditions and emphasises the utility of this baseline in functional imaging studies of retrieval processing operations. PMID:26892854

Repetition priming across distinct contexts: effects of lexical status, word frequency, and retrieval test.

PubMed

Coane, Jennifer H; Balota, David A

2010-12-01

Repetition priming, the facilitation observed when a target is preceded by an identity prime, is a robust phenomenon that occurs across a variety of conditions. Oliphant (1983), however, failed to observe repetition priming for targets embedded in the instructions to an experiment in a subsequent lexical decision task. In the present experiments, we examined the roles of priming context (list or instructions), target lexicality, and target frequency in both lexical decision and episodic recognition performance. Initial encoding context did not modulate priming in lexical decision or recognition memory for low-frequency targets or nonwords, whereas context strongly modulated episodic recognition for high-frequency targets. The results indicate that priming across contexts is sensitive to the distinctiveness of the trace and the reliance on episodic retrieval mechanisms. These results also shed light on the influence of event boundaries, such that priming occurs across different events for relatively distinct (low-frequency) items.

Familiarity and recollection processes in patients with recent-onset schizophrenia and their unaffected parents.

PubMed

Lefèbvre, Andrée-Anne; Cellard, Caroline; Tremblay, Sébastien; Achim, Amélie; Rouleau, Nancie; Maziade, Michel; Roy, Marc-André

2010-01-30

Episodic memory deficits are present in patients with schizophrenia (SZ) and their unaffected relatives and could be considered as a cognitive indicator of genetic vulnerability to SZ. The present study, involving patients with SZ as well as their parents, used experimental tasks specifically designed to disentangle the contribution of familiarity and recollection processes to episodic memory. The performance of patients with SZ (n=26) and their unaffected parents (n=35) was compared with that of healthy control groups matched on socio-demographic variables (controls of patients, n=26; controls of parents, n=35) on two memory tasks assessing recollection and familiarity. The first task was designed to investigate item recognition and memory for item-spatial context associations whereas the second targeted item-item associations. The results revealed an overall episodic memory deficit in patients with SZ, encompassing both familiarity and recollection, while unaffected parents showed a dysfunction restricted to the recollection process. Our study highlights differences and similarities in the source of the episodic memory deficit found in patients with SZ and their unaffected parents, and it suggests that recollection could act as a cognitive endophenotype of SZ. The results also suggest that use of experimental tasks represents a promising method in the search of cognitive endophenotypes in SZ.

Depth rotation and mirror-image reflection reduce affective preference as well as recognition memory for pictures of novel objects.

PubMed

Lawson, Rebecca

2004-10-01

In two experiments, the identification of novel 3-D objects was worse for depth-rotated and mirror-reflected views, compared with the study view in an implicit affective preference memory task, as well as in an explicit recognition memory task. In Experiment 1, recognition was worse and preference was lower when depth-rotated views of an object were paired with an unstudied object relative to trials when the study view of that object was shown. There was a similar trend for mirror-reflected views. In Experiment 2, the study view of an object was both recognized and preferred above chance when it was paired with either depth-rotated or mirror-reflected views of that object. These results suggest that view-sensitive representations of objects mediate performance in implicit, as well as explicit, memory tasks. The findings do not support the claim that separate episodic and structural description representations underlie performance in implicit and explicit memory tasks, respectively.

Theta-burst microstimulation in the human entorhinal area improves memory specificity.

PubMed

Titiz, Ali S; Hill, Michael R H; Mankin, Emily A; M Aghajan, Zahra; Eliashiv, Dawn; Tchemodanov, Natalia; Maoz, Uri; Stern, John; Tran, Michelle E; Schuette, Peter; Behnke, Eric; Suthana, Nanthia A; Fried, Itzhak

2017-10-24

The hippocampus is critical for episodic memory, and synaptic changes induced by long-term potentiation (LTP) are thought to underlie memory formation. In rodents, hippocampal LTP may be induced through electrical stimulation of the perforant path. To test whether similar techniques could improve episodic memory in humans, we implemented a microstimulation technique that allowed delivery of low-current electrical stimulation via 100 μm -diameter microelectrodes. As thirteen neurosurgical patients performed a person recognition task, microstimulation was applied in a theta-burst pattern, shown to optimally induce LTP. Microstimulation in the right entorhinal area during learning significantly improved subsequent memory specificity for novel portraits; participants were able both to recognize previously-viewed photos and reject similar lures. These results suggest that microstimulation with physiologic level currents-a radical departure from commonly used deep brain stimulation protocols-is sufficient to modulate human behavior and provides an avenue for refined interrogation of the circuits involved in human memory.

Active retrieval facilitates across-episode binding by modulating the content of memory

PubMed Central

Bridge, Donna J.; Voss, Joel L.

2014-01-01

The contents of memory can be updated when information from the current episode is bound with content retrieved from previous episodes. Little is known regarding factors that determine the memory content that is subject to this across-episode binding. We tested whether across-episode binding preferentially occurs for memory content that is currently “active” and identified relevant neural correlates. After studying objects at specific locations on scene backgrounds, subjects performed one of two retrieval tasks for the objects on different scene backgrounds. In an active condition, subjects recalled object locations, whereas subjects merely dragged objects to predetermined locations in a passive condition. Immediately following each object-location retrieval event, a novel face appeared on a blank screen. We hypothesized that the original episode content would be active in memory during face encoding in the active condition, but not in the passive condition (despite seeing the same content in both conditions). A ramification of the active condition would thus be preferential binding of original episode content to novel faces, with no such across-episode binding in the passive condition. Indeed, memory for faces was better when tested on the original background scenes in the active relative to passive condition, indicating that original episode content was bound with the active condition faces, whereas this occurred to a lesser extent for the passive condition faces. Likewise, early-onset negative ERP effects reflected binding of the face to the original episode content in the active but not the passive condition. In contrast, binding in the passive condition occurred only when faces were physically displayed on the original scenes during recognition testing, and a very similar early-onset negative ERP effect signaled binding in this condition. ERP correlates of binding were thus similar for across-episode and within-episode binding (and were distinct from other encoding and retrieval ERP signals in both cases), indicating that active retrieval modulated when binding occurred, not the nature of the binding process per se. These results suggest that active retrieval promotes binding of new information with contents of memory, whereas without active retrieval, these unrelated pieces of information might be bound only when they are physically paired. PMID:25173711

The posterior parietal cortex in recognition memory: a neuropsychological study.

PubMed

Haramati, Sharon; Soroker, Nachum; Dudai, Yadin; Levy, Daniel A

2008-01-01

Several recent functional neuroimaging studies have reported robust bilateral activation (L>R) in lateral posterior parietal cortex and precuneus during recognition memory retrieval tasks. It has not yet been determined what cognitive processes are represented by those activations. In order to examine whether parietal lobe-based processes are necessary for basic episodic recognition abilities, we tested a group of 17 first-incident CVA patients whose cortical damage included (but was not limited to) extensive unilateral posterior parietal lesions. These patients performed a series of tasks that yielded parietal activations in previous fMRI studies: yes/no recognition judgments on visual words and on colored object pictures and identifiable environmental sounds. We found that patients with left hemisphere lesions were not impaired compared to controls in any of the tasks. Patients with right hemisphere lesions were not significantly impaired in memory for visual words, but were impaired in recognition of object pictures and sounds. Two lesion--behavior analyses--area-based correlations and voxel-based lesion symptom mapping (VLSM)---indicate that these impairments resulted from extra-parietal damage, specifically to frontal and lateral temporal areas. These findings suggest that extensive parietal damage does not impair recognition performance. We suggest that parietal activations recorded during recognition memory tasks might reflect peri-retrieval processes, such as the storage of retrieved memoranda in a working memory buffer for further cognitive processing.

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

PubMed Central

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

2017-01-01

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 (Mage = 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. PMID:28119597

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

PubMed

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.

Sources of interference in item and associative recognition memory.

PubMed

Osth, Adam F; Dennis, Simon

2015-04-01

A powerful theoretical framework for exploring recognition memory is the global matching framework, in which a cue's memory strength reflects the similarity of the retrieval cues being matched against the contents of memory simultaneously. Contributions at retrieval can be categorized as matches and mismatches to the item and context cues, including the self match (match on item and context), item noise (match on context, mismatch on item), context noise (match on item, mismatch on context), and background noise (mismatch on item and context). We present a model that directly parameterizes the matches and mismatches to the item and context cues, which enables estimation of the magnitude of each interference contribution (item noise, context noise, and background noise). The model was fit within a hierarchical Bayesian framework to 10 recognition memory datasets that use manipulations of strength, list length, list strength, word frequency, study-test delay, and stimulus class in item and associative recognition. Estimates of the model parameters revealed at most a small contribution of item noise that varies by stimulus class, with virtually no item noise for single words and scenes. Despite the unpopularity of background noise in recognition memory models, background noise estimates dominated at retrieval across nearly all stimulus classes with the exception of high frequency words, which exhibited equivalent levels of context noise and background noise. These parameter estimates suggest that the majority of interference in recognition memory stems from experiences acquired before the learning episode. (c) 2015 APA, all rights reserved).

Interactions between Visual Attention and Episodic Retrieval: Dissociable Contributions of Parietal Regions during Gist-Based False Recognition

PubMed Central

Guerin, Scott A.; Robbins, Clifford A.; Gilmore, Adrian W.; Schacter, Daniel L.

2012-01-01

SUMMARY The interaction between episodic retrieval and visual attention is relatively unexplored. Given that systems mediating attention and episodic memory appear to be segregated, and perhaps even in competition, it is unclear how visual attention is recruited during episodic retrieval. We investigated the recruitment of visual attention during the suppression of gist-based false recognition, the tendency to falsely recognize items that are similar to previously encountered items. Recruitment of visual attention was associated with activity in the dorsal attention network. The inferior parietal lobule, often implicated in episodic retrieval, tracked veridical retrieval of perceptual detail and showed reduced activity during the engagement of visual attention, consistent with a competitive relationship with the dorsal attention network. These findings suggest that the contribution of the parietal cortex to interactions between visual attention and episodic retrieval entails distinct systems that contribute to different components of the task while also suppressing each other. PMID:22998879

The effects of meaningful irrelevant speech and road traffic noise on teachers' attention, episodic and semantic memory.

PubMed

Enmarker, Ingela

2004-11-01

The aim of the present experiment was to examine the effects of meaningful irrelevant speech and road traffic noise on attention, episodic and semantic memory, and also to examine whether the noise effects were age-dependent. A total of 96 male and female teachers in the age range of 35-45 and 55-65 years were randomly assigned to a silent or the two noise conditions. Noise effects found in episodic memory were limited to a meaningful text, where cued recall contrary to expectations was equally impaired by the two types of noise. However, meaningful irrelevant speech also deteriorated recognition of the text, whereas road traffic noise caused no decrement. Retrieval from two word fluency tests in semantic memory showed strong effects of noise exposure, one affected by meaningful irrelevant speech and the other by road traffic noise. The results implied that both acoustic variation and the semantic interference could be of importance for noise impairments. The expected age-dependent noise effects did not show up.

Seeing Colors: Cultural and Environmental Influences on Episodic Memory.

PubMed

Persaud, Kimele; Hemmer, Pernille; Kidd, Celeste; Piantadosi, Steven

2017-01-01

Expectations learned from our perceptual experiences, culture, and language can shape how we perceive, interact with, and remember features of the past. Here, we questioned whether environment also plays a role. We tested recognition memory for color in Bolivia's indigenous Tsimanè people, who experience a different color environment than standard U.S. We found that memory regressed differently between the groups, lending credence to the idea that environmental variations engender differences in expectations, and in turn perceptual memory for color.

Effects on locomotion and memory in 2 models of cerebral hypoperfusion in male Wistar rats.

PubMed

Martínez-Díaz, J A; García, L I; Hernández, M E; Aranda-Abreu, G E

2015-09-01

Cerebral ischaemia is one of the most common neurological diseases worldwide. Its many sequelae range from motor and sensory symptoms to cognitive decline and dementia. Animal models of cerebral ischaemia/hypoperfusion elicit effects on long term memory; however, the effects of these procedures on short term memory are not clearly understood and effects induced by alternative hypoperfusion models are completely unknown. We evaluated the effects of 2 cerebral hyperperfusion models on memory in 3-month-old male rats. Episodic memory and working memory were assessed using the new object recognition test and the spontaneous alteration test, respectively. Neurological assessment was also performed, along with an open field test to evaluate locomotor activity. Rats in both hyperperfusion models displayed no cognitive changes. Rats with unilateral left-sided ligation plus temporary ligation of the right carotid tended to show slightly impaired performance on the new object recognition test on the second day after the procedure. In contrast, the group with permanent unilateral ligation tended to display alterations in working and episodic memory 9 days after the procedure, but they subsequently recovered. Despite these differences, both hypoperfusion groups displayed clear signs of motor impairment 2 days after the procedure, as reflected by their decreased locomotor activity during the open field test. Copyright © 2014 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

Global Similarity Predicts Dissociation of Classification and Recognition: Evidence Questioning the Implicit-Explicit Learning Distinction in Amnesia

ERIC Educational Resources Information Center

Jamieson, Randall K.; Holmes, Signy; Mewhort, D. J. K.

2010-01-01

Dissociation of classification and recognition in amnesia is widely taken to imply 2 functional systems: an implicit procedural-learning system that is spared in amnesia and an explicit episodic-learning system that is compromised. We argue that both tasks reflect the global similarity of probes to memory. In classification, subjects sort…

Source Memory in Korsakoff Syndrome: Disentangling the Mechanisms of Temporal Confusion.

PubMed

Brion, Mélanie; de Timary, Philippe; Pitel, Anne-Lise; Maurage, Pierre

2017-03-01

Korsakoff syndrome (KS), most frequently resulting from alcohol dependence (ALC), is characterized by severe anterograde amnesia. It has been suggested that these deficits may extend to other memory components, and notably source memory deficits involved in the disorientation and temporal confusion frequently observed in KS. However, the extent of this source memory impairment in KS and its usefulness for the differential diagnosis between ALC and KS remain unexplored. Nineteen patients with KS were compared with 19 alcohol-dependent individuals and 19 controls in a source memory test exploring temporal context confusions ("continuous recognition task"). Episodic memory and psychopathological comorbidities were controlled for. While no source memory deficit was observed in ALC, KS was associated with a significant presence of temporal context confusion, even when the influence of comorbidities was taken into account. This source memory impairment did not appear to be related to performances on episodic memory or executive functions. Patients with KS displayed source memory deficits, as indexed by temporal context confusions. The absence of a relationship with episodic memory performances seems to indicate that source memory impairment is not a mere by-product of amnesia. As ALC was associated with preserved source memory, the presence of temporal context confusion may serve as a complementary tool for the differential diagnosis between ALC and KS. Copyright © 2017 by the Research Society on Alcoholism.

Levels-of-processing effect on frontotemporal function in schizophrenia during word encoding and recognition.

PubMed

Ragland, J Daniel; Gur, Ruben C; Valdez, Jeffrey N; Loughead, James; Elliott, Mark; Kohler, Christian; Kanes, Stephen; Siegel, Steven J; Moelter, Stephen T; Gur, Raquel E

2005-10-01

Patients with schizophrenia improve episodic memory accuracy when given organizational strategies through levels-of-processing paradigms. This study tested if improvement is accompanied by normalized frontotemporal function. Event-related blood-oxygen-level-dependent functional magnetic resonance imaging (fMRI) was used to measure activation during shallow (perceptual) and deep (semantic) word encoding and recognition in 14 patients with schizophrenia and 14 healthy comparison subjects. Despite slower and less accurate overall word classification, the patients showed normal levels-of-processing effects, with faster and more accurate recognition of deeply processed words. These effects were accompanied by left ventrolateral prefrontal activation during encoding in both groups, although the thalamus, hippocampus, and lingual gyrus were overactivated in the patients. During word recognition, the patients showed overactivation in the left frontal pole and had a less robust right prefrontal response. Evidence of normal levels-of-processing effects and left prefrontal activation suggests that patients with schizophrenia can form and maintain semantic representations when they are provided with organizational cues and can improve their word encoding and retrieval. Areas of overactivation suggest residual inefficiencies. Nevertheless, the effect of teaching organizational strategies on episodic memory and brain function is a worthwhile topic for future interventional studies.

Semantic memory influences episodic retrieval by increased familiarity.

PubMed

Wang, Yujuan; Mao, Xinrui; Li, Bingcan; Lu, Baoqing; Guo, Chunyan

2016-07-06

The role of familiarity in associative recognition has been investigated in a number of studies, which have indicated that familiarity can facilitate recognition under certain circumstances. The ability of a pre-experimentally existing common representation to boost the contribution of familiarity has rarely been investigated. In addition, although many studies have investigated the interactions between semantic memory and episodic retrieval, the conditions that influence the presence of specific patterns were unclear. This study aimed to address these two questions. We manipulated the degree of overlap between the two representations using synonym and nonsynonym pairs in an associative recognition task. Results indicated that an increased degree of overlap enhanced recognition performance. The analysis of event-related potentials effects in the test phase showed that synonym pairs elicited both types of old/rearranged effects, whereas nonsynonym pairs elicited a late old/rearranged effect. These results confirmed that a common representation, irrespective of source, was necessary for assuring the presence of familiarity, but a common representation could not distinguish associative recognition depending on familiarity alone. Moreover, our expected double dissociation between familiarity and recollection was absent, which indicated that mode selection may be influenced by the degree of distinctness between old and rearranged pairs rather than the degree of overlap between representations.

From Perception to Metacognition: Auditory and Olfactory Functions in Early Blind, Late Blind, and Sighted Individuals

PubMed Central

Cornell Kärnekull, Stina; Arshamian, Artin; Nilsson, Mats E.; Larsson, Maria

2016-01-01

Although evidence is mixed, studies have shown that blind individuals perform better than sighted at specific auditory, tactile, and chemosensory tasks. However, few studies have assessed blind and sighted individuals across different sensory modalities in the same study. We tested early blind (n = 15), late blind (n = 15), and sighted (n = 30) participants with analogous olfactory and auditory tests in absolute threshold, discrimination, identification, episodic recognition, and metacognitive ability. Although the multivariate analysis of variance (MANOVA) showed no overall effect of blindness and no interaction with modality, follow-up between-group contrasts indicated a blind-over-sighted advantage in auditory episodic recognition, that was most pronounced in early blind individuals. In contrast to the auditory modality, there was no empirical support for compensatory effects in any of the olfactory tasks. There was no conclusive evidence for group differences in metacognitive ability to predict episodic recognition performance. Taken together, the results showed no evidence of an overall superior performance in blind relative sighted individuals across olfactory and auditory functions, although early blind individuals exceled in episodic auditory recognition memory. This observation may be related to an experience-induced increase in auditory attentional capacity. PMID:27729884

Dissociating neural markers of stimulus memorability and subjective recognition during episodic retrieval.

PubMed

Bainbridge, Wilma A; Rissman, Jesse

2018-06-06

While much of memory research takes an observer-centric focus looking at participant performance, recent work has pinpointed important item-centric effects on memory, or how intrinsically memorable a given stimulus is. However, little is known about the neural correlates of memorability during memory retrieval, or how such correlates relate to subjective memory behavior. Here, stimuli and blood-oxygen-level dependent data from a prior functional magnetic resonance imaging (fMRI) study were reanalyzed using a memorability-based framework. In that study, sixteen participants studied 200 novel face images and were scanned while making recognition memory judgments on those faces, interspersed with 200 unstudied faces. In the current investigation, memorability scores for those stimuli were obtained through an online crowd-sourced (N = 740) continuous recognition test that measured each image's corrected recognition rate. Representational similarity analyses were conducted across the brain to identify regions wherein neural pattern similarity tracked item-specific effects (stimulus memorability) versus observer-specific effects (individual memory performance). We find two non-overlapping sets of regions, with memorability-related information predominantly represented within ventral and medial temporal regions and memory retrieval outcome-related information within fronto-parietal regions. These memorability-based effects persist regardless of image history, implying that coding of stimulus memorability may be a continuous and automatic perceptual process.

Unforgettable film music: The role of emotion in episodic long-term memory for music

PubMed Central

Eschrich, Susann; Münte, Thomas F; Altenmüller, Eckart O

2008-01-01

Background Specific pieces of music can elicit strong emotions in listeners and, possibly in connection with these emotions, can be remembered even years later. However, episodic memory for emotional music compared with less emotional music has not yet been examined. We investigated whether emotional music is remembered better than less emotional music. Also, we examined the influence of musical structure on memory performance. Results Recognition of 40 musical excerpts was investigated as a function of arousal, valence, and emotional intensity ratings of the music. In the first session the participants judged valence and arousal of the musical pieces. One week later, participants listened to the 40 old and 40 new musical excerpts randomly interspersed and were asked to make an old/new decision as well as to indicate arousal and valence of the pieces. Musical pieces that were rated as very positive were recognized significantly better. Conclusion Musical excerpts rated as very positive are remembered better. Valence seems to be an important modulator of episodic long-term memory for music. Evidently, strong emotions related to the musical experience facilitate memory formation and retrieval. PMID:18505596

Unforgettable film music: the role of emotion in episodic long-term memory for music.

PubMed

Eschrich, Susann; Münte, Thomas F; Altenmüller, Eckart O

2008-05-28

Specific pieces of music can elicit strong emotions in listeners and, possibly in connection with these emotions, can be remembered even years later. However, episodic memory for emotional music compared with less emotional music has not yet been examined. We investigated whether emotional music is remembered better than less emotional music. Also, we examined the influence of musical structure on memory performance. Recognition of 40 musical excerpts was investigated as a function of arousal, valence, and emotional intensity ratings of the music. In the first session the participants judged valence and arousal of the musical pieces. One week later, participants listened to the 40 old and 40 new musical excerpts randomly interspersed and were asked to make an old/new decision as well as to indicate arousal and valence of the pieces. Musical pieces that were rated as very positive were recognized significantly better. Musical excerpts rated as very positive are remembered better. Valence seems to be an important modulator of episodic long-term memory for music. Evidently, strong emotions related to the musical experience facilitate memory formation and retrieval.

Some-or-none recollection: Evidence from item and source memory.

PubMed

Onyper, Serge V; Zhang, Yaofei X; Howard, Marc W

2010-05-01

Dual-process theory hypothesizes that recognition memory depends on 2 distinguishable memory signals. Recollection reflects conscious recovery of detailed information about the learning episode. Familiarity reflects a memory signal that is not accompanied by a vivid conscious experience but nonetheless enables participants to distinguish recently experienced probe items from novel ones. This dual-process explanation of recognition memory has gained wide acceptance among cognitive neuroscientists and some cognitive psychologists. Nonetheless, its difficulty in providing a quantitatively satisfactory description of performance has precluded a consensus not only regarding the theoretical structure of recognition memory but also about how to best measure recognition accuracy. In 2 experiments we show that neither the standard formulation of dual-process signal detection (DPSD) theory nor a widely used single-process model called the unequal-variance signal-detection (UVSD) model provides a satisfactory explanation of recognition memory across different types of stimuli (words and travel scenes). In the variable-recollection dual-process (VRDP) model, recollection fails for some old probe items, as in standard formulations of DPSD, but gives rise to a continuous distribution of memory strengths when it succeeds. The VRDP can approximate both the DPSD and UVSD. In both experiments it provides a consistently superior fit across materials to the superset of the DPSD and UVSD. The VRDP offers a simple explanation of the form of conjoint item-source judgments, something neither the DPSD nor UVSD accomplishes. The success of the VRDP supports the core assumptions of dual-process theory by providing an excellent quantitative description of recognition performance across materials and response criteria.

Declarative memory.

PubMed

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.

Strengthening of Existing Episodic Memories Through Non-invasive Stimulation of Prefrontal Cortex in Older Adults with Subjective Memory Complaints

PubMed Central

Manenti, Rosa; Sandrini, Marco; Gobbi, Elena; Cobelli, Chiara; Brambilla, Michela; Binetti, Giuliano; Cotelli, Maria

2017-01-01

Episodic memory is critical to daily life functioning. This type of declarative memory declines with age and is the earliest cognitive function to be compromised in Alzheimer’s disease (AD). Subjective memory complaints are commonly reported by older adults and have been considered a risk factor for developing AD. The possibilities for prevention of memory disorders in older adults have increased substantially in recent years. Previous studies have shown that anodal transcranial Direct Current Stimulation (tDCS) applied over the left lateral prefrontal cortex (PFC) after a contextual reminder strengthened existing verbal episodic memories, conceivably through reconsolidation, in elderly people. In this study, we hypothesized that anodal tDCS applied over the left lateral PFC after a contextual reminder would improve delayed memory retrieval relative to placebo (sham) stimulation in elderly individuals with SMC. Twenty-two subjects learned a list of words. Twenty-four hour later, tDCS (anodal or placebo) was applied over the left lateral PFC after a contextual reminder. Memory retrieval was tested 48h and 30 days later. These findings showed that anodal tDCS over the left lateral PFC strengthened existing episodic memories, a behavioral effect documented by improved recognition up to 30 days, relative to placebo stimulation. This study suggests that tDCS after a contextual reminder can induce long-lasting beneficial effects by facilitating the consolidation processes and opens up the possibility to design specific non-invasive interventions aimed at preventing memory decline in this at-risk population. PMID:29259554

Is lorazepam-induced amnesia specific to the type of memory or to the task used to assess it?

PubMed

File, S E; Sharma, R; Shaffer, J

1992-01-01

Retrieval tasks can be classified along a continuum from conceptually driven (relying on the encoded meaning of the material) to data driven (relying on the perceptual record and surface features of the material). Since most explicit memory tests are conceptually driven and most implicit memory tests are data driven there has been considerable confounding of the memory system being assessed and the processing required by the retrieval task. The purpose of the present experiment was to investigate the effects of lorazepam on explicit memory, using both types of retrieval task. Lorazepam (2.5 mg) or matched placebo was administered to healthy volunteers and changes in subjective mood ratings and in performance in tests of memory were measured. Lorazepam made subjects significantly more drowsy, feeble, clumsy, muzzy, lethargic and mentally slow. Lorazepam significantly impaired recognition memory for slides, impaired the number of words remembered when the retrieval was cued by the first two letters and reduced the number of pictures remembered when retention was cued with picture fragments. Thus episodic memory was impaired whether the task used was conceptually driven (as in slide recognition) or data driven, as in the other two tasks. Analyses of covariance indicated that the memory impairments were independent of increased sedation, as assessed by self-ratings. In contrast to the deficits in episodic memory, there were no lorazepam-induced impairments in tests of semantic memory, whether this was measured in the conceptually driven task of category generation or in the data-driven task of wordstem completion.

Human Episodic Memory Retrieval Is Accompanied by a Neural Contiguity Effect.

PubMed

Folkerts, Sarah; Rutishauser, Ueli; Howard, Marc W

2018-04-25

Cognitive psychologists have long hypothesized that experiences are encoded in a temporal context that changes gradually over time. When an episodic memory is retrieved, the state of context is recovered-a jump back in time. We recorded from single units in the medial temporal lobe of epilepsy patients performing an item recognition task. The population vector changed gradually over minutes during presentation of the list. When a probe from the list was remembered with high confidence, the population vector reinstated the temporal context of the original presentation of that probe during study, a neural contiguity effect that provides a possible mechanism for behavioral contiguity effects. This pattern was only observed for well remembered probes; old probes that were not well remembered showed an anti-contiguity effect. These results constitute the first direct evidence that recovery of an episodic memory in humans is associated with retrieval of a gradually changing state of temporal context, a neural "jump back in time" that parallels the act of remembering. SIGNIFICANCE STATEMENT Episodic memory is the ability to relive a specific experience from one's life. For decades, researchers have hypothesized that, unlike other forms of memory that can be described as simple associations between stimuli, episodic memory depends on the recovery of a neural representation of spatiotemporal context. During study of a sequence of stimuli, the brain state of epilepsy patients changed slowly over at least a minute. When the participant remembered a particular event from the list, this gradually changing state was recovered. This provides direct confirmation of the prediction from computational models of episodic memory. The resolution of this point means that the study of episodic memory can focus on the mechanisms by which this representation of spatiotemporal context is maintained and sometimes recovered. Copyright © 2018 the authors 0270-6474/18/384200-12$15.00/0.

The effects of a subpsychotic dose of ketamine on recognition and source memory for agency: implications for pharmacological modelling of core symptoms of schizophrenia.

PubMed

Honey, Garry D; O'loughlin, Chris; Turner, Danielle C; Pomarol-Clotet, Edith; Corlett, Philip R; Fletcher, Paul C

2006-02-01

Ketamine is increasingly used to model the cognitive deficits and symptoms of schizophrenia. We investigated the extent to which ketamine administration in healthy volunteers reproduces the deficits in episodic recognition memory and agency source monitoring reported in schizophrenia. Intravenous infusions of placebo or 100 ng/ml ketamine were administered to 12 healthy volunteers in a double-blind, placebo-controlled, randomized, within-subjects study. In response to presented words, the subject or experimenter performed a deep or shallow encoding task, providing a 2(drug) x 2(depth of processing) x 2(agency) factorial design. At test, subjects discriminated old/new words, and recalled the sources (task and agent). Data were analyzed using multinomial modelling to identify item recognition, source memory for agency and task, and guessing biases. Under ketamine, item recognition and cued recall of deeply encoded items were impaired, replicating previous findings. In contrast to schizophrenia, there was a reduced tendency to externalize agency source guessing biases under ketamine. While the recognition memory deficit observed with ketamine is consistent with previous work and with schizophrenia, the changes in source memory differ from those reported in schizophrenic patients. This difference may account for the pattern of psychopathology induced by ketamine.

Retrieval of high-fidelity memory arises from distributed cortical networks.

PubMed

Wais, Peter E; Jahanikia, Sahar; Steiner, Daniel; Stark, Craig E L; Gazzaley, Adam

2017-04-01

Medial temporal lobe (MTL) function is well established as necessary for memory of facts and events. It is likely that lateral cortical regions critically guide cognitive control processes to tune in high-fidelity details that are most relevant for memory retrieval. Here, convergent results from functional and structural MRI show that retrieval of detailed episodic memory arises from lateral cortical-MTL networks, including regions of inferior frontal and angular gyrii. Results also suggest that recognition of items based on low-fidelity, generalized information, rather than memory arising from retrieval of relevant episodic details, is not associated with functional connectivity between MTL and lateral cortical regions. Additionally, individual differences in microstructural properties in white matter pathways, associated with distributed MTL-cortical networks, are positively correlated with better performance on a mnemonic discrimination task. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

SenseCam as a rehabilitation tool in a child with anterograde amnesia.

PubMed

Pauly-Takacs, Katalin; Moulin, Chris J A; Estlin, Edward J

2011-10-01

We present the case of a 13-year-old boy, CJ, with profound episodic memory difficulties following the diagnosis of a metastatic intracranial germ cell tumour and subsequent treatment with radiotherapy and chemotherapy. At the core of this study is the first application of SenseCam to a child with severe memory impairment. CJ was taken for a walk while he was wearing SenseCam. This included visiting four different locations. We manipulated the number of locations he could review on SenseCam "films" and then tested recognition memory (forced choice) for both reviewed and non-reviewed locations. We also collected his justifications for the choices he made. Our results indicate that repeated viewings of SenseCam images support the formation of personal semantic memories. Overall our results suggest that the use of SenseCam in memory rehabilitation extends beyond supporting episodic memory and recollection, and supports the feasibility of its use with children who have marked memory difficulties.

Long-term consolidation of declarative memory: insight from temporal lobe epilepsy.

PubMed

Tramoni, Eve; Felician, Olivier; Barbeau, Emmanuel J; Guedj, Eric; Guye, Maxime; Bartolomei, Fabrice; Ceccaldi, Mathieu

2011-03-01

Several experiments carried out with a subset of patients with temporal lobe epilepsy have demonstrated normal memory performance at standard delays of recall (i.e. minutes to hours) but impaired performance over longer delays (i.e. days or weeks), suggesting altered long-term consolidation mechanisms. These mechanisms were specifically investigated in a group of five adult-onset pharmaco-sensitive patients with temporal lobe epilepsy, exhibiting severe episodic memory complaints despite normal performance at standardized memory assessment. In a first experiment, the magnitude of autobiographical memory loss was evaluated using retrograde personal memory tasks based on verbal and visual cues. In both conditions, results showed an unusual U-shaped pattern of personal memory impairment, encompassing most of the patients' life, sparing however, periods of the childhood, early adulthood and past several weeks. This profile was suggestive of a long-term consolidation impairment of personal episodes, adequately consolidated over 'short-term' delays but gradually forgotten thereafter. Therefore, in a subsequent experiment, patients were submitted to a protocol specifically devised to investigate short and long-term consolidation of contextually-bound experiences (episodic memory) and context-free information (semantic knowledge and single-items). In the short term (1 h), performance at both contextually-free and contextually-bound memory tasks was intact. After a 6-week delay, however, contextually-bound memory performance was impaired while contextually-free memory performance remained preserved. This effect was independent of task difficulty and the modality of retrieval (recall and recognition). Neuroimaging studies revealed the presence of mild metabolic changes within medial temporal lobe structures. Taken together, these results show the existence of different consolidation systems within declarative memory. They suggest that mild medial temporal lobe dysfunction can impede the building and stabilization of episodic memories but leaves long-term semantic and single-items mnemonic traces intact.

Markovian Interpretations of Dual Retrieval Processes

PubMed Central

Gomes, C. F. A.; Nakamura, K.; Reyna, V. F.

2013-01-01

A half-century ago, at the dawn of the all-or-none learning era, Estes showed that finite Markov chains supply a tractable, comprehensive framework for discrete-change data of the sort that he envisioned for shifts in conditioning states in stimulus sampling theory. Shortly thereafter, such data rapidly accumulated in many spheres of human learning and animal conditioning, and Estes’ work stimulated vigorous development of Markov models to handle them. A key outcome was that the data of the workhorse paradigms of episodic memory, recognition and recall, proved to be one- and two-stage Markovian, respectively, to close approximations. Subsequently, Markov modeling of recognition and recall all but disappeared from the literature, but it is now reemerging in the wake of dual-process conceptions of episodic memory. In recall, in particular, Markov models are being used to measure two retrieval operations (direct access and reconstruction) and a slave familiarity operation. In the present paper, we develop this family of models and present the requisite machinery for fit evaluation and significance testing. Results are reviewed from selected experiments in which the recall models were used to understand dual memory processes. PMID:24948840

Age-Related Changes in the Control of Episodic Retrieval: An ERP Study of Recognition Memory in Children and Adults

ERIC Educational Resources Information Center

Czernochowski, Daniela; Mecklinger, Axel; Johansson, Mikael

2009-01-01

We examined developmental aspects of the ability to monitor the temporal context of an item's previous occurrence while event-related potentials (ERPs) were recorded. In a continuous recognition task, children between 10 and 12 years and young adults watched a stream of pictures repeated with a lag of 10-15 intervening items and indicated…

Modeling the dynamics of recognition memory testing with an integrated model of retrieval and decision making.

PubMed

Osth, Adam F; Jansson, Anna; Dennis, Simon; Heathcote, Andrew

2018-08-01

A robust finding in recognition memory is that performance declines monotonically across test trials. Despite the prevalence of this decline, there is a lack of consensus on the mechanism responsible. Three hypotheses have been put forward: (1) interference is caused by learning of test items (2) the test items cause a shift in the context representation used to cue memory and (3) participants change their speed-accuracy thresholds through the course of testing. We implemented all three possibilities in a combined model of recognition memory and decision making, which inherits the memory retrieval elements of the Osth and Dennis (2015) model and uses the diffusion decision model (DDM: Ratcliff, 1978) to generate choice and response times. We applied the model to four datasets that represent three challenges, the findings that: (1) the number of test items plays a larger role in determining performance than the number of studied items, (2) performance decreases less for strong items than weak items in pure lists but not in mixed lists, and (3) lexical decision trials interspersed between recognition test trials do not increase the rate at which performance declines. Analysis of the model's parameter estimates suggests that item interference plays a weak role in explaining the effects of recognition testing, while context drift plays a very large role. These results are consistent with prior work showing a weak role for item noise in recognition memory and that retrieval is a strong cause of context change in episodic memory. Copyright © 2018 Elsevier Inc. All rights reserved.

Top-down and bottom-up attention to memory: a hypothesis (AtoM) on the role of the posterior parietal cortex in memory retrieval.

PubMed

Ciaramelli, Elisa; Grady, Cheryl L; Moscovitch, Morris

2008-01-01

Recent neuroimaging studies have implicated the posterior parietal cortex in episodic memory retrieval, but there is uncertainty about its specific role. Research in the attentional domain has shown that superior parietal lobe (SPL) regions along the intraparietal sulcus are implicated in the voluntary orienting of attention to relevant aspects of the environment, whereas inferior parietal lobe (IPL) regions at the temporo-parietal junction mediate the automatic allocation of attention to task-relevant information. Here we propose that the SPL and the IPL play conceptually similar roles in episodic memory retrieval. We hypothesize that the SPL allocates top-down attention to memory retrieval, whereas the IPL mediates the automatic, bottom-up attentional capture by retrieved memory contents. By reviewing the existing fMRI literature, we show that the posterior intraparietal sulcus of SPL is consistently active when the need for top-down assistance to memory retrieval is supposedly maximal, e.g., for memories retrieved with low vs. high confidence, for familiar vs. recollected memories, for recognition of high vs. low frequency words. On the other hand, the supramarginal gyrus of IPL is consistently active when the attentional capture by memory contents is supposedly maximal, i.e., for strong vs. weak memories, for vividly recollected vs. familiar memories, for memories retrieved with high vs. low confidence. We introduce a model of episodic memory retrieval that characterizes contributions of posterior parietal cortex.

A critical evaluation of monkey models of amnesia and dementia.

PubMed

Ridley, R M; Baker, H F

1991-01-01

In this review we consider various models of amnesia and dementia in monkeys and examine the validity of such models. In Section 2 we describe the various types of memory tests (tasks) available for use with monkeys and discuss the extent to which these tasks assess different facets of memory according to present theories of human memory. We argue that the rules which govern correct task performance are best regarded as a form of semantic rather than procedural memory, and that when information about stimulus attributes or reward associations is stored long-term then that knowledge is semantic. The demonstration of episodic memory in monkeys is problematic and the term recognition memory has been used too loosely. In particular, it is difficult to dissociate episodic memory for stimulus events from the use of semantic memory for the rule of the task, since dysfunction of either can produce impairment on performance of the same task. Tasks can also be divided into those which assess memory for stimulus-reward associations (evaluative memory) and those which tax stimulus-response associations including spatial and conditional responding (non-evaluative memory). This dissociation cuts across the distinction between semantic and episodic memory. In Section 3 we examine the usefulness of the classification of tasks described in Section 2 in clarifying our understanding of the contribution of the temporal lobes and the cholinergic system to memory. We conclude that evaluative and non-evaluative memory are mediated by separate parallel systems involving the amygdala and hippocampus, respectively.

Neurophysiological indices of perceptual object priming in the absence of explicit recognition memory.

PubMed

Harris, Jill D; Cutmore, Tim R H; O'Gorman, John; Finnigan, Simon; Shum, David

2009-02-01

The aim of this study was to identify ERP correlates of perceptual object priming that are insensitive to factors affecting explicit, episodic memory. EEG was recorded from 21 participants while they performed a visual object recognition test on a combination of unstudied items and old items that were previously encountered during either a 'deep' or 'shallow' levels-of-processing (LOP) study task. The results demonstrated a midline P150 old/new effect which was sensitive only to objects' old/new status and not to the accuracy of recognition responses to old items, or to the LOP manipulation. Similar outcomes were observed for the subsequent P200 and N400 effects, the former of which had a parietal scalp maximum and the latter, a broadly distributed topography. In addition an LPC old/new effect typical of those reported in past ERP recognition studies was observed. These outcomes support the proposal that the P150 effect is reflective of perceptual object priming and moreover, provide novel evidence that this and the P200 effect are independent of explicit recognition memory process(es).

Rethinking Familiarity: Remember/Know Judgments in Free Recall

PubMed Central

Mickes, Laura; Seale-Carlisle, Travis M.; Wixted, John T.

2013-01-01

Although frequently used with recognition, a few studies have used the Remember/Know procedure with free recall. In each case, participants gave Know judgments to a significant number of recalled items (items that were presumably not remembered on the basis of familiarity). What do these Know judgments mean? We investigated this issue using a source memory/free-recall procedure. For each word that was recalled, participants were asked to (a) make a confidence rating on a 5-point scale, (b) make a Remember/Know judgment, and (c) recollect a source detail. The large majority of both Remember judgments and Know judgments were made with high confidence and high accuracy, but source memory was nevertheless higher for Remember judgments than for Know judgments. These source memory results correspond to what is found using recognition, and they raise the possibility that Know judgments in free recall identify the cue-dependent retrieval of item-only information from an episodic memory search set. In agreement with this idea, we also found that the temporal dynamics of free recall were similar for high-confidence Remember and high-confidence Know judgments (as if both judgments reflected retrieval from the same search set). If Know judgments in free recall do in fact reflect the episodic retrieval of item-only information, it seems reasonable to suppose that the same might be true of high-confidence Know judgments in recognition. If so, then a longstanding debate about the role of the hippocampus in recollection and familiarity may have a natural resolution. PMID:23637470

Active retrieval facilitates across-episode binding by modulating the content of memory.

PubMed

Bridge, Donna J; Voss, Joel L

2014-10-01

The contents of memory can be updated when information from the current episode is bound with content retrieved from previous episodes. Little is known regarding factors that determine the memory content that is subject to this across-episode binding. We tested whether across-episode binding preferentially occurs for memory content that is currently "active" and identified relevant neural correlates. After studying objects at specific locations on scene backgrounds, subjects performed one of two retrieval tasks for the objects on different scene backgrounds. In an active condition, subjects recalled object locations, whereas subjects merely dragged objects to predetermined locations in a passive condition. Immediately following each object-location retrieval event, a novel face appeared on a blank screen. We hypothesized that the original episode content would be active in memory during face encoding in the active condition, but not in the passive condition (despite seeing the same content in both conditions). A ramification of the active condition would thus be preferential binding of original episode content to novel faces, with no such across-episode binding in the passive condition. Indeed, memory for faces was better when tested on the original background scenes in the active relative to passive condition, indicating that original episode content was bound with the active condition faces, whereas this occurred to a lesser extent for the passive condition faces. Likewise, early-onset negative ERP effects reflected binding of the face to the original episode content in the active but not the passive condition. In contrast, binding in the passive condition occurred only when faces were physically displayed on the original scenes during recognition testing, and a very similar early-onset negative ERP effect signaled binding in this condition. ERP correlates of binding were thus similar for across-episode and within-episode binding (and were distinct from other encoding and retrieval ERP signals in both cases), indicating that active retrieval modulated when binding occurred, not the nature of the binding process per se. These results suggest that active retrieval promotes binding of new information with contents of memory, whereas without active retrieval, these unrelated pieces of information might be bound only when they are physically paired. Copyright © 2014 Elsevier Ltd. All rights reserved.

Differences in binding and monitoring mechanisms contribute to lifespan age differences in false memory.

PubMed

Fandakova, Yana; Shing, Yee Lee; Lindenberger, Ulman

2013-10-01

Based on a 2-component framework of episodic memory development across the lifespan (Shing & Lindenberger, 2011), we examined the contribution of memory-related binding and monitoring processes to false memory susceptibility in childhood and old age. We administered a repeated continuous recognition task to children (N = 20, 10-12 years), younger adults (N = 20, 20-27 years), and older adults (N = 21, 68-76 years). Participants saw the same set of unrelated word pairs in 3 consecutive runs and their task was to identify pair reoccurrences within runs. Across runs, correct detection of repeated pairs decreased in children only, whereas false recognition of lure pairs showed a greater increase in older adults than in children or younger adults. False recognition of rearranged pairs decreased across runs for all participants. This decrease was most pronounced in children, in particular for high-confidence memory errors. We conclude that memory binding mechanisms are sufficiently developed in children to facilitate memory monitoring and reduce false memory for associative information. In contrast, older adults show senescent impairments in both binding and monitoring mechanisms that both contribute to elevated illusory recollections in old age. We conclude that binding and monitoring processes during memory performance follow different developmental trajectories from childhood to old age.

A functional magnetic resonance imaging investigation of episodic memory after traumatic brain injury.

PubMed

Russell, Kathryn C; Arenth, Patricia M; Scanlon, Joelle M; Kessler, Lauren J; Ricker, Joseph H

2011-06-01

Traumatic brain injury often negatively impacts episodic memory; however, studies of the neural substrates of this impairment have been limited. In this study, both encoding and recognition of visually presented stimuli were examined with functional magnetic resonance imaging. Twelve adults with chronic complicated mild, moderate, and severe injuries were compared with a matched group of 12 controls. Behavioral task performance did not differentiate the groups. During neuroimaging, however, the group of individuals with traumatic brain injury exhibited increased activation, as well as increased bilaterality and dispersion as compared to controls. Findings are discussed in terms of increased resource recruitment.

Egocentric-updating during navigation facilitates episodic memory retrieval.

