attention episodic memory: Topics by Science.gov

Sample records for attention episodic memory

The influence of aging on attentional refreshing and articulatory rehearsal during working memory on later episodic memory performance.

PubMed

Loaiza, Vanessa M; McCabe, David P

2013-01-01

We investigated age-related changes in two proposed mechanisms of maintenance in working memory, articulatory rehearsal, and attentional refreshing, by examining the consequences of manipulating the opportunity for each on delayed recall. Both experiments utilized modified operation span tasks to vary the opportunity for articulatory rehearsal (Experiment 1) and attentional refreshing opportunities (Experiment 2). In both experiments, episodic memory was tested for items that had been initially studied during the respective operation span task. Older adults' episodic memory benefited less from opportunities for refreshing than younger adults. In contrast, articulatory rehearsal opportunities did not influence episodic memory for either age group. The results suggest that attentional refreshing, and not articulatory rehearsal, is important during working memory in order to bind more accessible traces at later tests, which appears to be more deficient in older adults than younger adults.
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.
Dissociable effects of top-down and bottom-up attention during episodic encoding

PubMed Central

Uncapher, Melina R.; Hutchinson, J. Benjamin; Wagner, Anthony D.

2011-01-01

It is well established that the formation of memories for life’s experiences—episodic memory—is influenced by how we attend to those experiences, yet the neural mechanisms by which attention shapes episodic encoding are still unclear. We investigated how top-down and bottom-up attention contribute to memory encoding of visual objects in humans by manipulating both types of attention during functional magnetic resonance imaging (fMRI) of episodic memory formation. We show that dorsal parietal cortex—specifically, intraparietal sulcus (IPS)—was engaged during top-down attention and was also recruited during the successful formation of episodic memories. By contrast, bottom-up attention engaged ventral parietal cortex—specifically, temporoparietal junction (TPJ)—and was also more active during encoding failure. Functional connectivity analyses revealed further dissociations in how top-down and bottom-up attention influenced encoding: while both IPS and TPJ influenced activity in perceptual cortices thought to represent the information being encoded (fusiform/lateral occipital cortex), they each exerted opposite effects on memory encoding. Specifically, during a preparatory period preceding stimulus presentation, a stronger drive from IPS was associated with a higher likelihood that the subsequently attended stimulus would be encoded. By contrast, during stimulus processing, stronger connectivity with TPJ was associated with a lower likelihood the stimulus would be successfully encoded. These findings suggest that during encoding of visual objects into episodic memory, top-down and bottom-up attention can have opposite influences on perceptual areas that subserve visual object representation, suggesting that one manner in which attention modulates memory is by altering the perceptual processing of to-be-encoded stimuli. PMID:21880922
Long-Term Episodic Memory in Children with Attention-Deficit/Hyperactivity Disorder

ERIC Educational Resources Information Center

Skowronek, Jeffrey S.; Leichtman, Michelle D.; Pillemer, David B.

2008-01-01

Twenty-nine grade-matched 4th-8th-grade males, 12 with attention-deficit/hyperactivity disorder (ADHD) (age M = 12.2 years, SD = 1.48), and 17 without (age M = 11.5, SD = 1.59), completed two working memory tasks (digit span and the Simon game) and three long-term episodic memory tasks (a personal event memory task, story memory task, and picture…
Posterior parietal cortex and episodic encoding: insights from fMRI subsequent memory effects and dual-attention theory.

PubMed

Uncapher, Melina R; Wagner, Anthony D

2009-02-01

The formation of episodic memories--memories for life events--is affected by attention during event processing. A leading neurobiological model of attention posits two separate yet interacting systems that depend on distinct regions in lateral posterior parietal cortex (PPC). From this dual-attention perspective, dorsal PPC is thought to support the goal-directed allocation of attention, whereas ventral PPC is thought to support reflexive orienting to information that automatically captures attention. To advance understanding of how parietal mechanisms may impact event encoding, we review functional MRI studies that document the relationship between lateral PPC activation during encoding and subsequent memory performance (e.g., later remembering or forgetting). This review reveals that (a) encoding-related activity is frequently observed in human lateral PPC, (b) increased activation in dorsal PPC is associated with later memory success, and (c) increased activation in ventral PPC predominantly correlates with later memory failure. From a dual-attention perspective, these findings suggest that allocating goal-directed attention during event processing increases the probability that the event will be remembered later, whereas the capture of reflexive attention during event processing may have negative consequences for event encoding. The prevalence of encoding-related activation in parietal cortex suggests that neurobiological models of episodic memory should consider how parietal-mediated attentional mechanisms regulate encoding.
Interaction between attentional systems and episodic memory encoding: the impact of conflict on binding of information.

PubMed

Sperduti, Marco; Armougum, Allan; Makowski, Dominique; Blondé, Philippe; Piolino, Pascale

2017-12-01

Episodic memory (EM) is defined as a long-term memory system that stores information that can be retrieved along with details of the context of the original events (binding). Several studies have shown that manipulation of attention during encoding can impact subsequent memory performance. An influential model of attention distinguishes between three partially independent attentional networks: the alerting, the orienting and the executive or conflict resolution component. To date, the impact of the engagement of these sub-systems during encoding on item and relational context binding has not been investigated. Here, we developed a new task combining the Attentional Network Test and an incidental episodic memory encoding task to study this issue. We reported that when the alerting network was not solicited, resolving conflict hindered item encoding. Moreover, resolving conflict, independently of the cueing condition, had a negative impact on context binding. These novel findings could have a potential impact in the understanding EM formation, and memory disorders in different populations, including healthy elderly people.
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.
Memory Performance for Everyday Motivational and Neutral Objects Is Dissociable from Attention

PubMed Central

Schomaker, Judith; Wittmann, Bianca C.

2017-01-01

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

PubMed

Cabeza, Roberto

2008-01-01

Although parietal cortex is frequently activated during episodic memory retrieval, damage to this region does not markedly impair episodic memory. To account for these and other findings, a new dual attentional processes (DAP) hypothesis is proposed. According to this hypothesis, dorsal parietal cortex (DPC) contributes top-down attentional processes guided by retrieval goals, whereas ventral parietal cortex (VPC) contributes bottom-up attentional processes captured by the retrieval output. Consistent with this hypothesis, DPC activity increases with retrieval effort whereas VPC activity increases with confidence in old and new responses. The DAP hypothesis can also account for the overlap of parietal activations across different cognitive domains and for opposing effects of parietal activity on encoding vs. retrieval. Finally, the DAP hypothesis explains why VPC lesions yield a memory neglect syndrome: a deficit in spontaneously reporting relevant memory details but not in accessing the same details when guided by specific questions.
Posterior Parietal Cortex and Episodic Encoding: Insights from fMRI Subsequent Memory Effects and Dual Attention Theory

PubMed Central

Uncapher, Melina; Wagner, Anthony D.

2010-01-01

The formation of episodic memories –– memories for life events –– is affected by attention during event processing. A leading neurobiological model of attention posits two separate yet interacting systems that depend on distinct regions in lateral posterior parietal cortex (PPC). From this dual-attention perspective, dorsal PPC is thought to support the goal-directed allocation of attention, whereas ventral PPC is thought to support reflexive orienting to information that automatically