PubMed

Gomez, Alice; Rousset, Stéphane; Baciu, Monica

2009-11-01

Influential models suggest that spatial processing is essential for episodic memory [O'Keefe, J., & Nadel, L. (1978). The hippocampus as a cognitive map. London: Oxford University Press]. However, although several types of spatial relations exist, such as allocentric (i.e. object-to-object relations), egocentric (i.e. static object-to-self relations) or egocentric updated on navigation information (i.e. self-to-environment relations in a dynamic way), usually only allocentric representations are described as potentially subserving episodic memory [Nadel, L., & Moscovitch, M. (1998). Hippocampal contributions to cortical plasticity. Neuropharmacology, 37(4-5), 431-439]. This study proposes to confront the allocentric representation hypothesis with an egocentric updated with self-motion representation hypothesis. In the present study, we explored retrieval performance in relation to these two types of spatial processing levels during learning. Episodic remembering has been assessed through Remember responses in a recall and in a recognition task, combined with a "Remember-Know-Guess" paradigm [Gardiner, J. M. (2001). Episodic memory and autonoetic consciousness: A first-person approach. Philosophical Transactions of the Royal Society B: Biological Sciences, 356(1413), 1351-1361] to assess the autonoetic level of responses. Our results show that retrieval performance was significantly higher when encoding was performed in the egocentric-updated condition. Although egocentric updated with self-motion and allocentric representations are not mutually exclusive, these results suggest that egocentric updating processing facilitates remember responses more than allocentric processing. The results are discussed according to Burgess and colleagues' model of episodic memory [Burgess, N., Becker, S., King, J. A., & O'Keefe, J. (2001). Memory for events and their spatial context: models and experiments. Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences, 356(1413), 1493-1503].

Sex-dependent dissociation between emotional appraisal and memory: a large-scale behavioral and fMRI study.

PubMed

Spalek, Klara; Fastenrath, Matthias; Ackermann, Sandra; Auschra, Bianca; Coynel, David; Frey, Julia; Gschwind, Leo; Hartmann, Francina; van der Maarel, Nadine; Papassotiropoulos, Andreas; de Quervain, Dominique; Milnik, Annette

2015-01-21

Extensive evidence indicates that women outperform men in episodic memory tasks. Furthermore, women are known to evaluate emotional stimuli as more arousing than men. Because emotional arousal typically increases episodic memory formation, the females' memory advantage might be more pronounced for emotionally arousing information than for neutral information. Here, we report behavioral data from 3398 subjects, who performed picture rating and memory tasks, and corresponding fMRI data from up to 696 subjects. We were interested in the interaction between sex and valence category on emotional appraisal, memory performances, and fMRI activity. The behavioral results showed that females evaluate in particular negative (p < 10(-16)) and positive (p = 2 × 10(-4)), but not neutral pictures, as emotionally more arousing (pinteraction < 10(-16)) than males. However, in the free recall females outperformed males not only in positive (p < 10(-16)) and negative (p < 5 × 10(-5)), but also in neutral picture recall (p < 3.4 × 10(-8)), with a particular advantage for positive pictures (pinteraction < 4.4 × 10(-10)). Importantly, females' memory advantage during free recall was absent in a recognition setting. We identified activation differences in fMRI, which corresponded to the females' stronger appraisal of especially negative pictures, but no activation differences that reflected the interaction effect in the free recall memory task. In conclusion, females' valence-category-specific memory advantage is only observed in a free recall, but not a recognition setting and does not depend on females' higher emotional appraisal. Copyright © 2015 the authors 0270-6474/15/350920-16$15.00/0.

Some Memories are Odder than Others: Judgments of Episodic Oddity Violate Known Decision Rules

PubMed Central

O’Connor, Akira R.; Guhl, Emily N.; Cox, Justin C.; Dobbins, Ian G.

2011-01-01

Current decision models of recognition memory are based almost entirely on one paradigm, single item old/new judgments accompanied by confidence ratings. This task results in receiver operating characteristics (ROCs) that are well fit by both signal-detection and dual-process models. Here we examine an entirely new recognition task, the judgment of episodic oddity, whereby participants select the mnemonically odd members of triplets (e.g., a new item hidden among two studied items). Using the only two known signal-detection rules of oddity judgment derived from the sensory perception literature, the unequal variance signal-detection model predicted that an old item among two new items would be easier to discover than a new item among two old items. In contrast, four separate empirical studies demonstrated the reverse pattern: triplets with two old items were the easiest to resolve. This finding was anticipated by the dual-process approach as the presence of two old items affords the greatest opportunity for recollection. Furthermore, a bootstrap-fed Monte Carlo procedure using two independent datasets demonstrated that the dual-process parameters typically observed during single item recognition correctly predict the current oddity findings, whereas unequal variance signal-detection parameters do not. Episodic oddity judgments represent a case where dual- and single-process predictions qualitatively diverge and the findings demonstrate that novelty is “odder” than familiarity. PMID:22833695

Neural correlates of confidence during item recognition and source memory retrieval: evidence for both dual-process and strength memory theories.

PubMed

Hayes, Scott M; Buchler, Norbou; Stokes, Jared; Kragel, James; Cabeza, Roberto

2011-12-01

Although the medial-temporal lobes (MTL), PFC, and parietal cortex are considered primary nodes in the episodic memory network, there is much debate regarding the contributions of MTL, PFC, and parietal subregions to recollection versus familiarity (dual-process theory) and the feasibility of accounts on the basis of a single memory strength process (strength theory). To investigate these issues, the current fMRI study measured activity during retrieval of memories that differed quantitatively in terms of strength (high vs. low-confidence trials) and qualitatively in terms of recollection versus familiarity (source vs. item memory tasks). Support for each theory varied depending on which node of the episodic memory network was considered. Results from MTL best fit a dual-process account, as a dissociation was found between a right hippocampal region showing high-confidence activity during the source memory task and bilateral rhinal regions showing high-confidence activity during the item memory task. Within PFC, several left-lateralized regions showed greater activity for source than item memory, consistent with recollective orienting, whereas a right-lateralized ventrolateral area showed low-confidence activity in both tasks, consistent with monitoring processes. Parietal findings were generally consistent with strength theory, with dorsal areas showing low-confidence activity and ventral areas showing high-confidence activity in both tasks. This dissociation fits with an attentional account of parietal functions during episodic retrieval. The results suggest that both dual-process and strength theories are partly correct, highlighting the need for an integrated model that links to more general cognitive theories to account for observed neural activity during episodic memory retrieval.

Neural Correlates of Confidence during Item Recognition and Source Memory Retrieval: Evidence for Both Dual-process and Strength Memory Theories

PubMed Central

Hayes, Scott M.; Buchler, Norbou; Stokes, Jared; Kragel, James; Cabeza, Roberto

2012-01-01

Although the medial-temporal lobes (MTL), PFC, and parietal cortex are considered primary nodes in the episodic memory network, there is much debate regarding the contributions of MTL, PFC, and parietal subregions to recollection versus familiarity (dual-process theory) and the feasibility of accounts on the basis of a single memory strength process (strength theory). To investigate these issues, the current fMRI study measured activity during retrieval of memories that differed quantitatively in terms of strength (high vs. low-confidence trials) and qualitatively in terms of recollection versus familiarity (source vs. item memory tasks). Support for each theory varied depending on which node of the episodic memory network was considered. Results from MTL best fit a dual-process account, as a dissociation was found between a right hippocampal region showing high-confidence activity during the source memory task and bilateral rhinal regions showing high-confidence activity during the item memory task. Within PFC, several left-lateralized regions showed greater activity for source than item memory, consistent with recollective orienting, whereas a right-lateralized ventrolateral area showed low-confidence activity in both tasks, consistent with monitoring processes. Parietal findings were generally consistent with strength theory, with dorsal areas showing low-confidence activity and ventral areas showing high-confidence activity in both tasks. This dissociation fits with an attentional account of parietal functions during episodic retrieval. The results suggest that both dual-process and strength theories are partly correct, highlighting the need for an integrated model that links to more general cognitive theories to account for observed neural activity during episodic memory retrieval. PMID:21736454

Impaired cue identification and intention retrieval underlie prospective memory deficits in patients with first-episode schizophrenia.

PubMed

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

2017-03-01

Schizophrenia is associated with impairment in prospective memory, the ability to remember to carry out an intended action in the future. It has been established that cue identification (detection of the cue event signaling that an intended action should be performed) and intention retrieval (retrieval of an intention from long-term memory following the recognition of a prospective cue) are two important processes underlying prospective memory. The purpose of this study was to examine prospective memory deficit and underlying cognitive processes in patients with first-episode schizophrenia. This study examined cue identification and intention retrieval components of event-based prospective memory using a dual-task paradigm in 30 patients with first-episode schizophrenia and 30 healthy controls. All participants were also administered a set of tests assessing working memory and retrospective memory. Both cue identification and intention retrieval were impaired in patients with first-episode schizophrenia compared with healthy controls ( ps < 0.05), with a large effect size for cue identification (Cohen's d = 0.98) and a medium effect size for intention retrieval (Cohen's d = 0.62). After controlling for working memory and retrospective memory, the difference in cue identification between patients and healthy controls remained significant. However, the difference in intention retrieval between the two groups was no longer significant. In addition, there was a significant inverse relationship between cue identification and negative symptoms ( r = -0.446, p = 0.013) in the patient group. These findings suggest that both cue identification and intention retrieval in event-based prospective memory are impaired in patients with first-episode schizophrenia. Cue identification and intention retrieval could be potentially used as biomarkers for early detection and treatment prognosis of schizophrenia. In addition, addressing cue identification deficit through cognitive enhancement training may potentially improve negative symptoms as well.

Extra-hippocampal subcortical limbic involvement predicts episodic recall performance in multiple sclerosis.

PubMed

Dineen, Robert A; Bradshaw, Christopher M; Constantinescu, Cris S; Auer, Dorothee P

2012-01-01

Episodic memory impairment is a common but poorly-understood phenomenon in multiple sclerosis (MS). We aim to establish the relative contributions of reduced integrity of components of the extended hippocampal-diencephalic system to memory performance in MS patients using quantitative neuroimaging. 34 patients with relapsing-remitting MS and 24 healthy age-matched controls underwent 3 T MRI including diffusion tensor imaging and 3-D T1-weighted volume acquisition. Manual fornix regions-of-interest were used to derive fornix fractional anisotropy (FA). Normalized hippocampal, mammillary body and thalamic volumes were derived by manual segmentation. MS subjects underwent visual recall, verbal recall, verbal recognition and verbal fluency assessment. Significant differences between MS patients and controls were found for fornix FA (0.38 vs. 0.46, means adjusted for age and fornix volume, P<.0005) and mammillary body volumes (age-adjusted means 0.114 ml vs. 0.126 ml, P<.023). Multivariate regression analysis identified fornix FA and mammillary bodies as predictor of visual recall (R(2) = .31, P = .003, P = .006), and thalamic volume as predictive of verbal recall (R(2) = .37, P<.0005). No limbic measures predicted verbal recognition or verbal fluency. These findings indicate that structural and ultrastructural alterations in subcortical limbic components beyond the hippocampus predict performance of episodic recall in MS patients with mild memory dysfunction.

Levels-of-Processing Effect on Frontotemporal Function in Schizophrenia During Word Encoding and Recognition

PubMed Central

Ragland, J. Daniel; Gur, Ruben C.; Valdez, Jeffrey N.; Loughead, James; Elliott, Mark; Kohler, Christian; Kanes, Stephen; Siegel, Steven J.; Moelter, Stephen T.; Gur, Raquel E.

2015-01-01

Objective Patients with schizophrenia improve episodic memory accuracy when given organizational strategies through levels-of-processing paradigms. This study tested if improvement is accompanied by normalized frontotemporal function. Method Event-related blood-oxygen-level-dependent functional magnetic resonance imaging (fMRI) was used to measure activation during shallow (perceptual) and deep (semantic) word encoding and recognition in 14 patients with schizophrenia and 14 healthy comparison subjects. Results Despite slower and less accurate overall word classification, the patients showed normal levels-of-processing effects, with faster and more accurate recognition of deeply processed words. These effects were accompanied by left ventrolateral prefrontal activation during encoding in both groups, although the thalamus, hippocampus, and lingual gyrus were overactivated in the patients. During word recognition, the patients showed overactivation in the left frontal pole and had a less robust right prefrontal response. Conclusions Evidence of normal levels-of-processing effects and left prefrontal activation suggests that patients with schizophrenia can form and maintain semantic representations when they are provided with organizational cues and can improve their word encoding and retrieval. Areas of overactivation suggest residual inefficiencies. Nevertheless, the effect of teaching organizational strategies on episodic memory and brain function is a worthwhile topic for future interventional studies. PMID:16199830

Explicit and spontaneous retrieval of emotional scenes: electrophysiological correlates.

PubMed

Weymar, Mathias; Bradley, Margaret M; El-Hinnawi, Nasryn; Lang, Peter J

2013-10-01

When event-related potentials (ERP) are measured during a recognition task, items that have previously been presented typically elicit a larger late (400-800 ms) positive potential than new items. Recent data, however, suggest that emotional, but not neutral, pictures show ERP evidence of spontaneous retrieval when presented in a free-viewing task (Ferrari, Bradley, Codispoti, Karlsson, & Lang, 2012). In two experiments, we further investigated the brain dynamics of implicit and explicit retrieval. In Experiment 1, brain potentials were measured during a semantic categorization task, which did not explicitly probe episodic memory, but which, like a recognition task, required an active decision and a button press, and were compared to those elicited during recognition and free viewing. Explicit recognition prompted a late enhanced positivity for previously presented, compared with new, pictures regardless of hedonic content. In contrast, only emotional pictures showed an old-new difference when the task did not explicitly probe episodic memory, either when making an active categorization decision regarding picture content, or when simply viewing pictures. In Experiment 2, however, neutral pictures did prompt a significant old-new ERP difference during subsequent free viewing when emotionally arousing pictures were not included in the encoding set. These data suggest that spontaneous retrieval is heightened for salient cues, perhaps reflecting heightened attention and elaborative processing at encoding.

Explicit and spontaneous retrieval of emotional scenes: Electrophysiological correlates

PubMed Central

Weymar, Mathias; Bradley, Margaret M.; El-Hinnawi, Nasryn; Lang, Peter J.

2014-01-01

When event-related potentials are measured during a recognition task, items that have previously been presented typically elicit a larger late (400–800 ms) positive potential than new items. Recent data, however, suggest that emotional, but not neutral, pictures show ERP evidence of spontaneous retrieval when presented in a free-viewing task (Ferrari, Bradley, Codispoti & Lang, 2012). In two experiments, we further investigated the brain dynamics of implicit and explicit retrieval. In Experiment 1, brain potentials were measured during a semantic categorization task, which did not explicitly probe episodic memory, but which, like a recognition task, required an active decision and a button press, and were compared to those elicited during recognition and free viewing. Explicit recognition prompted a late enhanced positivity for previously presented, compared to new, pictures regardless of hedonic content. In contrast, only emotional pictures showed an old-new difference when the task did not explicitly probe episodic memory, either when either making an active categorization decision regarding picture content, or when simply viewing pictures. In Experiment 2, however, neutral pictures did prompt a significant old-new ERP difference during subsequent free viewing when emotionally arousing pictures were not included in the encoding set. These data suggest that spontaneous retrieval is heightened for salient cues, perhaps reflecting heightened attention and elaborative processing at encoding. PMID:23795588

Retrieval and Monitoring Processes during Visual Working Memory: An ERP Study of the Benefit of Visual Semantics

PubMed Central

Orme, Elizabeth; Brown, Louise A.; Riby, Leigh M.

2017-01-01

In this study, we examined electrophysiological indices of episodic remembering whilst participants recalled novel shapes, with and without semantic content, within a visual working memory paradigm. The components of interest were the parietal episodic (PE; 400–800 ms) and late posterior negativity (LPN; 500–900 ms), as these have previously been identified as reliable markers of recollection and post-retrieval monitoring, respectively. Fifteen young adults completed a visual matrix patterns task, assessing memory for low and high semantic visual representations. Matrices with either low semantic or high semantic content (containing familiar visual forms) were briefly presented to participants for study (1500 ms), followed by a retention interval (6000 ms) and finally a same/different recognition phase. The event-related potentials of interest were tracked from the onset of the recognition test stimuli. Analyses revealed equivalent amplitude for the earlier PE effect for the processing of both low and high semantic stimulus types. However, the LPN was more negative-going for the processing of the low semantic stimuli. These data are discussed in terms of relatively ‘pure’ and complete retrieval of high semantic items, where support can readily be recruited from semantic memory. However, for the low semantic items additional executive resources, as indexed by the LPN, are recruited when memory monitoring and uncertainty exist in order to recall previously studied items more effectively. PMID:28725203

Retrieval and Monitoring Processes during Visual Working Memory: An ERP Study of the Benefit of Visual Semantics.

PubMed

Orme, Elizabeth; Brown, Louise A; Riby, Leigh M

2017-01-01

In this study, we examined electrophysiological indices of episodic remembering whilst participants recalled novel shapes, with and without semantic content, within a visual working memory paradigm. The components of interest were the parietal episodic (PE; 400-800 ms) and late posterior negativity (LPN; 500-900 ms), as these have previously been identified as reliable markers of recollection and post-retrieval monitoring, respectively. Fifteen young adults completed a visual matrix patterns task, assessing memory for low and high semantic visual representations. Matrices with either low semantic or high semantic content (containing familiar visual forms) were briefly presented to participants for study (1500 ms), followed by a retention interval (6000 ms) and finally a same/different recognition phase. The event-related potentials of interest were tracked from the onset of the recognition test stimuli. Analyses revealed equivalent amplitude for the earlier PE effect for the processing of both low and high semantic stimulus types. However, the LPN was more negative-going for the processing of the low semantic stimuli. These data are discussed in terms of relatively 'pure' and complete retrieval of high semantic items, where support can readily be recruited from semantic memory. However, for the low semantic items additional executive resources, as indexed by the LPN, are recruited when memory monitoring and uncertainty exist in order to recall previously studied items more effectively.

How landmark suitability shapes recognition memory signals for objects in the medial temporal lobes.

PubMed

Martin, Chris B; Sullivan, Jacqueline A; Wright, Jessey; Köhler, Stefan

2018-02-01

A role of perirhinal cortex (PrC) in recognition memory for objects has been well established. Contributions of parahippocampal cortex (PhC) to this function, while documented, remain less well understood. Here, we used fMRI to examine whether the organization of item-based recognition memory signals across these two structures is shaped by object category, independent of any difference in representing episodic context. Guided by research suggesting that PhC plays a critical role in processing landmarks, we focused on three categories of objects that differ from each other in their landmark suitability as confirmed with behavioral ratings (buildings > trees > aircraft). Participants made item-based recognition-memory decisions for novel and previously studied objects from these categories, which were matched in accuracy. Multi-voxel pattern classification revealed category-specific item-recognition memory signals along the long axis of PrC and PhC, with no sharp functional boundaries between these structures. Memory signals for buildings were observed in the mid to posterior extent of PhC, signals for trees in anterior to posterior segments of PhC, and signals for aircraft in mid to posterior aspects of PrC and the anterior extent of PhC. Notably, item-based memory signals for the category with highest landmark suitability ratings were observed only in those posterior segments of PhC that also allowed for classification of landmark suitability of objects when memory status was held constant. These findings provide new evidence in support of the notion that item-based memory signals for objects are not limited to PrC, and that the organization of these signals along the longitudinal axis that crosses PrC and PhC can be captured with reference to landmark suitability. Copyright © 2017 Elsevier Inc. All rights reserved.

Patterns of False Memory in Patients with Huntington's Disease.

PubMed

Chen, I-Wen; Chen, Chiung-Mei; Wu, Yih-Ru; Hua, Mau-Sun

2017-06-01

Increased false memory recognition in patients with Huntington's disease (HD) has been widely reported; however, the underlying memory constructive processes remain unclear. The present study explored gist memory, item-specific memory, and monitoring ability in patients with HD. Twenty-five patients (including 13 patients with mild HD and 12 patients with moderate-to-severe HD) and 30 healthy comparison participants (HC) were recruited. We used the Deese-Roediger-McDermott (DRM) paradigm to investigate participants' false recognition patterns, along with neuropsychological tests to assess general cognitive function. Both mild and moderate-to-severe patients with HD showed significant executive functioning and episodic memory impairment. On the DRM tasks, both HD patient groups showed significantly impaired performance in tasks assessing unrelated false recognition and item-specific memory as compared to the HC group; moderate-to-severe patients performed more poorly than mild patients did. Only moderate-severe patients exhibited significantly poorer related false recognition index scores than HCs in the verbal DRM task; performance of HD patient groups was comparable to the HC group on the pictorial DRM task. It appears that diminished verbatim memory and monitoring ability are early signs of cognitive decline during the HD course. Conversely, gist memory is relatively robust, with only partial decline during advanced-stage HD. Our findings suggest that medial temporal lobe function is relatively preserved compared to that of frontal-related structures in early HD. Thus, gist-based memory rehabilitation programs might be beneficial for patients with HD. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The impact of threat of shock-induced anxiety on memory encoding and retrieval

PubMed Central

Bolton, Sorcha

2017-01-01

Anxiety disorders are the most common mental health disorders, and daily transient feelings of anxiety (or “stress”) are ubiquitous. However, the precise impact of both transient and pathological anxiety on higher-order cognitive functions, including short- and long-term memory, is poorly understood. A clearer understanding of the anxiety–memory relationship is important as one of the core symptoms of anxiety, most prominently in post-traumatic stress disorder (PTSD), is intrusive reexperiencing of traumatic events in the form of vivid memories. This study therefore aimed to examine the impact of induced anxiety (threat of shock) on memory encoding and retrieval. Eighty-six healthy participants completed tasks assessing: visuospatial working memory, verbal recognition, face recognition, and associative memory. Critically, anxiety was manipulated within-subjects: information was both encoded and retrieved under threat of shock and safe (no shock) conditions. Results revealed that visuospatial working memory was enhanced when information was encoded and subsequently retrieved under threat, and that threat impaired the encoding of faces regardless of the condition in which it was retrieved. Episodic memory and verbal short-term recognition were, however, unimpaired. These findings indicate that transient anxiety in healthy individuals has domain-specific, rather than domain-general, impacts on memory. Future studies would benefit from expanding these findings into anxiety disorder patients to delineate the differences between adaptive and maladaptive responding. PMID:28916628

Emotional memory: No source memory without old-new recognition.

PubMed

Bell, Raoul; Mieth, Laura; Buchner, Axel

2017-02-01

Findings reported in the memory literature suggest that the emotional components of an encoding episode can be dissociated from nonemotional memory. In particular, it has been found that the previous association with threatening events can be retrieved in aversive conditioning even in the absence of item identification. In the present study, we test whether emotional source memory can be independent of item recognition. Participants saw pictures of snakes paired with threatening and nonthreatening context information (poisonousness or nonpoisonousness). In the source memory test, participants were required to remember whether a snake was associated with poisonousness or nonpoisonousness. A simple extension of a well-established multinomial source monitoring model was used to measure source memory for unrecognized items. By using this model, it was possible to assess directly whether participants were able to associate a previously seen snake with poisonousness or nonpoisonousness even if the snake itself was not recognized as having been presented during the experiment. In 3 experiments, emotional source memory was only found for recognized items. While source memory for recognized items differed between emotional and nonemotional information, source memory for unrecognized items was equally absent for emotional and nonemotional information. We conclude that emotional context information is bound to item representations and cannot be retrieved in the absence of item recognition. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Reversibility of object recognition but not spatial memory impairment following binge-like alcohol exposure in rats

PubMed Central

Cippitelli, Andrea; Zook, Michelle; Bell, Lauren; Damadzic, Ruslan; Eskay, Robert L.; Schwandt, Melanie; Heilig, Markus

2010-01-01

Excessive alcohol use leads to neurodegeneration in several brain structures including the hippocampal dentate gyrus and the entorhinal cortex. Cognitive deficits that result are among the most insidious and debilitating consequences of alcoholism. The object exploration task (OET) provides a sensitive measurement of spatial memory impairment induced by hippocampal and cortical damage. In this study, we examine whether the observed neurotoxicity produced by a 4-day binge ethanol treatment results in long-term memory impairment by observing the time course of reactions to spatial change (object configuration) and non-spatial change (object recognition). Wistar rats were assessed for their abilities to detect spatial configuration in the OET at 1 week and 10 weeks following the ethanol treatment, in which ethanol groups received 9–15 g/kg/day and achieved blood alcohol levels over 300 mg/dl. At 1 week, results indicated that the binge alcohol treatment produced impairment in both spatial memory and non-spatial object recognition performance. Unlike the controls, ethanol treated rats did not increase the duration or number of contacts with the displaced object in the spatial memory task, nor did they increase the duration of contacts with the novel object in the object recognition task. After 10 weeks, spatial memory remained impaired in the ethanol treated rats but object recognition ability was recovered. Our data suggest that episodes of binge-like alcohol exposure result in long-term and possibly permanent impairments in memory for the configuration of objects during exploration, whereas the ability to detect non-spatial changes is only temporarily affected. PMID:20849966

Age-related differences in associative memory: the role of sensory decline.

PubMed

Naveh-Benjamin, Moshe; Kilb, Angela

2014-09-01

Numerous studies show age-related decline in episodic memory. One of the explanations for this decline points to older adults' deficit in associative memory, reflecting the difficulties they have in binding features of episodes into cohesive entities and retrieving these bindings. Here, we evaluate the degree to which this deficit may be mediated by sensory loss associated with increased age. In 2 experiments, young adults studied word pairs that were degraded at encoding either visually (Experiment 1) or auditorily (Experiment 2). We then tested their memory for both the component words and the associations with recognition tests. For both experiments, young adults under nondegraded conditions showed an advantage in associative over item memory, relative to a group of older adults. In contrast, under perceptually degraded conditions younger adults performed similarly to the older adults who were tested under nondegraded conditions. More specifically, under perceptual degradation, young adults' associative memory declined and their component memory improved somewhat, resulting in an associative deficit, similar to that shown by older adults. This evidence is consistent with a sensory acuity decline in old age being one mediator in the associative deficit of older adults. These results broaden our understanding of age-related memory changes and how sensory and cognitive processes interact to shape these changes. The theoretical implications of these results are discussed with respect to mechanisms underlying age-related changes in episodic memory and resource tradeoffs in the encoding of component and associative memory. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Depth of processing effects on neural correlates of memory encoding: relationship between findings from across- and within-task comparisons.

PubMed

Otten, L J; Henson, R N; Rugg, M D

2001-02-01

Neuroimaging studies have implicated the prefrontal cortex and medial temporal areas in the successful encoding of verbal material into episodic memory. The present study used event-related functional MRI to investigate whether the brain areas associated with successful episodic encoding of words in a semantic study task are a subset of those demonstrating depth of processing effects. In addition, we tested whether the brain areas associated with successful episodic encoding differ depending on the nature of the study task. At study, 15 volunteers were cued to make either animacy or alphabetical decisions about words. A recognition memory test including confidence judgements followed after a delay of 15 min. Prefrontal and medial temporal regions showed greater functional MRI activations for semantically encoded words relative to alphabetically encoded words. Two of these regions (left anterior hippocampus and left ventral inferior frontal gyrus) showed greater activation for semantically encoded words that were subsequently recognized confidently. However, other regions (left posterior hippocampus and right inferior frontal cortex) demonstrated subsequent memory effects, but not effects of depth of processing. Successful memory for alphabetically encoded words was also associated with greater activation in the left anterior hippocampus and left ventral inferior frontal gyrus. The findings suggest that episodic encoding for words in a semantic study task involves a subset of the regions activated by deep relative to shallow processing. The data provide little evidence that successful episodic encoding during a shallow study task depends upon regions different from those that support the encoding of deeply studied words. Instead, the findings suggest that successful episodic encoding during a shallow study task relies on a subset of the regions engaged during successful encoding in a deep task.

Selective attention and recognition: effects of congruency on episodic learning.

PubMed

Rosner, Tamara M; D'Angelo, Maria C; MacLellan, Ellen; Milliken, Bruce

2015-05-01

Recent research on cognitive control has focused on the learning consequences of high selective attention demands in selective attention tasks (e.g., Botvinick, Cognit Affect Behav Neurosci 7(4):356-366, 2007; Verguts and Notebaert, Psychol Rev 115(2):518-525, 2008). The current study extends these ideas by examining the influence of selective attention demands on remembering. In Experiment 1, participants read aloud the red word in a pair of red and green spatially interleaved words. Half of the items were congruent (the interleaved words had the same identity), and the other half were incongruent (the interleaved words had different identities). Following the naming phase, participants completed a surprise recognition memory test. In this test phase, recognition memory was better for incongruent than for congruent items. In Experiment 2, context was only partially reinstated at test, and again recognition memory was better for incongruent than for congruent items. In Experiment 3, all of the items contained two different words, but in one condition the words were presented close together and interleaved, while in the other condition the two words were spatially separated. Recognition memory was better for the interleaved than for the separated items. This result rules out an interpretation of the congruency effects on recognition in Experiments 1 and 2 that hinges on stronger relational encoding for items that have two different words. Together, the results support the view that selective attention demands for incongruent items lead to encoding that improves recognition.

Familiarity for Associations? A Test of the Domain Dichotomy Theory

ERIC Educational Resources Information Center

Harlow, Iain M.; Mackenzie, Graham; Donaldson, David I.

2010-01-01

Episodic recognition memory is mediated by functionally separable retrieval processes, notably familiarity (a general sense of prior exposure) and recollection (the retrieval of contextual details), whose relative engagement depends partly on the nature of the information being retrieved. Currently, the specific contribution of familiarity to…

ERP correlates of source memory: unitized source information increases familiarity-based retrieval.

PubMed

Diana, Rachel A; Van den Boom, Wijnand; Yonelinas, Andrew P; Ranganath, Charan

2011-01-07

Source memory tests typically require subjects to make decisions about the context in which an item was encoded and are thought to depend on recollection of details from the study episode. Although it is generally believed that familiarity does not contribute to source memory, recent behavioral studies have suggested that familiarity may also support source recognition when item and source information are integrated, or "unitized," during study (Diana, Yonelinas, and Ranganath, 2008). However, an alternative explanation of these behavioral findings is that unitization affects the manner in which recollection contributes to performance, rather than increasing familiarity-based source memory. To discriminate between these possibilities, we conducted an event-related potential (ERP) study testing the hypothesis that unitization increases the contribution of familiarity to source recognition. Participants studied associations between words and background colors using tasks that either encouraged or discouraged unitization. ERPs were recorded during a source memory test for background color. The results revealed two distinct neural correlates of source recognition: a frontally distributed positivity that was associated with familiarity-based source memory in the high-unitization condition only and a parietally distributed positivity that was associated with recollection-based source memory in both the high- and low-unitization conditions. The ERP and behavioral findings provide converging evidence for the idea that familiarity can contribute to source recognition, particularly when source information is encoded as an item detail. Copyright © 2010 Elsevier B.V. All rights reserved.

Neural activation and memory for natural scenes: Explicit and spontaneous retrieval.

PubMed

Weymar, Mathias; Bradley, Margaret M; Sege, Christopher T; Lang, Peter J

2018-05-06

Stimulus repetition elicits either enhancement or suppression in neural activity, and a recent fMRI meta-analysis of repetition effects for visual stimuli (Kim, 2017) reported cross-stimulus repetition enhancement in medial and lateral parietal cortex, as well as regions of prefrontal, temporal, and posterior cingulate cortex. Repetition enhancement was assessed here for repeated and novel scenes presented in the context of either an explicit episodic recognition task or an implicit judgment task, in order to study the role of spontaneous retrieval of episodic memories. Regardless of whether episodic memory was explicitly probed or not, repetition enhancement was found in medial posterior parietal (precuneus/cuneus), lateral parietal cortex (angular gyrus), as well as in medial prefrontal cortex (frontopolar), which did not differ by task. Enhancement effects in the posterior cingulate cortex were significantly larger during explicit compared to implicit task, primarily due to a lack of functional activity for new scenes. Taken together, the data are consistent with an interpretation that medial and (ventral) lateral parietal cortex are associated with spontaneous episodic retrieval, whereas posterior cingulate cortical regions may reflect task or decision processes. © 2018 Society for Psychophysiological Research.

Elements of person knowledge: Episodic recollection helps us to identify people but not to recognize their faces.

PubMed

MacKenzie, Graham; Donaldson, David I

2016-12-01

Faces automatically draw attention, allowing rapid assessments of personality and likely behaviour. How we respond to people is, however, highly dependent on whether we know who they are. According to face processing models person knowledge comes from an extended neural system that includes structures linked to episodic memory. Here we use scalp recorded brain signals to demonstrate the specific role of episodic memory processes during face processing. In two experiments we recorded Event-Related Potentials (ERPs) while participants made identify, familiar or unknown responses to famous faces. ERPs revealed neural signals previously associated with episodic recollection for identify but not familiar faces. These findings provide novel evidence suggesting that recollection is central to face processing, providing one source of person knowledge that can be used to moderate the initial impressions gleaned from the core neural system that supports face recognition. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Chronic and acute adenosine A2A receptor blockade prevents long-term episodic memory disruption caused by acute cannabinoid CB1 receptor activation.

PubMed

Mouro, Francisco M; Batalha, Vânia L; Ferreira, Diana G; Coelho, Joana E; Baqi, Younis; Müller, Christa E; Lopes, Luísa V; Ribeiro, Joaquim A; Sebastião, Ana M

2017-05-01

Cannabinoid-mediated memory impairment is a concern in cannabinoid-based therapies. Caffeine exacerbates cannabinoid CB 1 receptor (CB 1 R)-induced memory deficits through an adenosine A 1 receptor-mediated mechanism. We now evaluated how chronic or acute blockade of adenosine A 2A receptors (A 2A Rs) affects long-term episodic memory deficits induced by a single injection of a selective CB 1 R agonist. Long-term episodic memory was assessed by the novel object recognition (NOR) test. Mice received an intraperitoneal (i.p.) injection of the CB 1 /CB 2 receptor agonist WIN 55,212-2 (1 mg/kg) immediately after the NOR training, being tested for novelty recognition 24 h later. Anxiety levels were assessed by the Elevated Plus Maze test, immediately after the NOR. Mice were also tested for exploratory behaviour at the Open Field. For chronic A 2A R blockade, KW-6002 (istradefylline) (3 mg/kg/day) was administered orally for 30 days; acute blockade of A 2A Rs was assessed by i.p. injection of SCH 58261 (1 mg/kg) administered either together with WIN 55,212-2 or only 30 min before the NOR test phase. The involvement of CB 1 Rs was assessed by using the CB 1 R antagonist, AM251 (3 mg/kg, i.p.). WIN 55,212-2 caused a disruption in NOR, an action absent in mice also receiving AM251, KW-6002 or SCH 58261 during the encoding/consolidation phase; SCH 58251 was ineffective if present during retrieval only. No effects were detected in the Elevated Plus maze or Open Field Test. The finding that CB 1 R-mediated memory disruption is prevented by antagonism of adenosine A 2A Rs, highlights a possibility to prevent cognitive side effects when therapeutic application of CB 1 R drugs is desired. Copyright © 2017 Elsevier Ltd. All rights reserved.

Non-Interfering Effects of Active Post-Encoding Tasks on Episodic Memory Consolidation in Humans

PubMed Central

Varma, Samarth; Takashima, Atsuko; Krewinkel, Sander; van Kooten, Maaike; Fu, Lily; Medendorp, W. Pieter; Kessels, Roy P. C.; Daselaar, Sander M.

2017-01-01

So far, studies that investigated interference effects of post-learning processes on episodic memory consolidation in humans have used tasks involving only complex and meaningful information. Such tasks require reallocation of general or encoding-specific resources away from consolidation-relevant activities. The possibility that interference can be elicited using a task that heavily taxes our limited brain resources, but has low semantic and hippocampal related long-term memory processing demands, has never been tested. We address this question by investigating whether consolidation could persist in parallel with an active, encoding-irrelevant, minimally semantic task, regardless of its high resource demands for cognitive processing. We distinguish the impact of such a task on consolidation based on whether it engages resources that are: (1) general/executive, or (2) specific/overlapping with the encoding modality. Our experiments compared subsequent memory performance across two post-encoding consolidation periods: quiet wakeful rest and a cognitively demanding n-Back task. Across six different experiments (total N = 176), we carefully manipulated the design of the n-Back task to target general or specific resources engaged in the ongoing consolidation process. In contrast to previous studies that employed interference tasks involving conceptual stimuli and complex processing demands, we did not find any differences between n-Back and rest conditions on memory performance at delayed test, using both recall and recognition tests. Our results indicate that: (1) quiet, wakeful rest is not a necessary prerequisite for episodic memory consolidation; and (2) post-encoding cognitive engagement does not interfere with memory consolidation when task-performance has minimal semantic and hippocampally-based episodic memory processing demands. We discuss our findings with reference to resource and reactivation-led interference theories. PMID:28424596

DAT genotype modulates striatal processing and long-term memory for items associated with reward and punishment☆

PubMed Central

Wittmann, Bianca C.; Tan, Geoffrey C.; Lisman, John E.; Dolan, Raymond J.; Düzel, Emrah

2013-01-01

Previous studies have shown that appetitive motivation enhances episodic memory formation via a network including the substantia nigra/ventral tegmental area (SN/VTA), striatum and hippocampus. This functional magnetic resonance imaging (fMRI) study now contrasted the impact of aversive and appetitive motivation on episodic long-term memory. Cue pictures predicted monetary reward or punishment in alternating experimental blocks. One day later, episodic memory for the cue pictures was tested. We also investigated how the neural processing of appetitive and aversive motivation and episodic memory were modulated by dopaminergic mechanisms. To that end, participants were selected on the basis of their genotype for a variable number of tandem repeat polymorphism of the dopamine transporter (DAT) gene. The resulting groups were carefully matched for the 5-HTTLPR polymorphism of the serotonin transporter gene. Recognition memory for cues from both motivational categories was enhanced in participants homozygous for the 10-repeat allele of the DAT, the functional effects of which are not known yet, but not in heterozygous subjects. In comparison with heterozygous participants, 10-repeat homozygous participants also showed increased striatal activity for anticipation of motivational outcomes compared to neutral outcomes. In a subsequent memory analysis, encoding activity in striatum and hippocampus was found to be higher for later recognized items in 10-repeat homozygotes compared to 9/10-repeat heterozygotes. These findings suggest that processing of appetitive and aversive motivation in the human striatum involve the dopaminergic system and that dopamine plays a role in memory for both types of motivational information. In accordance with animal studies, these data support the idea that encoding of motivational events depends on dopaminergic processes in the hippocampus. PMID:23911780

Non-Interfering Effects of Active Post-Encoding Tasks on Episodic Memory Consolidation in Humans.

PubMed

Varma, Samarth; Takashima, Atsuko; Krewinkel, Sander; van Kooten, Maaike; Fu, Lily; Medendorp, W Pieter; Kessels, Roy P C; Daselaar, Sander M

2017-01-01

So far, studies that investigated interference effects of post-learning processes on episodic memory consolidation in humans have used tasks involving only complex and meaningful information. Such tasks require reallocation of general or encoding-specific resources away from consolidation-relevant activities. The possibility that interference can be elicited using a task that heavily taxes our limited brain resources, but has low semantic and hippocampal related long-term memory processing demands, has never been tested. We address this question by investigating whether consolidation could persist in parallel with an active, encoding-irrelevant, minimally semantic task, regardless of its high resource demands for cognitive processing. We distinguish the impact of such a task on consolidation based on whether it engages resources that are: (1) general/executive, or (2) specific/overlapping with the encoding modality. Our experiments compared subsequent memory performance across two post-encoding consolidation periods: quiet wakeful rest and a cognitively demanding n-Back task. Across six different experiments (total N = 176), we carefully manipulated the design of the n-Back task to target general or specific resources engaged in the ongoing consolidation process. In contrast to previous studies that employed interference tasks involving conceptual stimuli and complex processing demands, we did not find any differences between n-Back and rest conditions on memory performance at delayed test, using both recall and recognition tests. Our results indicate that: (1) quiet, wakeful rest is not a necessary prerequisite for episodic memory consolidation; and (2) post-encoding cognitive engagement does not interfere with memory consolidation when task-performance has minimal semantic and hippocampally-based episodic memory processing demands. We discuss our findings with reference to resource and reactivation-led interference theories.

[Emotional Memory and Electrocortical Activity in Schizophrenia].

PubMed

Lavoie, Marc E; Champagne, Julie; Glaser, Emma; Mendrek, Adrianna

Context Abnormal emotion processing is frequent in schizophrenia and affects social and functional outcome. Past event-related potential (ERP) research investigating processing of affective stimuli in schizophrenia was done mainly with facial expressions and revealed impaired facial emotion recognition in patients relative to control subjects. Experimentations involving fMRI with this group of patients, showed alteration of limbic and frontal regions in response to emotional unpleasant images, compared to neutral stimuli during a memory task. Other studies have also noted an increase in brain activity when the activation of the stimuli was high compared to low arousal stimuli. This may indicate a different sensitivity threshold to emotional arousal and emotional valence involving frontal pathways in these patients. But very few studies attempted to separate the contributions of emotional valence and arousal within an episodic memory protocol with ERP, in that population.Goal The aim of the current research is to investigate brain electro-cortical activity in schizophrenia in response to emotional images during an episodic memory task.Method ERP components were analyzed in 16 schizophrenic and 17 control participants matched for age, sex and intelligence. ERPs were obtained from 56 EEG electrodes. The tasks consisted in a classical episodic memory task that presented 100 repeated old and 100 new photographic images divided into four categories (unpleasant-high arousal, unpleasant-low arousal, pleasant-high arousal and pleasant-low arousal) selected from the International Affective Picture System. The N200, P300 and late positive component (LPC) mean amplitude, were analyzed using repeated-measure analyses of variance (MANOVA).Results Patients with schizophrenia and control subjects gave comparable subjective evaluations of arousal and valence. However, the frontal N200 and the P300 both showed an interaction of the group x memory x valence x hemisphere (F [1.32]=8.36; p <.01). Thus, this complex interaction denotes an increase of the episodic memory effect in the right hemisphere in response to unpleasant stimuli, with schizophrenic patients. With respect to the control group, there is also an increase of this memory effect in the right hemisphere, but in response to pleasant stimuli. The schizophrenic patients presented a smaller LPC memory effect, especially at the frontal region. More specifically, the frontal LPC was reduced, and the clinical group was less reactive to the emotional arousal content, compared to the control group.Discussion Altogether, our results revealed that while the subjective evaluation of emotional pictures is equivalent across groups, cerebral differences are present in schizophrenic patients during emotional recognition. N200 and P300 results in the frontal region suggest impaired selective attention and episodic memory to unpleasant stimuli in patients, while later processes related to conscious recollection (parietal LPC) are not affected with patients affected with schizophrenia.Conclusion This finding provides further support for the notion of a possible discrepancy between the subjective experience and the physiological expression of emotions in schizophrenia patients. Those results could open the door to new clinical research investigations in psychiatry, particularly in the comprehension of a relationship between frontal cortex vulnerability and episodic memory often present in psychosis.

Acute stress negatively affects object recognition early memory consolidation and memory retrieval unrelated to state-dependency.

PubMed

Nelissen, Ellis; Prickaerts, Jos; Blokland, Arjan

2018-06-01

It is well known that stress affects memory performance. However, there still appears to be inconstancy in literature about how acute stress affects the different stages of memory: acquisition, consolidation and retrieval. In this study, we exposed rats to acute stress and measured the effect on memory performance in the object recognition task as a measure for episodic memory. Stress was induced 30 min prior to the learning phase to affect acquisition, directly after the learning phase to affect consolidation, or 30 min before the retrieval phase to affect retrieval. Additionally, we induced stress both 30 min prior to the learning phase and 30 min prior to the retrieval phase to test whether the effects were related to state-dependency. As expected, we found that acute stress did not affect acquisition but had a negative impact on retrieval. To our knowledge, we are the first to show that early consolidation was negatively affected by acute stress. We also show that stress does not have a state-dependent effect on memory. Copyright © 2018 Elsevier B.V. All rights reserved.

Shaping memory accuracy by left prefrontal transcranial direct current stimulation.

PubMed

Zwissler, Bastian; Sperber, Christoph; Aigeldinger, Sina; Schindler, Sebastian; Kissler, Johanna; Plewnia, Christian

2014-03-12

Human memory is dynamic and flexible but is also susceptible to distortions arising from adaptive as well as pathological processes. Both accurate and false memory formation require executive control that is critically mediated by the left prefrontal cortex (PFC). Transcranial direct current stimulation (tDCS) enables noninvasive modulation of cortical activity and associated behavior. The present study reports that tDCS applied to the left dorsolateral PFC (dlPFC) shaped accuracy of episodic memory via polaritiy-specific modulation of false recognition. When applied during encoding of pictures, anodal tDCS increased whereas cathodal stimulation reduced the number of false alarms to lure pictures in subsequent recognition memory testing. These data suggest that the enhancement of excitability in the dlPFC by anodal tDCS can be associated with blurred detail memory. In contrast, activity-reducing cathodal tDCS apparently acted as a noise filter inhibiting the development of imprecise memory traces and reducing the false memory rate. Consistently, the largest effect was found in the most active condition (i.e., for stimuli cued to be remembered). This first evidence for a polarity-specific, activity-dependent effect of tDCS on false memory opens new vistas for the understanding and potential treatment of disturbed memory control.

Aging memories: differential decay of episodic memory components.

PubMed

Talamini, Lucia M; Gorree, Eva

2012-05-17

Some memories about events can persist for decades, even a lifetime. However, recent memories incorporate rich sensory information, including knowledge on the spatial and temporal ordering of event features, while old memories typically lack this "filmic" quality. We suggest that this apparent change in the nature of memories may reflect a preferential loss of hippocampus-dependent, configurational information over more cortically based memory components, including memory for individual objects. The current study systematically tests this hypothesis, using a new paradigm that allows the contemporaneous assessment of memory for objects, object pairings, and object-position conjunctions. Retention of each memory component was tested, at multiple intervals, up to 3 mo following encoding. The three memory subtasks adopted the same retrieval paradigm and were matched for initial difficulty. Results show differential decay of the tested episodic memory components, whereby memory for configurational aspects of a scene (objects' co-occurrence and object position) decays faster than memory for featured objects. Interestingly, memory requiring a visually detailed object representation decays at a similar rate as global object recognition, arguing against interpretations based on task difficulty and against the notion that (visual) detail is forgotten preferentially. These findings show that memories undergo qualitative changes as they age. More specifically, event memories become less configurational over time, preferentially losing some of the higher order associations that are dependent on the hippocampus for initial fast encoding. Implications for theories of long-term memory are discussed.

Effects of the Red Bull energy drink on cognitive function and mood in healthy young volunteers.

PubMed

Wesnes, Keith A; Brooker, Helen; Watson, Anthony W; Bal, Wendy; Okello, Edward

2017-02-01

The present study compared the cognitive and mood effects of two commercially available products, Red Bull energy drink 250 mL and Red Bull Sugarfree energy drink 250 mL, together with a matching placebo 250 mL. Twenty-four healthy young volunteers took part in a randomised, placebo controlled, double-blind, three-way cross-over study. Cognitive function was assessed using an integrated set of nine computerised tests of attention, working and episodic memory. On each study day the volunteers received a standardised breakfast prior to completing a baseline performance on cognitive tests and mood scales, followed by the consumption of the study drink. The cognitive tests and scales were then re-administered at 30, 60 and 90 min post-dose. Red Bull was found to produce significant improvements over both the Sugarfree version and the placebo drink on two composite scores from the six working and episodic memory tests; one combining the 12 accuracy measures from the six tasks and the other the average speed of correct responses from the working memory and episodic recognition memory tasks. These improvements were in the range of a medium effect size, which reflects a substantial enhancement to memory in young volunteers.

Differential involvement of episodic and face representations in ERP repetition effects.

PubMed

Jemel, Boutheina; Calabria, Marco; Delvenne, Jean-François; Crommelinck, Marc; Bruyer, Raymond

2003-03-03

The purpose of this study was to disentangle the contribution of episodic-perceptual from pre-existing memory representations of faces to repetition effects. ERPs were recorded to first and second presentations of same and different photos of famous and unfamiliar faces, in an incidental task where occasional non-targets had to be detected. Repetition of same and different photos of famous faces resulted in an N400 amplitude decrement. No such N400 repetition-induced attenuation was observed for unfamiliar faces. In addition, repetition of same photos of faces, and not different ones, gave rise to an early ERP repetition effect (starting at approximately 350 ms) with an occipito-temporal scalp distribution. Together, these results suggest that repetition effects depend on two temporally and may be neuro-functionally distinct loci, episode-based representation and face recognition units stored in long-term memory.

Effects of depressive disorder on false memory for emotional information.

PubMed

Yeh, Zai-Ting; Hua, Mau-Sun

2009-01-01

This study explored with a false memory paradigm whether (1) depressed patients revealed more false memories and (2) whether more negative false than positive false recognition existed in subjects with depressive disorders. Thirty-two patients suffering from a major depressive episode (DSM-IV criteria), and 30 age- and education-matched normal control subjects participated in this study. After the presentation of a list of positive, negative, and neutral association items in the learning phase, subjects were asked to give a yes/no response in the recognition phase. They were also asked to rate 81 recognition items with emotional valence scores. The results revealed more negative false memories in the clinical depression group than in the normal control group; however, we did not find more negative false memories than positive ones in patients. When compared with the normal group, a more conservative response criterion for positive items was evident in patient groups. It was also found that when compared with the normal group, the subjects in the depression group perceived the positive items as less positive. On the basis of present results, it is suggested that depressed subjects judged the emotional information with criteria different from normal individuals, and patients' emotional memory intensity is attenuated by their mood.

A steady state visually evoked potential investigation of memory and ageing.

PubMed

Macpherson, Helen; Pipingas, Andrew; Silberstein, Richard

2009-04-01

Old age is generally accompanied by a decline in memory performance. Specifically, neuroimaging and electrophysiological studies have revealed that there are age-related changes in the neural correlates of episodic and working memory. This study investigated age-associated changes in the steady state visually evoked potential (SSVEP) amplitude and latency associated with memory performance. Participants were 15 older (59-67 years) and 14 younger (20-30 years) adults who performed an object working memory (OWM) task and a contextual recognition memory (CRM) task, whilst the SSVEP was recorded from 64 electrode sites. Retention of a single object in the low demand OWM task was characterised by smaller frontal SSVEP amplitude and latency differences in older adults than in younger adults, indicative of an age-associated reduction in neural processes. Recognition of visual images in the more difficult CRM task was accompanied by larger, more sustained SSVEP amplitude and latency decreases over temporal parietal regions in older adults. In contrast, the more transient, frontally mediated pattern of activity demonstrated by younger adults suggests that younger and older adults utilize different neural resources to perform recognition judgements. The results provide support for compensatory processes in the aging brain; at lower task demands, older adults demonstrate reduced neural activity, whereas at greater task demands neural activity is increased.

Susceptibility to misleading information under social pressure in schizophrenia.

PubMed

Peters, Maarten J V; Moritz, Steffen; Tekin, Serra; Jelicic, Marko; Merckelbach, Harald

2012-11-01

Research looking at specific memory aberrations in the schizophrenia has primarily focused on their phenomenology using standardized semantic laboratory tasks. However, no study has investigated to what extent such aberrations have consequences for everyday episodic memories using more realistic false memory paradigms. Using a false memory paradigm where participants are presented with misleading suggestive information (Gudjonsson Suggestibility Scale), we investigated the susceptibility of patients with schizophrenia (n = 21) and healthy controls (n = 18) to post hoc misleading information acceptance and compliance. Patients with schizophrenia exhibited an increased susceptibility to go along with misleading suggestive items. Furthermore, they showed an increased tendency to change answers under conditions of social pressure. Underscoring previous findings on memory aberrations in schizophrenia, patients with schizophrenia had reduced levels of correct recognition (ie, true memory) relative to healthy controls. The effects remained stable when controlling for specific mediating variables such as symptom severity and intelligence in patients with schizophrenia. These findings are a first indication that social pressure and misleading information may impair source memory for everyday episodic memories in schizophrenia, and such impairment has clear consequences for treatment issues and forensic practice. Copyright © 2012 Elsevier Inc. All rights reserved.

Reversibility of object recognition but not spatial memory impairment following binge-like alcohol exposure in rats.

PubMed

Cippitelli, Andrea; Zook, Michelle; Bell, Lauren; Damadzic, Ruslan; Eskay, Robert L; Schwandt, Melanie; Heilig, Markus

2010-11-01

Excessive alcohol use leads to neurodegeneration in several brain structures including the hippocampal dentate gyrus and the entorhinal cortex. Cognitive deficits that result are among the most insidious and debilitating consequences of alcoholism. The object exploration task (OET) provides a sensitive measurement of spatial memory impairment induced by hippocampal and cortical damage. In this study, we examine whether the observed neurotoxicity produced by a 4-day binge ethanol treatment results in long-term memory impairment by observing the time course of reactions to spatial change (object configuration) and non-spatial change (object recognition). Wistar rats were assessed for their abilities to detect spatial configuration in the OET at 1 week and 10 weeks following the ethanol treatment, in which ethanol groups received 9-15 g/kg/day and achieved blood alcohol levels over 300 mg/dl. At 1 week, results indicated that the binge alcohol treatment produced impairment in both spatial memory and non-spatial object recognition performance. Unlike the controls, ethanol treated rats did not increase the duration or number of contacts with the displaced object in the spatial memory task, nor did they increase the duration of contacts with the novel object in the object recognition task. After 10 weeks, spatial memory remained impaired in the ethanol treated rats but object recognition ability was recovered. Our data suggest that episodes of binge-like alcohol exposure result in long-term and possibly permanent impairments in memory for the configuration of objects during exploration, whereas the ability to detect non-spatial changes is only temporarily affected. Copyright © 2010 Elsevier Inc. All rights reserved.

State orientation and memory load impair prospective memory performance in older compared to younger persons.

PubMed

Kaschel, Reiner; Kazén, Miguel; Kuhl, Julius

2017-07-01

A modified event-based paradigm of prospective memory was applied to investigate intention initiation in older and younger participants under high versus low memory load (subsequent episodic word recall vs. recognition). State versus action orientation, a personality dimension related to intention enactment, was also measured. State-oriented persons show a superiority effect for the storage of intentions in an explicit format but have a paradoxical deficit in their actual enactment. We predicted an interaction between aging, personality, and memory load, with longer intention-initiation latencies and higher omission rates for older state-oriented participants under high memory load. Results were consistent with predictions and are interpreted according to current personality and prospective memory models of aging.

Subchronic Glucocorticoid Receptor Inhibition Rescues Early Episodic Memory and Synaptic Plasticity Deficits in a Mouse Model of Alzheimer's Disease

PubMed Central

Lanté, Fabien; Chafai, Magda; Raymond, Elisabeth Fabienne; Salgueiro Pereira, Ana Rita; Mouska, Xavier; Kootar, Scherazad; Barik, Jacques; Bethus, Ingrid; Marie, Hélène

2015-01-01

The early phase of Alzheimer's disease (AD) is characterized by hippocampus-dependent memory deficits and impaired synaptic plasticity. Increasing evidence suggests that stress and dysregulation of the hypothalamo-pituitary-adrenal (HPA) axis, marked by the elevated circulating glucocorticoids, are risk factors for AD onset. How these changes contribute to early hippocampal dysfunction remains unclear. Using an elaborated version of the object recognition task, we carefully monitored alterations in key components of episodic memory, the first type of memory altered in AD patients, in early symptomatic Tg2576 AD mice. We also combined biochemical and ex vivo electrophysiological analyses to reveal novel cellular and molecular dysregulations underpinning the onset of the pathology. We show that HPA axis, circadian rhythm, and feedback mechanisms, as well as episodic memory, are compromised in this early symptomatic phase, reminiscent of human AD pathology. The cognitive decline could be rescued by subchronic in vivo treatment with RU486, a glucocorticoid receptor antagonist. These observed phenotypes were paralleled by a specific enhancement of N-Methyl-D-aspartic acid receptor (NMDAR)-dependent LTD in CA1 pyramidal neurons, whereas LTP and metabotropic glutamate receptor-dependent LTD remain unchanged. NMDAR transmission was also enhanced. Finally, we show that, as for the behavioral deficit, RU486 treatment rescues this abnormal synaptic phenotype. These preclinical results define glucocorticoid signaling as a contributing factor to both episodic memory loss and early synaptic failure in this AD mouse model, and suggest that glucocorticoid receptor targeting strategies could be beneficial to delay AD onset. PMID:25622751

Modulation of memory and visuospatial processes by biperiden and rivastigmine in elderly healthy subjects.

PubMed

Wezenberg, E; Verkes, R J; Sabbe, B G C; Ruigt, G S F; Hulstijn, W

2005-09-01

The central cholinergic system is implicated in cognitive functioning. The dysfunction of this system is expressed in many diseases like Alzheimer's disease, dementia of Lewy body, Parkinson's disease and vascular dementia. In recent animal studies, it was found that selective cholinergic modulation affects visuospatial processes even more than memory function. In the current study, we tried to replicate those findings. In order to investigate the acute effects of cholinergic drugs on memory and visuospatial functions, a selective anticholinergic drug, biperiden, was compared to a selective acetylcholinesterase-inhibiting drug, rivastigmine, in healthy elderly subjects. A double-blind, placebo-controlled, randomised, cross-over study was performed in 16 healthy, elderly volunteers (eight men, eight women; mean age 66.1, SD 4.46 years). All subjects received biperiden (2 mg), rivastigmine (3 mg) and placebo with an interval of 7 days between them. Testing took place 1 h after drug intake (which was around Tmax for both drugs). Subjects were presented with tests for episodic memory (wordlist and picture memory), working memory tasks (N-back, symbol recall) and motor learning (maze task, pursuit rotor). Visuospatial abilities were assessed by tests with high visual scanning components (tangled lines and Symbol Digit Substitution Test). Episodic memory was impaired by biperiden. Rivastigmine impaired recognition parts of the episodic memory performance. Working memory was non-significantly impaired by biperiden and not affected by rivastigmine. Motor learning as well as visuospatial processes were impaired by biperiden and improved by rivastigmine. These results implicate acetylcholine as a modulator not only of memory but also of visuospatial abilities.

Episodic effects on picture identification for alcoholic Korsakoff patients.

PubMed

Cermak, L S; Verfaellie, M; Letourneau, L; Jacoby, L L

1993-05-01

Experience with degraded pictures produces better subsequent identification of these pictures in amnesic patients. To examine the contribution of episodic memory to this facilitation, we compared identification of pictures that were identical to a studied picture, pictures that shared the same name with a studied picture, and new, unstudied pictures. In an initial phase of the experiment, patients clarified each picture until they could name it. During a second phase, they again clarified each picture and judged whether it was identical, similar (same-name), or different from pictures identified in the first phase. Korsakoff patients, as well as alcoholic controls, identified identical pictures faster than same-name pictures, and these in turn were identified faster than new pictures. The Korsakoff patients did show less facilitation than the alcoholic controls, but this difference was eliminated by testing the alcoholics after a week delay. The smaller facilitation in performance shown by amnesics and by alcoholics tested after a delay was accompanied by impaired recognition memory as well as by qualitative differences in recognition performance. The Korsakoff patients tended to label same-name pictures as different while alcoholic controls tested immediately called them identical, a tendency which disappeared when alcoholics were tested after a delay. These findings suggest that Korsakoff patients are influenced by specific episodic information even more than are alcoholic controls.

Adding Recognition Discriminability Index to the Delayed Recall Is Useful to Predict Conversion from Mild Cognitive Impairment to Alzheimer's Disease in the Alzheimer's Disease Neuroimaging Initiative.

PubMed

Russo, María J; Campos, Jorge; Vázquez, Silvia; Sevlever, Gustavo; Allegri, Ricardo F

2017-01-01

Background: Ongoing research is focusing on the identification of those individuals with mild cognitive impairment (MCI) who are most likely to convert to Alzheimer's disease (AD). We investigated whether recognition memory tasks in combination with delayed recall measure of episodic memory and CSF biomarkers can predict MCI to AD conversion at 24-month follow-up. Methods: A total of 397 amnestic-MCI subjects from Alzheimer's disease Neuroimaging Initiative were included. Logistic regression modeling was done to assess the predictive value of all RAVLT measures, risk factors such as age, sex, education, APOE genotype, and CSF biomarkers for progression to AD. Estimating adjusted odds ratios was used to determine which variables would produce an optimal predictive model, and whether adding tests of interaction between the RAVLT Delayed Recall and recognition measures (traditional score and d-prime) would improve prediction of the conversion from a-MCI to AD. Results: 112 (28.2%) subjects developed dementia and 285 (71.8%) subjects did not. Of the all included variables, CSF Aβ1-42 levels, RAVLT Delayed Recall, and the combination of RAVLT Delayed Recall and d-prime were predictive of progression to AD (χ 2 = 38.23, df = 14, p < 0.001). Conclusions: The combination of RAVLT Delayed Recall and d-prime measures may be predictor of conversion from MCI to AD in the ADNI cohort, especially in combination with amyloid biomarkers. A predictive model to help identify individuals at-risk for dementia should include not only traditional episodic memory measures (delayed recall or recognition), but also additional variables (d-prime) that allow the homogenization of the assessment procedures in the diagnosis of MCI.

Adding Recognition Discriminability Index to the Delayed Recall Is Useful to Predict Conversion from Mild Cognitive Impairment to Alzheimer's Disease in the Alzheimer's Disease Neuroimaging Initiative

PubMed Central

Russo, María J.; Campos, Jorge; Vázquez, Silvia; Sevlever, Gustavo; Allegri, Ricardo F.; Weiner, Michael W.

2017-01-01

Background: Ongoing research is focusing on the identification of those individuals with mild cognitive impairment (MCI) who are most likely to convert to Alzheimer's disease (AD). We investigated whether recognition memory tasks in combination with delayed recall measure of episodic memory and CSF biomarkers can predict MCI to AD conversion at 24-month follow-up. Methods: A total of 397 amnestic-MCI subjects from Alzheimer's disease Neuroimaging Initiative were included. Logistic regression modeling was done to assess the predictive value of all RAVLT measures, risk factors such as age, sex, education, APOE genotype, and CSF biomarkers for progression to AD. Estimating adjusted odds ratios was used to determine which variables would produce an optimal predictive model, and whether adding tests of interaction between the RAVLT Delayed Recall and recognition measures (traditional score and d-prime) would improve prediction of the conversion from a-MCI to AD. Results: 112 (28.2%) subjects developed dementia and 285 (71.8%) subjects did not. Of the all included variables, CSF Aβ1-42 levels, RAVLT Delayed Recall, and the combination of RAVLT Delayed Recall and d-prime were predictive of progression to AD (χ2 = 38.23, df = 14, p < 0.001). Conclusions: The combination of RAVLT Delayed Recall and d-prime measures may be predictor of conversion from MCI to AD in the ADNI cohort, especially in combination with amyloid biomarkers. A predictive model to help identify individuals at-risk for dementia should include not only traditional episodic memory measures (delayed recall or recognition), but also additional variables (d-prime) that allow the homogenization of the assessment procedures in the diagnosis of MCI. PMID:28344552

Interaction between episodic and semantic memory networks in the acquisition and consolidation of novel spoken words.

PubMed

Takashima, Atsuko; Bakker, Iske; van Hell, Janet G; Janzen, Gabriele; McQueen, James M

2017-04-01

When a novel word is learned, its memory representation is thought to undergo a process of consolidation and integration. In this study, we tested whether the neural representations of novel words change as a function of consolidation by observing brain activation patterns just after learning and again after a delay of one week. Words learned with meanings were remembered better than those learned without meanings. Both episodic (hippocampus-dependent) and semantic (dependent on distributed neocortical areas) memory systems were utilised during recognition of the novel words. The extent to which the two systems were involved changed as a function of time and the amount of associated information, with more involvement of both systems for the meaningful words than for the form-only words after the one-week delay. These results suggest that the reason the meaningful words were remembered better is that their retrieval can benefit more from these two complementary memory systems. Copyright © 2016 Elsevier Inc. All rights reserved.

The relational luring effect: Retrieval of relational information during associative recognition.

PubMed

Popov, Vencislav; Hristova, Penka; Anders, Royce

2017-05-01

Here we argue that semantic relations (e.g., works in: nurse-hospital) have abstract independent representations in long-term memory (LTM) and that the same representation is accessed by all exemplars of a specific relation. We present evidence from 2 associative recognition experiments that uncovered a novel relational luring effect (RLE) in recognition memory. Participants studied word pairs, and then discriminated between intact (old) pairs and recombined lures. In the first experiment participants responded more slowly to lures that were relationally similar (table-cloth) to studied pairs (floor-carpet), in contrast to relationally dissimilar lures (pipe-water). Experiment 2 extended the RLE by showing a continuous effect of relational lure strength on recognition times (RTs), false alarms, and hits. It used a continuous pair recognition task, where each recombined lure or target could be preceded by 0, 1, 2, 3 or 4 different exemplars of the same relation. RTs and false alarms increased linearly with the number of different previously seen relationally similar pairs. Moreover, more typical exemplars of a given relation lead to a stronger RLE. Finally, hits for intact pairs also rose with the number of previously studied different relational instances. These results suggest that semantic relations exist as independent representations in LTM and that during associative recognition these representations can be a spurious source of familiarity. We discuss the implications of the RLE for current models of semantic and episodic memory, unitization in associative recognition, analogical reasoning and retrieval, as well as constructive memory research. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Effect of semantic coherence on episodic memory processes in schizophrenia.

PubMed

Battal Merlet, Lâle; Morel, Shasha; Blanchet, Alain; Lockman, Hazlin; Kostova, Milena

2014-12-30

Schizophrenia is associated with severe episodic retrieval impairment. The aim of this study was to investigate the possibility that schizophrenia patients could improve their familiarity and/or recollection processes by manipulating the semantic coherence of to-be-learned stimuli and using deep encoding. Twelve schizophrenia patients and 12 healthy controls of comparable age, gender, and educational level undertook an associative recognition memory task. The stimuli consisted of pairs of words that were either related or unrelated to a given semantic category. The process dissociation procedure was used to calculate the estimates of familiarity and recollection processes. Both groups showed enhanced memory performances for semantically related words. However, in healthy controls, semantic relatedness led to enhanced recollection, while in schizophrenia patients, it induced enhanced familiarity. The familiarity estimates for related words were comparable in both groups, indicating that familiarity could be used as a compensatory mechanism in schizophrenia patients. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Short theta burst stimulation to left frontal cortex prior to encoding enhances subsequent recognition memory

PubMed Central

Demeter, Elise; Mirdamadi, Jasmine L.; Meehan, Sean K.; Taylor, Stephan F.

2016-01-01

Deep semantic encoding of verbal stimuli can aid in later successful retrieval of those stimuli from long-term episodic memory. Evidence from numerous neuropsychological and neuroimaging experiments demonstrate regions in left prefrontal cortex, including left dorsolateral prefrontal cortex (DLPFC), are important for processes related to encoding. Here, we investigated the relationship between left DLPFC activity during encoding and successful subsequent memory with transcranial magnetic stimulation (TMS). In a pair of experiments using a 2-session within-subjects design, we stimulated either left DLPFC or a control region (Vertex) with a single 2-s train of short theta burst stimulation (sTBS) during a semantic encoding task and then gave participants a recognition memory test. We found that subsequent memory was enhanced on the day left DLPFC was stimulated, relative to the day Vertex was stimulated, and that DLPFC stimulation also increased participants’ confidence in their decisions during the recognition task. We also explored the time course of how long the effects of sTBS persisted. Our data suggest 2 s of sTBS to left DLPFC is capable of enhancing subsequent memory for items encoded up to 15 s following stimulation. Collectively, these data demonstrate sTBS is capable of enhancing long-term memory and provide evidence that TBS protocols are a potentially powerful tool for modulating cognitive function. PMID:27098772

Confabulation versus experimentally induced false memories in Korsakoff patients.

PubMed

Van Damme, Ilse; d'Ydewalle, Géry

2010-09-01

The present study focuses on both the clinical symptom of confabulation and experimentally induced false memories in patients suffering from Korsakoff's syndrome. Despite the vast amount of case studies of confabulating patients and studies investigating false memories in the Deese-Roediger-McDermott (DRM) paradigm, the nature of Korsakoff patients' confabulatory behaviour and its association with DRM false memories have been rarely examined. Hence, the first aim of the present study was to evaluate confabulatory responses in a large sample of chronic Korsakoff patients and matched controls by means of the Dalla Barba Confabulation Battery. Second, the association between (provoked) confabulation and the patients' DRM false recognition performance was investigated. Korsakoff patients mainly confabulated in response to questions about episodic memory and questions to which the answer was unknown. A positive association was obtained between confabulation and the tendency to accept unstudied distractor words as being old in the DRM paradigm. On the other hand, there was a negative association between confabulation and false recognition of critical lures. The latter could be attributed to the importance of strategic retrieval at delayed memory testing.

Similar verbal memory impairments in schizophrenia and healthy aging. Implications for understanding of neural mechanisms.

PubMed

Silver, Henry; Bilker, Warren B

2015-03-30

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

Positive and negative emotional contexts unevenly predict episodic memory.

PubMed

Martínez-Galindo, Joyce Graciela; Cansino, Selene

2015-09-15

The aim of this study was to investigate whether the recognition of faces with neutral expressions differs when they are encoded under different emotional contexts (positive, negative or non-emotional). The effects of the emotional valence context on the subsequent memory effect (SME) and the autonomic responses were also examined. Twenty-eight participants performed a betting-game task in which the faces of their virtual opponents were presented in each trial. The probability of winning or losing was manipulated to generate positive or negative contexts, respectively. Additionally, the participants performed the same task without betting as a non-emotional condition. After the encoding phase, an old/new paradigm was performed for the faces of the virtual opponents. The recognition was superior for the faces encoded in the positive contexts than for the faces encoded in the non-emotional contexts. The skin conductance response amplitude was equivalent for both of the emotional contexts. The N170 and P300 components at occipital sites and the frontal slow wave manifested SMEs that were modulated by positive contexts; neither negative nor non-emotional contexts influenced these effects. The behavioral and neurophysiological data demonstrated that positive contexts are stronger predictors of episodic memory than negative or non-emotional contexts. Copyright © 2015 Elsevier B.V. All rights reserved.

Prevalence of impaired memory in hospitalized adults and associations with in-hospital sleep loss.

PubMed

Calev, Hila; Spampinato, Lisa M; Press, Valerie G; Meltzer, David O; Arora, Vineet M

2015-07-01

Effective inpatient teaching requires intact patient memory, but studies suggest hospitalized adults may have memory deficits. Sleep loss among inpatients could contribute to memory impairment. To assess memory in older hospitalized adults, and to test the association between sleep quantity, sleep quality, and memory, in order to identify a possible contributor to memory deficits in these patients. Prospective cohort study. General medicine and hematology/oncology inpatient wards. Fifty-nine hospitalized adults at least 50 years of age with no diagnosed sleep disorder. Immediate memory and memory after a 24-hour delay were assessed using a word recall and word recognition task from the University of Southern California Repeatable Episodic Memory Test. A vignette-based memory task was piloted as an alternative test more closely resembling discharge instructions. Sleep duration and efficiency overnight in the hospital were measured using actigraphy. Mean immediate recall was 3.8 words out of 15 (standard deviation = 2.1). Forty-nine percent of subjects had poor memory, defined as immediate recall score of 3 or lower. Median immediate recognition was 11 words out of 15 (interquartile range [IQR] = 9-13). Median delayed recall score was 1 word, and median delayed recognition was 10 words (IQR = 8-12). In-hospital sleep duration and efficiency were not significantly associated with memory. The medical vignette score was correlated with immediate recall (r = 0.49, P < 0.01). About half of the inpatients studied had poor memory while in the hospital, signaling that hospitalization might not be an ideal teachable moment. In-hospital sleep was not associated with memory scores. © 2015 Society of Hospital Medicine.

Prevalence of Impaired Memory in Hospitalized Adults and Associations with In-Hospital Sleep Loss

PubMed Central

Calev, Hila; Spampinato, Lisa M; Press, Valerie G; Meltzer, David O; Arora, Vineet M

2015-01-01

Background Effective inpatient teaching requires intact patient memory, but studies suggest hospitalized adults may have memory deficits. Sleep loss among inpatients could contribute to memory impairment. Objective To assess memory in older hospitalized adults, and to test the association between sleep quantity, sleep quality and memory, in order to identify a possible contributor to memory deficits in these patients. Design Prospective cohort study Setting General medicine and hematology/oncology inpatient wards Patients 59 hospitalized adults at least 50 years of age with no diagnosed sleep disorder. Measurements Immediate memory and memory after a 24-hour delay were assessed using a word recall and word recognition task from the University of Southern California Repeatable Episodic Memory Test (USC-REMT). A vignette-based memory task was piloted as an alternative test more closely resembling discharge instructions. Sleep duration and efficiency overnight in the hospital were measured using actigraphy. Results Mean immediate recall was 3.8 words out of 15 (SD=2.1). Forty-nine percent of subjects had poor memory, defined as immediate recall score of 3 or lower. Median immediate recognition was 11 words out of 15 (IQR=9, 13). Median delayed recall score was 1 word and median delayed recognition was 10 words (IQR= 8–12). In-hospital sleep duration and efficiency were not significantly associated with memory. The medical vignette score was correlated with immediate recall (r=0.49, p<0.01) Conclusions About half of inpatients studied had poor memory while in the hospital, signaling that hospitalization might not be an ideal teachable moment. In-hospital sleep was not associated with memory scores. PMID:25872763

Influence of emotional expression on memory recognition bias in schizophrenia as revealed by fMRI.

PubMed

Sergerie, Karine; Armony, Jorge L; Menear, Matthew; Sutton, Hazel; Lepage, Martin

2010-07-01

We recently showed that, in healthy individuals, emotional expression influences memory for faces both in terms of accuracy and, critically, in memory response bias (tendency to classify stimuli as previously seen or not, regardless of whether this was the case). Although schizophrenia has been shown to be associated with deficit in episodic memory and emotional processing, the relation between these processes in this population remains unclear. Here, we used our previously validated paradigm to directly investigate the modulation of emotion on memory recognition. Twenty patients with schizophrenia and matched healthy controls completed functional magnetic resonance imaging (fMRI) study of recognition memory of happy, sad, and neutral faces. Brain activity associated with the response bias was obtained by correlating this measure with the contrast subjective old (ie, hits and false alarms) minus subjective new (misses and correct rejections) for sad and happy expressions. Although patients exhibited an overall lower memory performance than controls, they showed the same effects of emotion on memory, both in terms of accuracy and bias. For sad faces, the similar behavioral pattern between groups was mirrored by a largely overlapping neural network, mostly involved in familiarity-based judgments (eg, parahippocampal gyrus). In contrast, controls activated a much larger set of regions for happy faces, including areas thought to underlie recollection-based memory retrieval (eg, superior frontal gyrus and hippocampus) and in novelty detection (eg, amygdala). This study demonstrates that, despite an overall lower memory accuracy, emotional memory is intact in schizophrenia, although emotion-specific differences in brain activation exist, possibly reflecting different strategies.

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

PubMed

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.

Hippocampal amnesia.

PubMed

Spiers, H J; Maguire, E A; Burgess, N

2001-01-01

This article reviews 147 cases of amnesia following damage including the hippocampus or fornix as reported in 179 publications. The aetiology, mnestic abilities and reference(s) are tabulated for each case. Consistent findings across cases include the association of bilateral hippocampal damage with a deficit in anterograde episodic memory combined with spared procedural and working memory. The limited nature of retrograde amnesia following lesions to the fornix is also noted. Less consistent and thus more controversial findings, include effects of lesion size or laterality, deficits in semantic memory or familiarity-based recognition and the extent of retrograde amnesia. The evidence concerning these issues is reviewed across cases.

Disambiguating past events: Accurate source memory for time and context depends on different retrieval processes.

PubMed

Persson, Bjorn M; Ainge, James A; O'Connor, Akira R

2016-07-01

Current animal models of episodic memory are usually based on demonstrating integrated memory for what happened, where it happened, and when an event took place. These models aim to capture the testable features of the definition of human episodic memory which stresses the temporal component of the memory as a unique piece of source information that allows us to disambiguate one memory from another. Recently though, it has been suggested that a more accurate model of human episodic memory would include contextual rather than temporal source information, as humans' memory for time is relatively poor. Here, two experiments were carried out investigating human memory for temporal and contextual source information, along with the underlying dual process retrieval processes, using an immersive virtual environment paired with a 'Remember-Know' memory task. Experiment 1 (n=28) showed that contextual information could only be retrieved accurately using recollection, while temporal information could be retrieved using either recollection or familiarity. Experiment 2 (n=24), which used a more difficult task, resulting in reduced item recognition rates and therefore less potential for contamination by ceiling effects, replicated the pattern of results from Experiment 1. Dual process theory predicts that it should only be possible to retrieve source context from an event using recollection, and our results are consistent with this prediction. That temporal information can be retrieved using familiarity alone suggests that it may be incorrect to view temporal context as analogous to other typically used source contexts. This latter finding supports the alternative proposal that time since presentation may simply be reflected in the strength of memory trace at retrieval - a measure ideally suited to trace strength interrogation using familiarity, as is typically conceptualised within the dual process framework. Copyright © 2016 Elsevier Inc. All rights reserved.

Sleep-dependent facilitation of episodic memory details.

PubMed

van der Helm, Els; Gujar, Ninad; Nishida, Masaki; Walker, Matthew P

2011-01-01

While a role for sleep in declarative memory processing is established, the qualitative nature of this consolidation benefit, and the physiological mechanisms mediating it, remain debated. Here, we investigate the impact of sleep physiology on characteristics of episodic memory using an item- (memory elements) and context- (contextual details associated with those elements) learning paradigm; the latter being especially dependent on the hippocampus. Following back-to-back encoding of two word lists, each associated with a different context, participants were assigned to either a Nap-group, who obtained a 120-min nap, or a No Nap-group. Six hours post-encoding, participants performed a recognition test involving item-memory and context-memory judgments. In contrast to item-memory, which demonstrated no between-group differences, a significant benefit in context-memory developed in the Nap-group, the extent of which correlated both with the amount of stage-2 NREM sleep and frontal fast sleep-spindles. Furthermore, a difference was observed on the basis of word-list order, with the sleep benefit and associated physiological correlations being selective for the second word-list, learned last (most proximal to sleep). These findings suggest that sleep may preferentially benefit contextual (hippocampal-dependent) aspects of memory, supported by sleep-spindle oscillations, and that the temporal order of initial learning differentially determines subsequent offline consolidation.

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

PubMed

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.

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

PubMed Central

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

Emotionally Negative Pictures Enhance Gist Memory

PubMed Central

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 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. PMID:27454002

Maintenance of youth-like processing protects against false memory in later adulthood.

PubMed

Fandakova, Yana; Lindenberger, Ulman; Shing, Yee Lee

2015-02-01

Normal cognitive aging compromises the ability to form and retrieve associations among features of a memory episode. One indicator of this age-related deficit is older adults' difficulty in detecting and correctly rejecting new associations of familiar items. Comparing 28 younger and 30 older adults on a continuous recognition task with word pairs, we found that older adults whose activation patterns deviate less from the average pattern of younger adults while detecting repaired associations show the following: (1) higher overall memory and fewer false recognitions; (2) stronger functional connectivity of prefrontal regions with middle temporal and parahippocampal gyrus; and (3) higher recall and strategic categorical clustering in an independently assessed free recall task. Deviations from the average young-adult network reflected underactivation of frontoparietal regions instead of overactivation of regions not activated by younger adults. We conclude that maintenance of youth-like task-relevant activation patterns is critical for preserving memory functions in later adulthood. Copyright © 2015 Elsevier Inc. All rights reserved.

Investigating the Functional Utility of the Left Parietal ERP Old/New Effect: Brain Activity Predicts within But Not between Participant Variance in Episodic Recollection.

PubMed

MacLeod, Catherine A; Donaldson, David I

2017-01-01

A success story within neuroimaging has been the discovery of distinct neural correlates of episodic retrieval, providing insight into the processes that support memory for past life events. Here we focus on one commonly reported neural correlate, the left parietal old/new effect, a positive going modulation seen in event-related potential (ERP) data that is widely considered to index episodic recollection. Substantial evidence links changes in the size of the left parietal effect to changes in remembering, but the precise functional utility of the effect remains unclear. Here, using forced choice recognition of verbal stimuli, we present a novel population level test of the hypothesis that the magnitude of the left parietal effect correlates with memory performance. We recorded ERPs during old/new recognition, source accuracy and Remember/Know/Guess tasks in two large samples of healthy young adults, and successfully replicated existing within participant modulations of the magnitude of the left parietal effect with recollection. Critically, however, both datasets also show that across participants the magnitude of the left parietal effect does not correlate with behavioral measures of memory - including both subjective and objective estimates of recollection. We conclude that in these tasks, and across this healthy young adult population, the generators of the left parietal ERP effect do not index performance as expected. Taken together, these novel findings provide important constraints on the functional interpretation of the left parietal effect, suggesting that between group differences in the magnitude of old/new effects cannot always safely be used to infer differences in recollection.

False memories in highly superior autobiographical memory individuals

PubMed Central

Patihis, Lawrence; Frenda, Steven J.; LePort, Aurora K. R.; Petersen, Nicole; Nichols, Rebecca M.; Stark, Craig E. L.; McGaugh, James L.; Loftus, Elizabeth F.

2013-01-01

The recent identification of highly superior autobiographical memory (HSAM) raised the possibility that there may be individuals who are immune to memory distortions. We measured HSAM participants’ and age- and sex-matched controls’ susceptibility to false memories using several research paradigms. HSAM participants and controls were both susceptible to false recognition of nonpresented critical lure words in an associative word-list task. In a misinformation task, HSAM participants showed higher overall false memory compared with that of controls for details in a photographic slideshow. HSAM participants were equally as likely as controls to mistakenly report they had seen nonexistent footage of a plane crash. Finding false memories in a superior-memory group suggests that malleable reconstructive mechanisms may be fundamental to episodic remembering. Paradoxically, HSAM individuals may retrieve abundant and accurate autobiographical memories using fallible reconstructive processes. PMID:24248358

Directed forgetting of complex pictures in an item method paradigm.

PubMed

Hauswald, Anne; Kissler, Johanna

2008-11-01

An item-cued directed forgetting paradigm was used to investigate the ability to control episodic memory and selectively encode complex coloured pictures. A series of photographs was presented to 21 participants who were instructed to either remember or forget each picture after it was presented. Memory performance was later tested with a recognition task where all presented items had to be retrieved, regardless of the initial instructions. A directed forgetting effect--that is, better recognition of "to-be-remembered" than of "to-be-forgotten" pictures--was observed, although its size was smaller than previously reported for words or line drawings. The magnitude of the directed forgetting effect correlated negatively with participants' depression and dissociation scores. The results indicate that, at least in an item method, directed forgetting occurs for complex pictures as well as words and simple line drawings. Furthermore, people with higher levels of dissociative or depressive symptoms exhibit altered memory encoding patterns.

Using virtual reality to characterize episodic memory profiles in amnestic mild cognitive impairment and Alzheimer's disease: influence of active and passive encoding.

PubMed

Plancher, G; Tirard, A; Gyselinck, V; Nicolas, S; Piolino, P

2012-04-01

Most neuropsychological assessments of episodic memory bear little similarity to the events that patients actually experience as memories in daily life. The first aim of this study was to use a virtual environment to characterize episodic memory profiles in an ecological fashion, which includes memory for central and perceptual details, spatiotemporal contextual elements, and binding. This study included subjects from three different populations: healthy older adults, patients with amnestic mild cognitive impairment (aMCI) and patients with early to moderate Alzheimer's disease (AD). Second, we sought to determine whether environmental factors that can affect encoding (active vs. passive exploration) influence memory performance in pathological aging. Third, we benchmarked the results of our virtual reality episodic memory test against a classical memory test and a subjective daily memory complaint scale. Here, the participants were successively immersed in two virtual environments; the first, as the driver of a virtual car (active exploration) and the second, as the passenger of that car (passive exploration). Subjects were instructed to encode all elements of the environment as well as the associated spatiotemporal contexts. Following each immersion, we assessed the patient's recall and recognition of central information (i.e., the elements of the environment), contextual information (i.e., temporal, egocentric and allocentric spatial information) and lastly, the quality of binding. We found that the AD patients' performances were inferior to that of the aMCI and even more to that of the healthy aged groups, in line with the progression of hippocampal atrophy reported in the literature. Spatial allocentric memory assessments were found to be particularly useful for distinguishing aMCI patients from healthy older adults. Active exploration yielded enhanced recall of central and allocentric spatial information, as well as binding in all groups. This led aMCI patients to achieve better performance scores on immediate temporal memory tasks. Finally, the patients' daily memory complaints were more highly correlated with the performances on the virtual test than with their performances on the classical memory test. Taken together, these results highlight specific cognitive differences found between these three populations that may provide additional insight into the early diagnosis and rehabilitation of pathological aging. In particular, neuropsychological studies would benefit to use virtual tests and a multi-component approach to assess episodic memory, and encourage active encoding of information in patients suffering from mild or severe age-related memory impairment. The beneficial effect of active encoding on episodic memory in aMCI and early to moderate AD is discussed in the context of relatively preserved frontal and motor brain functions implicated in self-referential effects and procedural abilities. Copyright © 2011 Elsevier Ltd. All rights reserved.

Transcranial magnetic stimulation of the left angular gyrus during encoding does not impair associative memory performance.

PubMed

Koen, Joshua D; Thakral, Preston P; Rugg, Michael D

2018-06-05

The left angular gyrus (AG) is thought to play a critical role in episodic retrieval and has been implicated in the recollection of specific details of prior episodes. Motivated by recent fMRI studies in which it was reported that elevated neural activity in left AG during study is predictive of subsequent associative memory, the present study investigated whether the region plays a causal role in associative memory encoding. Participants underwent online transcranial magnetic stimulation (TMS) while encoding word pairs prior to an associative memory test. We predicted that TMS to left AG during encoding would result in reduced subsequent memory accuracy, especially for estimates of recollection. The results did not support this prediction: estimates of both recollection and familiarity-driven recognition were essentially identical for words pairs encoded during TMS to left AG relative to a vertex control site. These results suggest that the left AG may not play a necessary role in associative memory encoding. TMS to left AG did however affect confidence for incorrect 'intact' judgments to rearranged pairs and incorrect 'rearranged' judgments to intact pairs. These findings suggest that the left AG supports encoding processes that contribute to aspects of subjective mnemonic experience.

Event-related brain potential correlates of two states of conscious awareness in memory

PubMed Central

Düzel, Emrah; Yonelinas, Andrew P.; Mangun, George R.; Heinze, Hans-Jochen; Tulving, Endel

1997-01-01

We report an event-related potential (ERP) experiment of human recognition memory that explored the relation between conscious awareness and electrophysiological activity of the brain. We recorded ERPs from healthy adults while they made “remember” and “know” recognition judgments about previously seen words. These two kinds of judgments reflect “autonoetic” and “noetic” awareness, respectively. The ERP effects differed between the two kinds of awareness while they were similar for “true” and “false” recognition. Noetic awareness was associated with a temporoparietal positivity in the N400 range (325–600 ms) and a late (600–1,000 ms) frontocentral negativity, whereas autonoetic awareness was associated with a widespread, late, bifrontal and left parietotemporal (600–1000 ms) positivity. In the very late (1,300–1,900 ms) time window, a right frontal positivity was observed for both remember and know judgments of both true and false targets. These results provide physiological evidence for two types of conscious awareness in episodic memory retrieval. PMID:9159185

A Four–Component Model of Age–Related Memory Change

PubMed Central

Healey, M. Karl; Kahana, Michael J.

2015-01-01

We develop a novel, computationally explicit, theory of age–related memory change within the framework of the context maintenance and retrieval (CMR2) model of memory search. We introduce a set of benchmark findings from the free recall and recognition tasks that includes aspects of memory performance that show both age-related stability and decline. We test aging theories by lesioning the corresponding mechanisms in a model fit to younger adult free recall data. When effects are considered in isolation, many theories provide an adequate account, but when all effects are considered simultaneously, the existing theories fail. We develop a novel theory by fitting the full model (i.e., allowing all parameters to vary) to individual participants and comparing the distributions of parameter values for older and younger adults. This theory implicates four components: 1) the ability to sustain attention across an encoding episode, 2) the ability to retrieve contextual representations for use as retrieval cues, 3) the ability to monitor retrievals and reject intrusions, and 4) the level of noise in retrieval competitions. We extend CMR2 to simulate a recognition memory task using the same mechanisms the free recall model uses to reject intrusions. Without fitting any additional parameters, the four–component theory that accounts for age differences in free recall predicts the magnitude of age differences in recognition memory accuracy. Confirming a prediction of the model, free recall intrusion rates correlate positively with recognition false alarm rates. Thus we provide a four–component theory of a complex pattern of age differences across two key laboratory tasks. PMID:26501233

Examining Event-Related Potential (ERP) Correlates of Decision Bias in Recognition Memory Judgments

PubMed Central

Hill, Holger; Windmann, Sabine

2014-01-01

Memory judgments can be based on accurate memory information or on decision bias (the tendency to report that an event is part of episodic memory when one is in fact unsure). Event related potentials (ERP) correlates are important research tools for elucidating the dynamics underlying memory judgments but so far have been established only for investigations of accurate old/new discrimination. To identify the ERP correlates of bias, and observe how these interact with ERP correlates of memory, we conducted three experiments that manipulated decision bias within participants via instructions during recognition memory tests while their ERPs were recorded. In Experiment 1, the bias manipulation was performed between blocks of trials (automatized bias) and compared to trial-by-trial shifts of bias in accord with an external cue (flexibly controlled bias). In Experiment 2, the bias manipulation was performed at two different levels of accurate old/new discrimination as the memory strength of old (studied) items was varied. In Experiment 3, the bias manipulation was added to another, bottom-up driven manipulation of bias induced via familiarity. In the first two Experiments, and in the low familiarity condition of Experiment 3, we found evidence of an early frontocentral ERP component at 320 ms poststimulus (the FN320) that was sensitive to the manipulation of bias via instruction, with more negative amplitudes indexing more liberal bias. By contrast, later during the trial (500–700 ms poststimulus), bias effects interacted with old/new effects across all three experiments. Results suggest that the decision criterion is typically activated early during recognition memory trials, and is integrated with retrieved memory signals and task-specific processing demands later during the trial. More generally, the findings demonstrate how ERPs can help to specify the dynamics of recognition memory processes under top-down and bottom-up controlled retrieval conditions. PMID:25264982

Examining Event-Related Potential (ERP) correlates of decision bias in recognition memory judgments.

PubMed

Hill, Holger; Windmann, Sabine

2014-01-01

Memory judgments can be based on accurate memory information or on decision bias (the tendency to report that an event is part of episodic memory when one is in fact unsure). Event related potentials (ERP) correlates are important research tools for elucidating the dynamics underlying memory judgments but so far have been established only for investigations of accurate old/new discrimination. To identify the ERP correlates of bias, and observe how these interact with ERP correlates of memory, we conducted three experiments that manipulated decision bias within participants via instructions during recognition memory tests while their ERPs were recorded. In Experiment 1, the bias manipulation was performed between blocks of trials (automatized bias) and compared to trial-by-trial shifts of bias in accord with an external cue (flexibly controlled bias). In Experiment 2, the bias manipulation was performed at two different levels of accurate old/new discrimination as the memory strength of old (studied) items was varied. In Experiment 3, the bias manipulation was added to another, bottom-up driven manipulation of bias induced via familiarity. In the first two Experiments, and in the low familiarity condition of Experiment 3, we found evidence of an early frontocentral ERP component at 320 ms poststimulus (the FN320) that was sensitive to the manipulation of bias via instruction, with more negative amplitudes indexing more liberal bias. By contrast, later during the trial (500-700 ms poststimulus), bias effects interacted with old/new effects across all three experiments. Results suggest that the decision criterion is typically activated early during recognition memory trials, and is integrated with retrieved memory signals and task-specific processing demands later during the trial. More generally, the findings demonstrate how ERPs can help to specify the dynamics of recognition memory processes under top-down and bottom-up controlled retrieval conditions.

Differential effects of acute cortisol administration on deep and shallow episodic memory traces: a study on healthy males.

PubMed

Cioncoloni, David; Galli, Giulia; Mazzocchio, Riccardo; Feurra, Matteo; Giovannelli, Fabio; Santarnecchi, Emiliano; Bonifazi, Marco; Rossi, Alessandro; Rossi, Simone

2014-10-01

We aimed at investigating rapid effects of plasma cortisol elevations on the episodic memory phase of encoding or retrieval, and on the strength of the memory trace. Participants were asked either to select a word containing the letter "e" (shallow encoding task) or to judge if a word referred to a living entity (deep encoding task). We intravenously administered a bolus of 20mg of cortisol either 5 min before encoding or 5 min before retrieval, in a between-subjects design. The study included only male participants tested in the late afternoon, and neutral words as stimuli. When cortisol administration occurred prior to retrieval, a main effect of group emerged. Recognition accuracy was higher for individuals who received cortisol compared to placebo. The higher discrimination accuracy for the cortisol group was significant for words encoded during deep but not shallow task. Cortisol administration before encoding did not affect subsequent retrieval performance (either for deep or shallow stimuli) despite a facilitatory trend. Because genomic mechanisms take some time to develop, such a mechanism cannot apply to our findings where the memory task was performed shortly after the enhancement of glucocorticoid levels. Therefore, glucocorticoids, through non-genomic fast effects, determine an enhancement in episodic memory if administered immediately prior to retrieval. This effect is more evident if the memory trace is laid down through deep encoding operations involving the recruitment of specific neural networks. Copyright © 2014 Elsevier Inc. All rights reserved.

Classic and recent advances in understanding amnesia.

PubMed

Allen, Richard J

2018-01-01

Neurological amnesia has been and remains the focus of intense study, motivated by the drive to understand typical and atypical memory function and the underlying brain basis that is involved. There is now a consensus that amnesia associated with hippocampal (and, in many cases, broader medial temporal lobe) damage results in deficits in episodic memory, delayed recall, and recollective experience. However, debate continues regarding the patterns of preservation and impairment across a range of abilities, including semantic memory and learning, delayed recognition, working memory, and imagination. This brief review highlights some of the influential and recent advances in these debates and what they may tell us about the amnesic condition and hippocampal function.

Pushing Typists Back on the Learning Curve: Memory Chunking Improves Retrieval of Prior Typing Episodes

ERIC Educational Resources Information Center

Yamaguchi, Motonori; Randle, James M.; Wilson, Thomas L.; Logan, Gordon D.

2017-01-01

Hierarchical control of skilled performance depends on chunking of several lower-level units into a single higher-level unit. The present study examined the relationship between chunking and recognition of trained materials in the context of typewriting. In 3 experiments, participants were trained with typing nonwords and were later tested on…

Characterizing age-related decline of recognition memory and brain activation profile in mice.

PubMed

Belblidia, Hassina; Leger, Marianne; Abdelmalek, Abdelouadoud; Quiedeville, Anne; Calocer, Floriane; Boulouard, Michel; Jozet-Alves, Christelle; Freret, Thomas; Schumann-Bard, Pascale

2018-06-01

Episodic memory decline is one of the earlier deficits occurring during normal aging in humans. The question of spatial versus non-spatial sensitivity to age-related memory decline is of importance for a full understanding of these changes. Here, we characterized the effect of normal aging on both non-spatial (object) and spatial (object location) memory performances as well as on associated neuronal activation in mice. Novel-object (NOR) and object-location (OLR) recognition tests, respectively assessing the identity and spatial features of object memory, were examined at different ages. We show that memory performances in both tests were altered by aging as early as 15 months of age: NOR memory was partially impaired whereas OLR memory was found to be fully disrupted at 15 months of age. Brain activation profiles were assessed for both tests using immunohistochemical detection of c-Fos (neuronal activation marker) in 3and 15 month-old mice. Normal performances in NOR task by 3 month-old mice were associated to an activation of the hippocampus and a trend towards an activation in the perirhinal cortex, in a way that did significantly differ with 15 month-old mice. During OLR task, brain activation took place in the hippocampus in 3 month-old but not significantly in 15 month-old mice, which were fully impaired at this task. These differential alterations of the object- and object-location recognition memory may be linked to differential alteration of the neuronal networks supporting these tasks. Copyright © 2018 Elsevier Inc. All rights reserved.

"Disorganized in time": impact of bottom-up and top-down negative emotion generation on memory formation among healthy and traumatized adolescents.

PubMed

Guillery-Girard, Bérengère; Clochon, Patrice; Giffard, Bénédicte; Viard, Armelle; Egler, Pierre-Jean; Baleyte, Jean-Marc; Eustache, Francis; Dayan, Jacques

2013-09-01

"Travelling in time," a central feature of episodic memory is severely affected among individuals with Post Traumatic Stress Disorder (PTSD) with two opposite effects: vivid traumatic memories are unorganized in temporality (bottom-up processes), non-traumatic personal memories tend to lack spatio-temporal details and false recognitions occur more frequently that in the general population (top-down processes). To test the effect of these two types of processes (i.e. bottom-up and top-down) on emotional memory, we conducted two studies in healthy and traumatized adolescents, a period of life in which vulnerability to emotion is particularly high. Using negative and neutral images selected from the international affective picture system (IAPS), stimuli were divided into perceptual images (emotion generated by perceptual details) and conceptual images (emotion generated by the general meaning of the material). Both categories of stimuli were then used, along with neutral pictures, in a memory task with two phases (encoding and recognition). In both populations, we reported a differential effect of the emotional material on encoding and recognition. Negative perceptual scenes induced an attentional capture effect during encoding and enhanced the recollective distinctiveness. Conversely, the encoding of conceptual scenes was similar to neutral ones, but the conceptual relatedness induced false memories at retrieval. However, among individuals with PTSD, two subgroups of patients were identified. The first subgroup processed the scenes faster than controls, except for the perceptual scenes, and obtained similar performances to controls in the recognition task. The second subgroup group desmonstrated an attentional deficit in the encoding task with no benefit from the distinctiveness associated with negative perceptual scenes on memory performances. These findings provide a new perspective on how negative emotional information may have opposite influences on memory in normal and traumatized individuals. It also gives clues to understand how intrusive memories and overgeneralization takes place in PTSD. Copyright © 2013 Elsevier Ltd. All rights reserved.

Emotionally negative pictures enhance gist memory.

PubMed

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).

A single-trace dual-process model of episodic memory: a novel computational account of familiarity and recollection.

PubMed

Greve, Andrea; Donaldson, David I; van Rossum, Mark C W

2010-02-01

Dual-process theories of episodic memory state that retrieval is contingent on two independent processes: familiarity (providing a sense of oldness) and recollection (recovering events and their context). A variety of studies have reported distinct neural signatures for familiarity and recollection, supporting dual-process theory. One outstanding question is whether these signatures reflect the activation of distinct memory traces or the operation of different retrieval mechanisms on a single memory trace. We present a computational model that uses a single neuronal network to store memory traces, but two distinct and independent retrieval processes access the memory. The model is capable of performing familiarity and recollection-based discrimination between old and new patterns, demonstrating that dual-process models need not to rely on multiple independent memory traces, but can use a single trace. Importantly, our putative familiarity and recollection processes exhibit distinct characteristics analogous to those found in empirical data; they diverge in capacity and sensitivity to sparse and correlated patterns, exhibit distinct ROC curves, and account for performance on both item and associative recognition tests. The demonstration that a single-trace, dual-process model can account for a range of empirical findings highlights the importance of distinguishing between neuronal processes and the neuronal representations on which they operate.

Sleep reduces false memory in healthy older adults.

PubMed

Lo, June C; Sim, Sam K Y; Chee, Michael W L

2014-04-01

To investigate the effects of post-learning sleep and sleep architecture on false memory in healthy older adults. Balanced, crossover design. False memory was induced using the Deese-Roediger-McDermott (DRM) paradigm and assessed following nocturnal sleep and following a period of daytime wakefulness. Post-learning sleep structure was evaluated using polysomnography (PSG). Sleep research laboratory. Fourteen healthy older adults from the Singapore-Longitudinal Aging Brain Study (mean age ± standard deviation = 66.6 ± 4.1 y; 7 males). At encoding, participants studied lists of words that were semantically related to non-presented critical lures. At retrieval, they made "remember"/"know" and "new" judgments. Compared to wakefulness, post-learning sleep was associated with reduced "remember" responses, but not "know" responses to critical lures. In contrast, there were no significant differences in the veridical recognition of studied words, false recognition of unrelated distractors, discriminability, or response bias between the sleep and the wake conditions. More post-learning slow wave sleep was associated with greater reduction in false memory. In healthy older adults, sleep facilitates the reduction in false memory without affecting veridical memory. This benefit correlates with the amount of slow wave sleep in the post-learning sleep episode.

Age-related individual variability in memory performance is associated with amygdala-hippocampal circuit function and emotional pattern separation.

PubMed

Leal, Stephanie L; Noche, Jessica A; Murray, Elizabeth A; Yassa, Michael A

2017-01-01

While aging is generally associated with episodic memory decline, not all older adults exhibit memory loss. Furthermore, emotional memories are not subject to the same extent of forgetting and appear preserved in aging. We conducted high-resolution fMRI during a task involving pattern separation of emotional information in older adults with and without age-related memory impairment (characterized by performance on a word-list learning task: low performers: LP vs. high performers: HP). We found signals consistent with emotional pattern separation in hippocampal dentate (DG)/CA3 in HP but not in LP individuals, suggesting a deficit in emotional pattern separation. During false recognition, we found increased DG/CA3 activity in LP individuals, suggesting that hyperactivity may be associated with overgeneralization. We additionally observed a selective deficit in basolateral amygdala-lateral entorhinal cortex-DG/CA3 functional connectivity in LP individuals during pattern separation of negative information. During negative false recognition, LP individuals showed increased medial temporal lobe functional connectivity, consistent with overgeneralization. Overall, these results suggest a novel mechanistic account of individual differences in emotional memory alterations exhibited in aging. Copyright © 2016 Elsevier Inc. All rights reserved.

Age-related individual variability in memory performance is associated with amygdala-hippocampal circuit function and emotional pattern separation

PubMed Central

Leal, Stephanie L.; Noche, Jessica A.; Murray, Elizabeth A.; Yassa, Michael A.

2018-01-01

While aging is generally associated with episodic memory decline, not all older adults exhibit memory loss. Furthermore, emotional memories are not subject to the same extent of forgetting and appear preserved in aging. We conducted high-resolution fMRI during a task involving pattern separation of emotional information in older adults with and without age-related memory impairment (characterized by performance on a word-list learning task: low performers: LP vs. high performers: HP). We found signals consistent with emotional pattern separation in hippocampal dentate (DG)/CA3 in HP but not in LP individuals, suggesting a deficit in emotional pattern separation. During false recognition, we found increased DG/CA3 activity in LP individuals, suggesting that hyperactivity may be associated with overgeneralization. We additionally observed a selective deficit in basolateral amygdala—lateral entorhinal cortex—DG/CA3 functional connectivity in LP individuals during pattern separation of negative information. During negative false recognition, LP individuals showed increased medial temporal lobe functional connectivity, consistent with overgeneralization. Overall, these results suggest a novel mechanistic account of individual differences in emotional memory alterations exhibited in aging. PMID:27723500

Memory for Self-Performed Actions in Individuals with Asperger Syndrome

PubMed Central

Zalla, Tiziana; Daprati, Elena; Sav, Anca-Maria; Chaste, Pauline; Nico, Daniele; Leboyer, Marion

2010-01-01

Memory for action is enhanced if individuals are allowed to perform the corresponding movements, compared to when they simply listen to them (enactment effect). Previous studies have shown that individuals with Autism Spectrum Disorders (ASD) have difficulties with processes involving the self, such as autobiographical memories and self performed actions. The present study aimed at assessing memory for action in Asperger Syndrome (AS). We investigated whether adults with AS would benefit from the enactment effect when recalling a list of previously performed items vs. items that were only visually and verbally experienced through three experimental tasks (Free Recall, Old/New Recognition and Source Memory). The results showed that while performance on Recognition and Source Memory tasks was preserved in individuals with AS, the enactment effect for self-performed actions was not consistently present, as revealed by the lower number of performed actions being recalled on the Free Recall test, as compared to adults with typical development. Subtle difficulties in encoding specific motor and proprioceptive signals during action execution in individuals with AS might affect retrieval of relevant personal episodic information. These disturbances might be associated to an impaired action monitoring system. PMID:20967277

Memory for self-performed actions in individuals with Asperger syndrome.

PubMed

Zalla, Tiziana; Daprati, Elena; Sav, Anca-Maria; Chaste, Pauline; Nico, Daniele; Leboyer, Marion

2010-10-12

Memory for action is enhanced if individuals are allowed to perform the corresponding movements, compared to when they simply listen to them (enactment effect). Previous studies have shown that individuals with Autism Spectrum Disorders (ASD) have difficulties with processes involving the self, such as autobiographical memories and self performed actions. The present study aimed at assessing memory for action in Asperger Syndrome (AS). We investigated whether adults with AS would benefit from the enactment effect when recalling a list of previously performed items vs. items that were only visually and verbally experienced through three experimental tasks (Free Recall, Old/New Recognition and Source Memory). The results showed that while performance on Recognition and Source Memory tasks was preserved in individuals with AS, the enactment effect for self-performed actions was not consistently present, as revealed by the lower number of performed actions being recalled on the Free Recall test, as compared to adults with typical development. Subtle difficulties in encoding specific motor and proprioceptive signals during action execution in individuals with AS might affect retrieval of relevant personal episodic information. These disturbances might be associated to an impaired action monitoring system.

A role for CA3 in social recognition memory.

PubMed

Chiang, Ming-Ching; Huang, Arthur J Y; Wintzer, Marie E; Ohshima, Toshio; McHugh, Thomas J

2018-02-02

Social recognition memory is crucial for survival across species, underlying the need to correctly identify conspecifics, mates and potential enemies. In humans the hippocampus is engaged in social and episodic memory, however the circuit mechanisms of social memory in rodent models has only recently come under scrutiny. Work in mice has established that the dorsal CA2 and ventral CA1 regions play critical roles, however a more comprehensive comparative analyses of the circuits and mechanisms required has not been reported. Here we employ conditional genetics to examine the differential contributions of the hippocampal subfields to social memory. We find that the deletion of NMDA receptor subunit 1 gene (NR1), which abolishes NMDA receptor synaptic plasticity, in CA3 pyramidal cells led to deficits in social memory; however, mice lacking the same gene in DG granule cells performed indistinguishable from controls. Further, we use conditional pharmacogenetic inhibition to demonstrate that activity in ventral, but not dorsal, CA3 is necessary for the encoding of a social memory. These findings demonstrated CA3 pyramidal cell plasticity and transmission contribute to the encoding of social stimuli and help further identify the distinct circuits underlying the role of the hippocampus in social memory. Copyright © 2018 Elsevier B.V. All rights reserved.

Environmental impoverishment and aging alter object recognition, spatial learning, and dentate gyrus astrocytes.

PubMed

Diniz, Daniel G; Foro, César A R; Rego, Carla M D; Gloria, David A; de Oliveira, Fabio R R; Paes, Juliana M P; de Sousa, Aline A; Tokuhashi, Tatyana P; Trindade, Lucas S; Turiel, Maíra C P; Vasconcelos, Erick G R; Torres, João B; Cunnigham, Colm; Perry, Victor H; Vasconcelos, Pedro F da Costa; Diniz, Cristovam W P

2010-08-01

Environmental and age-related effects on learning and memory were analysed and compared with changes observed in astrocyte laminar distribution in the dentate gyrus. Aged (20 months) and young (6 months) adult female albino Swiss mice were housed from weaning either in impoverished conditions or in enriched conditions, and tested for episodic-like and water maze spatial memories. After these behavioral tests, brain hippocampal sections were immunolabeled for glial fibrillary acid protein to identify astrocytes. The effects of environmental enrichment on episodic-like memory were not dependent on age, and may protect water maze spatial learning and memory from declines induced by aging or impoverished environment. In the dentate gyrus, the number of astrocytes increased with both aging and enriched environment in the molecular layer, increased only with aging in the polymorphic layer, and was unchanged in the granular layer. We suggest that long-term experience-induced glial plasticity by enriched environment may represent at least part of the circuitry groundwork for improvements in behavioral performance in the aged mice brain.

How "implicit" are implicit color effects in memory?

PubMed

Zimmer, Hubert D; Steiner, Astrid; Ecker, Ullrich K H

2002-01-01

Processing colored pictures of objects results in a preference to choose the former color for a specific object in a subsequent color choice test (Wippich & Mecklenbräuker, 1998). We tested whether this implicit memory effect is independent of performances in episodic color recollection (recognition). In the study phase of Experiment 1, the color of line drawings was either named or its appropriateness was judged. We found only weak implicit memory effects for categorical color information. In Experiment 2, silhouettes were colored by subjects during the study phase. Performances in both the implicit and the explicit test were good. Selections of "old" colors in the implicit test, though, were almost completely confined to items for which the color was also remembered explicitly. In Experiment 3, we applied the opposition technique in order to check whether we could find any implicit effects regarding items for which no explicit color recollection was possible. This was not the case. We therefore draw the conclusion that implicit color preference effects are not independent of explicit recollection, and that they are probably based on the same episodic memory traces that are used in explicit tests.

Psychoactive drugs and false memory: comparison of dextroamphetamine and delta-9-tetrahydrocannabinol on false recognition

PubMed Central

Ballard, Michael E.; Gallo, David A.; de Wit, Harriet

2014-01-01

Rationale Several psychoactive drugs are known to influence episodic memory. However, these drugs’ effects on false memory, or the tendency to incorrectly remember nonstudied information, remain poorly understood. Objectives Here, we examined the effects of two commonly used psychoactive drugs, one with memory-enhancing properties (dextroamphetamine; AMP), and another with memory-impairing properties (Δ9-tetrahydrocannabinol; THC), on false memory using the Deese/Roediger–McDermott (DRM) illusion. Methods Two parallel studies were conducted in which healthy volunteers received either AMP (0, 10, and 20 mg) or THC (0, 7.5, and 15 mg) in within-subjects, randomized, double-blind designs. Participants studied DRM word lists under the influence of the drugs, and their recognition memory for the studied words was tested 2 days later, under sober conditions. Results As expected, AMP increased memory of studied words relative to placebo, and THC reduced memory of studied words. Although neither drug significantly affected false memory relative to placebo, AMP increased false memory relative to THC. Across participants, both drugs’ effects on true memory were positively correlated with their effects on false memory. Conclusions Our results indicate that AMP and THC have opposing effects on true memory, and these effects appear to correspond to similar, albeit more subtle, effects on false memory. These findings are consistent with previous research using the DRM illusion and provide further evidence that psychoactive drugs can affect the encoding processes that ultimately result in the creation of false memories. PMID:21647577

Psychoactive drugs and false memory: comparison of dextroamphetamine and δ-9-tetrahydrocannabinol on false recognition.

PubMed

Ballard, Michael E; Gallo, David A; de Wit, Harriet

2012-01-01

Several psychoactive drugs are known to influence episodic memory. However, these drugs' effects on false memory, or the tendency to incorrectly remember nonstudied information, remain poorly understood. Here, we examined the effects of two commonly used psychoactive drugs, one with memory-enhancing properties (dextroamphetamine; AMP), and another with memory-impairing properties (Δ(9)-tetrahydrocannabinol; THC), on false memory using the Deese/Roediger-McDermott (DRM) illusion. Two parallel studies were conducted in which healthy volunteers received either AMP (0, 10, and 20 mg) or THC (0, 7.5, and 15 mg) in within-subjects, randomized, double-blind designs. Participants studied DRM word lists under the influence of the drugs, and their recognition memory for the studied words was tested 2 days later, under sober conditions. As expected, AMP increased memory of studied words relative to placebo, and THC reduced memory of studied words. Although neither drug significantly affected false memory relative to placebo, AMP increased false memory relative to THC. Across participants, both drugs' effects on true memory were positively correlated with their effects on false memory. Our results indicate that AMP and THC have opposing effects on true memory, and these effects appear to correspond to similar, albeit more subtle, effects on false memory. These findings are consistent with previous research using the DRM illusion and provide further evidence that psychoactive drugs can affect the encoding processes that ultimately result in the creation of false memories.

Remote semantic memory for public figures in HIV infection, alcoholism, and their comorbidity.

PubMed

Fama, Rosemary; Rosenbloom, Margaret J; Sassoon, Stephanie A; Thompson, Megan A; Pfefferbaum, Adolf; Sullivan, Edith V

2011-02-01

Impairments in component processes of working and episodic memory mark both HIV infection and chronic alcoholism, with compounded deficits often observed in individuals comorbid for these conditions. Remote semantic memory processes, however, have only seldom been studied in these diagnostic groups. Examination of remote semantic memory could provide insight into the underlying processes associated with storage and retrieval of learned information over extended time periods while elucidating spared and impaired cognitive functions in these clinical groups. We examined component processes of remote semantic memory in HIV infection and chronic alcoholism in 4 subject groups (HIV, ALC, HIV + ALC, and age-matched healthy adults) using a modified version of the Presidents Test. Free recall, recognition, and sequencing of presidential candidates and election dates were assessed. In addition, component processes of working, episodic, and semantic memory were assessed with ancillary cognitive tests. The comorbid group (HIV + ALC) was significantly impaired on sequencing of remote semantic information compared with age-matched healthy adults. Free recall of remote semantic information was also modestly impaired in the HIV + ALC group, but normal performance for recognition of this information was observed. Few differences were observed between the single diagnosis groups (HIV, ALC) and healthy adults, although examination of the component processes underlying remote semantic memory scores elicited differences between the HIV and ALC groups. Selective remote memory processes were related to lifetime alcohol consumption in the ALC group and to viral load and depression level in the HIV group. Hepatitis C diagnosis was associated with lower remote semantic memory scores in all 3 clinical groups. Education level did not account for group differences reported. This study provides behavioral support for the existence of adverse effects associated with the comorbidity of HIV infection and chronic alcoholism on selective component processes of memory function, with untoward effects exacerbated by Hepatitis C infection. The pattern of remote semantic memory function in HIV + ALC is consistent with those observed in neurological conditions primarily affecting frontostriatal pathways and suggests that remote memory dysfunction in HIV + ALC may be a result of impaired retrieval processes rather than loss of remote semantic information per se. Copyright © 2010 by the Research Society on Alcoholism.

The influence of strategic encoding on false memory in patients with mild cognitive impairment and Alzheimer's disease dementia.

PubMed

Tat, Michelle J; Soonsawat, Anothai; Nagle, Corinne B; Deason, Rebecca G; O'Connor, Maureen K; Budson, Andrew E

2016-11-01

Patients with Alzheimer's disease (AD) dementia exhibit high rates of memory distortions in addition to their impairments in episodic memory. Several investigations have demonstrated that when healthy individuals (young and old) engaged in an encoding strategy that emphasized the uniqueness of study items (an item-specific encoding strategy), they were able to improve their discrimination between old items and unstudied critical lure items in a false memory task. In the present study we examined if patients with AD could also improve their memory discrimination when engaging in an item-specific encoding strategy. Healthy older adult controls, patients with mild cognitive impairment (MCI) due to AD, and patients with mild AD dementia were asked to study lists of categorized words. In the Item-Specific condition, participants were asked to provide a unique detail or personal experience with each study item. In the Relational condition, they were asked to determine how each item in the list was related to the others. To assess the influence of both strategies, recall and recognition memory tests were administered. Overall, both patient groups exhibited poorer memory in both recall and recognition tests compared to controls. In terms of recognition, healthy older controls and patients with MCI due to AD exhibited improved memory discrimination in the Item-Specific condition compared to the Relational condition, whereas patients with AD dementia did not. We speculate that patients with MCI due to AD use intact frontal networks to effectively engage in this strategy. Published by Elsevier Inc.

The influence of strategic encoding on false memory in patients with mild cognitive impairment and Alzheimer’s disease dementia

PubMed Central

Tat, Michelle J.; Soonsawat, Anothai; Nagle, Corinne B.; Deason, Rebecca G.; O’Connor, Maureen K.; Budson, Andrew E.

2018-01-01

Patients with Alzheimer’s disease (AD) dementia exhibit high rates of memory distortions in addition to their impairments in episodic memory. Several investigations have demonstrated that when healthy individuals (young and old) engaged in an encoding strategy that emphasized the uniqueness of study items (an item-specific encoding strategy), they were able to improve their discrimination between old items and unstudied critical lure items in a false memory task. In the present study we examined if patients with AD could also improve their memory discrimination when engaging in an item-specific encoding strategy. Healthy older adult controls, patients with mild cognitive impairment (MCI) due to AD, and patients with mild AD dementia were asked to study lists of categorized words. In the Item-Specific condition, participants were asked to provide a unique detail or personal experience with each study item. In the Relational condition, they were asked to determine how each item in the list was related to the others. To assess the influence of both strategies, recall and recognition memory tests were administered. Overall, both patient groups exhibited poorer memory in both recall and recognition tests compared to controls. In terms of recognition, healthy older controls and patients with MCI due to AD exhibited improved memory discrimination in the Item-Specific condition compared to the Relational condition, whereas patients with AD dementia did not. We speculate that patients with MCI due to AD use intact frontal networks to effectively engage in this strategy. PMID:27643951

Effortful Retrieval Reduces Hippocampal Activity and Impairs Incidental Encoding

PubMed Central

Reas, Emilie T.; Brewer, James B.

2014-01-01

Functional imaging studies frequently report that the hippocampus is engaged by successful episodic memory retrieval. However, considering that concurrent encoding of the background environment occurs during retrieval and influences medial temporal lobe activity, it is plausible that hippocampal encoding functions are reduced with increased attentional engagement during effortful retrieval. Expanding upon evidence that retrieval efforts suppress activity in hippocampal regions implicated in encoding, this study examines the influence of retrieval effort on encoding performance and the interactive effects of encoding and retrieval on hippocampal and neocortical activity. Functional magnetic resonance imaging was conducted while subjects performed a word recognition task with incidental picture encoding. Both lower memory strength and increased search duration were associated with encoding failure and reduced hippocampal and default network activity. Activity in the anterior hippocampus tracked encoding, which was more strongly deactivated when incidental encoding was unsuccessful. These findings highlight potential contributions from background encoding processes to hippocampal activations during neuroimaging studies of episodic memory retrieval. PMID:23378272

Investigating the Functional Utility of the Left Parietal ERP Old/New Effect: Brain Activity Predicts within But Not between Participant Variance in Episodic Recollection

PubMed Central

MacLeod, Catherine A.; Donaldson, David I.

2017-01-01

A success story within neuroimaging has been the discovery of distinct neural correlates of episodic retrieval, providing insight into the processes that support memory for past life events. Here we focus on one commonly reported neural correlate, the left parietal old/new effect, a positive going modulation seen in event-related potential (ERP) data that is widely considered to index episodic recollection. Substantial evidence links changes in the size of the left parietal effect to changes in remembering, but the precise functional utility of the effect remains unclear. Here, using forced choice recognition of verbal stimuli, we present a novel population level test of the hypothesis that the magnitude of the left parietal effect correlates with memory performance. We recorded ERPs during old/new recognition, source accuracy and Remember/Know/Guess tasks in two large samples of healthy young adults, and successfully replicated existing within participant modulations of the magnitude of the left parietal effect with recollection. Critically, however, both datasets also show that across participants the magnitude of the left parietal effect does not correlate with behavioral measures of memory – including both subjective and objective estimates of recollection. We conclude that in these tasks, and across this healthy young adult population, the generators of the left parietal ERP effect do not index performance as expected. Taken together, these novel findings provide important constraints on the functional interpretation of the left parietal effect, suggesting that between group differences in the magnitude of old/new effects cannot always safely be used to infer differences in recollection. PMID:29259551

Discriminating Famous from Fictional Names Based on Lifetime Experience: Evidence in Support of a Signal-Detection Model Based on Finite Mixture Distributions

ERIC Educational Resources Information Center

Bowles, Ben; Harlow, Iain M.; Meeking, Melissa M.; Kohler, Stefan

2012-01-01

It is widely accepted that signal-detection mechanisms contribute to item-recognition memory decisions that involve discriminations between targets and lures based on a controlled laboratory study episode. Here, the authors employed mathematical modeling of receiver operating characteristics (ROC) to determine whether and how a signal-detection…

Preserved learning of novel information in amnesia: evidence for multiple memory systems.

PubMed

Gordon, B

1988-06-01

Four of five patients with marked global amnesia, and others with new learning impairments, showed normal processing facilitation for novel stimuli (nonwords) and/or for familiar stimuli (words) on a word/nonword (lexical) decision task. The data are interpreted as a reflection of the learning capabilities of in-line neural processing stages with multiple, distinct, informational codes. These in-line learning processes are separate from the recognition/recall memory impaired by amygdalohippocampal/dosomedial thalamic damage, but probably supplement such memory in some tasks in normal individuals. Preserved learning of novel information seems incompatible with explanations of spared learning in amnesia that are based on the episodic/semantic or memory/habit distinctions, but is consistent with the procedural/declarative hypothesis.

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

PubMed

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 stressful episode. Copyright © 2017 Elsevier Inc. All rights reserved.

Semantic processes leading to true and false memory formation in schizophrenia.

PubMed

Paz-Alonso, Pedro M; Ghetti, Simona; Ramsay, Ian; Solomon, Marjorie; Yoon, Jong; Carter, Cameron S; Ragland, J Daniel

2013-07-01

Encoding semantic relationships between items on word lists (semantic processing) enhances true memories, but also increases memory distortions. Episodic memory impairments in schizophrenia (SZ) are strongly driven by failures to process semantic relations, but the exact nature of these relational semantic processing deficits is not well understood. Here, we used a false memory paradigm to investigate the impact of implicit and explicit semantic processing manipulations on episodic memory in SZ. Thirty SZ and 30 demographically matched healthy controls (HC) studied Deese/Roediger-McDermott (DRM) lists of semantically associated words. Half of the lists had strong implicit semantic associations and the remainder had low strength associations. Similarly, half of the lists were presented under "standard" instructions and the other half under explicit "relational processing" instructions. After study, participants performed recall and old/new recognition tests composed of targets, critical lures, and unrelated lures. HC exhibited higher true memories and better discriminability between true and false memory compared to SZ. High, versus low, associative strength increased false memory rates in both groups. However, explicit "relational processing" instructions positively improved true memory rates only in HC. Finally, true and false memory rates were associated with severity of disorganized and negative symptoms in SZ. These results suggest that reduced processing of semantic relationships during encoding in SZ may stem from an inability to implement explicit relational processing strategies rather than a fundamental deficit in the implicit activation and retrieval of word meanings from patients' semantic lexicon. Copyright © 2013 Elsevier B.V. All rights reserved.

Interfering with memory for faces: The cost of doing two things at once.

PubMed

Wammes, Jeffrey D; Fernandes, Myra A

2016-01-01

We inferred the processes critical for episodic retrieval of faces by measuring susceptibility to memory interference from different distracting tasks. Experiment 1 examined recognition of studied faces under full attention (FA) or each of two divided attention (DA) conditions requiring concurrent decisions to auditorily presented letters. Memory was disrupted in both DA relative to FA conditions, a result contrary to a material-specific account of interference effects. Experiment 2 investigated whether the magnitude of interference depended on competition between concurrent tasks for common processing resources. Studied faces were presented either upright (configurally processed) or inverted (featurally processed). Recognition was completed under FA, or DA with one of two face-based distracting tasks requiring either featural or configural processing. We found an interaction: memory for upright faces was lower under DA when the distracting task required configural than featural processing, while the reverse was true for memory of inverted faces. Across experiments, the magnitude of memory interference was similar (a 19% or 20% decline from FA) regardless of whether the materials in the distracting task overlapped with the to-be-remembered information. Importantly, interference was significantly larger (42%) when the processing demands of the distracting and target retrieval task overlapped, suggesting a processing-specific account of memory interference.

Replay of Episodic Memories in the Rat.

PubMed

Panoz-Brown, Danielle; Iyer, Vishakh; Carey, Lawrence M; Sluka, Christina M; Rajic, Gabriela; Kestenman, Jesse; Gentry, Meredith; Brotheridge, Sydney; Somekh, Isaac; Corbin, Hannah E; Tucker, Kjersten G; Almeida, Bianca; Hex, Severine B; Garcia, Krysten D; Hohmann, Andrea G; Crystal, Jonathon D

2018-05-21

Vivid episodic memories in people have been characterized as the replay of multiple unique events in sequential order [1-3]. The hippocampus plays a critical role in episodic memories in both people and rodents [2, 4-6]. Although rats remember multiple unique episodes [7, 8], it is currently unknown if animals "replay" episodic memories. Therefore, we developed an animal model of episodic memory replay. Here, we show that rats can remember a trial-unique stream of multiple episodes and the order in which these events occurred by engaging hippocampal-dependent episodic memory replay. We document that rats rely on episodic memory replay to remember the order of events rather than relying on non-episodic memories. Replay of episodic memories survives a long retention-interval challenge and interference from the memory of other events, which documents that replay is part of long-term episodic memory. The chemogenetic activating drug clozapine N-oxide (CNO), but not vehicle, reversibly impairs episodic memory replay in rats previously injected bilaterally in the hippocampus with a recombinant viral vector containing an inhibitory designer receptor exclusively activated by a designer drug (DREADD; AAV8-hSyn-hM4Di-mCherry). By contrast, two non-episodic memory assessments are unaffected by CNO, showing selectivity of this hippocampal-dependent impairment. Our approach provides an animal model of episodic memory replay, a process by which the rat searches its representations in episodic memory in sequential order to find information. Our findings using rats suggest that the ability to replay a stream of episodic memories is quite old in the evolutionary timescale. Copyright © 2018 Elsevier Ltd. All rights reserved.

Verbal episodic memory in 426 multiple sclerosis patients: impairment in encoding, retrieval or both?

PubMed

Brissart, H; Morele, E; Baumann, C; Debouverie, M

2012-10-01

Episodic memory is frequently impaired in multiple sclerosis (MS) patients but the exact nature of the disorder is controversial. It was initially thought to be due to a retrieval deficit but some studies have demonstrated an encoding deficit, which could be linked to a slowing of information processing speed or to a deficit in elaboration of strategies. The main objective of this study is to assess the prevalence and the nature of verbal episodic memory (VEM) impairment in MS patients. We retrieved memory performances of 426 patients [314 F-112 M; mean age: 46.1 years; median Expanded Disability Status Scale (EDSS) score: 3.1] from a neuropsychological data base. VEM was assessed using the 16 words RL-RI 16 test. 66% MS patients present at least one recall impaired in VEM (37.2% from 2 to 5 recall). 14.2% MS patients present an impairment in encoding phase. We observed that 5% of patients presented recognition difficulties. Correlations were observed between VEM performances and EDSS, and disease duration but no group effect (ANOVA) is observed between form of MS and VEM performances. These results confirm the high prevalence of VEM impairment in MS patients. Deficits affect mainly information retrieval in early stage MS patients and are then linked to encoding as disability increases. Storage disorders are infrequent, so cognitive rehabilitation with mental imaging could be effective in MS patients.

Functional MRI study of diencephalic amnesia in Wernicke-Korsakoff syndrome.

PubMed

Caulo, M; Van Hecke, J; Toma, L; Ferretti, A; Tartaro, A; Colosimo, C; Romani, G L; Uncini, A

2005-07-01

Anterograde amnesia in Wernicke-Korsakoff syndrome is associated with diencephalic lesions, mainly in the anterior thalamic nuclei. Whether diencephalic and temporal lobe amnesias are distinct entities is still not clear. We investigated episodic memory for faces using functional MRI (fMRI) in eight controls and in a 34-year-old man with Wernicke-Korsakoff syndrome and diencephalic lesions but without medial temporal lobe (MTL) involvement at MRI. fMRI was performed with a 1.5 tesla unit. Three dual-choice tasks were employed: (i) face encoding (18 faces were randomly presented three times and subjects were asked to memorize the faces); (ii) face perception (subjects indicated which of two faces matched a third face); and (iii) face recognition (subjects indicated which of two faces belonged to the group they had been asked to memorize during encoding). All activation was greater in the right hemisphere. In controls both the encoding and recognition tasks activated two hippocampal regions (anterior and posterior). The anterior hippocampal region was more activated during recognition. Activation in the prefrontal cortex was greater during recognition. In the subject with Wernicke-Korsakoff syndrome, fMRI did not show hippocampal activation during either encoding or recognition. During recognition, although behavioural data showed defective retrieval, the prefrontal regions were activated as in controls, except for the ventrolateral prefrontal cortex. fMRI activation of the visual cortices and the behavioural score on the perception task indicated that the subject with Wernicke-Korsakoff syndrome perceived the faces, paid attention to the task and demonstrated accurate judgement. In the subject with Wernicke-Korsakoff syndrome, although the anatomical damage does not involve the MTL, the hippocampal memory encoding has been lost, possibly as a consequence of the hippocampal-anterior thalamic axis involvement. Anterograde amnesia could therefore be the expression of damage to an extended hippocampal system, and the distinction between temporal lobe and diencephalic amnesia has limited value. In the subject with Wernicke-Korsakoff syndrome, the preserved dorsolateral prefrontal cortex activation during incorrect recognition suggests that this region is more involved in either the orientation or attention at retrieval than in retrieval. The lack of activation of the prefrontal ventrolateral cortex confirms the role of this area in episodic memory formation.

Preliminary data on a mnemonic instrument with proverbs for tracking Alzheimer's disease.

PubMed

Santos, Mauricéa Tabósa Ferreira; Guerra, Gutemberg; de Menezes, Terce Liana; Carvalho, Tatiana Lins; Alchieri, João Carlos; Sougey, Everton Botelho

2008-01-01

In the differential diagnosis between Alzheimer's disease (AD) and normal aging, tests evaluating memory and executive functions are frequently used. The addition of abstraction tests may enhance the effectiveness of screening tests for AD. The aim of this study was to compare initial data of a new instrument - The Screening Test for Alzheimer's Disease with Proverbs (STADP) - against other screening tests used in AD diagnosis. Sixty elderly individuals (46 controls and 14 AD subjects with CDR=1), aged =60 years, with at least one year of schooling, were evaluated using the STADP at outpatient clinic. The STADP assesses short-term memory, episodic memory, executive functions and language, in addition to proverb recognition. The performance of the participants on the Mini-Mental State Examination (MMSE), semantic Verbal Fluency (VF) and Clock Drawing Test (CDT) were evaluated and the habit of reading, writing and sociodemographic data were also taken into account. There were significant correlations between STADP and the performance on the MMSE (r=0.64), CDT (r=0.50) and VF (r=0.56). Age influenced all sub-items of the STADP, specifically episodic memory (r= -0.54), whereas schooling mainly influenced executive functions and language (r=0.46). The total score, stages A and C and the "proverb recognition" of STADP (p<0.001), as well as the MMSE (p<0.001), CDT (p=0.016), VF (p<0.001) were significantly different in AD versus control groups. The findings point to the potential use of the STADP in AD, warranting the conducting of further studies.

Everyday memory impairment in patients with temporal lobe epilepsy caused by hippocampal sclerosis.

PubMed

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

2017-04-01

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

[Analysis of intrusion errors in free recall].

PubMed

Diesfeldt, H F A

2017-06-01

Extra-list intrusion errors during five trials of the eight-word list-learning task of the Amsterdam Dementia Screening Test (ADST) were investigated in 823 consecutive psychogeriatric patients (87.1% suffering from major neurocognitive disorder). Almost half of the participants (45.9%) produced one or more intrusion errors on the verbal recall test. Correct responses were lower when subjects made intrusion errors, but learning slopes did not differ between subjects who committed intrusion errors and those who did not so. Bivariate regression analyses revealed that participants who committed intrusion errors were more deficient on measures of eight-word recognition memory, delayed visual recognition and tests of executive control (the Behavioral Dyscontrol Scale and the ADST-Graphical Sequences as measures of response inhibition). Using hierarchical multiple regression, only free recall and delayed visual recognition retained an independent effect in the association with intrusion errors, such that deficient scores on tests of episodic memory were sufficient to explain the occurrence of intrusion errors. Measures of inhibitory control did not add significantly to the explanation of intrusion errors in free recall, which makes insufficient strength of memory traces rather than a primary deficit in inhibition the preferred account for intrusion errors in free recall.

Postencephalitic focal retrograde amnesia after bilateral anterior temporal lobe damage.

PubMed

Tanaka, Y; Miyazawa, Y; Hashimoto, R; Nakano, I; Obayashi, T

1999-07-22

Marked retrograde amnesia with no or almost no anterograde amnesia is rare. Recently, a combination of ventrolateral prefrontal and temporopolar cortical lesions has been suggested as the cause of such isolated or focal retrograde amnesia. It is also assumed that when the right-sided cortical structures are damaged, autobiographical episodic memories are affected. To search for new anatomic substrates for focal retrograde amnesia. We performed extensive neuropsychological tests and obtained detailed neuroimages on a 43-year-old woman who showed a severe, persistent retrograde amnesia but only a limited anterograde amnesia after probable herpes simplex encephalitis. Tests of autobiographical memory revealed that she had a memory loss extending back to her childhood for both semantics and incidents; however, the ability to recall specific episodes appeared much more severely impaired than the ability to recall factual information about her past. The patient also showed profound impairments in recalling public memories; however, her scores improved nearly to a control level on forced-choice recognition memory tasks, although the recall of memories for a decade just before her illness remained mildly impaired. MRI revealed focal pathologies in the temporal poles and the anterior parts of the inferotemporal lobes on both sides, predominantly on the left, with some extension to the anterior parts of the medial temporal lobes. There was additional damage to the left insular cortex and its surrounding structures but no evidence of frontal lobe damage on MRIs or cognitive tests. A profound retrograde amnesia may be produced by damage to the bilateral temporal poles and anterior inferotemporal lobes in the absence of frontal lobe pathologies, and a dense and persistent episodic old memory loss can arise even with a relatively small lesion in the right anterior temporal lobe if it is combined with extensive damage to the left.

Meta-analytic Review of Memory Impairment in Behavioral Variant Frontotemporal Dementia.

PubMed

Poos, Jackie M; Jiskoot, Lize C; Papma, Janne M; van Swieten, John C; van den Berg, Esther

2018-03-19

A meta-analysis of the extent, nature and pattern of memory performance in behavioral variant frontotemporal dementia (bvFTD). Multiple observational studies have challenged the relative sparing of memory in bvFTD as stated in the current diagnostic criteria. We performed a meta-analytic review covering the period 1967 to February 2017 of case-control studies on episodic memory in bvFTD versus control participants (16 studies, 383 patients, 603 control participants), and patients with bvFTD versus those with Alzheimer's disease (AD) (20 studies, 452 bvFTD, 874 AD). Differences between both verbal and non-verbal working memory, episodic memory learning and recall, and recognition memory were examined. Data were extracted from the papers and combined into a common metric measure of effect, Hedges' d. Patients with bvFTD show large deficits in memory performance compared to controls (Hedges' d -1.10; 95% confidence interval [CI] [-1.23, -0.95]), but perform significantly better than patients with AD (Hedges' d 0.85; 95% CI [0.69, 1.03]). Learning and recall tests differentiate best between patients with bvFTD and AD (p<.01). There is 37-62% overlap in test scores between the two groups. This study points to memory disorders in patients with bvFTD, with performance at an intermediate level between controls and patients with AD. This indicates that, instead of being an exclusion criterion for bvFTD diagnosis, memory deficits should be regarded as a potential integral part of the clinical spectrum. (JINS, 2018, 24, 1-13).

The contributions of handedness and working memory to episodic memory.

PubMed

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

2016-11-01

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

Perspectives on Episodic-Like and Episodic Memory

PubMed Central

Pause, Bettina M.; Zlomuzica, Armin; Kinugawa, Kiyoka; Mariani, Jean; Pietrowsky, Reinhard; Dere, Ekrem

2013-01-01

Episodic memory refers to the conscious recollection of a personal experience that contains information on what has happened and also where and when it happened. Recollection from episodic memory also implies a kind of first-person subjectivity that has been termed autonoetic consciousness. Episodic memory is extremely sensitive to cerebral aging and neurodegenerative diseases. In Alzheimer’s disease deficits in episodic memory function are among the first cognitive symptoms observed. Furthermore, impaired episodic memory function is also observed in a variety of other neuropsychiatric diseases including dissociative disorders, schizophrenia, and Parkinson disease. Unfortunately, it is quite difficult to induce and measure episodic memories in the laboratory and it is even more difficult to measure it in clinical populations. Presently, the tests used to assess episodic memory function do not comply with even down-sized definitions of episodic-like memory as a memory for what happened, where, and when. They also require sophisticated verbal competences and are difficult to apply to patient populations. In this review, we will summarize the progress made in defining behavioral criteria of episodic-like memory in animals (and humans) as well as the perspectives in developing novel tests of human episodic memory which can also account for phenomenological aspects of episodic memory such as autonoetic awareness. We will also define basic behavioral, procedural, and phenomenological criteria which might be helpful for the development of a valid and reliable clinical test of human episodic memory. PMID:23616754

Older adults' use of metacognitive knowledge in source monitoring: spared monitoring but impaired control.

PubMed

Kuhlmann, Beatrice G; Touron, Dayna R

2011-03-01

While episodic memory declines with age, metacognitive monitoring is spared. The current study explored whether older adults can use their preserved metacognitive knowledge to make source guesses in the absence of source memory. Through repetition, words from two sources (italic vs. bold text type) differed in memorability. There were no age differences in monitoring this difference despite an age difference in memory. Older adults used their metacognitive knowledge to make source guesses but showed a deficit in varying their source guessing based on word recognition. Therefore, older adults may not fully benefit from metacognitive knowledge about sources in source monitoring. (c) 2011 APA, all rights reserved.

Memory sources of dreams: the incorporation of autobiographical rather than episodic experiences.

PubMed

Malinowski, Josie E; Horton, Caroline L

2014-08-01

The present study aimed to explore autobiographical memories (long-lasting memories about the self) and episodic memories (memories about discrete episodes or events) within dream content. We adapted earlier episodic memory study paradigms and reinvestigated the incorporation of episodic memory sources into dreams, operationalizing episodic memory as featuring autonoetic consciousness, which is the feeling of truly re-experiencing or reliving a past event. Participants (n = 32) recorded daily diaries and dream diaries, and reported on wake-dream relations for 2 weeks. Using a new scale, dreams were rated for their episodic richness, which categorized memory sources of dreams as being truly episodic (featuring autonoetic consciousness), autobiographical (containing segregated features of experiences that pertained to waking life) or otherwise. Only one dream (0.5%) was found to contain an episodic memory. However, the majority of dreams (>80%) were found to contain low to moderate incorporations of autobiographical memory features. These findings demonstrate the inactivity of intact episodic memories, and emphasize the activity of autobiographical memory and processing within dreams. Taken together, this suggests that memories for personal experiences are experienced fragmentarily and selectively during dreaming, perhaps in order to assimilate these memories into the autobiographical memory schema. © 2014 European Sleep Research Society.

Human-machine interactions

DOEpatents

Forsythe, J Chris [Sandia Park, NM; Xavier, Patrick G [Albuquerque, NM; Abbott, Robert G [Albuquerque, NM; Brannon, Nathan G [Albuquerque, NM; Bernard, Michael L [Tijeras, NM; Speed, Ann E [Albuquerque, NM

2009-04-28

Digital technology utilizing a cognitive model based on human naturalistic decision-making processes, including pattern recognition and episodic memory, can reduce the dependency of human-machine interactions on the abilities of a human user and can enable a machine to more closely emulate human-like responses. Such a cognitive model can enable digital technology to use cognitive capacities fundamental to human-like communication and cooperation to interact with humans.

Cognitive and subjective acute dose effects of intramuscular ketamine in healthy adults.

PubMed

Lofwall, Michelle R; Griffiths, Roland R; Mintzer, Miriam Z

2006-11-01

Ketamine is a noncompetitive N-methyl-D-aspartate (NMDA) antagonist. Given the purported role of the NMDA receptor in long-term potentiation, the primary purpose of the present study was to further understand the dose-related effects of ketamine on memory. The study was also designed to provide information about the relative effects of ketamine on memory versus nonmemory effects and to more fully characterize ketamine's overall pattern and time course of effects. Single intramuscular injections of ketamine (0.2 mg/kg, 0.4 mg/kg) were administered to 18 healthy adult volunteers using a double-blind, placebo-controlled, crossover design. Word lists were used to evaluate episodic memory (free recall, recognition memory, source memory) and metamemory. Working memory, time estimation, psychomotor performance, and subjective effects were assessed repeatedly for 5 hours after drug administration. Ketamine selectively impaired encoding (as measured by free recall) while sparing retrieval, working memory while sparing attention, and digit symbol substitution task speed while sparing accuracy. Ketamine did not significantly impair recognition or source memory, metamemory, or time estimation. There were no hallucinations or increases in mystical experiences with ketamine. Memory measures were less sensitive to ketamine effects than subjective or psychomotor measures. Subjective effects lasted longer than memory and most psychomotor impairments. Ketamine produces selective, transient, dose- and time-related effects. In conjunction with previous studies of drugs with different mechanisms of actions, the observed selectivity of effects enhances the understanding of the pharmacological mechanisms underlying memory, attention, psychomotor performance, and subjective experience.

Capturing real-life forgetting in transient epileptic amnesia via an incidental memory test.

PubMed

Hoefeijzers, Serge; Zeman, Adam; Della Sala, Sergio; Dewar, Michaela

2017-12-13

Transient epileptic amnesia (TEA) is an epileptic syndrome characterized by recurrent, brief episodes of amnesia. Patients with TEA often complain of interictal (between attacks) retention deficits, characterised by an 'evaporation' of memories for recent events over days to weeks. Clinical tests of anterograde memory often fail to corroborate these complaints as TEA patients commonly perform within the normal range after the standard 10-30-min delay period. Modified laboratory tests that include a 1-3 week delay period frequently reveal clear evidence of 'accelerated long-term forgetting' (ALF). However, they are not used routinely and lack ecological validity. In the present study we examined whether 'real-life' ALF can be captured via a controlled incidental memory test in TEA patients. To this end, the experimenter told 27 TEA patients and 32 controls a well-rehearsed amusing story, apparently as a way of making light conversation before starting a set of research experiments. Without prior warning, the experimenter subsequently probed the participants' memory of this story via tests of free recall and forced choice recognition after 30 min or 1 week. After 30 min retention was comparable in TEA patients and controls. After 1 week TEA patients retained significantly less story material than controls, and significant ALF was revealed in the TEA patients in the recognition test. Our data show that ALF in a 'real-life' situation can occur even when standard memory tests indicate normal memory function. Moreover, our data suggest that incidental memory tests can capture real-life ALF, and that forced-choice recognition tests might be more sensitive than free recall tests for the detection of real-life ALF. Copyright © 2017 Elsevier Ltd. All rights reserved.

Computerised working memory based cognitive remediation therapy does not affect Reading the Mind in the Eyes test performance or neural activity during a Facial Emotion Recognition test in psychosis.

PubMed

Mothersill, David; Dillon, Rachael; Hargreaves, April; Castorina, Marco; Furey, Emilia; Fagan, Andrew J; Meaney, James F; Fitzmaurice, Brian; Hallahan, Brian; McDonald, Colm; Wykes, Til; Corvin, Aiden; Robertson, Ian H; Donohoe, Gary

2018-05-27

Working memory based cognitive remediation therapy (CT) for psychosis has recently been associated with broad improvements in performance on untrained tasks measuring working memory, episodic memory and IQ, and changes in associated brain regions. However, it is unclear if these improvements transfer to the domain of social cognition and neural activity related to performance on social cognitive tasks. We examined performance on the Reading the Mind in the Eyes test (Eyes test) in a large sample of participants with psychosis who underwent working memory based CT (N = 43) compared to a Control Group of participants with psychosis (N = 35). In a subset of this sample, we used functional magnetic resonance imaging (fMRI) to examine changes in neural activity during a facial emotion recognition task in participants who underwent CT (N = 15) compared to a Control Group (N = 15). No significant effects of CT were observed on Eyes test performance or on neural activity during facial emotion recognition, either at p<0.05 family-wise error, or at a p<0.001 uncorrected threshold, within a priori social cognitive regions of interest. This study suggests that working memory based CT does not significantly impact an aspect of social cognition which was measured behaviourally and neurally. It provides further evidence that deficits in the ability to decode mental state from facial expressions are dissociable from working memory deficits, and suggests that future CT programs should target social cognition in addition to working memory for the purposes of further enhancing social function. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Episodic memories.

PubMed

Conway, Martin A

2009-09-01

An account of episodic memories is developed that focuses on the types of knowledge they represent, their properties, and the functions they might serve. It is proposed that episodic memories consist of episodic elements, summary records of experience often in the form of visual images, associated to a conceptual frame that provides a conceptual context. Episodic memories are embedded in a more complex conceptual system in which they can become the basis of autobiographical memories. However, the function of episodic memories is to keep a record of progress with short-term goals and access to most episodic memories is lost soon after their formation. Finally, it is suggested that developmentally episodic memories form the basis of the conceptual system and it is from sets of episodic memories that early non-verbal conceptual knowledge is abstracted.

An Event Related Potentials Study of Semantic Coherence Effect during Episodic Encoding in Schizophrenia Patients

PubMed Central

Blanchet, Alain; Lockman, Hazlin

2018-01-01

The objective of this electrophysiological study was to investigate the processing of semantic coherence during encoding in relation to episodic memory processes promoted at test, in schizophrenia patients, by using the N400 paradigm. Eighteen schizophrenia patients and 15 healthy participants undertook a recognition memory task. The stimuli consisted of pairs of words either semantically related or unrelated to a given category name (context). During encoding, both groups exhibited an N400 external semantic coherence effect. Healthy controls also showed an N400 internal semantic coherence effect, but this effect was not present in patients. At test, related stimuli were accompanied by an FN400 old/new effect in both groups and by a parietal old/new effect in the control group alone. In the patient group, external semantic coherence effect was associated with FN400, while, in the control group, it was correlated to the parietal old/new effect. Our results indicate that schizophrenia patients can process the contextual information at encoding to enhance familiarity process for related stimuli at test. Therefore, cognitive rehabilitation therapies targeting the implementation of semantic encoding strategies can mobilize familiarity which in turn can overcome the recollection deficit, promoting successful episodic memory performance in schizophrenia patients. PMID:29535872

The influence of seizure frequency on anterograde and remote memory in mesial temporal lobe epilepsy.

PubMed

Voltzenlogel, Virginie; Vignal, Jean-Pierre; Hirsch, Edouard; Manning, Liliann

2014-10-01

Seizure frequency, although considered as an important factor in memory impairment in mesial temporal epilepsy (mTLE), is mostly confounded with other clinical variables, making it unclear to what extent recurrent seizures actually interfere with memory. The present study focuses on the influence of seizure frequency, studied as a main variable, on anterograde and remote memory. Seventy-one patients with unilateral mTLE were divided into two subgroups, as a function of their seizure frequency (monthly versus weekly seizures). Other seizure-related variables were controlled, namely, lateralisation and type of lesion, age at onset, years of ongoing seizures, etiologic factors, and number of AED. A comprehensive neuropsychological examination, including anterograde memory (verbal and non verbal recognition memory and free recall) tasks together with a large range of tests exploring different domains of remote memory, was carried out. Despite similar results on IQ, executive functions and attention, the low seizure-frequency group performed significantly better than the high seizure-frequency group on anterograde memory tests. Loss of autobiographical episodes and public-events memory, concomitant with spared personal semantic knowledge, was observed in both patient groups compared with healthy subjects. A worsening effect of high seizure frequency was recorded for autobiographical incidents and news-events memory, but unexpectedly, not for memory for famous people. The study of seizure frequency as the main variable leads us to suggest that high seizure frequency, itself, potentiates the effects of mesial temporal lobe damage on episodic memory deficits. Copyright © 2014 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Visual Memory in Methamphetamine Dependent Individuals: Deficient Strategic Control of Encoding and Retrieval

PubMed Central

Morgan, Erin E.; Woods, Steven Paul; Poquette, Amelia J.; Vigil, Ofilio; Heaton, Robert K.; Grant, Igor

2012-01-01

Objective Chronic use of methamphetamine (MA) has moderate effects on neurocognitive functions associated with frontal systems, including the executive aspects of verbal episodic memory. Extending this literature, the current study examined the effects of MA on visual episodic memory with the hypothesis that a profile of deficient strategic encoding and retrieval processes would be revealed for visuospatial information (i.e., simple geometric designs), including possible differential effects on source versus item recall. Method The sample comprised 114 MA-dependent (MA+) and 110 demographically-matched MA-nondependent comparison participants (MA−) who completed the Brief Visuospatial Memory Test – Revised (BVMT-R), which was scored for standard learning and memory indices, as well as novel item (i.e., figure) and source (i.e., location) memory indices. Results Results revealed a profile of impaired immediate and delayed free recall (p < .05) in the context of preserved learning slope, retention, and recognition discriminability in the MA+ group. The MA+ group also performed more poorly than MA− participants on Item visual memory (p < .05) but not Source visual memory (p > .05), and no group by task-type interaction was observed (p > .05). Item visual memory demonstrated significant associations with executive dysfunction, deficits in working memory, and shorter length of abstinence from MA use (p < 0.05). Conclusions These visual memory findings are commensurate with studies reporting deficient strategic verbal encoding and retrieval in MA users that are posited to reflect the vulnerability of frontostriatal circuits to the neurotoxic effects of MA. Potential clinical implications of these visual memory deficits are discussed. PMID:22311530

Support for an auto-associative model of spoken cued recall: evidence from fMRI.

PubMed

de Zubicaray, Greig; McMahon, Katie; Eastburn, Mathew; Pringle, Alan J; Lorenz, Lina; Humphreys, Michael S

2007-03-02

Cued recall and item recognition are considered the standard episodic memory retrieval tasks. However, only the neural correlates of the latter have been studied in detail with fMRI. Using an event-related fMRI experimental design that permits spoken responses, we tested hypotheses from an auto-associative model of cued recall and item recognition [Chappell, M., & Humphreys, M. S. (1994). An auto-associative neural network for sparse representations: Analysis and application to models of recognition and cued recall. Psychological Review, 101, 103-128]. In brief, the model assumes that cues elicit a network of phonological short term memory (STM) and semantic long term memory (LTM) representations distributed throughout the neocortex as patterns of sparse activations. This information is transferred to the hippocampus which converges upon the item closest to a stored pattern and outputs a response. Word pairs were learned from a study list, with one member of the pair serving as the cue at test. Unstudied words were also intermingled at test in order to provide an analogue of yes/no recognition tasks. Compared to incorrectly rejected studied items (misses) and correctly rejected (CR) unstudied items, correctly recalled items (hits) elicited increased responses in the left hippocampus and neocortical regions including the left inferior prefrontal cortex (LIPC), left mid lateral temporal cortex and inferior parietal cortex, consistent with predictions from the model. This network was very similar to that observed in yes/no recognition studies, supporting proposals that cued recall and item recognition involve common rather than separate mechanisms.

[Role of context recall in destination memory decline in normal aging].

PubMed

El Haj, Mohamad; Allain, Philippe

2014-12-01

Until recently, little was known about destination memory, or memory for the destination of outputted information. In the present work, this memory was evaluated in 32 older adults and 36 younger adults, who had to associate proverbs to pictures of famous people and decide, on a subsequent recognition task, whether they had previously told that proverb to that face or not. When deciding about the destination, participants had to provide contextual judgment, that is, whether each picture had been previously exposed in color or in black and white. Participants also performed a neuropsychological battery tapping episodic memory and executive functions. Findings showed poor destination recall in older participants. Destination recall in older adults was reliably predicted by with their context recall. Destination memory seems to be particularly affected by aging, a deterioration that can be related to deficits in processing contextual features during encoding.

Repeated cognitive stimulation alleviates memory impairments in an Alzheimer's disease mouse model.

PubMed

Martinez-Coria, Hilda; Yeung, Stephen T; Ager, Rahasson R; Rodriguez-Ortiz, Carlos J; Baglietto-Vargas, David; LaFerla, Frank M

2015-08-01

Alzheimer's disease is a neurodegenerative disease associated with progressive memory and cognitive decline. Previous studies have identified the benefits of cognitive enrichment on reducing disease pathology. Additionally, epidemiological and clinical data suggest that repeated exercise, and cognitive and social enrichment, can improve and/or delay the cognitive deficiencies associated with aging and neurodegenerative diseases. In the present study, 3xTg-AD mice were exposed to a rigorous training routine beginning at 3 months of age, which consisted of repeated training in the Morris water maze spatial recognition task every 3 months, ending at 18 months of age. At the conclusion of the final Morris water maze training session, animals subsequently underwent testing in another hippocampus-dependent spatial task, the Barnes maze task, and on the more cortical-dependent novel object recognition memory task. Our data show that periodic cognitive enrichment throughout aging, via multiple learning episodes in the Morris water maze task, can improve the memory performance of aged 3xTg-AD mice in a separate spatial recognition task, and in a preference memory task, when compared to naïve aged matched 3xTg-AD mice. Furthermore, we observed that the cognitive enrichment properties of Morris water maze exposer, was detectable in repeatedly trained animals as early as 6 months of age. These findings suggest early repeated cognitive enrichment can mitigate the diverse cognitive deficits observed in Alzheimer's disease. Published by Elsevier Inc.

Age-related reduction of the confidence-accuracy relationship in episodic memory: effects of recollection quality and retrieval monitoring.

PubMed

Wong, Jessica T; Cramer, Stefanie J; Gallo, David A

2012-12-01

We investigated age-related reductions in episodic metamemory accuracy. Participants studied pictures and words in different colors and then took forced-choice recollection tests. These tests required recollection of the earlier presentation color, holding familiarity of the response options constant. Metamemory accuracy was assessed for each participant by comparing recollection test accuracy with corresponding confidence judgments. We found that recollection test accuracy was greater in younger than older adults and also for pictures than font color. Metamemory accuracy tracked each of these recollection differences, as well as individual differences in recollection test accuracy within each age group, suggesting that recollection ability affects metamemory accuracy. Critically, the age-related impairment in metamemory accuracy persisted even when the groups were matched on recollection test accuracy, suggesting that metamemory declines were not entirely due to differences in recollection frequency or quantity, but that differences in recollection quality and/or monitoring also played a role. We also found that age-related impairments in recollection and metamemory accuracy were equivalent for pictures and font colors. This result contrasted with previous false recognition findings, which predicted that older adults would be differentially impaired when monitoring memory for less distinctive memories. These and other results suggest that age-related reductions in metamemory accuracy are not entirely attributable to false recognition effects, but also depend heavily on deficient recollection and/or monitoring of specific details associated with studied stimuli. 2013 APA, all rights reserved

The role of relational binding in item memory: evidence from face recognition in a case of developmental amnesia.

PubMed

Olsen, Rosanna K; Lee, Yunjo; Kube, Jana; Rosenbaum, R Shayna; Grady, Cheryl L; Moscovitch, Morris; Ryan, Jennifer D

2015-04-01

Current theories state that the hippocampus is responsible for the formation of memory representations regarding relations, whereas extrahippocampal cortical regions support representations for single items. However, findings of impaired item memory in hippocampal amnesics suggest a more nuanced role for the hippocampus in item memory. The hippocampus may be necessary when the item elements need to be bound within and across episodes to form a lasting representation that can be used flexibly. The current investigation was designed to test this hypothesis in face recognition. H.C., an individual who developed with a compromised hippocampal system, and control participants incidentally studied individual faces that either varied in presentation viewpoint across study repetitions or remained in a fixed viewpoint across the study repetitions. Eye movements were recorded during encoding and participants then completed a surprise recognition memory test. H.C. demonstrated altered face viewing during encoding. Although the overall number of fixations made by H.C. was not significantly different from that of controls, the distribution of her viewing was primarily directed to the eye region. Critically, H.C. was significantly impaired in her ability to subsequently recognize faces studied from variable viewpoints, but demonstrated spared performance in recognizing faces she encoded from a fixed viewpoint, implicating a relationship between eye movement behavior in the service of a hippocampal binding function. These findings suggest that a compromised hippocampal system disrupts the ability to bind item features within and across study repetitions, ultimately disrupting recognition when it requires access to flexible relational representations. Copyright © 2015 the authors 0270-6474/15/355342-09$15.00/0.

Prefrontal and medial temporal contributions to episodic memory-based reasoning.

PubMed

Suzuki, Chisato; Tsukiura, Takashi; Mochizuki-Kawai, Hiroko; Shigemune, Yayoi; Iijima, Toshio

2009-03-01

Episodic memory retrieval and reasoning are fundamental psychological components of our daily lives. Although previous studies have investigated the brain regions associated with these processes separately, the neural mechanisms of reasoning based on episodic memory retrieval are largely unknown. Here, we investigated the neural correlates underlying episodic memory-based reasoning using functional magnetic resonance imaging (fMRI). During fMRI scanning, subjects performed three tasks: reasoning, episodic memory retrieval, and episodic memory-based reasoning. We identified dissociable activations related to reasoning, episodic memory retrieval, and linking processes between the two. Regions related to reasoning were identified in the left ventral prefrontal cortices (PFC), and those related to episodic memory retrieval were found in the right medial temporal lobe (MTL) regions. In addition, activations predominant in the linking process between the two were found in the left dorsal and right ventral PFC. These findings suggest that episodic memory-based reasoning is composed of at least three processes, i.e., reasoning, episodic memory retrieval, and linking processes between the two, and that activation of both the PFC and MTL is crucial in episodic memory-based reasoning. These findings are the first to demonstrate that PFC and MTL regions contribute differentially to each process in episodic memory-based reasoning.

On the functional significance of retrieval mode: Task switching disrupts the recollection of conceptual stimulus information from episodic memory.

PubMed

Küper, Kristina

2018-01-01

Episodic memory retrieval is assumed to be associated with the tonic cognitive state of retrieval mode. Despite extensive research into the neurophysiological correlates of retrieval mode, as of yet, relatively little is known about its functional significance. The present event-related potential (ERP) study was aimed at examining the impact of retrieval mode on the specificity of memory content retrieved in the course of familiarity and recollection processes. In two experiments, participants performed a recognition memory inclusion task in which they had to distinguish identically repeated and re-colored versions of study items from new items. In Experiment 1, participants had to alternate between the episodic memory task and a semantic task requiring a natural/artificial decision. In Experiment 2, the two tasks were instead performed in separate blocks. ERPs locked to the preparatory cues in the test phases indicated that participants did not establish retrieval mode on switch trials in Experiment 1. In the absence of retrieval mode, neither type of studied item elicited ERP correlates of familiarity-based retrieval (FN400). Recollection-related late positive complex (LPC) old/new effects emerged only for identically repeated but not for conceptually identical but perceptually changed versions of study items. With blocked retrieval in Experiment 2, both types of old items instead elicited equivalent FN400 and LPC old/new effects. The LPC data indicate that retrieval mode may play an important role in the successful recollection of conceptual stimulus information. The FN400 results additionally suggest that task switching may have a detrimental effect on familiarity-based memory retrieval. Copyright © 2017 Elsevier B.V. All rights reserved.

The evolution of episodic memory

PubMed Central

Allen, Timothy A.; Fortin, Norbert J.

2013-01-01

One prominent view holds that episodic memory emerged recently in humans and lacks a “(neo)Darwinian evolution” [Tulving E (2002) Annu Rev Psychol 53:1–25]. Here, we review evidence supporting the alternative perspective that episodic memory has a long evolutionary history. We show that fundamental features of episodic memory capacity are present in mammals and birds and that the major brain regions responsible for episodic memory in humans have anatomical and functional homologs in other species. We propose that episodic memory capacity depends on a fundamental neural circuit that is similar across mammalian and avian species, suggesting that protoepisodic memory systems exist across amniotes and, possibly, all vertebrates. The implication is that episodic memory in diverse species may primarily be due to a shared underlying neural ancestry, rather than the result of evolutionary convergence. We also discuss potential advantages that episodic memory may offer, as well as species-specific divergences that have developed on top of the fundamental episodic memory architecture. We conclude by identifying possible time points for the emergence of episodic memory in evolution, to help guide further research in this area. PMID:23754432

Testing episodic memory in animals: a new approach.

PubMed

Griffiths, D P; Clayton, N S

2001-08-01

Episodic memory involves the encoding and storage of memories concerned with unique personal experiences and their subsequent recall, and it has long been the subject of intensive investigation in humans. According to Tulving's classical definition, episodic memory "receives and stores information about temporally dated episodes or events and temporal-spatial relations among these events." Thus, episodic memory provides information about the 'what' and 'when' of events ('temporally dated experiences') and about 'where' they happened ('temporal-spatial relations'). The storage and subsequent recall of this episodic information was thought to be beyond the memory capabilities of nonhuman animals. Although there are many laboratory procedures for investigating memory for discrete past episodes, until recently there were no previous studies that fully satisfied the criteria of Tulving's definition: they can all be explained in much simpler terms than episodic memory. However, current studies of memory for cache sites in food-storing jays provide an ethologically valid model for testing episodic-like memory in animals, thereby bridging the gap between human and animal studies memory. There is now a pressing need to adapt these experimental tests of episodic memory for other animals. Given the potential power of transgenic and knock-out procedures for investigating the genetic and molecular bases of learning and memory in laboratory rodents, not to mention the wealth of knowledge about the neuroanatomy and neurophysiology of the rodent hippocampus (a brain area heavily implicated in episodic memory), an obvious next step is to develop a rodent model of episodic-like memory based on the food-storing bird paradigm. The development of a rodent model system could make an important contribution to our understanding of the neural, molecular, and behavioral mechanisms of mammalian episodic memory.

Sleep Reduces False Memory in Healthy Older Adults

PubMed Central

Lo, June C.; Sim, Sam K. Y.; Chee, Michael W. L.

2014-01-01

Study Objectives: To investigate the effects of post-learning sleep and sleep architecture on false memory in healthy older adults. Design: Balanced, crossover design. False memory was induced using the Deese-Roediger-McDermott (DRM) paradigm and assessed following nocturnal sleep and following a period of daytime wakefulness. Post-learning sleep structure was evaluated using polysomnography (PSG). Setting: Sleep research laboratory. Participants: Fourteen healthy older adults from the Singapore-Longitudinal Aging Brain Study (mean age ± standard deviation = 66.6 ± 4.1 y; 7 males). Measurements and Results: At encoding, participants studied lists of words that were semantically related to non-presented critical lures. At retrieval, they made “remember”/“know” and “new” judgments. Compared to wakefulness, post-learning sleep was associated with reduced “remember” responses, but not “know” responses to critical lures. In contrast, there were no significant differences in the veridical recognition of studied words, false recognition of unrelated distractors, discriminability, or response bias between the sleep and the wake conditions. More post-learning slow wave sleep was associated with greater reduction in false memory. Conclusions: In healthy older adults, sleep facilitates the reduction in false memory without affecting veridical memory. This benefit correlates with the amount of slow wave sleep in the post-learning sleep episode. Citation: Lo JC; Sim SK; Chee MW. Sleep reduces false memory in healthy older adults. SLEEP 2014;37(4):665-671. PMID:24744453

To boost or to CRUNCH? Effect of effortful encoding on episodic memory in older adults is dependent on executive functioning

PubMed Central

Fu, Li; Maes, Joseph H. R.; Kessels, Roy P. C.; Daselaar, Sander M.

2017-01-01

It is essential to develop effective interventions aimed at ameliorating age-related cognitive decline. Previous studies found that effortful encoding benefits episodic memory in older adults. However, to date it is unclear whether this benefit is different for individuals with strong versus weak executive functioning (EF). Fifty-one older adults were recruited and divided into low (N = 26) and high (N = 25) functioning groups, based on their EF capacity. All participants performed a semantic and a perceptual incidental encoding task. Each encoding task was performed under four difficulty levels to establish different effort levels. Encoding was followed by a recognition task. Results showed that the high EF group benefitted from increased effort in both tasks. However, the low EF group only showed a beneficial effect under low levels of effort. Results are consistent with the Compensation-Related Utilization of Neural Circuits Hypothesis (CRUNCH) and suggest that future research directed at developing efficient memory strategies to reduce negative cognitive aging effects should take individual cognitive differences among older adults into account, such as differences in EF. PMID:28328979

Effects of aging and divided attention on episodic feeling-of-knowing accuracy.

PubMed

Sacher, Mathilde; Isingrini, Michel; Taconnat, Laurence

2013-10-01

This research investigated the effect of aging on episodic feeling-of-knowing (FOK) using a divided attention (DA) paradigm in order to examine whether DA in younger adults mimics the effects of aging when decreasing either memory encoding or monitoring processes. To that end, four groups of participants were tested on the FOK task: young adults (control group), young adults under DA at encoding, young adults under DA when making FOK judgments, and older adults. Our results showed that DA at encoding in young adults mimicked the effect of aging on memory performance, and also on FOK magnitude and accuracy, supporting the memory-constraint hypothesis (Hertzog et al., 2010). However, our results do not completely contradict the monitoring-deficit hypothesis, as DA during FOK judgments also affected FOK accuracy, but to a lesser extent than the aging effect or DA during encoding. We suggest that the age-related FOK deficit may be due to a lower level of deep encoding, leading to difficulty retrieving target-related contextual details enabling accurate prediction of subsequent recognition. © 2013.

Neuroanatomical and Cognitive Mediators of Age-Related Differences in Episodic Memory

PubMed Central

Head, Denise; Rodrigue, Karen M.; Kennedy, Kristen M.; Raz, Naftali

2009-01-01

Aging is associated with declines in episodic memory. In this study, the authors used a path analysis framework to explore the mediating role of differences in brain structure, executive functions, and processing speed in age-related differences in episodic memory. Measures of regional brain volume (prefrontal gray and white matter, caudate, hippocampus, visual cortex), executive functions (working memory, inhibitory control, task switching, temporal processing), processing speed, and episodic memory were obtained in a sample of young and older adults. As expected, age was linked to reduction in regional brain volumes and cognitive performance. Moreover, neural and cognitive factors completely mediated age differences in episodic memory. Whereas hippocampal shrinkage directly affected episodic memory, prefrontal volumetric reductions influenced episodic memory via limitations in working memory and inhibitory control. Age-related slowing predicted reduced efficiency in temporal processing, working memory, and inhibitory control. Lastly, poorer temporal processing directly affected episodic memory. No direct effects of age on episodic memory remained once these factors were taken into account. These analyses highlight the value of a multivariate approach with the understanding of complex relationships in cognitive and brain aging. PMID:18590361

Environmental context effects on episodic memory are dependent on retrieval mode and modulated by neuropsychological status.

PubMed

Barak, Ohr; Vakil, Eli; Levy, Daniel A

2013-01-01

Contextual change or constancy between occasions of memory formation and retrieval are commonly assumed to affect retrieval success, yet such effects may be inconsistent, and the processes leading to the pattern of effects are still not well understood. We conducted a systematic investigation of environmental context effects on memory, using a range of materials (common objects, pictures of familiar and unfamiliar faces, words, and sentences), and four types of retrieval (free recall, cued recall, recognition, and order memory), all assessed within participants. Additionally, we examined the influence of mnemonic challenge on context effects by examining both healthy participants and a group of patients in rehabilitation following traumatic brain injury (TBI). We found no effects of contextual factors on tests of recognition for either group of participants, but effects did emerge for cued and free recall, with the most prominent effects being on memory for objects. Furthermore, while patients' memory abilities in general were impaired relative to the comparison group, they exhibited greater influences of contextual reinstatement on several recall tasks. These results support suggestions that environmental context effects on memory are dependent on retrieval mode and on the extent to which retrieval is challenging because of neurocognitive status. Additionally, findings of environmental context effects in memory-impaired TBI patients suggest that by harnessing such preserved indirect memory (e.g., using reminder technologies), it may be possible to ameliorate TBI patients' difficulties in explicit remembering.

Virtual vision system with actual flavor by olfactory display

NASA Astrophysics Data System (ADS)

Sakamoto, Kunio; Kanazawa, Fumihiro

2010-11-01

The authors have researched multimedia system and support system for nursing studies on and practices of reminiscence therapy and life review therapy. The concept of the life review is presented by Butler in 1963. The process of thinking back on one's life and communicating about one's life to another person is called life review. There is a famous episode concerning the memory. It is called as Proustian effects. This effect is mentioned on the Proust's novel as an episode that a story teller reminds his old memory when he dipped a madeleine in tea. So many scientists research why smells trigger the memory. The authors pay attention to the relation between smells and memory although the reason is not evident yet. Then we have tried to add an olfactory display to the multimedia system so that the smells become a trigger of reminding buried memories. An olfactory display is a device that delivers smells to the nose. It provides us with special effects, for example to emit smell as if you were there or to give a trigger for reminding us of memories. The authors have developed a tabletop display system connected with the olfactory display. For delivering a flavor to user's nose, the system needs to recognition and measure positions of user's face and nose. In this paper, the authors describe an olfactory display which enables to detect the nose position for an effective delivery.

Episodic and Semantic Memory Contribute to Familiar and Novel Episodic Future Thinking.

PubMed

Wang, Tong; Yue, Tong; Huang, Xi Ting

2016-01-01

Increasing evidence indicates that episodic future thinking (EFT) relies on both episodic and semantic memory; however, event familiarity may importantly affect the extent to which episodic and semantic memory contribute to EFT. To test this possibility, two behavioral experiments were conducted. In Experiment 1, we directly compared the proportion of episodic and semantic memory used in an EFT task. The results indicated that more episodic memory was used when imagining familiar future events compared with novel future events. Conversely, significantly more semantic memory was used when imagining novel events compared with familiar events. Experiment 2 aimed to verify the results of Experiment 1. In Experiment 2, we found that familiarity moderated the effect of priming the episodic memory system on EFT; particularly, it increased the time required to construct a standard familiar episodic future event, but did not significantly affect novel episodic event reaction time. Collectively, these findings support the hypothesis that event familiarity importantly moderates episodic and semantic memory's contribution to EFT.

ERP Subsequent Memory Effects Differ between Inter-Item and Unitization Encoding Tasks

PubMed Central

Kamp, Siri-Maria; Bader, Regine; Mecklinger, Axel

2017-01-01

The “subsequent memory paradigm” is an analysis tool to identify brain activity elicited during episodic encoding that is associated with successful subsequent retrieval. Two commonly observed event-related potential “subsequent memory effects” (SMEs) are the parietal SME in the P300 time window and the frontal slow wave SME, but to date a clear characterization of the circumstances under which each SME is observed is missing. To test the hypothesis that the parietal SME occurs when aspects of an experience are unitized into a single item representation, while inter-item associative encoding is reflected in the frontal slow wave effect, participants were assigned to one of two conditions that emphasized one of the encoding types under otherwise matched study phases of a recognition memory experiment. Word pairs were presented either in the context of a definition that allowed to combine the word pairs into a new concept (unitization or item encoding) or together with a sentence frame (inter-item encoding). Performance on the recognition test did not differ between the groups. The parietal SME was only found in the definition group, supporting the idea that this SME occurs when the components of an association are integrated in a unitized item representation. An early prefrontal negativity also exhibited an SME only in this group, suggesting that the formation of novel units occurs through interactions of multiple brain areas. The frontal slow wave SME was pronounced in both groups and may thus reflect processes generally involved in encoding of associations. Our results provide evidence for a partial dissociation of the eliciting conditions of the two types of SMEs and therefore provide a tool for future studies to characterize the different types of episodic encoding. PMID:28194105

ERP Subsequent Memory Effects Differ between Inter-Item and Unitization Encoding Tasks.

PubMed

Kamp, Siri-Maria; Bader, Regine; Mecklinger, Axel

2017-01-01

The "subsequent memory paradigm" is an analysis tool to identify brain activity elicited during episodic encoding that is associated with successful subsequent retrieval. Two commonly observed event-related potential "subsequent memory effects" (SMEs) are the parietal SME in the P300 time window and the frontal slow wave SME, but to date a clear characterization of the circumstances under which each SME is observed is missing. To test the hypothesis that the parietal SME occurs when aspects of an experience are unitized into a single item representation, while inter-item associative encoding is reflected in the frontal slow wave effect, participants were assigned to one of two conditions that emphasized one of the encoding types under otherwise matched study phases of a recognition memory experiment. Word pairs were presented either in the context of a definition that allowed to combine the word pairs into a new concept (unitization or item encoding) or together with a sentence frame (inter-item encoding). Performance on the recognition test did not differ between the groups. The parietal SME was only found in the definition group, supporting the idea that this SME occurs when the components of an association are integrated in a unitized item representation. An early prefrontal negativity also exhibited an SME only in this group, suggesting that the formation of novel units occurs through interactions of multiple brain areas. The frontal slow wave SME was pronounced in both groups and may thus reflect processes generally involved in encoding of associations. Our results provide evidence for a partial dissociation of the eliciting conditions of the two types of SMEs and therefore provide a tool for future studies to characterize the different types of episodic encoding.

Functional and Neuroanatomical Specificity of Episodic Memory Dysfunction in Schizophrenia: An fMRI study of the Relational and Item-Specific Encoding Task

PubMed Central

Ragland, J. Daniel; Ranganath, Charan; Harms, Michael P.; Barch, Deanna M.; Gold, James M.; Layher, Evan; Lesh, Tyler A.; MacDonald, Angus W.; Niendam, Tara A.; Phillips, Joshua; Silverstein, Steven M.; Yonelinas, Andrew P.; Carter, Cameron S.

2015-01-01

Importance Individuals with schizophrenia (SZ) can encode item-specific information to support familiarity-based recognition, but are disproportionately impaired encoding inter-item relationships (relational encoding) and recollecting information. The Relational and Item-Specific Encoding (RiSE) paradigm has been used to disentangle these encoding and retrieval processes, which may be dependent on specific medial temporal lobe (MTL) and prefrontal cortex (PFC) subregions. Functional imaging during RiSE task performance could help to specify dysfunctional neural circuits in SZ that can be targeted for interventions to improve memory and functioning in the illness. Objectives To use functional magnetic resonance imaging (fMRI) to test the hypothesis that SZ disproportionately affects MTL and PFC subregions during relational encoding and retrieval, relative to item-specific memory processes. Imaging results from healthy comparison subjects (HC) will also be used to establish neural construct validity for RiSE. Design, Setting, and Participants This multi-site, case-control, cross-sectional fMRI study was conducted at five CNTRACS sites. The final sample included 52 clinically stable outpatients with SZ, and 57 demographically matched HC. Main Outcomes and Measures Behavioral performance speed and accuracy (d’) on item recognition and associative recognition tasks. Voxelwise statistical parametric maps for a priori MTL and PFC regions of interest (ROI), testing activation differences between relational and item-specific memory during encoding and retrieval. Results Item recognition was disproportionately impaired in SZ patients relative to controls following relational encoding. The differential deficit was accompanied by reduced dorsolateral prefrontal cortex (DLPFC) activation during relational encoding in SZ, relative to HC. Retrieval success (hits > misses) was associated with hippocampal (HI) activation in HC during relational item recognition and associative recognition conditions, and HI activation was specifically reduced in SZ for recognition of relational but not item-specific information. Conclusions In this unique, multi-site fMRI study, HC results supported RiSE construct validity by revealing expected memory effects in PFC and MTL subregions during encoding and retrieval. Comparison of SZ and HC revealed disproportionate memory deficits in SZ for relational versus item-specific information, accompanied by regionally and functionally specific deficits in DLPFC and HI activation. PMID:26200928

Long-term memory following transient global amnesia: an investigation of episodic and semantic memory.

PubMed

Guillery-Girard, B; Quinette, P; Desgranges, B; Piolino, P; Viader, F; de la Sayette, V; Eustache, F

2006-11-01

Several studies noted persistence of memory impairment following an episode of transient global amnesia (TGA) with standard tests. To specify long-term memory impairments in a group of patients selected with stringent criteria. Both retrograde and anterograde memory were investigated in 32 patients 13-67 months after a TGA episode with original tasks encompassing retrograde semantic memory (academic, public and personal knowledge), retrograde episodic memory (autobiographical events) and anterograde episodic memory. Patients had preserved academic and public knowledge. Pathological scores were obtained in personal verbal fluency for the two most recent periods, and patients produced less autobiographical events than controls. However, when they were provided time to detail, memories were as episodic as in controls regardless of their remoteness. Anterograde episodic tasks revealed a mild but significant impairment of the capacity of re-living the condition of encoding, i.e. the moment at which words were presented. Patients who have suffered from an episode of TGA manifest deficits of memory focused on the retrieval of both recent semantic information and episodic memories and especially the capacity of re-living. These deficits may not result from a deterioration of memory per se but rather from difficulties in accessing memories.

Making the case that episodic recollection is attributable to operations occurring at retrieval rather than to content stored in a dedicated subsystem of long-term memory.

PubMed

Klein, Stanley B

2013-01-01

Episodic memory often is conceptualized as a uniquely human system of long-term memory that makes available knowledge accompanied by the temporal and spatial context in which that knowledge was acquired. Retrieval from episodic memory entails a form of first-person subjectivity called autonoetic consciousness that provides a sense that a recollection was something that took place in the experiencer's personal past. In this paper I expand on this definition of episodic memory. Specifically, I suggest that (1) the core features assumed unique to episodic memory are shared by semantic memory, (2) episodic memory cannot be fully understood unless one appreciates that episodic recollection requires the coordinated function of a number of distinct, yet interacting, "enabling" systems. Although these systems-ownership, self, subjective temporality, and agency-are not traditionally viewed as memorial in nature, each is necessary for episodic recollection and jointly they may be sufficient, and (3) the type of subjective awareness provided by episodic recollection (autonoetic) is relational rather than intrinsic-i.e., it can be lost in certain patient populations, thus rendering episodic memory content indistinguishable from the content of semantic long-term memory.

How do episodic and semantic memory contribute to episodic foresight in young children?

PubMed

Martin-Ordas, Gema; Atance, Cristina M; Caza, Julian S

2014-01-01

Humans are able to transcend the present and mentally travel to another time, place, or perspective. Mentally projecting ourselves backwards (i.e., episodic memory) or forwards (i.e., episodic foresight) in time are crucial characteristics of the human memory system. Indeed, over the past few years, episodic memory has been argued to be involved both in our capacity to retrieve our personal past experiences and in our ability to imagine and foresee future scenarios. However, recent theory and findings suggest that semantic memory also plays a significant role in imagining future scenarios. We draw on Tulving's definition of episodic and semantic memory to provide a critical analysis of their role in episodic foresight tasks described in the developmental literature. We conclude by suggesting future directions of research that could further our understanding of how both episodic memory and semantic memory are intimately connected to episodic foresight.

How do episodic and semantic memory contribute to episodic foresight in young children?

PubMed Central

Martin-Ordas, Gema; Atance, Cristina M.; Caza, Julian S.

2014-01-01

Humans are able to transcend the present and mentally travel to another time, place, or perspective. Mentally projecting ourselves backwards (i.e., episodic memory) or forwards (i.e., episodic foresight) in time are crucial characteristics of the human memory system. Indeed, over the past few years, episodic memory has been argued to be involved both in our capacity to retrieve our personal past experiences and in our ability to imagine and foresee future scenarios. However, recent theory and findings suggest that semantic memory also plays a significant role in imagining future scenarios. We draw on Tulving’s definition of episodic and semantic memory to provide a critical analysis of their role in episodic foresight tasks described in the developmental literature. We conclude by suggesting future directions of research that could further our understanding of how both episodic memory and semantic memory are intimately connected to episodic foresight. PMID:25071690

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

PubMed

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.

The effect of childhood bilingualism on episodic and semantic memory tasks.

PubMed

Kormi-Nouri, Reza; Shojaei, Razie-Sadat; Moniri, Sadegheh; Gholami, Ali-Reza; Moradi, Ali-Reza; Akbari-Zardkhaneh, Saeed; Nilsson, Lars-Göran

2008-04-01

Kormi-Nouri, Moniri and Nilsson (2003) demonstrated that Swedish-Persian bilingual children recalled at a higher level than Swedish monolingual children, when they were tested using Swedish materials. The present study was designed to examine the bilingual advantage of children who use different languages in their everyday life but have the same cultural background and live in their communities in the same way as monolingual children. In four experiments, 488 monolingual and bilingual children were compared with regard to episodic and semantic memory tasks. In experiments 1 and 2 there were 144 boys and 144 girls in three school groups (aged 9-10 years, 13-14 years and 16-17 years) and in three language groups (Persian monolingual, Turkish-Persian bilingual, and Kurdish-Persian bilingual). In experiments 3 and 4, there were 200 male students in two school groups (aged 9-10 years and 16-17 years) and in two language groups (Persian monolingual and Turkish-Persian bilingual). In the episodic memory task, children learned sentences (experiments 1-3) and words (Experiment 4). Letter and category fluency tests were used as measures of semantic memory. To change cognitive demands in memory tasks, in Experiment 1, the integration of nouns and verbs within sentences was manipulated by the level of association between verb and noun in each sentence. At retrieval, a recognition test was used. In experiments 2 and 3, the organization between sentences was manipulated at encoding in Experiment 2 and at both encoding and retrieval in Experiment 3 through the use of categories among the objects. At retrieval, free recall or cued recall tests were employed. In Experiment 4, the bilingual children were tested with regard to both their first and their second language. In all four experiments, a positive effect of bilingualism was found on episodic and semantic memory tasks; the effect was more pronounced for older than younger children. The bilingual advantage was not affected by changing cognitive demands or by using first/second language in memory tasks. The present findings support the cross-language interactivity hypothesis of bilingual advantage.

Temporal Clustering and Sequencing in Short-Term Memory and Episodic Memory

ERIC Educational Resources Information Center

Farrell, Simon

2012-01-01

A model of short-term memory and episodic memory is presented, with the core assumptions that (a) people parse their continuous experience into episodic clusters and (b) items are clustered together in memory as episodes by binding information within an episode to a common temporal context. Along with the additional assumption that information…

Metamemory in schizophrenia: retrospective confidence ratings interact with neurocognitive deficits.

PubMed

Eifler, Sarah; Rausch, Franziska; Schirmbeck, Frederike; Veckenstedt, Ruth; Mier, Daniela; Esslinger, Christine; Englisch, Susanne; Meyer-Lindenberg, Andreas; Kirsch, Peter; Zink, Mathias

2015-02-28

Prior studies with schizophrenia patients described a reduced ability to discriminate between correct and false memories in terms of confidence compared to control groups. This metamemory bias has been associated with the emergence and maintenance of delusions. The relation to neuropsychological performance and other clinical dimensions is incompletely understood. In a cross-sectional study, metamemory functioning was explored in 32 schizophrenia patients and 25 healthy controls. Metamemory was assessed using a verbal recognition task combined with retrospective confidence level ratings. Associations of metamemory performance with six neuropsychological domains (executive functioning/problem solving, speed of processing, working memory, verbal and visual learning, and attention/vigilance) and psychopathological measures were analyzed. Results revealed a significantly smaller discrepancy between confidence ratings for correct and incorrect recognitions in the patient group. Furthermore, patients showed significantly lower recognition accuracy in the metamemory task and marked deficits in all neuropsychological domains. Across all participants, metamemory performance significantly correlated with executive functioning and working memory. No associations with delusions were found. This data confirms prior findings of metamemory biases in schizophrenia. Selective neuropsychological abilities seem to be modulating factors of metamemory functioning. Longitudinal studies in at risk mental state and first-episode patients are needed to reveal causal interrelations. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Neural correlates of emotional recognition memory in schizophrenia: effects of valence and arousal.

PubMed

Lakis, Nadia; Jiménez, José A; Mancini-Marïe, Adham; Stip, Emmanuel; Lavoie, Marc E; Mendrek, Adrianna

2011-12-30

Schizophrenia patients are often impaired in their memory for emotional events compared with healthy subjects. Investigations of the neural correlates of emotional memory in schizophrenia patients are scarce in the literature. The present study aimed to compare cerebral activations in schizophrenia patients and healthy controls during memory retrieval of emotional images that varied in both valence and arousal. In a study with functional magnetic resonance imaging, 37 schizophrenia patients were compared with 37 healthy participants while performing a yes/no recognition paradigm with positive, negative (differing in arousal intensity) and neutral images. Schizophrenia patients performed worse than healthy controls in all experimental conditions. They showed less cerebral activation in limbic and prefrontal regions than controls during retrieval of negatively valenced stimuli, but had a similar pattern of brain activation compared with controls during retrieval of positively valenced stimuli (particularly in the high arousal condition) in the cerebellum, temporal lobe and prefrontal cortex. Both groups demonstrated increased brain activations in the high relative to low arousing conditions. Our results suggest atypical brain function during retrieval of negative pictures, but intact functional circuitry of positive affect during episodic memory retrieval in schizophrenia patients. The arousal data revealed that schizophrenia patients closely resemble the control group at both the behavioral and neurofunctional level. 2011 Elsevier Ireland Ltd. All rights reserved.

Rats Remember Items in Context Using Episodic Memory.

PubMed

Panoz-Brown, Danielle; Corbin, Hannah E; Dalecki, Stefan J; Gentry, Meredith; Brotheridge, Sydney; Sluka, Christina M; Wu, Jie-En; Crystal, Jonathon D

2016-10-24

Vivid episodic memories in people have been characterized as the replay of unique events in sequential order [1-3]. Animal models of episodic memory have successfully documented episodic memory of a single event (e.g., [4-8]). However, a fundamental feature of episodic memory in people is that it involves multiple events, and notably, episodic memory impairments in human diseases are not limited to a single event. Critically, it is not known whether animals remember many unique events using episodic memory. Here, we show that rats remember many unique events and the contexts in which the events occurred using episodic memory. We used an olfactory memory assessment in which new (but not old) odors were rewarded using 32 items. Rats were presented with 16 odors in one context and the same odors in a second context. To attain high accuracy, the rats needed to remember item in context because each odor was rewarded as a new item in each context. The demands on item-in-context memory were varied by assessing memory with 2, 3, 5, or 15 unpredictable transitions between contexts, and item-in-context memory survived a 45 min retention interval challenge. When the memory of item in context was put in conflict with non-episodic familiarity cues, rats relied on item in context using episodic memory. Our findings suggest that rats remember multiple unique events and the contexts in which these events occurred using episodic memory and support the view that rats may be used to model fundamental aspects of human cognition. Copyright © 2016 Elsevier Ltd. All rights reserved.

Retrieval monitoring and anosognosia in Alzheimer's disease.

PubMed

Gallo, David A; Chen, Jennifer M; Wiseman, Amy L; Schacter, Daniel L; Budson, Andrew E

2007-09-01

This study explored the relationship between episodic memory and anosognosia (a lack of deficit awareness) among patients with mild Alzheimer's disease (AD). Participants studied words and pictures for subsequent memory tests. Healthy older adults made fewer false recognition errors when trying to remember pictures compared with words, suggesting that the perceptual distinctiveness of picture memories enhanced retrieval monitoring (the distinctiveness heuristic). In contrast, although participants with AD could discriminate between studied and nonstudied items, they had difficulty recollecting the specific presentation formats (words or pictures), and they had limited use of the distinctiveness heuristic. Critically, the demands of the memory test modulated the relationship between memory accuracy and anosognosia. Greater anosognosia was associated with impaired memory accuracy when participants with AD tried to remember words but not when they tried to remember pictures. These data further delineate the retrieval monitoring difficulties among individuals with AD and suggest that anosognosia measures are most likely to correlate with memory tests that require the effortful retrieval of nondistinctive information. (PsycINFO Database Record (c) 2007 APA, all rights reserved).

Long-term semantic representations moderate the effect of attentional refreshing on episodic memory.

PubMed

Loaiza, Vanessa M; Duperreault, Kayla A; Rhodes, Matthew G; McCabe, David P

2015-02-01

The McCabe effect (McCabe, Journal of Memory and Language 58:480-494, 2008) refers to an advantage in episodic memory (EM) retrieval for memoranda studied in complex span versus simple span tasks, particularly for memoranda presented in earlier serial positions. This finding has been attributed to the necessity to refresh memoranda during complex span tasks that, in turn, promotes content-context binding in working memory (WM). Several frameworks have conceptualized WM as being embedded in long-term memory. Thus, refreshing may be less efficient when memoranda are not well-established in long-term semantic memory (SM). To investigate this, we presented words and nonwords in simple and complex span trials in order to manipulate the long-term semantic representations of the memoranda with the requirement to refresh the memoranda during WM. A recognition test was administered that required participants to make a remember-know decision for each memorandum recognized as old. The results replicated the McCabe effect, but only for words, and the beneficial effect of refreshing opportunities was exclusive to recollection. These results extend previous research by indicating that the predictive relationship between WM refreshing and long-term EM is specific to recollection and, furthermore, moderated by representations in long-term SM. This supports the predictions of WM frameworks that espouse the importance of refreshing in content-context binding, but also those that view WM as being an activated subset of and, therefore, constrained by the contents of long-term memory.

Memory Accumulation Mechanisms in Human Cortex Are Independent of Motor Intentions

PubMed Central

Tosoni, Annalisa; Mignogna, Valeria; McAvoy, Mark P.; Shulman, Gordon L.; Corbetta, Maurizio; Romani, Gian Luca

2014-01-01

Previous studies on perceptual decision-making have often emphasized a tight link between decisions and motor intentions. Human decisions, however, also depend on memories or experiences that are not closely tied to specific motor responses. Recent neuroimaging findings have suggested that, during episodic retrieval, parietal activity reflects the accumulation of evidence for memory decisions. It is currently unknown, however, whether these evidence accumulation signals are functionally linked to signals for motor intentions coded in frontoparietal regions and whether activity in the putative memory accumulator tracks the amount of evidence for only previous experience, as reflected in “old” reports, or for both old and new decisions, as reflected in the accuracy of memory judgments. Here, human participants used saccadic-eye and hand-pointing movements to report recognition judgments on pictures defined by different degrees of evidence for old or new decisions. A set of cortical regions, including the middle intraparietal sulcus, showed a monotonic variation of the fMRI BOLD signal that scaled with perceived memory strength (older > newer), compatible with an asymmetrical memory accumulator. Another set, including the hippocampus and the angular gyrus, showed a nonmonotonic response profile tracking memory accuracy (higher > lower evidence), compatible with a symmetrical accumulator. In contrast, eye and hand effector-specific regions in frontoparietal cortex tracked motor intentions but were not modulated by the amount of evidence for the effector outcome. We conclude that item recognition decisions are supported by a combination of symmetrical and asymmetrical accumulation signals largely segregated from motor intentions. PMID:24828652

Hippocampal functional connectivity and episodic memory in early childhood

PubMed Central

Riggins, Tracy; Geng, Fengji; Blankenship, Sarah L.; Redcay, Elizabeth

2016-01-01

Episodic memory relies on a distributed network of brain regions, with the hippocampus playing a critical and irreplaceable role. Few studies have examined how changes in this network contribute to episodic memory development early in life. The present addressed this gap by examining relations between hippocampal functional connectivity and episodic memory in 4-and 6-year-old children (n=40). Results revealed similar hippocampal functional connectivity between age groups, which included lateral temporal regions, precuneus, and multiple parietal and prefrontal regions, and functional specialization along the longitudinal axis. Despite these similarities, developmental differences were also observed. Specifically, 3 (of 4) regions within the hippocampal memory network were positively associated with episodic memory in 6-year-old children, but negatively associated with episodic memory in 4-year-old children. In contrast, all 3 regions outside the hippocampal memory network were negatively associated with episodic memory in older children, but positively associated with episodic memory in younger children. These interactions are interpreted within an interactive specialization framework and suggest the hippocampus becomes functionally integrated with cortical regions that are part of the hippocampal memory network in adults and functionally segregated from regions unrelated to memory in adults, both of which are associated with age-related improvements in episodic memory ability. PMID:26900967

Hippocampal functional connectivity and episodic memory in early childhood.

PubMed

Riggins, Tracy; Geng, Fengji; Blankenship, Sarah L; Redcay, Elizabeth

2016-06-01

Episodic memory relies on a distributed network of brain regions, with the hippocampus playing a critical and irreplaceable role. Few studies have examined how changes in this network contribute to episodic memory development early in life. The present addressed this gap by examining relations between hippocampal functional connectivity and episodic memory in 4- and 6-year-old children (n=40). Results revealed similar hippocampal functional connectivity between age groups, which included lateral temporal regions, precuneus, and multiple parietal and prefrontal regions, and functional specialization along the longitudinal axis. Despite these similarities, developmental differences were also observed. Specifically, 3 (of 4) regions within the hippocampal memory network were positively associated with episodic memory in 6-year-old children, but negatively associated with episodic memory in 4-year-old children. In contrast, all 3 regions outside the hippocampal memory network were negatively associated with episodic memory in older children, but positively associated with episodic memory in younger children. These interactions are interpreted within an interactive specialization framework and suggest the hippocampus becomes functionally integrated with cortical regions that are part of the hippocampal memory network in adults and functionally segregated from regions unrelated to memory in adults, both of which are associated with age-related improvements in episodic memory ability. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Left prefrontal cortex control of novel occurrences during recollection: a psychopharmacological study using scopolamine and event-related fMRI.

PubMed

Bozzali, M; MacPherson, S E; Dolan, R J; Shallice, T

2006-10-15

Recollection and familiarity represent two processes involved in episodic memory retrieval. We investigated how scopolamine (an antagonist of acetylcholine muscarinic receptors) influenced brain activity during memory retrieval, using a paradigm that separated recollection and familiarity. Eighteen healthy volunteers were recruited in a randomized, placebo-controlled, double-blind design using event-related fMRI. Participants were required to perform a verbal recognition memory task within the scanner, either under placebo or scopolamine conditions. Depending on the subcondition, participants were required to make a simple recognition decision (old/new items) or base their decision on more specific information related to prior experience (target/non-target/new items). We show a drug modulation in left prefrontal and perirhinal cortex during recollection. Such an effect was specifically driven by novelty and showed an inverse correlation with accuracy performance. Additionally, we show a direct correlation between drug-related signal change in left prefrontal and perirhinal cortices. We discuss the findings in terms of acetylcholine mediation of the familiarity/novelty signal through perirhinal cortex and the control of the relative signal strength through prefrontal cortex.

Making the case that episodic recollection is attributable to operations occurring at retrieval rather than to content stored in a dedicated subsystem of long-term memory

PubMed Central

Klein, Stanley B.

2013-01-01

Episodic memory often is conceptualized as a uniquely human system of long-term memory that makes available knowledge accompanied by the temporal and spatial context in which that knowledge was acquired. Retrieval from episodic memory entails a form of first–person subjectivity called autonoetic consciousness that provides a sense that a recollection was something that took place in the experiencer's personal past. In this paper I expand on this definition of episodic memory. Specifically, I suggest that (1) the core features assumed unique to episodic memory are shared by semantic memory, (2) episodic memory cannot be fully understood unless one appreciates that episodic recollection requires the coordinated function of a number of distinct, yet interacting, “enabling” systems. Although these systems—ownership, self, subjective temporality, and agency—are not traditionally viewed as memorial in nature, each is necessary for episodic recollection and jointly they may be sufficient, and (3) the type of subjective awareness provided by episodic recollection (autonoetic) is relational rather than intrinsic—i.e., it can be lost in certain patient populations, thus rendering episodic memory content indistinguishable from the content of semantic long-term memory. PMID:23378832

[Neural Mechanisms Underlying the Processing of Temporal Information in Episodic Memory and Its Disturbance].

PubMed

Iwata, Saeko; Tsukiura, Takashi

2017-11-01

Episodic memory is defined as memory for personally experienced events, and includes memory content and contextual information of time and space. Previous neuroimaging and neuropsychological studies have demonstrated three possible roles of the temporal context in episodic memory. First, temporal information contributes to the arrangement of temporal order for sequential events in episodic memory, and this process is involved in the lateral prefrontal cortex. The second possible role of temporal information in episodic memory is the segregation between memories of multiple events, which are segregated by cues of different time information. The role of segregation is associated with the orbitofrontal regions including the orbitofrontal cortex and basal forebrain region. Third, temporal information in episodic memory plays an important role in the integration of multiple components into a coherent episodic memory, in which episodic components in the different modalities are combined by temporal information as an index. The role of integration is mediated by the medial temporal lobe including the hippocampus and parahippocampal gyrus. Thus, temporal information in episodic memory could be represented in multiple stages, which are involved in a network of the lateral prefrontal, orbitofrontal, and medial temporal lobe regions.

Episodic memory, semantic memory, and amnesia.

PubMed

Squire, L R; Zola, S M

1998-01-01

Episodic memory and semantic memory are two types of declarative memory. There have been two principal views about how this distinction might be reflected in the organization of memory functions in the brain. One view, that episodic memory and semantic memory are both dependent on the integrity of medial temporal lobe and midline diencephalic structures, predicts that amnesic patients with medial temporal lobe/diencephalic damage should be proportionately impaired in both episodic and semantic memory. An alternative view is that the capacity for semantic memory is spared, or partially spared, in amnesia relative to episodic memory ability. This article reviews two kinds of relevant data: 1) case studies where amnesia has occurred early in childhood, before much of an individual's semantic knowledge has been acquired, and 2) experimental studies with amnesic patients of fact and event learning, remembering and knowing, and remote memory. The data provide no compelling support for the view that episodic and semantic memory are affected differently in medial temporal lobe/diencephalic amnesia. However, episodic and semantic memory may be dissociable in those amnesic patients who additionally have severe frontal lobe damage.

Catechol-O-methyltransferase Val(158)Met association with parahippocampal physiology during memory encoding in schizophrenia.

PubMed

Di Giorgio, A; Caforio, G; Blasi, G; Taurisano, P; Fazio, L; Romano, R; Ursini, G; Gelao, B; Bianco, L Lo; Papazacharias, A; Sinibaldi, L; Popolizio, T; Bellomo, A; Bertolino, A

2011-08-01

Catechol-O-methyltransferase (COMT) Val158Met has been associated with activity of the mesial temporal lobe during episodic memory and it may weakly increase risk for schizophrenia. However, how this variant affects parahippocampal and hippocampal physiology when dopamine transmission is perturbed is unclear. The aim of the present study was to compare the effects of the COMT Val158Met genotype on parahippocampal and hippocampal physiology during encoding of recognition memory in patients with schizophrenia and in healthy subjects. Using blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI), we studied 28 patients with schizophrenia and 33 healthy subjects matched for a series of sociodemographic and genetic variables while they performed a recognition memory task. We found that healthy subjects had greater parahippocampal and hippocampal activity during memory encoding compared to patients with schizophrenia. We also found different activity of the parahippocampal region between healthy subjects and patients with schizophrenia as a function of the COMT genotype, in that the predicted COMT Met allele dose effect had an opposite direction in controls and patients. Our results demonstrate a COMT Val158Met genotype by diagnosis interaction in parahippocampal activity during memory encoding and may suggest that modulation of dopamine signaling interacts with other disease-related processes in determining the phenotype of parahippocampal physiology in schizophrenia. © Cambridge University Press 2010

Medial temporal lobe function during emotional memory in early Alzheimer's disease, mild cognitive impairment and healthy ageing: an fMRI study.

PubMed

Parra, Mario A; Pattan, Vivek; Wong, Dichelle; Beaglehole, Anna; Lonie, Jane; Wan, Hong I; Honey, Garry; Hall, Jeremy; Whalley, Heather C; Lawrie, Stephen M

2013-03-06

Relative to intentional memory encoding, which quickly declines in Mild Cognitive Impairment (MCI) and Alzheimer's disease (AD), incidental memory for emotional stimuli appears to deteriorate more slowly. We hypothesised that tests of incidental emotional memory may inform on different aspects of cognitive decline in MCI and AD. Patients with MCI, AD and Healthy Controls (HC) were asked to attend to emotional pictures (i.e., positive and neutral) sequentially presented during an fMRI session. Attention was monitored behaviourally. A surprise post-scan recognition test was then administered. The groups remained attentive within the scanner. The post-scan recognition pattern was in the form of (HC = MCI) > AD, with only the former group showing a clear benefit from emotional pictures. fMRI analysis of incidental encoding demonstrated clusters of activation in para-hippocampal regions and in the hippocampus in HC and MCI patients but not in AD patients. The pattern of activation observed in MCI patients tended to be greater than that found in HC. The results suggest that incidental emotional memory might offer a suitable platform to investigate, using behavioural and fMRI measures, subtle changes in the process of developing AD. These changes seem to differ from those found using standard episodic memory tests. The underpinnings of such differences and the potential clinical use of this methodology are discussed in depth.

The development of control processes supporting source memory discrimination as revealed by event-related potentials.

PubMed

de Chastelaine, Marianne; Friedman, David; Cycowicz, Yael M

2007-08-01

Improvement in source memory performance throughout childhood is thought to be mediated by the development of executive control. As postretrieval control processes may be better time-locked to the recognition response rather than the retrieval cue, the development of processes underlying source memory was investigated with both stimulus- and response-locked event-related potentials (ERPs). These were recorded in children, adolescents, and adults during a recognition memory exclusion task. Green- and red-outlined pictures were studied, but were tested in black outline. The test requirement was to endorse old items shown in one study color ("targets") and to reject new items along with old items shown in the alternative study color ("nontargets"). Source memory improved with age. All age groups retrieved target and nontarget memories as reflected by reliable parietal episodic memory (EM) effects, a stimulus-locked ERP correlate of recollection. Response-locked ERPs to targets and nontargets diverged in all groups prior to the response, although this occurred at an increasingly earlier time point with age. We suggest these findings reflect the implementation of attentional control mechanisms to enhance target memories and facilitate response selection with the greatest and least success, respectively, in adults and children. In adults only, response-locked ERPs revealed an early-onsetting parietal negativity for nontargets, but not for targets. This was suggested to reflect adults' ability to consistently inhibit prepotent target responses for nontargets. The findings support the notion that the development of source memory relies on the maturation of control processes that serve to enhance accurate selection of task-relevant memories.

Changes in Tryptophan Catabolite (TRYCAT) Pathway Patterning Are Associated with Mild Impairments in Declarative Memory in Schizophrenia and Deficits in Semantic and Episodic Memory Coupled with Increased False-Memory Creation in Deficit Schizophrenia.

PubMed

Kanchanatawan, Buranee; Hemrungrojn, Solaphat; Thika, Supaksorn; Sirivichayakul, Sunee; Ruxrungtham, Kiat; Carvalho, André F; Geffard, Michel; Anderson, George; Maes, Michael

2018-06-01

Evidence indicates that schizophrenia and in particular negative symptoms and deficit schizophrenia are accompanied by neurocognitive impairments and changes in the patterning of the tryptophan catabolite (TRYCAT) pathway. This cross-sectional study was carried out to examine the associations between cognitive functions (as measured with Consortium to Establish a Registry for Alzheimer's disease (CERAD)) and TRYCAT pathway patterning in patients with (n = 40) and without (n = 40) deficit schizophrenia and normal controls (n = 40). Cognitive measures were assessed with the Verbal Fluency Test (VFT), Boston Naming Test (BNT), Mini-Mental State Examination (MMSE), Word List Memory (WLM), Constructional Praxis, Word List Recall (WLRecall), and Word List Recognition (WLRecognition), while TRYCAT measurements assessed the IgA/IgM responses to noxious TRYCATs, namely quinolinic acid (QA), 3-OH-kynurenine (3HK), picolinic acid (PA), and xanthurenic (XA) acid, and more protective (PRO) TRYCATs, including kynurenic acid (KA) and anthranilic acid (AA). IgA NOX/PRO, IgM KA/3HK, and IgA/IgM NOX/PRO ratios were computed. Schizophrenia was accompanied by lower VFT and WLM, while BNT (dysnomia) and MMSE are significantly lower in multiple- than first-episode schizophrenia. Deficit schizophrenia is strongly associated with worse outcomes on VFT, MMSE, WLM, WLRecall, WLRecognition, and delayed recall savings and increased false memories. Around 40-50% of the variance in negative symptoms' scores was explained by VFT, WLM, WLRecall, and MMSE. Increases in IgA NOX/PRO, IgM KA/3HK, and/or IgA/IgM NOX/PRO ratios were associated with impairments in VFT, BNT, MMSE, WLM, WLRecall, WLRecognition, and false-memory creation. In conclusion, nondeficit schizophrenia is accompanied by mild memory impairments, while disease progression is accompanied by broader cognitive impairments. Deficit schizophrenia and negative symptoms are strongly associated with deficits in working memory, delayed recall and recognition, and increased false-memory creation. These cognitive impairments and memory deficits are in part explained by increased production and/or attenuated regulation of TRYCATs with neurotoxic, excitotoxic, immune-inflammatory, oxidative, and nitrosative potential, which may contribute to neuroprogression.

The Composition of Episodic Memory.

ERIC Educational Resources Information Center

Underwood, Benton J.; And Others

This study examined the interrelationships among a number of episodic memory tasks and among various attributes of memory. A sample of 200 college students was tested for ten sessions; 28 different measures of episodic memory were obtained. In addition, five measures of semantic memory were available. Results indicated that episodic and semantic…

Episodic and semantic memory in children with mesial temporal sclerosis.

PubMed

Rzezak, Patricia; Guimarães, Catarina; Fuentes, Daniel; Guerreiro, Marilisa M; Valente, Kette Dualibi Ramos

2011-07-01

The aim of this study was to analyze semantic and episodic memory deficits in children with mesial temporal sclerosis (MTS) and their correlation with clinical epilepsy variables. For this purpose, 19 consecutive children and adolescents with MTS (8 to 16 years old) were evaluated and their performance on five episodic memory tests (short- and long-term memory and learning) and four semantic memory tests was compared with that of 28 healthy volunteers. Patients performed worse on tests of immediate and delayed verbal episodic memory, visual episodic memory, verbal and visual learning, mental scanning for semantic clues, object naming, word definition, and repetition of sentences. Clinical variables such as early age at seizure onset, severity of epilepsy, and polytherapy impaired distinct types of memory. These data confirm that children with MTS have episodic memory deficits and add new information on semantic memory. The data also demonstrate that clinical variables contribute differently to episodic and semantic memory performance. Copyright © 2011 Elsevier Inc. All rights reserved.

Episodic memory impairment in systemic lupus erythematosus: involvement of thalamic structures.

PubMed

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

2015-02-01

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

Contextualization: Memory Formation and Retrieval in a Nested Environment

NASA Astrophysics Data System (ADS)

Piefke, Martina; Markowitsch, Hans J.

Episodic memory functions are highly context-dependent. This is true for both experimental and autobiographical episodic memory. We here review neuropsychological and neuroimaging evidence for effects of differential encoding and retrieval contexts on episodic memory performance as well as the underlying neurofunctional mechanisms. In studies of laboratory episodic memory, the influence of context parameters can be assessed by experimental manipulations. Such experiments suggest that contextual variables mainly affect prefrontal functions supporting executive processes involved in episodic learning and retrieval. Context parameters affecting episodic autobiographical memory are far more complex and cannot easily be controlled. Data support the view that not only prefrontal, but also further medial temporal and posterior parietal regions mediating the re-experience and emotional evaluation of personal memories are highly influenced by changing contextual variables of memory encoding and retrieval. Based on our review of available data, we thus suggest that experimental and autobiographical episodic memories are influenced by both overlapping and differential context parameters.

Effects of perceptual similarity but not semantic association on false recognition in aging

PubMed Central

Gill, Emma

2017-01-01

This study investigated semantic and perceptual influences on false recognition in older and young adults in a variant on the Deese-Roediger-McDermott paradigm. In two experiments, participants encoded intermixed sets of semantically associated words, and sets of unrelated words. Each set was presented in a shared distinctive font. Older adults were no more likely to falsely recognize semantically associated lure words compared to unrelated lures also presented in studied fonts. However, they showed an increase in false recognition of lures which were related to studied items only by a shared font. This increased false recognition was associated with recollective experience. The data show that older adults do not always rely more on prior knowledge in episodic memory tasks. They converge with other findings suggesting that older adults may also be more prone to perceptually-driven errors. PMID:29302398

Looking for episodic memory in animals and young children: prospects for a new minimalism.

PubMed

Clayton, Nicola S; Russell, James

2009-09-01

Because animals and young children cannot be interrogated about their experiences it is difficult to conduct research into their episodic memories. The approach to this issue adopted by Clayton and Dickinson [Clayton, N. S., & Dickinson, A. (1998). Episodic-like memory during cache recovery by scrub jays. Nature, 395, 272-274] was to take a conceptually minimalist definition of episodic memory, in terms of integrating information about what was done where and when [Tulving, E. (1972). Episodic and semantic memory. In E. Tulving, & W. Donaldson (Eds.), Organisation of memory (pp. 381-403). New York: Academic Press], and to refer to such memories as 'episodic-like'. Some claim, however, that because animals supposedly lack the conceptual abilities necessary for episodic recall one should properly call these memories 'semantic'. We address this debate with a novel approach to episodic memory, which is minimalist insofar as it focuses on the non-conceptual content of a re-experienced situation. It rests on Kantian assumptions about the necessary 'perspectival' features of any objective experience or re-experience. We show how adopting this perspectival approach can render an episodic interpretation of the animal data more plausible and can also reveal patterns in the mosaic of developmental evidence for episodic memory in humans.

Semantic and episodic memory in children with temporal lobe epilepsy: do they relate to literacy skills?

PubMed

Lah, Suncica; Smith, Mary Lou

2014-01-01

Children with temporal lobe epilepsy are at risk for deficits in new learning (episodic memory) and literacy skills. Semantic memory deficits and double dissociations between episodic and semantic memory have recently been found in this patient population. In the current study we investigate whether impairments of these 2 distinct memory systems relate to literacy skills. 57 children with unilateral temporal lobe epilepsy completed tests of verbal memory (episodic and semantic) and literacy skills (reading and spelling accuracy, and reading comprehension). For the entire group, semantic memory explained over 30% of variance in each of the literacy domains. Episodic memory explained a significant, but rather small proportion (< 10%) of variance in reading and spelling accuracy, but not in reading comprehension. Moreover, when children with opposite patterns of specific memory impairments (intact semantic/impaired episodic, intact episodic/impaired semantic) were compared, significant reductions in literacy skills were evident only in children with semantic memory impairments, but not in children with episodic memory impairments relative to the norms and to children with temporal lobe epilepsy who had intact memory. Our study provides the first evidence for differential relations between episodic and semantic memory impairments and literacy skills in children with temporal lobe epilepsy. As such, it highlights the urgent need to consider semantic memory deficits in management of children with temporal lobe epilepsy and undertake further research into the nature of reading difficulties of children with semantic memory impairments.

Analogous selection processes in declarative and procedural working memory: N-2 list-repetition and task-repetition costs.

PubMed

Gade, Miriam; Souza, Alessandra S; Druey, Michel D; Oberauer, Klaus

2017-01-01

Working memory (WM) holds and manipulates representations for ongoing cognition. Oberauer (Psychology of Learning and Motivation, 51, 45-100, 2009) distinguishes between two analogous WM sub-systems: a declarative WM which handles the objects of thought, and a procedural WM which handles the representations of (cognitive) actions. Here, we assessed whether analogous effects are observed when participants switch between memory sets (declarative representations) and when they switch between task sets (procedural representations). One mechanism assumed to facilitate switching in procedural WM is the inhibition of previously used, but currently irrelevant task sets, as indexed by n-2 task-repetition costs (Mayr & Keele, Journal of Experimental Psychology: General, 129(1), 4-26, 2000). In this study we tested for an analogous effect in declarative WM. We assessed the evidence for n-2 list-repetition costs across eight experiments in which participants switched between memory lists to perform speeded classifications, mental arithmetic, or a local recognition test. N-2 list-repetition costs were obtained consistently in conditions assumed to increase interference between memory lists, and when lists formed chunks in long-term memory. Further analyses across experiments revealed a substantial contribution of episodic memory to n-2 list-repetition costs, thereby questioning the interpretation of n-2 repetition costs as reflecting inhibition. We reanalyzed the data of eight task-switching experiments, and observed that episodic memory also contributes to n-2 task-repetition costs. Taken together, these results show analogous processing principles in declarative and procedural WM, and question the relevance of inhibitory processes for efficient switching between mental sets.

No Sensory Compensation for Olfactory Memory: Differences between Blind and Sighted People.

PubMed

Sorokowska, Agnieszka; Karwowski, Maciej

2017-01-01

Blindness can be a driving force behind a variety of changes in sensory systems. When vision is missing, other modalities and higher cognitive functions can become hyper-developed through a mechanism called sensory compensation. Overall, previous studies suggest that olfactory memory in blind people can be better than that of the sighted individuals. Better performance of blind individuals in other-sensory modalities was hypothesized to be a result of, among others, intense perceptual training. At the same time, if the superiority of blind people in olfactory abilities indeed results from training, their scores should not decrease with age to such an extent as among the sighted people. Here, this hypothesis was tested in a large sample of 94 blind individuals. Olfactory memory was assessed using the Test for Olfactory Memory, comprising episodic odor recognition (discriminating previously presented odors from new odors) and two forms of semantic memory (cued and free identification of odors). Regarding episodic olfactory memory, we observed an age-related decline in correct hits in blind participants, but an age-related increase in false alarms in sighted participants. Further, age moderated the between-group differences for correct hits, but the direction of the observed effect was contrary to our expectations. The difference between blind and sighted individuals younger than 40 years old was non-significant, but older sighted individuals outperformed their blind counterparts. In conclusion, we found no positive effect of visual impairment on olfactory memory. We suggest that daily perceptual training is not enough to increase olfactory memory function in blind people.

No Sensory Compensation for Olfactory Memory: Differences between Blind and Sighted People

PubMed Central

Sorokowska, Agnieszka; Karwowski, Maciej

2017-01-01

Blindness can be a driving force behind a variety of changes in sensory systems. When vision is missing, other modalities and higher cognitive functions can become hyper-developed through a mechanism called sensory compensation. Overall, previous studies suggest that olfactory memory in blind people can be better than that of the sighted individuals. Better performance of blind individuals in other-sensory modalities was hypothesized to be a result of, among others, intense perceptual training. At the same time, if the superiority of blind people in olfactory abilities indeed results from training, their scores should not decrease with age to such an extent as among the sighted people. Here, this hypothesis was tested in a large sample of 94 blind individuals. Olfactory memory was assessed using the Test for Olfactory Memory, comprising episodic odor recognition (discriminating previously presented odors from new odors) and two forms of semantic memory (cued and free identification of odors). Regarding episodic olfactory memory, we observed an age-related decline in correct hits in blind participants, but an age-related increase in false alarms in sighted participants. Further, age moderated the between-group differences for correct hits, but the direction of the observed effect was contrary to our expectations. The difference between blind and sighted individuals younger than 40 years old was non-significant, but older sighted individuals outperformed their blind counterparts. In conclusion, we found no positive effect of visual impairment on olfactory memory. We suggest that daily perceptual training is not enough to increase olfactory memory function in blind people. PMID:29276494

Episodic and working memory deficits in alcoholic Korsakoff patients: the continuity theory revisited.

PubMed

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

2008-07-01

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

Constructing realistic engrams: poststimulus activity of hippocampus and dorsal striatum predicts subsequent episodic memory.

PubMed

Ben-Yakov, Aya; Dudai, Yadin

2011-06-15

Encoding of real-life episodic memory commonly involves integration of information as the episode unfolds. Offline processing immediately following event offset is expected to play a role in encoding the episode into memory. In this study, we examined whether distinct human brain activity time-locked to the offset of short narrative audiovisual episodes could predict subsequent memory for the gist of the episodes. We found that a set of brain regions, most prominently the bilateral hippocampus and the bilateral caudate nucleus, exhibit memory-predictive activity time-locked to the stimulus offset. We propose that offline activity in these regions reflects registration to memory of integrated episodes.

The medial temporal lobes distinguish between within-item and item-context relations during autobiographical memory retrieval.

PubMed

Sheldon, Signy; Levine, Brian

2015-12-01

During autobiographical memory retrieval, the medial temporal lobes (MTL) relate together multiple event elements, including object (within-item relations) and context (item-context relations) information, to create a cohesive memory. There is consistent support for a functional specialization within the MTL according to these relational processes, much of which comes from recognition memory experiments. In this study, we compared brain activation patterns associated with retrieving within-item relations (i.e., associating conceptual and sensory-perceptual object features) and item-context relations (i.e., spatial relations among objects) with respect to naturalistic autobiographical retrieval. We developed a novel paradigm that cued participants to retrieve information about past autobiographical events, non-episodic within-item relations, and non-episodic item-context relations with the perceptuomotor aspects of retrieval equated across these conditions. We used multivariate analysis techniques to extract common and distinct patterns of activity among these conditions within the MTL and across the whole brain, both in terms of spatial and temporal patterns of activity. The anterior MTL (perirhinal cortex and anterior hippocampus) was preferentially recruited for generating within-item relations later in retrieval whereas the posterior MTL (posterior parahippocampal cortex and posterior hippocampus) was preferentially recruited for generating item-context relations across the retrieval phase. These findings provide novel evidence for functional specialization within the MTL with respect to naturalistic memory retrieval. © 2015 Wiley Periodicals, Inc.

Self-referencing enhances recollection in both young and older adults

PubMed Central

Leshikar, Eric D.; Dulas, Michael R.; Duarte, Audrey

2014-01-01

Processing information in relation to the self enhances subsequent item recognition in both young and older adults, and further, enhances recollection at least in the young. Because older adults experience recollection memory deficits it is unknown whether self-referencing improves recollection in older adults. We examined recollection benefits from self-referential encoding in older and younger adults and further examined the quality and quantity of episodic details facilitated by self-referencing. We further investigated the influence of valence on recollection given prior findings of age group differences in emotional memory (i.e. “positivity effects”). Across 2 experiments, young and older adults processed positive and negative adjectives either for self-relevance or for semantic meaning. We found that self-referencing, relative to semantic encoding, increased recollection memory in both age groups. In Experiment 1, both groups remembered proportionally more negative than positive items when adjectives were processed semantically; however, when adjectives were processed self-referentially, both groups exhibited evidence of better recollection for the positive items, inconsistent with a positivity effect in aging. In Experiment 2, both groups reported more episodic details associated with recollected items, as measured by a memory characteristic questionnaire (MCQ), for the self-reference relative to the semantic condition. Overall, these data suggest that self-referencing leads to detail-rich memory representations reflected in higher rates of recollection across age. PMID:25264018

Older and Wiser: Older Adults’ Episodic Word Memory Benefits from Sentence Study Contexts

PubMed Central

Matzen, Laura E.; Benjamin, Aaron S.

2013-01-01

A hallmark of adaptive cognition is the ability to modulate learning in response to the demands posed by different types of tests and different types of materials. Here we evaluate how older adults process words and sentences differently by examining patterns of memory errors. In two experiments, we explored younger and older adults’ sensitivity to lures on a recognition test following study of words in these two types of contexts. Among the studied words were compound words such as “blackmail” and “jailbird” that were related to conjunction lures (e.g. “blackbird”) and semantic lures (e.g. “criminal”). Participants engaged in a recognition test that included old items, conjunction lures, semantic lures, and unrelated new items. In both experiments, younger and older adults had the same general pattern of memory errors: more incorrect endorsements of semantic than conjunction lures following sentence study and more incorrect endorsements of conjunction than semantic lures following list study. The similar pattern reveals that older and younger adults responded to the constraints of the two different study contexts in similar ways. However, while younger and older adults showed similar levels of memory performance for the list study context, the sentence study context elicited superior memory performance in the older participants. It appears as though memory tasks that take advantage of greater expertise in older adults--in this case, greater experience with sentence processing--can reveal superior memory performance in the elderly. PMID:23834493

A Randomized, Double-Blinded, Placebo-Controlled Study to Compare the Safety and Efficacy of Low Dose Enhanced Wild Blueberry Powder and Wild Blueberry Extract (ThinkBlue™) in Maintenance of Episodic and Working Memory in Older Adults.

PubMed

Whyte, Adrian R; Cheng, Nancy; Fromentin, Emilie; Williams, Claire M

2018-05-23

Previous research has shown beneficial effects of polyphenol-rich diets in ameliorating cognitive decline in aging adults. Here, using a randomized, double blinded, placebo-controlled chronic intervention, we investigated the effect of two proprietary blueberry formulations on cognitive performance in older adults; a whole wild blueberry powder at 500 mg (WBP500) and 1000 mg (WBP1000) and a purified extract at 100 mg (WBE111). One hundred and twenty-two older adults (65⁻80 years) were randomly allocated to a 6-month, daily regimen of either placebo or one of the three interventions. Participants were tested at baseline, 3, and 6 months on a battery of cognitive tasks targeting episodic memory, working memory and executive function, alongside mood and cardiovascular health parameters. Linear mixed model analysis found intervention to be a significant predictor of delayed word recognition on the Reys Auditory Verbal Learning Task (RAVLT), with simple contrast analysis revealing significantly better performance following WBE111 at 3 months. Similarly, performance on the Corsi Block task was predicted by treatment, with simple contrast analysis revealing a trend for better performance at 3 months following WBE111. Treatment also significantly predicted systolic blood pressure (SBP) with simple contrast analysis revealing lower SBP following intervention with WBE111 in comparison to placebo. These results indicate 3 months intervention with WBE111 can facilitate better episodic memory performance in an elderly population and reduce cardiovascular risk factors over 6 months.

The reduction of adult neurogenesis in depression impairs the retrieval of new as well as remote episodic memory

PubMed Central

Fang, Jing; Demic, Selver; Cheng, Sen

2018-01-01

Major depressive disorder (MDD) is associated with an impairment of episodic memory, but the mechanisms underlying this deficit remain unclear. Animal models of MDD find impaired adult neurogenesis (AN) in the dentate gyrus (DG), and AN in DG has been suggested to play a critical role in reducing the interference between overlapping memories through pattern separation. Here, we study the effect of reduced AN in MDD on the accuracy of episodic memory using computational modeling. We focus on how memory is affected when periods with a normal rate of AN (asymptomatic states) alternate with periods with a low rate (depressive episodes), which has never been studied before. Also, unlike previous models of adult neurogenesis, which consider memories as static patterns, we model episodic memory as sequences of neural activity patterns. In our model, AN adds additional random components to the memory patterns, which results in the decorrelation of similar patterns. Consistent with previous studies, higher rates of AN lead to higher memory accuracy in our model, which implies that memories stored in the depressive state are impaired. Intriguingly, our model makes the novel prediction that memories stored in an earlier asymptomatic state are also impaired by a later depressive episode. This retrograde effect exacerbates with increased duration of the depressive episode. Finally, pattern separation at the sensory processing stage does not improve, but rather worsens, the accuracy of episodic memory retrieval, suggesting an explanation for why AN is found in brain areas serving memory rather than sensory function. In conclusion, while cognitive retrieval biases might contribute to episodic memory deficits in MDD, our model suggests a mechanistic explanation that affects all episodic memories, regardless of emotional relevance. PMID:29879169

The reduction of adult neurogenesis in depression impairs the retrieval of new as well as remote episodic memory.

PubMed

Fang, Jing; Demic, Selver; Cheng, Sen

2018-01-01

Major depressive disorder (MDD) is associated with an impairment of episodic memory, but the mechanisms underlying this deficit remain unclear. Animal models of MDD find impaired adult neurogenesis (AN) in the dentate gyrus (DG), and AN in DG has been suggested to play a critical role in reducing the interference between overlapping memories through pattern separation. Here, we study the effect of reduced AN in MDD on the accuracy of episodic memory using computational modeling. We focus on how memory is affected when periods with a normal rate of AN (asymptomatic states) alternate with periods with a low rate (depressive episodes), which has never been studied before. Also, unlike previous models of adult neurogenesis, which consider memories as static patterns, we model episodic memory as sequences of neural activity patterns. In our model, AN adds additional random components to the memory patterns, which results in the decorrelation of similar patterns. Consistent with previous studies, higher rates of AN lead to higher memory accuracy in our model, which implies that memories stored in the depressive state are impaired. Intriguingly, our model makes the novel prediction that memories stored in an earlier asymptomatic state are also impaired by a later depressive episode. This retrograde effect exacerbates with increased duration of the depressive episode. Finally, pattern separation at the sensory processing stage does not improve, but rather worsens, the accuracy of episodic memory retrieval, suggesting an explanation for why AN is found in brain areas serving memory rather than sensory function. In conclusion, while cognitive retrieval biases might contribute to episodic memory deficits in MDD, our model suggests a mechanistic explanation that affects all episodic memories, regardless of emotional relevance.

Episodic Memories in Anxiety Disorders: Clinical Implications

PubMed Central

Zlomuzica, Armin; Dere, Dorothea; Machulska, Alla; Adolph, Dirk; Dere, Ekrem; Margraf, Jürgen

2014-01-01

The aim of this review is to summarize research on the emerging role of episodic memories in the context of anxiety disorders (AD). The available literature on explicit, autobiographical, and episodic memory function in AD including neuroimaging studies is critically discussed. We describe the methodological diversity of episodic memory research in AD and discuss the need for novel tests to measure episodic memory in a clinical setting. We argue that alterations in episodic memory functions might contribute to the etiology of AD. We further explain why future research on the interplay between episodic memory function and emotional disorders as well as its neuroanatomical foundations offers the promise to increase the effectiveness of modern psychological treatments. We conclude that one major task is to develop methods and training programs that might help patients suffering from AD to better understand, interpret, and possibly actively use their episodic memories in a way that would support therapeutic interventions and counteract the occurrence of symptoms. PMID:24795583

Neural Changes Underlying the Development of Episodic Memory During Middle Childhood

PubMed Central

Ghetti, Simona; Bunge, Silvia A.

2012-01-01

Episodic memory is central to the human experience. In typically developing children, episodic memory improves rapidly during middle childhood. While the developmental cognitive neuroscience of episodic memory remains largely uncharted, recent research has begun to provide important insights. It has long been assumed that hippocampus-dependent binding mechanisms are in place by early childhood, and that improvements in episodic memory observed during middle childhood result from the protracted development of the prefrontal cortex. We revisit the notion that binding mechanisms are age-invariant, and propose that changes in the hippocampus and its projections to cortical regions also contribute to the development of episodic memory. We further review the role of developmental changes in lateral prefrontal and parietal cortices in this development. Finally, we discuss changes in white matter tracts connecting brain regions that are critical for episodic memory. Overall, we argue that changes in episodic memory emerge from the concerted effort of a network of relevant brain structures. PMID:22770728

Considering the role of semantic memory in episodic future thinking: evidence from semantic dementia.

PubMed

Irish, Muireann; Addis, Donna Rose; Hodges, John R; Piguet, Olivier

2012-07-01

Semantic dementia is a progressive neurodegenerative condition characterized by the profound and amodal loss of semantic memory in the context of relatively preserved episodic memory. In contrast, patients with Alzheimer's disease typically display impairments in episodic memory, but with semantic deficits of a much lesser magnitude than in semantic dementia. Our understanding of episodic memory retrieval in these cohorts has greatly increased over the last decade, however, we know relatively little regarding the ability of these patients to imagine and describe possible future events, and whether episodic future thinking is mediated by divergent neural substrates contingent on dementia subtype. Here, we explored episodic future thinking in patients with semantic dementia (n=11) and Alzheimer's disease (n=11), in comparison with healthy control participants (n=10). Participants completed a battery of tests designed to probe episodic and semantic thinking across past and future conditions, as well as standardized tests of episodic and semantic memory. Further, all participants underwent magnetic resonance imaging. Despite their relatively intact episodic retrieval for recent past events, the semantic dementia cohort showed significant impairments for episodic future thinking. In contrast, the group with Alzheimer's disease showed parallel deficits across past and future episodic conditions. Voxel-based morphometry analyses confirmed that atrophy in the left inferior temporal gyrus and bilateral temporal poles, regions strongly implicated in semantic memory, correlated significantly with deficits in episodic future thinking in semantic dementia. Conversely, episodic future thinking performance in Alzheimer's disease correlated with atrophy in regions associated with episodic memory, namely the posterior cingulate, parahippocampal gyrus and frontal pole. These distinct neuroanatomical substrates contingent on dementia group were further qualified by correlational analyses that confirmed the relation between semantic memory deficits and episodic future thinking in semantic dementia, in contrast with the role of episodic memory deficits and episodic future thinking in Alzheimer's disease. Our findings demonstrate that semantic knowledge is critical for the construction of novel future events, providing the necessary scaffolding into which episodic details can be integrated. Further research is necessary to elucidate the precise contribution of semantic memory to future thinking, and to explore how deficits in self-projection manifest on behavioural and social levels in different dementia subtypes.

Imbalance of incidental encoding across tasks: an explanation for non-memory-related hippocampal activations?

PubMed

Reas, Emilie T; Brewer, James B

2013-11-01

Functional neuroimaging studies have increasingly noted hippocampal activation associated with a variety of cognitive functions--such as decision making, attention, perception, incidental learning, prediction, and working memory--that have little apparent relation to declarative memory. Such findings might be difficult to reconcile with classical hippocampal lesion studies that show remarkable sparing of cognitive functions outside the realm of declarative memory. Even the oft-reported hippocampal activations during confident episodic retrieval are not entirely congruent with evidence that hippocampal lesions reliably impair encoding but inconsistently affect retrieval. Here we explore the conditions under which the hippocampus responds during episodic recall and recognition. Our findings suggest that anterior hippocampal activity may be related to the imbalance of incidental encoding across tasks and conditions rather than due to retrieval per se. Incidental encoding and hippocampal activity may be reduced during conditions where retrieval requires greater attentional engagement. During retrieval, anterior hippocampal activity decreases with increasing search duration and retrieval effort, and this deactivation corresponds with a coincident impaired encoding of the external environment (Israel, Seibert, Black, & Brewer, 2010; Reas & Brewer, 2013; Reas, Gimbel, Hales, & Brewer, 2011). In light of this emerging evidence, we discuss the proposal that some hippocampal activity observed during memory retrieval, or other non-memory conditions, may in fact be attributable to concomitant encoding activity that is regulated by the attentional demands of the principal task. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Aging, Estrogens, and Episodic Memory in Women

PubMed Central

Henderson, Victor W.

2009-01-01

Objective To review the relation in midlife and beyond between estrogen exposures and episodic memory in women. Background Episodic memory performance declines with usual aging, and impairments in episodic memory often portend the development of Alzheimer's disease. In the laboratory, estradiol influences hippocampal function and animal learning. However, it is controversial whether estrogens affect memory after a woman's reproductive years. Method Focused literature review, including a summary of a systematic search of clinical trials of estrogens in which outcomes included an objective measure of episodic memory. Results The natural menopause transition is not associated with objective changes in episodic memory. Strong clinical trial evidence indicates that initiating estrogen-containing hormone therapy after about age 60 years does not benefit episodic memory. Clinical trial findings in middle-age women before age 60 are limited by smaller sample sizes and shorter treatment durations, but these also do not indicate substantial memory effects. Limited short-term evidence, however, suggests that estrogens may improve verbal memory after surgical menopause. Although hormone therapy initiation in old age increases dementia risk, observational studies raise the question of an early critical window during which midlife estrogen therapy reduces late-life Alzheimer's disease. However, almost no data address whether midlife estrogen therapy affects episodic memory in old age. Conclusions Episodic memory is not substantially impacted by the natural menopause transition or improved by use of estrogen-containing hormone therapy after age 60. Further research is needed to determine whether outcomes differ after surgical menopause or whether episodic memory later in life is modified by midlife estrogenic exposures. PMID:19996872

Effects of saccadic bilateral eye movements on episodic and semantic autobiographical memory fluency.

PubMed

Parker, Andrew; Parkin, Adam; Dagnall, Neil

2013-01-01

Performing a sequence of fast saccadic horizontal eye movements has been shown to facilitate performance on a range of cognitive tasks, including the retrieval of episodic memories. One explanation for these effects is based on the hypothesis that saccadic eye movements increase hemispheric interaction, and that such interactions are important for particular types of memory. The aim of the current research was to assess the effect of horizontal saccadic eye movements on the retrieval of both episodic autobiographical memory (event/incident based memory) and semantic autobiographical memory (fact based memory) over recent and more distant time periods. It was found that saccadic eye movements facilitated the retrieval of episodic autobiographical memories (over all time periods) but not semantic autobiographical memories. In addition, eye movements did not enhance the retrieval of non-autobiographical semantic memory. This finding illustrates a dissociation between the episodic and semantic characteristics of personal memory and is considered within the context of hemispheric contributions to episodic memory performance.

Effects of Saccadic Bilateral Eye Movements on Episodic and Semantic Autobiographical Memory Fluency

PubMed Central

Parker, Andrew; Parkin, Adam; Dagnall, Neil

2013-01-01

Performing a sequence of fast saccadic horizontal eye movements has been shown to facilitate performance on a range of cognitive tasks, including the retrieval of episodic memories. One explanation for these effects is based on the hypothesis that saccadic eye movements increase hemispheric interaction, and that such interactions are important for particular types of memory. The aim of the current research was to assess the effect of horizontal saccadic eye movements on the retrieval of both episodic autobiographical memory (event/incident based memory) and semantic autobiographical memory (fact based memory) over recent and more distant time periods. It was found that saccadic eye movements facilitated the retrieval of episodic autobiographical memories (over all time periods) but not semantic autobiographical memories. In addition, eye movements did not enhance the retrieval of non-autobiographical semantic memory. This finding illustrates a dissociation between the episodic and semantic characteristics of personal memory and is considered within the context of hemispheric contributions to episodic memory performance. PMID:24133435

Aging-related episodic memory decline: are emotions the key?

PubMed Central

Kinugawa, Kiyoka; Schumm, Sophie; Pollina, Monica; Depre, Marion; Jungbluth, Carolin; Doulazmi, Mohamed; Sebban, Claude; Zlomuzica, Armin; Pietrowsky, Reinhard; Pause, Bettina; Mariani, Jean; Dere, Ekrem

2013-01-01

Episodic memory refers to the recollection of personal experiences that contain information on what has happened and also where and when these events took place. Episodic memory function is extremely sensitive to cerebral aging and neurodegerative diseases. We examined episodic memory performance with a novel test in young (N = 17, age: 21–45), middle-aged (N = 16, age: 48–62) and aged but otherwise healthy participants (N = 8, age: 71–83) along with measurements of trait and state anxiety. As expected we found significantly impaired episodic memory performance in the aged group as compared to the young group. The aged group also showed impaired working memory performance as well as significantly decreased levels of trait anxiety. No significant correlation between the total episodic memory and trait or state anxiety scores was found. The present results show an age-dependent episodic memory decline along with lower trait anxiety in the aged group. Yet, it still remains to be determined whether this difference in anxiety is related to the impaired episodic memory performance in the aged group. PMID:23378831

Plastic modulation of episodic memory networks in the aging brain with cognitive decline.

PubMed

Bai, Feng; Yuan, Yonggui; Yu, Hui; Zhang, Zhijun

2016-07-15

Social-cognitive processing has been posited to underlie general functions such as episodic memory. Episodic memory impairment is a recognized hallmark of amnestic mild cognitive impairment (aMCI) who is at a high risk for dementia. Three canonical networks, self-referential processing, executive control processing and salience processing, have distinct roles in episodic memory retrieval processing. It remains unclear whether and how these sub-networks of the episodic memory retrieval system would be affected in aMCI. This task-state fMRI study constructed systems-level episodic memory retrieval sub-networks in 28 aMCI and 23 controls using two computational approaches: a multiple region-of-interest based approach and a voxel-level functional connectivity-based approach, respectively. These approaches produced the remarkably similar findings that the self-referential processing network made critical contributions to episodic memory retrieval in aMCI. More conspicuous alterations in self-referential processing of the episodic memory retrieval network were identified in aMCI. In order to complete a given episodic memory retrieval task, increases in cooperation between the self-referential processing network and other sub-networks were mobilized in aMCI. Self-referential processing mediate the cooperation of the episodic memory retrieval sub-networks as it may help to achieve neural plasticity and may contribute to the prevention and treatment of dementia. Copyright © 2016 Elsevier B.V. All rights reserved.

The low-frequency encoding disadvantage: Word frequency affects processing demands.

PubMed

Diana, Rachel A; Reder, Lynne M

2006-07-01

Low-frequency words produce more hits and fewer false alarms than high-frequency words in a recognition task. The low-frequency hit rate advantage has sometimes been attributed to processes that operate during the recognition test (e.g., L. M. Reder et al., 2000). When tasks other than recognition, such as recall, cued recall, or associative recognition, are used, the effects seem to contradict a low-frequency advantage in memory. Four experiments are presented to support the claim that in addition to the advantage of low-frequency words at retrieval, there is a low-frequency disadvantage during encoding. That is, low-frequency words require more processing resources to be encoded episodically than high-frequency words. Under encoding conditions in which processing resources are limited, low-frequency words show a larger decrement in recognition than high-frequency words. Also, studying items (pictures and words of varying frequencies) along with low-frequency words reduces performance for those stimuli. Copyright 2006 APA, all rights reserved.

Associative false consumer memory: effects of need for cognition and encoding task.

PubMed

Parker, Andrew; Dagnall, Neil

2018-04-01

Two experiments investigated the effects of product-attribute associations on false consumer memory. In both experiments, subjects were presented with sets of related product attributes under incidental encoding conditions. Later, recognition memory was tested with studied attributes, non-studied but associated attributes (critical lures) and non-studied unrelated attributes. In Experiment 1, the effect of Need for Cognition (NFC) was assessed. It was found that individuals high in NFC recognised more presented attributes and falsely recognised more associative critical lures. The increase in both true and associative false memory was accompanied by a greater number of responses that index the retrieval of detailed episodic-like information. Experiment 2, replicated the main findings through an experimental manipulation of the encoding task that required subjects to consider purchase likelihood. Explanations for these findings are considered from the perspective of activation processes and knowledge structures in the form of gist-based representations.

Functional neuroanatomical correlates of episodic memory impairment in early phase psychosis

PubMed Central

Hummer, Tom A.; Vohs, Jenifer L.; Yung, Matthew G.; Liffick, Emily; Mehdiyoun, Nicole F.; Radnovich, Alexander J.; McDonald, Brenna C.; Saykin, Andrew J.; Breier, Alan

2015-01-01

Studies have demonstrated that episodic memory (EM) is often preferentially disrupted in schizophrenia. The neural substrates that mediate EM impairment in this illness are not fully understood. Several functional magnetic resonance imaging (fMRI) studies have employed EM probe tasks to elucidate the neural underpinnings of impairment, though results have been inconsistent. The majority of EM imaging studies have been conducted in chronic forms of schizophrenia with relatively few studies in early phase patients. Early phase schizophrenia studies are important because they may provide information regarding when EM deficits occur and address potential confounds more frequently observed in chronic populations. In this study, we assessed brain activation during the performance of visual scene encoding and recognition fMRI tasks in patients with earlyphase psychosis (n=35) and age, sex, and race matched healthy control subjects (n = 20). Patients demonstrated significantly lower activation than controls in the right hippocampus and left fusiform gyrus during scene encoding and lower activation in the posterior cingulate, precuneus, and left middle temporal cortex during recognition of target scenes. Symptom levels were not related to the imaging findings, though better cognitive performance in patients was associated with greater right hippocampal activation during encoding. These results provide evidence of altered function in neuroanatomical circuitry subserving EM early in the course of psychotic illness, which may have implications for pathophysiological models of this illness. PMID:25749917

Unique and Persistent Individual Patterns of Brain Activity Across Different Memory Retrieval Tasks

PubMed Central

Miller, Michael B.; Donovan, Christa-Lynn; Van Horn, John D.; German, Elaine; Sokol-Hessner, Peter; Wolford, George L.

2009-01-01

Fourteen subjects were scanned in two fMRI sessions separated by several months. During each session, subjects performed an episodic retrieval task, a semantic retrieval task, and a working memory task. We found that 1) despite extensive intersubject variability in the pattern of activity across the whole brain, individual activity patterns were stable over time, 2) activity patterns of the same individual performing different tasks were more similar than activity patterns of different individuals performing the same task, and 3) that individual differences in decision criterion on a recognition test predicted the degree of similarity between any two individuals’ patterns of brain activity, but individual differences in memory accuracy or similarity in structural anatomy did not. These results imply that the exclusive use of group maps may be ineffective in profiling the pattern of activations for a given task. This may be particularly true for a task like episodic retrieval, which is relatively strategic and can involve widely-distributed specialized processes that are peripheral to the actual retrieval of stored information. Further, these processes may be differentially engaged depending on individual differences in cognitive processing and/or physiology. PMID:19540922

A Mathematical Model for the Hippocampus: Towards the Understanding of Episodic Memory and Imagination

NASA Astrophysics Data System (ADS)

Tsuda, I.; Yamaguti, Y.; Kuroda, S.; Fukushima, Y.; Tsukada, M.

How does the brain encode episode? Based on the fact that the hippocampus is responsible for the formation of episodic memory, we have proposed a mathematical model for the hippocampus. Because episodic memory includes a time series of events, an underlying dynamics for the formation of episodic memory is considered to employ an association of memories. David Marr correctly pointed out in his theory of archecortex for a simple memory that the hippocampal CA3 is responsible for the formation of associative memories. However, a conventional mathematical model of associative memory simply guarantees a single association of memory unless a rule for an order of successive association of memories is given. The recent clinical studies in Maguire's group for the patients with the hippocampal lesion show that the patients cannot make a new story, because of the lack of ability of imagining new things. Both episodic memory and imagining things include various common characteristics: imagery, the sense of now, retrieval of semantic information, and narrative structures. Taking into account these findings, we propose a mathematical model of the hippocampus in order to understand the common mechanism of episodic memory and imagination.

Episodic and Semantic Autobiographical Memory and Everyday Memory during Late Childhood and Early Adolescence

PubMed Central

Willoughby, Karen A.; Desrocher, Mary; Levine, Brian; Rovet, Joanne F.

2012-01-01

Few studies have examined both episodic and semantic autobiographical memory (AM) performance during late childhood and early adolescence. Using the newly developed Children’s Autobiographical Interview (CAI), the present study examined the effects of age and sex on episodic and semantic AM and everyday memory in 182 children and adolescents. Results indicated that episodic and semantic AM both improved between 8 and 16 years of age; however, age-related changes were larger for episodic AM than for semantic AM. In addition, females were found to recall more episodic AM details, but not more semantic AM details, than males. Importantly, this sex difference in episodic AM recall was attenuated under conditions of high retrieval support (i.e., the use of probing questions). The ability to clearly visualize past events at the time of recollection was related to children’s episodic AM recall performance, particularly the retrieval of perceptual details. Finally, similar age and sex effects were found between episodic AM and everyday memory ability (e.g., memory for everyday activities). More specifically, older participants and females exhibited better episodic AM and everyday memory performance than younger participants and males. Overall, the present study provides important new insight into both episodic and semantic AM performance, as well as the relation between episodic AM and everyday memory, during late childhood and adolescence. PMID:22403560

Episodic and Semantic Autobiographical Memory and Everyday Memory during Late Childhood and Early Adolescence.

PubMed

Willoughby, Karen A; Desrocher, Mary; Levine, Brian; Rovet, Joanne F

2012-01-01

Few studies have examined both episodic and semantic autobiographical memory (AM) performance during late childhood and early adolescence. Using the newly developed Children's Autobiographical Interview (CAI), the present study examined the effects of age and sex on episodic and semantic AM and everyday memory in 182 children and adolescents. Results indicated that episodic and semantic AM both improved between 8 and 16 years of age; however, age-related changes were larger for episodic AM than for semantic AM. In addition, females were found to recall more episodic AM details, but not more semantic AM details, than males. Importantly, this sex difference in episodic AM recall was attenuated under conditions of high retrieval support (i.e., the use of probing questions). The ability to clearly visualize past events at the time of recollection was related to children's episodic AM recall performance, particularly the retrieval of perceptual details. Finally, similar age and sex effects were found between episodic AM and everyday memory ability (e.g., memory for everyday activities). More specifically, older participants and females exhibited better episodic AM and everyday memory performance than younger participants and males. Overall, the present study provides important new insight into both episodic and semantic AM performance, as well as the relation between episodic AM and everyday memory, during late childhood and adolescence.

The relationship of Theory of Mind with symptoms and cognitive impairment in bipolar disorder: a prospective study.

PubMed

Ioannidi, N; Konstantakopoulos, G; Sakkas, D; Oulis, P

2015-01-01

Previous studies in bipolar disorder suggest patients' deficient performance in Theory of Mind tasks, both during manic or depressive episodes and in remission. However, most of the extant studies were cross-sectional and did not control for potential confounders such as residual symptoms or co-existent deficits in other cognitive functions. The present study is the first prospective study that assessed the effect of remission on Theory of Mind (ToM) in patients with Bipolar Disorder (BD) controlling for other cognitive deficits. ToM was assessed in 29 patients with BD type I during an episode of the illness and in remission as well as in 29 healthy controls. The two groups were pair-matched for gender, age and education level. Three tests with different levels of complexity were used to assess ToM: First Order False Belief Task, Hinting Task and Faux Pas Recognition Test. Concomitantly, a comprehensive battery of neuropsychological tests was administered to all participants assessing general intelligence, working memory, attention, speed processing, verbal learning, and memory and executive functions. The Hamilton Rating Scale for Depression, Young Mania Rating Scale, Brief Psychiatric Rating Scale, and GAF were also administered to the patients. Differences between patients--in acute phase and in remission--and the control group on neuropsychological tests were tested using one-way ANOVA with post hoc Bonferroni corrections. The effect of other cognitive deficits on patients' ToM dysfunction was controlled for using general linear models. The patients showed significantly lower performance in all ToM tests during the acute phases as compared to the control group (p values from 0.001 to 0.014). However, these impairments did not persist beyond acute mood episode, except patients' poor performance on Faux Pas (p=0.001). Additionally, patients had poorer performance compared to control group in verbal learning and memory (p<0.001) as well as visuospatial working memory (p<0.001) during both the acute and the euthymic phases of the illness. Patients also had poorer performance than healthy controls in immediate memory (p=0.026) and executive functions (p=0.001), however only during episodes of illness. Differences in Faux Pas did not remain statistically significant when the effect of verbal memory and visuospatial working memory was controlled for. Differences in other ToM tests during episodes did not remain statistically significant, when other cognitive functions that were found impaired in patients during episodes, were controlled for. The findings of this study support the hypothesis that ToM dysfunction in BD is associated with mood symptoms and it might reflect underlying cognitive deficits rather than representing a specific trait marker of the disorder.

Impact of sleep loss before learning on cortical dynamics during memory retrieval.

PubMed

Alberca-Reina, E; Cantero, J L; Atienza, M

2015-12-01

Evidence shows that sleep loss before learning decreases activation of the hippocampus during encoding and promotes forgetting. But it remains to be determined which neural systems are functionally affected during memory retrieval after one night of recovery sleep. To investigate this issue, we evaluated memory for pairs of famous people's faces with the same or different profession (i.e., semantically congruent or incongruent faces) after one night of undisturbed sleep in subjects who either underwent 4hours of acute sleep restriction (ASR, N=20) or who slept 8hours the pre-training night (controls, N=20). EEG recordings were collected during the recognition memory task in both groups, and the cortical sources generating this activity localized by applying a spatial beamforming filter in the frequency domain. Even though sleep restriction did not affect accuracy of memory performance, controls showed a much larger decrease of alpha power relative to a baseline period when compared to sleep-deprived subjects. These group differences affected a widespread frontotemporoparietal network involved in retrieval of episodic/semantic memories. Regression analyses further revealed that associative memory in the ASR group was negatively correlated with alpha power in the occipital regions, whereas the benefit of congruency in the same group was positively correlated with delta power in the left lateral prefrontal cortex. Retrieval-related decreases of alpha power have been associated with the reactivation of material-specific memory representations, whereas increases of delta power have been related to inhibition of interferences that may affect the performance of the task. We can therefore draw the conclusion that a few hours of sleep loss in the pre-training night, though insufficient to change the memory performance, is sufficient to alter the processes involved in retrieving and manipulating episodic and semantic information. Copyright © 2015 Elsevier Inc. All rights reserved.

Episodic and Semantic Aspects of Memory for Prose.

ERIC Educational Resources Information Center

Dooling, D. James

This report describes research on Bartlett's theory of constructive memory. In experiment one, schematic retention is related to Tulving's distinction between episodic and semantic memory. With the passage of time, memory for prose reflects decreasing output from episodic memory and increasing output from semantic memory. In experiment two,…

Episode-Centered Guidelines for Teacher Belief Change toward Technology Integration

ERIC Educational Resources Information Center

Er, Erkan; Kim, ChanMin

2017-01-01

Teachers' episodic memories influence their beliefs. The investigation of episodic memories can help identify the teacher beliefs that limit technology-integration. We propose the Episode-Centered Belief Change (ECBC) model that utilizes teachers' episodic memories for changing beliefs impeding effective technology integration. We also propose…

Superficial Priming in Episodic Recognition

ERIC Educational Resources Information Center

Dopkins, Stephen; Sargent, Jesse; Ngo, Catherine T.

2010-01-01

We explored the effect of superficial priming in episodic recognition and found it to be different from the effect of semantic priming in episodic recognition. Participants made recognition judgments to pairs of items, with each pair consisting of a prime item and a test item. Correct positive responses to the test item were impeded if the prime…

Hemispheric encoding/retrieval asymmetry in episodic memory: positron emission tomography findings.

PubMed Central

Tulving, E; Kapur, S; Craik, F I; Moscovitch, M; Houle, S

1994-01-01

Data are reviewed from positron emission tomography studies of encoding and retrieval processes in episodic memory. These data suggest a hemispheric encoding/retrieval asymmetry model of prefrontal involvement in encoding and retrieval of episodic memory. According to this model, the left and right prefrontal lobes are part of an extensive neuronal network that subserves episodic remembering, but the two prefrontal hemispheres play different roles. Left prefrontal cortical regions are differentially more involved in retrieval of information from semantic memory and in simultaneously encoding novel aspects of the retrieved information into episodic memory. Right prefrontal cortical regions, on the other hand, are differentially more involved in episodic memory retrieval. PMID:8134342

An ERP analysis of recognition and categorization decisions in a prototype-distortion task.

PubMed

Tunney, Richard J; Fernie, Gordon; Astle, Duncan E

2010-04-12

Theories of categorization make different predictions about the underlying processes used to represent categories. Episodic theories suggest that categories are represented in memory by storing previously encountered exemplars in memory. Prototype theories suggest that categories are represented in the form of a prototype independently of memory. A number of studies that show dissociations between categorization and recognition are often cited as evidence for the prototype account. These dissociations have compared recognition judgements made to one set of items to categorization judgements to a different set of items making a clear interpretation difficult. Instead of using different stimuli for different tests this experiment compares the processes by which participants make decisions about category membership in a prototype-distortion task and with recognition decisions about the same set of stimuli by examining the Event Related Potentials (ERPs) associated with them. Sixty-three participants were asked to make categorization or recognition decisions about stimuli that either formed an artificial category or that were category non-members. We examined the ERP components associated with both kinds of decision for pre-exposed and control participants. In contrast to studies using different items we observed no behavioural differences between the two kinds of decision; participants were equally able to distinguish category members from non-members, regardless of whether they were performing a recognition or categorisation judgement. Interestingly, this did not interact with prior-exposure. However, the ERP data demonstrated that the early visual evoked response that discriminated category members from non-members was modulated by which judgement participants performed and whether they had been pre-exposed to category members. We conclude from this that any differences between categorization and recognition reflect differences in the information that participants focus on in the stimuli to make the judgements at test, rather than any differences in encoding or process.

An ERP Analysis of Recognition and Categorization Decisions in a Prototype-Distortion Task

PubMed Central

Tunney, Richard J.; Fernie, Gordon; Astle, Duncan E.

2010-01-01

Background Theories of categorization make different predictions about the underlying processes used to represent categories. Episodic theories suggest that categories are represented in memory by storing previously encountered exemplars in memory. Prototype theories suggest that categories are represented in the form of a prototype independently of memory. A number of studies that show dissociations between categorization and recognition are often cited as evidence for the prototype account. These dissociations have compared recognition judgements made to one set of items to categorization judgements to a different set of items making a clear interpretation difficult. Instead of using different stimuli for different tests this experiment compares the processes by which participants make decisions about category membership in a prototype-distortion task and with recognition decisions about the same set of stimuli by examining the Event Related Potentials (ERPs) associated with them. Method Sixty-three participants were asked to make categorization or recognition decisions about stimuli that either formed an artificial category or that were category non-members. We examined the ERP components associated with both kinds of decision for pre-exposed and control participants. Conclusion In contrast to studies using different items we observed no behavioural differences between the two kinds of decision; participants were equally able to distinguish category members from non-members, regardless of whether they were performing a recognition or categorisation judgement. Interestingly, this did not interact with prior-exposure. However, the ERP data demonstrated that the early visual evoked response that discriminated category members from non-members was modulated by which judgement participants performed and whether they had been pre-exposed to category members. We conclude from this that any differences between categorization and recognition reflect differences in the information that participants focus on in the stimuli to make the judgements at test, rather than any differences in encoding or process. PMID:20404932

Information Warfare: Evaluation of Operator Information Processing Models

DTIC Science & Technology

1997-10-01

that people can describe or report, including both episodic and semantic information. Declarative memory contains a network of knowledge represented...second dimension corresponds roughly to the distinction between episodic and semantic memory that is commonly made in cognitive psychology. Episodic ...3 is long-term memory for the discourse, a subset of episodic memory . Partition 4 is long-term semantic memory , or the knowledge-base. According to

Interdependence of episodic and semantic memory: evidence from neuropsychology.

PubMed

Greenberg, Daniel L; Verfaellie, Mieke

2010-09-01

Tulving's (1972) theory of memory draws a distinction between general knowledge (semantic memory) and memory for events (episodic memory). Neuropsychological studies have generally examined each type of memory in isolation, but theorists have long argued that these two forms of memory are interdependent. Here we review several lines of neuropsychological research that have explored the interdependence of episodic and semantic memory. The studies show that these forms of memory can affect each other both at encoding and at retrieval. We suggest that theories of memory should be revised to account for all of the interdependencies between episodic and semantic memory; they should also incorporate forms of memory that do not fit neatly into either category.

Interdependence of episodic and semantic memory: Evidence from neuropsychology

PubMed Central

GREENBERG, DANIEL L.; VERFAELLIE, MIEKE

2010-01-01

Tulving's (1972) theory of memory draws a distinction between general knowledge (semantic memory) and memory for events (episodic memory). Neuropsychological studies have generally examined each type of memory in isolation, but theorists have long argued that these two forms of memory are interdependent. Here we review several lines of neuropsychological research that have explored the interdependence of episodic and semantic memory. The studies show that these forms of memory can affect each other both at encoding and at retrieval. We suggest that theories of memory should be revised to account for all of the interdependencies between episodic and semantic memory; they should also incorporate forms of memory that do not fit neatly into either category. PMID:20561378

Self-reference effect on memory in healthy aging, mild cognitive impairment and Alzheimer's disease: Influence of identity valence.

PubMed

Leblond, Mona; Laisney, Mickaël; Lamidey, Virginie; Egret, Stéphanie; de La Sayette, Vincent; Chételat, Gaël; Piolino, Pascale; Rauchs, Géraldine; Desgranges, Béatrice; Eustache, Francis

2016-01-01

The self-reference effect (SRE) has been shown to benefit episodic memory in healthy individuals. In healthy aging, its preservation is acknowledged, but in Alzheimer's disease (AD), the jury is still out. Furthermore, there has yet to be a study of the SRE in amnestic mild cognitive impairment (aMCI). As self-reference implies subjective self-representations, and positive information enhance memory performance, we set out to examine the effects of 1) material and 2) identity valence on the SRE across the early stages of AD. Twenty healthy older individuals and 40 patients (20 diagnosed with aMCI and 20 diagnosed with mild AD) performed a memory task. Participants had to judge positive and negative personality trait adjectives with reference to themselves or to another person, or else process these adjectives semantically. We then administered a recognition task. Participants also completed a questionnaire on identity valence. Among healthy older individuals, the SRE benefited episodic memory independently of material and identity valence. By contrast, among aMCI patients, we only observed the SRE when the material was positive. When self-referential material was negative, patients' performance depended on the valence of their self-representations: negative self-representations correlated with poor recognition of negative self-referential adjectives. Finally, performance of patients with mild AD by condition and material valence were too low and inappropriate to be subjected to relevant analyses. The persistence of an SRE for positive adjectives in aMCI suggests the existence of a positivity effect for self-related information, which contributes to wellbeing. The absence of an SRE for negative adjectives, which led aMCI patients to dismiss negative self-related information, could be due to low self-esteem. These results corroborate the mnenic neglect model and point out the importance of the psychoaffective dimension in patients with aMCI, which could constitute a major factor for the preservation of their self-esteem and self-related memory. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sex differences in episodic memory: the impact of verbal and visuospatial ability.

PubMed

Herlitz, A; Airaksinen, E; Nordström, E

1999-10-01

The impact of verbal and visuospatial ability on sex differences in episodic memory was investigated. One hundred men and 100 women, 2040 years old, participated in a series of verbal and visuospatial tasks. Episodic memory was assessed in tasks that, to a greater or lesser extent, were verbal or visuospatial in nature. Results showed that women excelled in verbal production tasks and that men performed at a superior level on a mental rotation task. In addition, women tended to perform at a higher level than men on most episodic memory tasks. Taken together, the results demonstrated that (a) women perform at a higher level than men on most verbal episodic memory tasks and on some episodic memory tasks with a visuospatial component, and (b) women's higher performance on episodic memory tasks cannot fully be explained by their superior performance on verbal production tasks.

Developmental Differences in Relations between Episodic Memory and Hippocampal Subregion Volume during Early Childhood

ERIC Educational Resources Information Center

Riggins, Tracy; Blankenship, Sarah L.; Mulligan, Elizabeth; Rice, Katherine; Redcay, Elizabeth

2015-01-01

Episodic memory shows striking improvement during early childhood. However, neural contributions to these behavioral changes are not well understood. This study examined associations between episodic memory and volume of subregions (head, body, and tail) of the hippocampus--a structure known to support episodic memory in school-aged children and…

Episodic autobiographical memory is associated with variation in the size of hippocampal subregions.

PubMed

Palombo, Daniela J; Bacopulos, Agnes; Amaral, Robert S C; Olsen, Rosanna K; Todd, Rebecca M; Anderson, Adam K; Levine, Brian

2018-02-01

Striking individual differences exist in the human capacity to recollect past events, yet, little is known about the neural correlates of such individual differences. Studies investigating hippocampal volume in relation to individual differences in laboratory measures of episodic memory in young adults suggest that whole hippocampal volume is unrelated (or even negatively associated) with episodic memory. However, anatomical and functional specialization across hippocampal subregions suggests that individual differences in episodic memory may be linked to particular hippocampal subregions, as opposed to whole hippocampal volume. Given that the DG/CA 2/3 circuitry is thought to be especially critical for supporting episodic memory in humans, we predicted that the volume of this region would be associated with individual variability in episodic memory. This prediction was supported using high-resolution MRI of the hippocampal subfields and measures of real-world (autobiographical) episodic memory. In addition to the association with DG/CA 2/3 , we further observed a relationship between episodic autobiographical memory and subiculum volume, whereas no association was observed with CA 1 or with whole hippocampal volume. These findings provide insight into the possible neural substrates that mediate individual differences in real-world episodic remembering in humans. © 2017 Wiley Periodicals, Inc.

Mutual Influence of Reward Anticipation and Emotion on Brain Activity during Memory Retrieval.

PubMed

Yan, Chunping; Liu, Fang; Li, Yunyun; Zhang, Qin; Cui, Lixia

2017-01-01

Previous studies on the joint effect of reward motivation and emotion on memory retrieval have obtained inconsistent results. Furthermore, whether and how any such joint effect might vary over time remains unclear too. Accordingly, using the event-related potential (ERP) measurement of high temporal resolution, our study investigates the cognitive and brain mechanisms of monetary reward and emotion affecting the retrieval processes of episodic memory. Twenty undergraduate and graduate students participated in the research, and our study's behavioral results indicated that reward (relative to no reward) and negative emotion (relative to positive and neutral emotion) significantly improved recognition performance. The ERP results showed that there were significant interactions between monetary reward and emotion on memory retrieval, and the reward effects of positive, neutral, and negative memory occurred at varied intervals in mean amplitude. The reward effect of positive memory appeared relatively early, at 260-330 ms after the stimulus onset in the frontal-frontocentral area, at 260-500 ms in the centroparietal-parietal area and at 500-700 ms in the frontocentral area. However, the reward effects of neutral and negative memory occurred relatively later, and that of negative memory appeared at 500-700 ms in the frontocentral and centroparietal area and that of neutral memory was at 500-700 ms in the frontocentral and centroparietal-parietal area. Meanwhile, significant FN400 old/new effects were observed in the negative and rewarded positive items, and the old/new effects of negative items appeared earlier at FN400 than positive items. Also, significant late positive component (LPC) old/new effects were found in the positive, negative, and rewarded neutral items. These results suggest that, monetary reward and negative emotion significantly improved recognition performance, and there was a mutual influence between reward and emotion on brain activity during memory retrieval.

Gender differences in episodic memory and visual working memory including the effects of age.

PubMed

Pauls, Franz; Petermann, Franz; Lepach, Anja Christina

2013-01-01

Analysing the relationship between gender and memory, and examining the effects of age on the overall memory-related functioning, are the ongoing goals of psychological research. The present study examined gender and age group differences in episodic memory with respect to the type of task. In addition, these subgroup differences were also analysed in visual working memory. A sample of 366 women and 330 men, aged between 16 and 69 years of age, participated in the current study. Results indicate that women outperformed men on auditory memory tasks, whereas male adolescents and older male adults showed higher level performances on visual episodic and visual working memory measures. However, the size of gender-linked effects varied somewhat across age groups. Furthermore, results partly support a declining performance on episodic memory and visual working memory measures with increasing age. Although age-related losses in episodic memory could not be explained by a decreasing verbal and visuospatial ability with age, women's advantage in auditory episodic memory could be explained by their advantage in verbal ability. Men's higher level visual episodic memory performance was found to result from their advantage in visuospatial ability. Finally, possible methodological, biological, and cognitive explanations for the current findings are discussed.

The Pivotal Role of Semantic Memory in Remembering the Past and Imagining the Future

PubMed Central

Irish, Muireann; Piguet, Olivier

2013-01-01

Episodic memory refers to a complex and multifaceted process which enables the retrieval of richly detailed evocative memories from the past. In contrast, semantic memory is conceptualized as the retrieval of general conceptual knowledge divested of a specific spatiotemporal context. The neural substrates of the episodic and semantic memory systems have been dissociated in healthy individuals during functional imaging studies, and in clinical cohorts, leading to the prevailing view that episodic and semantic memory represent functionally distinct systems subtended by discrete neurobiological substrates. Importantly, however, converging evidence focusing on widespread neural networks now points to significant overlap between those regions essential for retrieval of autobiographical memories, episodic learning, and semantic processing. Here we review recent advances in episodic memory research focusing on neurodegenerative populations which has proved revelatory for our understanding of the complex interplay between episodic and semantic memory. Whereas episodic memory research has traditionally focused on retrieval of autobiographical events from the past, we also include evidence from the recent paradigm shift in which episodic memory is viewed as an adaptive and constructive process which facilitates the imagining of possible events in the future. We examine the available evidence which converges to highlight the pivotal role of semantic memory in providing schemas and meaning whether one is engaged in autobiographical retrieval for the past, or indeed, is endeavoring to construct a plausible scenario of an event in the future. It therefore seems plausible to contend that semantic processing may underlie most, if not all, forms of episodic memory, irrespective of temporal condition. PMID:23565081

The role of the thalamus and hippocampus in episodic memory performance in patients with multiple sclerosis.

PubMed

Koenig, Katherine A; Rao, Stephen M; Lowe, Mark J; Lin, Jian; Sakaie, Ken E; Stone, Lael; Bermel, Robert A; Trapp, Bruce D; Phillips, Micheal D

2018-03-01

Episodic memory loss is one of the most common cognitive symptoms in patients with multiple sclerosis (MS), but the pathophysiology of this symptom remains unclear. Both the hippocampus and thalamus have been implicated in episodic memory and show regional atrophy in patients with MS. In this work, we used functional magnetic resonance imaging (fMRI) during a verbal episodic memory task, lesion load, and volumetric measures of the hippocampus and thalamus to assess the relative contributions to verbal and visual-spatial episodic memory. Functional activation, lesion load, and volumetric measures from 32 patients with MS and 16 healthy controls were used in a predictive analysis of episodic memory function. After adjusting for disease duration, immediate recall performance on a visual-spatial episodic memory task was significantly predicted by hippocampal volume ( p < 0.003). Delayed recall on the same task was significantly predicted by volume of the left thalamus ( p < 0.003). For both memory measures, functional activation of the thalamus during encoding was more predictive than that of volume measures ( p < 0.002). Our results suggest that functional activation may be useful as a predictive measure of episodic memory loss in patients with MS.

Deficits in episodic memory and mental time travel in patients with post-traumatic stress disorder.

PubMed

Zlomuzica, Armin; Woud, Marcella L; Machulska, Alla; Kleimt, Katharina; Dietrich, Lisa; Wolf, Oliver T; Assion, Hans-Joerg; Huston, Joseph P; De Souza Silva, Maria A; Dere, Ekrem; Margraf, Jürgen

2018-04-20

Post-traumatic stress disorder (PTSD) is characterized by impairments in mnestic functions, especially in the domain of episodic memory. These alterations might affect different aspects of episodic memory functioning. Here we tested PTSD patients and healthy controls (matched for age, sex and education) in a newly developed virtual reality episodic memory test (VR-EMT), a test for mental time travel, episodic future thinking, and prospective memory (M3xT). In a cross-validation experiment, their performance was further evaluated in the Rivermead Behavioral Memory Test (RBMT). PTSD patients demonstrated impairments in episodic memory formation and mental time travel and showed difficulties in utilizing information from episodic memory to solve problems. Diminished attention and concentration in PTSD did not account for performance deficits in these tasks but higher levels of negative arousal were found in PTSD patients. Furthermore, performance in the VR-EMT and RBMT in PTSD patients correlated negatively with self-reported measures of stress and depression. Our results suggest that deficits in episodic memory formation and mental time travel in PTSD lead to difficulties in utilizing the content of episodic memories for solving problems in the present or to plan future behavior. Clinical implications of these findings and suggestions for cognitive-behavioral treatment of PTSD are discussed. Copyright © 2018 Elsevier Inc. All rights reserved.

Verbal predicates foster conscious recollection but not familiarity of a task-irrelevant perceptual feature--an ERP study.

PubMed

Ecker, Ullrich K H; Arend, Anna M; Bergström, Kirstin; Zimmer, Hubert D

2009-09-01

Research on the effects of perceptual manipulations on recognition memory has suggested that (a) recollection is selectively influenced by task-relevant information and (b) familiarity can be considered perceptually specific. The present experiment tested divergent assumptions that (a) perceptual features can influence conscious object recollection via verbal code despite being task-irrelevant and that (b) perceptual features do not influence object familiarity if study is verbal-conceptual. At study, subjects named objects and their presentation colour; this was followed by an old/new object recognition test. Event-related potentials (ERP) showed that a study-test manipulation of colour impacted selectively on the ERP effect associated with recollection, while a size manipulation showed no effect. It is concluded that (a) verbal predicates generated at study are potent episodic memory agents that modulate recollection even if the recovered feature information is task-irrelevant and (b) commonly found perceptual match effects on familiarity critically depend on perceptual processing at study.

Neural processing of recollection, familiarity and priming at encoding: evidence from a forced-choice recognition paradigm.

PubMed

Meng, Yingfang; Ye, Xiaohong; Gonsalves, Brian D

2014-10-17

The distinction between neural mechanisms of explicit and implicit expressions of memory has been well studied at the retrieval stage, but less at encoding. In addition, dissociations obtained in many studies are complicated by methodological difficulties in obtaining process-pure measures of different types of memory. In this experiment, we applied a subsequent memory paradigm and a two-stage forced-choice recognition test to classify study ERP data into four categories: subsequent remembered (later retrieved accompanied by detailed information), subsequent known (later retrieved accompanied by a feeling of familiarity), subsequent primed (later retrieved without conscious awareness) and subsequent forgotten (not retrieved). Differences in subsequent memory effects (DM effects) were measured by comparing ERP waveform associated with later memory based on recollection, familiarity or priming with ERP waveform for later forgotten items. The recollection DM effect involved a robust sustained (onset at 300 ms) prefrontal positive-going DM effect which was right-lateralized, and a later (onset at 800 ms) occipital negative-going DM effect. Familiarity involved an earlier (300-400 ms) prefrontal positive-going DM effect and a later (500-600 ms) parietal positive-going DM effect. Priming involved a negative-going DM effect which onset at 600 ms, mainly distributed over anterior brain sites. These results revealed a sequence of components that represented cognitive processes underlying the encoding of verbal information into episodic memory, and separately supported later remembering, knowing and priming. Copyright © 2014 Elsevier B.V. All rights reserved.

Medial temporal lobe function during emotional memory in early Alzheimer’s disease, mild cognitive impairment and healthy ageing: an fMRI study

PubMed Central

2013-01-01

Background Relative to intentional memory encoding, which quickly declines in Mild Cognitive Impairment (MCI) and Alzheimer’s disease (AD), incidental memory for emotional stimuli appears to deteriorate more slowly. We hypothesised that tests of incidental emotional memory may inform on different aspects of cognitive decline in MCI and AD. Methods Patients with MCI, AD and Healthy Controls (HC) were asked to attend to emotional pictures (i.e., positive and neutral) sequentially presented during an fMRI session. Attention was monitored behaviourally. A surprise post-scan recognition test was then administered. Results The groups remained attentive within the scanner. The post-scan recognition pattern was in the form of (HC = MCI) > AD, with only the former group showing a clear benefit from emotional pictures. fMRI analysis of incidental encoding demonstrated clusters of activation in para-hippocampal regions and in the hippocampus in HC and MCI patients but not in AD patients. The pattern of activation observed in MCI patients tended to be greater than that found in HC. Conclusions The results suggest that incidental emotional memory might offer a suitable platform to investigate, using behavioural and fMRI measures, subtle changes in the process of developing AD. These changes seem to differ from those found using standard episodic memory tests. The underpinnings of such differences and the potential clinical use of this methodology are discussed in depth. PMID:23497150

Emotional false memories in children with learning disabilities.

PubMed

Mirandola, Chiara; Losito, Nunzia; Ghetti, Simona; Cornoldi, Cesare

2014-02-01

Research has shown that children with learning disabilities (LD) are less prone to evince associative illusions of memory as a result of impairments in their ability to engage in semantic processing. However, it is unclear whether this observation is true for scripted life events, especially if they include emotional content, or across a broad spectrum of learning disabilities. The present study addressed these issues by assessing recognition memory for script-like information in children with nonverbal learning disability (NLD), children with dyslexia, and typically developing children (N=51). Participants viewed photographs about 8 common events (e.g., family dinner), and embedded in each episode was either a negative or a neutral consequence of an unseen action. Children's memory was then tested on a yes/no recognition task that included old and new photographs. Results showed that the three groups performed similarly in recognizing target photographs, but exhibited differences in memory errors. Compared to other groups, children with NLD were more likely to falsely recognize photographs that depicted an unseen cause of an emotional seen event and associated more "Remember" responses to these errors. Children with dyslexia were equally likely to falsely recognize both unseen causes of seen photographs and photographs generally consistent with the script, whereas the other participant groups were more likely to falsely recognize unseen causes rather than script-consistent distractors. Results are interpreted in terms of mechanisms underlying false memories' formation in different clinical populations of children with LD. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cortical Thickness and Episodic Memory Impairment in Systemic Lupus Erythematosus.

PubMed

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

2017-01-01

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

White matter structural connectivity and episodic memory in early childhood.

PubMed

Ngo, Chi T; Alm, Kylie H; Metoki, Athanasia; Hampton, William; Riggins, Tracy; Newcombe, Nora S; Olson, Ingrid R

2017-12-01

Episodic memory undergoes dramatic improvement in early childhood; the reason for this is poorly understood. In adults, episodic memory relies on a distributed neural network. Key brain regions that supporting these processes include the hippocampus, portions of the parietal cortex, and portions of prefrontal cortex, each of which shows different developmental profiles. Here we asked whether developmental differences in the axonal pathways connecting these regions may account for the robust gains in episodic memory in young children. Using diffusion weighted imaging, we examined whether white matter connectivity between brain regions implicated in episodic memory differed with age, and were associated with memory performance differences in 4- and 6-year-old children. Results revealed that white matter connecting the hippocampus to the inferior parietal lobule significantly predicted children's performance on episodic memory tasks. In contrast, variation in the white matter connecting the hippocampus to the medial prefrontal cortex did not relate to memory performance. These findings suggest that structural connectivity between the hippocampus and lateral parietal regions is relevant to the development of episodic memory. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

White Matter Structural Connectivity and Episodic Memory in Early Childhood

PubMed Central

Ngo, Chi T.; Alm, Kylie H.; Metoki, Athanasia; Hampton, William; Riggins, Tracy; Newcombe, Nora S.; Olson, Ingrid R.

2018-01-01

Episodic memory undergoes dramatic improvement in early childhood; the reason for this is poorly understood. In adults, episodic memory relies on a distributed neural network. Key brain regions that supporting these processes include the hippocampus, portions of the parietal cortex, and portions of prefrontal cortex, each of which shows different developmental profiles. Here we asked whether developmental differences in the axonal pathways connecting these regions may account for the robust gains in episodic memory in young children. Using diffusion weighted imaging, we examined whether white matter connectivity between brain regions implicated in episodic memory differed with age, and were associated with memory performance differences in 4- and 6-year-old children. Results revealed that white matter connecting the hippocampus to the inferior parietal lobule significantly predicted children’s performance on episodic memory tasks. In contrast, variation in the white matter connecting the hippocampus to the medial prefrontal cortex did not relate to memory performance. These findings suggest that structural connectivity between the hippocampus and lateral parietal regions is relevant to the development of episodic memory PMID:29175538

Influence of encoding focus and stereotypes on source monitoring event-related-potentials.

PubMed

Leynes, P Andrew; Nagovsky, Irina

2016-01-01

Source memory, memory for the origin of a memory, can be influenced by stereotypes and the information of focus during encoding processes. Participants studied words from two different speakers (male or female) using self-focus or other-focus encoding. Source judgments for the speaker׳s voice and Event-Related Potentials (ERPs) were recorded during test. Self-focus encoding increased dependence on stereotype information and the Late Posterior Negativity (LPN). The results link the LPN with an increase in systematic decision processes such as consulting prior knowledge to support an episodic memory judgment. In addition, other-focus encoding increased conditional source judgments and resulted in weaker old/new recognition relative to the self-focus encoding. The putative correlate of recollection (LPC) was absent during this condition and this was taken as evidence that recollection of partial information supported source judgments. Collectively, the results suggest that other-focus encoding changes source monitoring processing by altering the weight of specific memory features. Copyright © 2015 Elsevier B.V. All rights reserved.

SU30. Long-Term Memory Deficits in Schizophrenia: Are All Things Equal?

PubMed Central

Rossell, Susan

2017-01-01

Abstract Background: Kraepelin and Bleulernoted that patients with schizophrenia had significant cognitive deficits over a century ago; however, their observations with regard to long-term memory have not born out within empirical studies. They reported that episodic memory was intact but indicated that organization of memories, or semantic memory, was disordered. This study aimed to synthesize a century of research in the 2 long-term memory processes of episodic and semantic memory across the psychosis continuum: chronic patients, first-episode patients, high risk for psychosis cohorts, and persons with high schizotypy. Methods: A systematic review and meta-analysis was completed within the 2 domains of long-term memory across the psychosis continuum. Search terms included long-term memory, episodic, semantic, and derivations of these terms. The data were synthesized independently for episodic and semantic memory. Four independent populations were investigated: chronic patients, first-episode patients, high risk for psychosis cohorts, and persons with high schizotypy. Our approach followed the PRISMA guidelines. Thus, the pooled mean effect sizes are reported for 8 analyses. These effect sizes represent case cohort in comparison to a healthy control cohort. Results: The results were as follows, for episodic memory: chronic patients d = 1.12, first-episode patients d = 1.12, high risk d = 1.14, and high schizotypy d = 0.13. Thus, establishing that there is poor evidence of episodic memory deficits in persons with high schizotypy. For semantic memory, the literature showed a different pattern: chronic patients d = 1.2, first-episode patients d = 1.08, high risk d = 1.16, and high schizotypy d = 0.95. Thus, a consistent degree of semantic memory deficits across the continuum. Conclusion: The literature suggests a dissociated pattern of long-term memory deficits; whereby semantic memory abnormalities are more likely to be considered endophenotypes or cognitive markers for schizophrenia than episodic memory deficits. Differential patterns of semantic memory organization are argued to be present prior to the onset of the disorder. There is additional evidence to suggest that idiosyncratic storage of semantic material underlies the development of the usual beliefs and speech patterns present in the forms of delusions and formal thought disorder. Consequently, semantic memory might be a useful target for cognitive remediation.

Recall from Semantic and Episodic Memory.

ERIC Educational Resources Information Center

Gillund, Gary; Perlmutter, Marion

Although research in episodic recall memory, comparing younger and older adults, favors the younger adults, findings in semantic memory research are less consistent. To examine age differences in semantic and episodic memory recall, 72 young adults (mean age, 20.8) and 72 older adults (mean age 71) completed three memory tests under varied…

Development in the organization of episodic memories in middle childhood and adolescence.

PubMed

Chen, Yan; McAnally, Helena Margaret; Reese, Elaine

2013-01-01

The basic elements of autobiographical or episodic memory are established in early childhood, although the exact age at which memories gain episodic status is still under contention. The self-memory system proposed that adults use "lifetime periods" to group episodic memories together into chapters of the life story - an evolving and internalized account of significant life events that are self-defining. Two studies examined at what point in development children or adolescents begin to take advantage of lifetime-period chapters to organize their episodic memories. The results of Study 1 with 8- to 12-year-olds revealed that the ability to provide life story chapters began to emerge as early as 8 years of age. In Study 2 with adolescents aged 12-21, this ability continued to develop into late adolescence among New Zealand European (NZE) and New Zealand Chinese (NZC) adolescents; however, cultural differences also existed in the specificity of memories. NZC adolescents narrated fewer life story chapters containing specific memories than NZE adolescents. These findings support and extend current theories of episodic memory by specifying that pre-adolescents are starting to organize their episodic memories into lifetime periods, but this achievement is not fully realized until later in adolescence.

Episodic Memory Impairments in Primary Brain Tumor Patients.

PubMed

Durand, Thomas; Berzero, Giulia; Bompaire, Flavie; Hoffmann, Sabine; Léger, Isabelle; Jego, Virginie; Baruteau, Marie; Delgadillo, Daniel; Taillia, Hervé; Psimaras, Dimitri; Ricard, Damien

2018-01-04

Cognitive investigations in brain tumor patients have mostly explored episodic memory without differentiating between encoding, storage, and retrieval deficits. The aim of this study is to offer insight into the memory sub-processes affected in primary brain tumor patients and propose an appropriate assessment method. We retrospectively reviewed the clinical and memory assessments of 158 patients with primary brain tumors who had presented to our departments with cognitive complaints and were investigated using the Free and Cued Selective Reminding Test. Retrieval was the process of episodic memory most frequently affected, with deficits in this domain detected in 92% of patients with episodic memory impairments. Storage and encoding deficits were less prevalent, with impairments, respectively, detected in 41% and 23% of memory-impaired patients. The pattern of episodic memory impairment was similar across different tumor histologies and treatment modalities. Although all processes of episodic memory were found to be impaired, retrieval was by far the most widely affected function. A thorough assessment of all three components of episodic memory should be part of the regular neuropsychological evaluation in patients with primary brain tumors. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Functional retrograde amnesia: a quantitative case study.

PubMed

Schacter, D L; Wang, P L; Tulving, E; Freedman, M

1982-01-01

The memory impairment of a patient suffering from functional retrograde amnesia was assessed both during the amnesic episode and after its termination. The patient's performance on a task tapping semantic memory was nearly identical on the two test occasions, but his performance on a task tapping episodic memory substantially changed across test sessions. Cueing procedures revealed that in spite of the patient's restricted access to episodic memory during the amnesic period, a relatively intact "island" of episodic memories could be uncovered. The distinction between episodic and semantic memory, as well as the relation between organic and functional retrograde amnesia, are discussed in light of the case study.

Focal retrograde amnesia and the episodic-semantic distinction.

PubMed

Wheeler, M A; McMillan, C T

2001-03-01

This article reports a review of focal retrograde amnesia (FRA), or the phenomenon of organically based severe memory loss restricted to retrograde, or pretraumatic, memory. Cases of FRA are classified according to the type of memory loss: episodic, semantic, or both. A few different clusters of the disorder were identified. Lesions to either the anterior temporal lobes or the posterior/visual cortex can result in an FRA that devastates retrograde episodic memory, while having smaller effects on semantic memory. A number of left-hemisphere patients have FRA confined to semantic memory. There are several additional examples of FRA following minor cerebral trauma that disrupts either episodic memory alone or both episodic and semantic memory that are not accompanied by evidence of structural brain lesions. We discuss these different profiles of FRA and their implications for the understanding of memory retrieval.

Top-down and bottom-up attention-to-memory: mapping functional connectivity in two distinct networks that underlie cued and uncued recognition memory.

PubMed

Burianová, Hana; Ciaramelli, Elisa; Grady, Cheryl L; Moscovitch, Morris

2012-11-15

The objective of this study was to examine the functional connectivity of brain regions active during cued and uncued recognition memory to test the idea that distinct networks would underlie these memory processes, as predicted by the attention-to-memory (AtoM) hypothesis. The AtoM hypothesis suggests that dorsal parietal cortex (DPC) allocates effortful top-down attention to memory retrieval during cued retrieval, whereas ventral parietal cortex (VPC) mediates spontaneous bottom-up capture of attention by memory during uncued retrieval. To identify networks associated with these two processes, we conducted a functional connectivity analysis of a left DPC and a left VPC region, both identified by a previous analysis of task-related regional activations. We hypothesized that the two parietal regions would be functionally connected with distinct neural networks, reflecting their engagement in the differential mnemonic processes. We found two spatially dissociated networks that overlapped only in the precuneus. During cued trials, DPC was functionally connected with dorsal attention areas, including the superior parietal lobules, right precuneus, and premotor cortex, as well as relevant memory areas, such as the left hippocampus and the middle frontal gyri. During uncued trials, VPC was functionally connected with ventral attention areas, including the supramarginal gyrus, cuneus, and right fusiform gyrus, as well as the parahippocampal gyrus. In addition, activity in the DPC network was associated with faster response times for cued retrieval. This is the first study to show a dissociation of the functional connectivity of posterior parietal regions during episodic memory retrieval, characterized by a top-down AtoM network involving DPC and a bottom-up AtoM network involving VPC. Copyright © 2012 Elsevier Inc. All rights reserved.

How does intentionality of encoding affect memory for episodic information?

PubMed Central

Craig, Michael; Butterworth, Karla; Nilsson, Jonna; Hamilton, Colin J.; Gallagher, Peter

2016-01-01

Episodic memory enables the detailed and vivid recall of past events, including target and wider contextual information. In this paper, we investigated whether/how encoding intentionality affects the retention of target and contextual episodic information from a novel experience. Healthy adults performed (1) a What-Where-When (WWW) episodic memory task involving the hiding and delayed recall of a number of items (what) in different locations (where) in temporally distinct sessions (when) and (2) unexpected tests probing memory for wider contextual information from the WWW task. Critically, some participants were informed that memory for WWW information would be subsequently probed (intentional group), while this came as a surprise for others (incidental group). The probing of contextual information came as a surprise for all participants. Participants also performed several measures of episodic and nonepisodic cognition from which common episodic and nonepisodic factors were extracted. Memory for target (WWW) and contextual information was superior in the intentional group compared with the incidental group. Memory for target and contextual information was unrelated to factors of nonepisodic cognition, irrespective of encoding intentionality. In addition, memory for target information was unrelated to factors of episodic cognition. However, memory for wider contextual information was related to some factors of episodic cognition, and these relationships differed between the intentional and incidental groups. Our results lead us to propose the hypothesis that intentional encoding of episodic information increases the coherence of the representation of the context in which the episode took place. This hypothesis remains to be tested. PMID:27918286

Sleep benefits in parallel implicit and explicit measures of episodic memory.

PubMed

Weber, Frederik D; Wang, Jing-Yi; Born, Jan; Inostroza, Marion

2014-03-14

Research in rats using preferences during exploration as a measure of memory has indicated that sleep is important for the consolidation of episodic-like memory, i.e., memory for an event bound into specific spatio-temporal context. How these findings relate to human episodic memory is unclear. We used spontaneous preferences during visual exploration and verbal recall as, respectively, implicit and explicit measures of memory, to study effects of sleep on episodic memory consolidation in humans. During encoding before 10-h retention intervals that covered nighttime sleep or daytime wakefulness, two groups of young adults were presented with two episodes that were 1-h apart. Each episode entailed a spatial configuration of four different faces in a 3 × 3 grid of locations. After the retention interval, implicit spatio-temporal recall performance was assessed by eye-tracking visual exploration of another configuration of four faces of which two were from the first and second episode, respectively; of the two faces one was presented at the same location as during encoding and the other at another location. Afterward explicit verbal recall was assessed. Measures of implicit and explicit episodic memory retention were positively correlated (r = 0.57, P < 0.01), and were both better after nighttime sleep than daytime wakefulness (P < 0.05). In the sleep group, implicit episodic memory recall was associated with increased fast spindles during nonrapid eye movement (NonREM) sleep (r = 0.62, P < 0.05). Together with concordant observations in rats our results indicate that consolidation of genuinely episodic memory benefits from sleep.

Sleep benefits in parallel implicit and explicit measures of episodic memory

PubMed Central

Weber, Frederik D.; Wang, Jing-Yi; Born, Jan; Inostroza, Marion

2014-01-01

Research in rats using preferences during exploration as a measure of memory has indicated that sleep is important for the consolidation of episodic-like memory, i.e., memory for an event bound into specific spatio-temporal context. How these findings relate to human episodic memory is unclear. We used spontaneous preferences during visual exploration and verbal recall as, respectively, implicit and explicit measures of memory, to study effects of sleep on episodic memory consolidation in humans. During encoding before 10-h retention intervals that covered nighttime sleep or daytime wakefulness, two groups of young adults were presented with two episodes that were 1-h apart. Each episode entailed a spatial configuration of four different faces in a 3 × 3 grid of locations. After the retention interval, implicit spatio-temporal recall performance was assessed by eye-tracking visual exploration of another configuration of four faces of which two were from the first and second episode, respectively; of the two faces one was presented at the same location as during encoding and the other at another location. Afterward explicit verbal recall was assessed. Measures of implicit and explicit episodic memory retention were positively correlated (r = 0.57, P < 0.01), and were both better after nighttime sleep than daytime wakefulness (P < 0.05). In the sleep group, implicit episodic memory recall was associated with increased fast spindles during nonrapid eye movement (NonREM) sleep (r = 0.62, P < 0.05). Together with concordant observations in rats our results indicate that consolidation of genuinely episodic memory benefits from sleep. PMID:24634354

Physical Activity Is Positively Associated with Episodic Memory in Aging.

PubMed

Hayes, Scott M; Alosco, Michael L; Hayes, Jasmeet P; Cadden, Margaret; Peterson, Kristina M; Allsup, Kelly; Forman, Daniel E; Sperling, Reisa A; Verfaellie, Mieke

2015-11-01

Aging is associated with performance reductions in executive function and episodic memory, although there is substantial individual variability in cognition among older adults. One factor that may be positively associated with cognition in aging is physical activity. To date, few studies have objectively assessed physical activity in young and older adults, and examined whether physical activity is differentially associated with cognition in aging. Young (n=29, age 18-31 years) and older adults (n=31, ages 55-82 years) completed standardized neuropsychological testing to assess executive function and episodic memory capacities. An experimental face-name relational memory task was administered to augment assessment of episodic memory. Physical activity (total step count and step rate) was objectively assessed using an accelerometer, and hierarchical regressions were used to evaluate relationships between cognition and physical activity. Older adults performed more poorly on tasks of executive function and episodic memory. Physical activity was positively associated with a composite measure of visual episodic memory and face-name memory accuracy in older adults. Physical activity associations with cognition were independent of sedentary behavior, which was negatively correlated with memory performance. Physical activity was not associated with cognitive performance in younger adults. Physical activity is positively associated with episodic memory performance in aging. The relationship appears to be strongest for face-name relational memory and visual episodic memory, likely attributable to the fact that these tasks make strong demands on the hippocampus. The results suggest that physical activity relates to cognition in older, but not younger adults.

[A new assessment for episodic memory. Episodic memory test and caregiver's episodic memory test].

PubMed

Ojea Ortega, T; González Álvarez de Sotomayor, M M; Pérez González, O; Fernández Fernández, O

2013-10-01

The purpose of the episodic memory test and the caregiver's episodic memory test is to evaluate episodic memory according to its definition in a way that is feasible for families and achieves high degrees of sensitivity and specificity. We administered a test consisting of 10 questions about episodic events to 332 subjects, of whom 65 had Alzheimer's disease (AD), 115 had amnestic MCI (aMCI) and 152 showed no cognitive impairment according to Reisberg's global deterioration scale (GDS). We calculated the test's sensitivity and specificity to distinguish AD from episodic aMCI and from normal ageing. The area under the ROC curve for the diagnosis of aMCI was 0.94 and the best cut-off value was 20; for that value, sensitivity was 89% and specificity was 82%. For a diagnosis of AD, the area under the ROC curve was 0.99 and the best cut-off point was 17, with a sensitivity of 98% and a specificity of 91%. A subsequent study using similar methodology yielded similar results when the test was administered directly by the caregiver. The episodic memory test and the caregiver's episodic memory test are useful as brief screening tools for identifying patients with early-stage AD. It is suitable for use by primary care medical staff and in the home, since it can be administered by a caregiver. The test's limitations are that it must be administered by a reliable caregiver and the fact that it measures episodic memory only. Copyright © 2012 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

Episodic Memory Development: Theory of Mind Is Part of Re-Experiencing Experienced Events

ERIC Educational Resources Information Center

Perner, Josef; Kloo, Daniela; Gornik, Edith

2007-01-01

Two experiments with 3 1/2- to 6 1/2-year-old children showed that theory-of-mind development is associated with the growth of episodic memory. Episodic memory was assessed by manipulating informational conditions such that they permit or prevent the formation of episodic memories in terms of re-experiencing the recalled event. Only experienced…

Volume of hippocampal subfields and episodic memory in childhood and adolescence.

PubMed

Lee, Joshua K; Ekstrom, Arne D; Ghetti, Simona

2014-07-01

Episodic memory critically depends on the hippocampus to bind the features of an experience into memory. Episodic memory develops in childhood and adolescence, and hippocampal changes during this period may contribute to this development. Little is known, however, about how the hippocampus contributes to episodic memory development. The hippocampus is comprised of several cytoarchitectural subfields with functional significance for episodic memory. However, hippocampal subfields have not been assessed in vivo during child development, nor has their relation with episodic memory been assessed during this period. In the present study, high-resolution T2-weighted images of the hippocampus were acquired in 39 children and adolescents aged 8 to 14 years (M=11.30, SD=2.38), and hippocampal subfields were segmented using a protocol previously validated in adult populations. We first validated the method in children and adolescents and examined age-related differences in hippocampal subfields and correlations between subfield volumes and episodic memory. Significant age-related increases in the subfield volume were observed into early adolescence in the right CA3/DG and CA1. The right CA3/DG subfield volumes were positively correlated with accurate episodic memory for item-color relations, and the right CA3/DG and subiculum were negatively correlated with item false alarm rates. Subfield development appears to follow a protracted developmental trajectory, and likely plays a pivotal role in episodic memory development. Copyright © 2014 Elsevier Inc. All rights reserved.

Prefrontal activity and impaired memory encoding strategies in schizophrenia.

PubMed

Guimond, Synthia; Hawco, Colin; Lepage, Martin

2017-08-01

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

Ageing and autobiographical memory for emotional and neutral events

PubMed Central

St. Jacques, Peggy L.; Levine, Brian

2007-01-01

We investigated age-related effects in recall of emotional and neutral autobiographical memories. Protocols were scored according to episodic and non-episodic detail categories using the Autobiographical Interview. Young adults recalled a greater number of episodic details compared to older adults, whereas older adults recalled more semantic details, replicating previous findings. Both young and older adults’ emotional memories contained more overall detail than neutral ones, with the enhancement from emotion-specific to episodic details, but this did not alter the effect of age group on the pattern of episodic and semantic details. However, the age effect on episodic details was attenuated for neutral autobiographical memories. The findings suggest that age differences for emotional autobiographical recollection might reflect a more general pattern of age-related changes in memory, with impaired recall of episodic components and relative sparing of semantic aspects of autobiographical memory in older adults when compared to young adults. PMID:17534107

Impairments in Episodic-Autobiographical Memory and Emotional and Social Information Processing in CADASIL during Mid-Adulthood.

PubMed

Staniloiu, Angelica; Woermann, Friedrich G; Markowitsch, Hans J

2014-01-01

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) - is the most common genetic source of vascular dementia in adults, being caused by a mutation in NOTCH3 gene. Spontaneous de novo mutations may occur, but their frequency is largely unknown. Ischemic strokes and cognitive impairments are the most frequent manifestations, but seizures affect up to 10% of the patients. Herein, we describe a 47-year-old male scholar with a genetically confirmed diagnosis of CADASIL (Arg133Cys mutation in the NOTCH3 gene) and a seemingly negative family history of CADASIL illness, who was investigated with a comprehensive neuropsychological testing battery and neuroimaging methods. The patient demonstrated on one hand severe and accelerated deteriorations in multiple cognitive domains such as concentration, long-term memory (including the episodic-autobiographical memory domain), problem solving, cognitive flexibility and planning, affect recognition, discrimination and matching, and social cognition (theory of mind). Some of these impairments were even captured by abbreviated instruments for investigating suspicion of dementia. On the other hand the patient still possessed high crystallized (verbal) intelligence and a capacity to put forth a façade of well-preserved intellectual functioning. Although no definite conclusions can be drawn from a single case study, our findings point to the presence of additional cognitive changes in CADASIL in middle adulthood, in particular to impairments in the episodic-autobiographical memory domain and social information processing (e.g., social cognition). Whether these identified impairments are related to the patient's specific phenotype or to an ascertainment bias (e.g., a paucity of studies investigating these cognitive functions) requires elucidation by larger scale research.

Impairments in Episodic-Autobiographical Memory and Emotional and Social Information Processing in CADASIL during Mid-Adulthood

PubMed Central

Staniloiu, Angelica; Woermann, Friedrich G.; Markowitsch, Hans J.

2014-01-01

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) – is the most common genetic source of vascular dementia in adults, being caused by a mutation in NOTCH3 gene. Spontaneous de novo mutations may occur, but their frequency is largely unknown. Ischemic strokes and cognitive impairments are the most frequent manifestations, but seizures affect up to 10% of the patients. Herein, we describe a 47-year-old male scholar with a genetically confirmed diagnosis of CADASIL (Arg133Cys mutation in the NOTCH3 gene) and a seemingly negative family history of CADASIL illness, who was investigated with a comprehensive neuropsychological testing battery and neuroimaging methods. The patient demonstrated on one hand severe and accelerated deteriorations in multiple cognitive domains such as concentration, long-term memory (including the episodic-autobiographical memory domain), problem solving, cognitive flexibility and planning, affect recognition, discrimination and matching, and social cognition (theory of mind). Some of these impairments were even captured by abbreviated instruments for investigating suspicion of dementia. On the other hand the patient still possessed high crystallized (verbal) intelligence and a capacity to put forth a façade of well-preserved intellectual functioning. Although no definite conclusions can be drawn from a single case study, our findings point to the presence of additional cognitive changes in CADASIL in middle adulthood, in particular to impairments in the episodic-autobiographical memory domain and social information processing (e.g., social cognition). Whether these identified impairments are related to the patient’s specific phenotype or to an ascertainment bias (e.g., a paucity of studies investigating these cognitive functions) requires elucidation by larger scale research. PMID:25009481

Children's episodic memory.

PubMed

Ghetti, Simona; Lee, Joshua

2011-07-01

Episodic memory develops during childhood and adolescence. This trajectory depends on several underlying processes. In this article, we first discuss the development of the basic binding processes (e.g., the processes by which elements are bound together to form a memory episode) and control processes (e.g., reasoning and metamemory processes) involved in episodic remembering. Then, we discuss the role of these processes in false-memory formation. In the subsequent sections, we examine the neural substrates of the development of episodic memory. Finally, we discuss atypical development of episodic memory. As we proceed through the article, we suggest potential avenues for future research. WIREs Cogni Sci 2011 2 365-373 DOI: 10.1002/wcs.114 For further resources related to this article, please visit the WIREs website. Copyright © 2010 John Wiley & Sons, Ltd.

Play it again, Sam: brain correlates of emotional music recognition.

PubMed

Altenmüller, Eckart; Siggel, Susann; Mohammadi, Bahram; Samii, Amir; Münte, Thomas F

2014-01-01

Music can elicit strong emotions and can be remembered in connection with these emotions even decades later. Yet, the brain correlates of episodic memory for highly emotional music compared with less emotional music have not been examined. We therefore used fMRI to investigate brain structures activated by emotional processing of short excerpts of film music successfully retrieved from episodic long-term memory. Eighteen non-musicians volunteers were exposed to 60 structurally similar pieces of film music of 10 s length with high arousal ratings and either less positive or very positive valence ratings. Two similar sets of 30 pieces were created. Each of these was presented to half of the participants during the encoding session outside of the scanner, while all stimuli were used during the second recognition session inside the MRI-scanner. During fMRI each stimulation period (10 s) was followed by a 20 s resting period during which participants pressed either the "old" or the "new" button to indicate whether they had heard the piece before. Musical stimuli vs. silence activated the bilateral superior temporal gyrus, right insula, right middle frontal gyrus, bilateral medial frontal gyrus and the left anterior cerebellum. Old pieces led to activation in the left medial dorsal thalamus and left midbrain compared to new pieces. For recognized vs. not recognized old pieces a focused activation in the right inferior frontal gyrus and the left cerebellum was found. Positive pieces activated the left medial frontal gyrus, the left precuneus, the right superior frontal gyrus, the left posterior cingulate, the bilateral middle temporal gyrus, and the left thalamus compared to less positive pieces. Specific brain networks related to memory retrieval and emotional processing of symphonic film music were identified. The results imply that the valence of a music piece is important for memory performance and is recognized very fast.

Play it again, Sam: brain correlates of emotional music recognition

PubMed Central

Altenmüller, Eckart; Siggel, Susann; Mohammadi, Bahram; Samii, Amir; Münte, Thomas F.

2014-01-01

Background: Music can elicit strong emotions and can be remembered in connection with these emotions even decades later. Yet, the brain correlates of episodic memory for highly emotional music compared with less emotional music have not been examined. We therefore used fMRI to investigate brain structures activated by emotional processing of short excerpts of film music successfully retrieved from episodic long-term memory. Methods: Eighteen non-musicians volunteers were exposed to 60 structurally similar pieces of film music of 10 s length with high arousal ratings and either less positive or very positive valence ratings. Two similar sets of 30 pieces were created. Each of these was presented to half of the participants during the encoding session outside of the scanner, while all stimuli were used during the second recognition session inside the MRI-scanner. During fMRI each stimulation period (10 s) was followed by a 20 s resting period during which participants pressed either the “old” or the “new” button to indicate whether they had heard the piece before. Results: Musical stimuli vs. silence activated the bilateral superior temporal gyrus, right insula, right middle frontal gyrus, bilateral medial frontal gyrus and the left anterior cerebellum. Old pieces led to activation in the left medial dorsal thalamus and left midbrain compared to new pieces. For recognized vs. not recognized old pieces a focused activation in the right inferior frontal gyrus and the left cerebellum was found. Positive pieces activated the left medial frontal gyrus, the left precuneus, the right superior frontal gyrus, the left posterior cingulate, the bilateral middle temporal gyrus, and the left thalamus compared to less positive pieces. Conclusion: Specific brain networks related to memory retrieval and emotional processing of symphonic film music were identified. The results imply that the valence of a music piece is important for memory performance and is recognized very fast. PMID:24634661

Older adults get episodic memory boosting from noninvasive stimulation of prefrontal cortex during learning

PubMed Central

Brambilla, Michela; Cobelli, Chiara; Cohen, Leonardo G.; Cotelli, Maria

2016-01-01

Episodic memory displays the largest degree of age-related decline, a process that is accelerated in pathological conditions such as amnestic mild cognitive impairment and Alzheimer's disease. Previous studies have shown that the left lateral prefrontal cortex (PFC) contributes to the encoding of episodic memories along the life span. The aim of this randomized, double-blind, placebo-controlled study was to test the hypothesis that anodal trascranial direct current stimulation (tDCS) over the left lateral PFC during the learning phase would enhance delayed recall of verbal episodic memories in elderly individuals. Older adults learned a list of words while receiving anodal or placebo (sham) tDCS. Memory recall was tested 48 hours and 1 month later. The results showed that anodal tDCS strengthened episodic memories, an effect indicated by enhanced delayed recall (48 hours) compared to placebo stimulation (Cohen's d effect size = 1.01). The observation that PFC-tDCS during learning can boost verbal episodic memory in the elderly opens up the possibility to design-specific neurorehabilitation protocols targeted to conditions that affect episodic memory such as mild cognitive impairment. PMID:26923418

Comparison of semantic and episodic memory BOLD fMRI activation in predicting cognitive decline in older adults.

PubMed

Hantke, Nathan; Nielson, Kristy A; Woodard, John L; Breting, Leslie M Guidotti; Butts, Alissa; Seidenberg, Michael; Carson Smith, J; Durgerian, Sally; Lancaster, Melissa; Matthews, Monica; Sugarman, Michael A; Rao, Stephen M

2013-01-01

Previous studies suggest that task-activated functional magnetic resonance imaging (fMRI) can predict future cognitive decline among healthy older adults. The present fMRI study examined the relative sensitivity of semantic memory (SM) versus episodic memory (EM) activation tasks for predicting cognitive decline. Seventy-eight cognitively intact elders underwent neuropsychological testing at entry and after an 18-month interval, with participants classified as cognitively "Stable" or "Declining" based on ≥ 1.0 SD decline in performance. Baseline fMRI scanning involved SM (famous name discrimination) and EM (name recognition) tasks. SM and EM fMRI activation, along with Apolipoprotein E (APOE) ε4 status, served as predictors of cognitive outcome using a logistic regression analysis. Twenty-seven (34.6%) participants were classified as Declining and 51 (65.4%) as Stable. APOE ε4 status alone significantly predicted cognitive decline (R(2) = .106; C index = .642). Addition of SM activation significantly improved prediction accuracy (R(2) = .285; C index = .787), whereas the addition of EM did not (R(2) = .212; C index = .711). In combination with APOE status, SM task activation predicts future cognitive decline better than EM activation. These results have implications for use of fMRI in prevention clinical trials involving the identification of persons at-risk for age-associated memory loss and Alzheimer's disease.

Age-related changes in parietal lobe activation during an episodic memory retrieval task.

PubMed

Oedekoven, Christiane S H; Jansen, Andreas; Kircher, Tilo T; Leube, Dirk T

2013-05-01

The crucial role of lateral parietal regions in episodic memory has been confirmed in previous studies. While aging has an influence on retrieval of episodic memory, it remains to be examined how the involvement of lateral parietal regions in episodic memory changes with age. We investigated episodic memory retrieval in two age groups, using faces as stimuli and retrieval success as a measure of episodic memory. Young and elderly participants showed activation within a similar network, including lateral and medial parietal as well as prefrontal regions, but elderly showed a higher level of brain activation regardless of condition. Furthermore, we examined functional connectivity in the two age groups and found a more extensive network in the young group, including correlations of parietal and prefrontal regions. In the elderly, the overall stronger activation related to memory performance may indicate a compensatory process for a less extensive functional network.

Effects of semantic relatedness on recall of stimuli preceding emotional oddballs.

PubMed

Smith, Ryan M; Beversdorf, David Q

2008-07-01

Semantic and episodic memory networks function as highly interconnected systems, both relying on the hippocampal/medial temporal lobe complex (HC/MTL). Episodic memory encoding triggers the retrieval of semantic information, serving to incorporate contextual relationships between the newly acquired memory and existing semantic representations. While emotional material augments episodic memory encoding at the time of stimulus presentation, interactions between emotion and semantic memory that contribute to subsequent episodic recall are not well understood. Using a modified oddball task, we examined the modulatory effects of negative emotion on semantic interactions with episodic memory by measuring the free-recall of serially presented neutral or negative words varying in semantic relatedness. We found increased free-recall for words related to and preceding emotionally negative oddballs, suggesting that negative emotion can indirectly facilitate episodic free-recall by enhancing semantic contributions during encoding. Our findings demonstrate the ability of emotion and semantic memory to interact to mutually enhance free-recall.

Accurate forced-choice recognition without awareness of memory retrieval.

PubMed

Voss, Joel L; Baym, Carol L; Paller, Ken A

2008-06-01

Recognition confidence and the explicit awareness of memory retrieval commonly accompany accurate responding in recognition tests. Memory performance in recognition tests is widely assumed to measure explicit memory, but the generality of this assumption is questionable. Indeed, whether recognition in nonhumans is always supported by explicit memory is highly controversial. Here we identified circumstances wherein highly accurate recognition was unaccompanied by hallmark features of explicit memory. When memory for kaleidoscopes was tested using a two-alternative forced-choice recognition test with similar foils, recognition was enhanced by an attentional manipulation at encoding known to degrade explicit memory. Moreover, explicit recognition was most accurate when the awareness of retrieval was absent. These dissociations between accuracy and phenomenological features of explicit memory are consistent with the notion that correct responding resulted from experience-dependent enhancements of perceptual fluency with specific stimuli--the putative mechanism for perceptual priming effects in implicit memory tests. This mechanism may contribute to recognition performance in a variety of frequently-employed testing circumstances. Our results thus argue for a novel view of recognition, in that analyses of its neurocognitive foundations must take into account the potential for both (1) recognition mechanisms allied with implicit memory and (2) recognition mechanisms allied with explicit memory.

The Dorsolateral Prefrontal Cortex Plays a Role in Self-Initiated Elaborative Cognitive Processing during Episodic Memory Encoding: rTMS Evidence

PubMed Central

Hawco, Colin; Berlim, Marcelo T.; Lepage, Martin

2013-01-01

During episodic memory encoding, elaborative cognitive processing can improve later recall or recognition. While multiple studies examined the neural correlates of encoding strategies, few studies have explicitly focused on the self-initiation of elaborative encoding. Repetitive transcranial magnetic stimulation (rTMS), a method which can transiently disrupt neural activity, was administered during an associative encoding task. rTMS was either applied to the left dorsolateral prefrontal cortex (DLPFC) or to the vertex (a control region not involved in memory encoding) during presentation of pairs of words. Pairs could be semantically related or not related. Two encoding instructions were given, either cueing participants to analyze semantic relationships (cued condition), or to memorize the pair without any specific strategy cues (the self-initiated condition). Participants filled out a questionnaire regarding their use of memory strategies and performed a cued-recall task. We hypothesized that if the DLPFC plays a role in the self-initiation of elaborative encoding we would observe a reduction in memory performance in the self-initiated condition, particularly for related. We found a significant correlation between the effects of rTMS and strategy use, only in the self-initiated condition with related pairs. High strategy users showed reduced performance following DLPFC stimulation, while low strategy users tended to show increased recall following DLPFC stimulation during encoding. These results suggest the left DLPFC may be involved in the self-initiation of memory strategy use, and individuals may utilize different neural networks depending on their use of encoding strategies. PMID:24040072

Recall of remote episodic memory in amnesia.

PubMed

Zola-Morgan, S; Cohen, N J; Squire, L R

1983-01-01

Recall of remote episodic memory was assessed in three types of amnesic patient whose remote semantic memory had been evaluated previously. Patients with Korsakoff's syndrome, case N.A. and patients receiving electroconvulsive therapy all succeeded in recalling specific autobiographical episodes in response to single-word cues, and in many conditions performed as well as control subjects. Their pattern of performance generally paralleled that obtained in previous tests of remote semantic memory. These results argue against a view that amnesia reflects a selective deficit of episodic memory and suggest that the semantic-episodic distinction cannot illuminate the fundamental deficit in amnesia. Nor can the facts of amnesia confirm or deny the validity of this distinction in normal memory.

Episodic Memories

ERIC Educational Resources Information Center

Conway, Martin A.

2009-01-01

An account of episodic memories is developed that focuses on the types of knowledge they represent, their properties, and the functions they might serve. It is proposed that episodic memories consist of "episodic elements," summary records of experience often in the form of visual images, associated to a "conceptual frame" that provides a…

Everyday episodic memory in amnestic mild cognitive impairment: a preliminary investigation.

PubMed

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

2011-08-04

Decline in episodic memory is one of the hallmark features of Alzheimer's disease (AD) and is also a defining feature of amnestic Mild Cognitive Impairment (MCI), which is posited as a potential prodrome of AD. While deficits in episodic memory are well documented in MCI, the nature of this impairment remains relatively under-researched, particularly for those domains with direct relevance and meaning for the patient's daily life. In order to fully explore the impact of disruption to the episodic memory system on everyday memory in MCI, we examined participants' episodic memory capacity using a battery of experimental tasks with real-world relevance. We investigated episodic acquisition and delayed recall (story-memory), associative memory (face-name pairings), spatial memory (route learning and recall), and memory for everyday mundane events in 16 amnestic MCI and 18 control participants. Furthermore, we followed MCI participants longitudinally to gain preliminary evidence regarding the possible predictive efficacy of these real-world episodic memory tasks for subsequent conversion to AD. The most discriminating tests at baseline were measures of acquisition, delayed recall, and associative memory, followed by everyday memory, and spatial memory tasks, with MCI patients scoring significantly lower than controls. At follow-up (mean time elapsed: 22.4 months), 6 MCI cases had progressed to clinically probable AD. Exploratory logistic regression analyses revealed that delayed associative memory performance at baseline was a potential predictor of subsequent conversion to AD. As a preliminary study, our findings suggest that simple associative memory paradigms with real-world relevance represent an important line of enquiry in future longitudinal studies charting MCI progression over time.

Experimental Effects of Acute Exercise on Prospective Memory and False Memory.

PubMed

Green, David; Loprinzi, Paul D

2018-01-01

Research demonstrates that acute exercise can enhance retrospective episodic memory performance. However, limited research has examined the effects of acute exercise on prospective memory, and no studies have examined the effects of exercise on false memory performance. This study examined the potential effects of acute exercise on prospective memory and false memory performance. A between-group randomized controlled trial was employed, with participants (college students; M age  = 20 years) randomized into an exercise group (15-minute acute bout of treadmill walking; N = 25) or a control group (15 minutes of sitting; N = 26). Prospective memory was assessed from two laboratory and two naturalistic assessments outside the lab. False memory was assessed using a word-list trial. There were no statistically significant differences in prospective memory based on group allocation (F Group×Time  = 1.17; P = 0.32; η 2  = 0.06). However, the control group recalled more false words and had a higher rate of false memory recognition (F Group×Time  = 3.15; P = 0.01; η 2  = 0.26). These findings indicate that acute moderate-intensity aerobic exercise is not associated with prospective memory performance but provides some suggestive evidence that acute exercise may reduce the rate of false memories.

Such stuff as dreams are made on? Elaborative encoding, the ancient art of memory, and the hippocampus.

PubMed

Llewellyn, Sue

2013-12-01

This article argues that rapid eye movement (REM) dreaming is elaborative encoding for episodic memories. Elaborative encoding in REM can, at least partially, be understood through ancient art of memory (AAOM) principles: visualization, bizarre association, organization, narration, embodiment, and location. These principles render recent memories more distinctive through novel and meaningful association with emotionally salient, remote memories. The AAOM optimizes memory performance, suggesting that its principles may predict aspects of how episodic memory is configured in the brain. Integration and segregation are fundamental organizing principles in the cerebral cortex. Episodic memory networks interconnect profusely within the cortex, creating omnidirectional "landmark" junctions. Memories may be integrated at junctions but segregated along connecting network paths that meet at junctions. Episodic junctions may be instantiated during non-rapid eye movement (NREM) sleep after hippocampal associational function during REM dreams. Hippocampal association involves relating, binding, and integrating episodic memories into a mnemonic compositional whole. This often bizarre, composite image has not been present to the senses; it is not "real" because it hyperassociates several memories. During REM sleep, on the phenomenological level, this composite image is experienced as a dream scene. A dream scene may be instantiated as omnidirectional neocortical junction and retained by the hippocampus as an index. On episodic memory retrieval, an external stimulus (or an internal representation) is matched by the hippocampus against its indices. One or more indices then reference the relevant neocortical junctions from which episodic memories can be retrieved. Episodic junctions reach a processing (rather than conscious) level during normal wake to enable retrieval. If this hypothesis is correct, the stuff of dreams is the stuff of memory.

Differential Medial Temporal Lobe and Parietal Cortical Contributions to Real-world Autobiographical Episodic and Autobiographical Semantic Memory.

PubMed

Brown, Thackery I; Rissman, Jesse; Chow, Tiffany E; Uncapher, Melina R; Wagner, Anthony D

2018-04-18

Autobiographical remembering can depend on two forms of memory: episodic (event) memory and autobiographical semantic memory (remembering personally relevant semantic knowledge, independent of recalling a specific experience). There is debate about the degree to which the neural signals that support episodic recollection relate to or build upon autobiographical semantic remembering. Pooling data from two fMRI studies of memory for real-world personal events, we investigated whether medial temporal lobe (MTL) and parietal subregions contribute to autobiographical episodic and semantic remembering. During scanning, participants made memory judgments about photograph sequences depicting past events from their life or from others' lives, and indicated whether memory was based on episodic or semantic knowledge. Results revealed several distinct functional patterns: activity in most MTL subregions was selectively associated with autobiographical episodic memory; the hippocampal tail, superior parietal lobule, and intraparietal sulcus were similarly engaged when memory was based on retrieval of an autobiographical episode or autobiographical semantic knowledge; and angular gyrus demonstrated a graded pattern, with activity declining from autobiographical recollection to autobiographical semantic remembering to correct rejections of novel events. Collectively, our data offer insights into MTL and parietal cortex functional organization, and elucidate circuitry that supports different forms of real-world autobiographical memory.

Retrograde episodic memory and emotion: a perspective from patients with dissociative amnesia.

PubMed

Reinhold, Nadine; Markowitsch, Hans J

2009-09-01

With his recent definition of episodic memory Tulving [Tulving, E. (2005). Episodic memory and autonoesis: Uniquely human? In H. Terrace & J. Metcalfe (Eds.), The missing link in cognition: Evolution of self-knowing consciousness (pp. 3-56). New York: Oxford University Press] claims that this memory system is uniquely human and thereby distinguishes human beings from other, even highly developed, mammals. First we will define the term episodic memory as it is currently used in neuropsychological research by specifying the three underlying concepts of subjective time, autonoëtic consciousness, and the self. By doing so, we will strongly focus on retrograde episodic memory and its relation to emotion and self-referential processing. We support this relation with a discussion of autobiographical memory functions in psychiatric disorders such as dissociative amnesia. To illustrate the connection of emotion and retrograde episodic memory we shortly present neuropsychological data of two cases of dissociative amnesia. Both cases serve to point to the protective mechanism of a block of self-endangering memories from the episodic memory system, often described as the mnestic block syndrome. On the basis of these cases and supportive results from further cases we will conclude by pointing out similarities and differences of patients with organic and dissociative (psychogenic) amnesia.

Long-term priming of neighbours biases the word recognition process: evidence from a lexical decision task.

PubMed

Wagenmakers, Eric-Jan; Raaijmakers, Jeroen G W

2006-12-01

The role of orthographically similar words (i.e., neighbours) in the word recognition process has been studied extensively using short-term priming paradigms (e.g., Colombo, 1986). Here we demonstrate that long-term effects of neighbour priming can also be obtained. Experiment 1 showed that prior study of a neighbour (e.g., TANGO) increased later lexical decision performance for similar words (e.g., MANGO), but decreased performance for similar pseudowords (e.g., LANGO). Experiment 2 replicated this bias effect and showed that the increase in lexical decision performance due to neighbour priming is selectively due to words from a relatively sparse neighbourhood. Explanations of the bias effect in terms of lexical activation and episodic memory retrieval are discussed.

Mirror-Induced Behavior in the Magpie (Pica pica): Evidence of Self-Recognition

PubMed Central

Prior, Helmut; Schwarz, Ariane; Güntürkün, Onur

2008-01-01

Comparative studies suggest that at least some bird species have evolved mental skills similar to those found in humans and apes. This is indicated by feats such as tool use, episodic-like memory, and the ability to use one's own experience in predicting the behavior of conspecifics. It is, however, not yet clear whether these skills are accompanied by an understanding of the self. In apes, self-directed behavior in response to a mirror has been taken as evidence of self-recognition. We investigated mirror-induced behavior in the magpie, a songbird species from the crow family. As in apes, some individuals behaved in front of the mirror as if they were testing behavioral contingencies. When provided with a mark, magpies showed spontaneous mark-directed behavior. Our findings provide the first evidence of mirror self-recognition in a non-mammalian species. They suggest that essential components of human self-recognition have evolved independently in different vertebrate classes with a separate evolutionary history. PMID:18715117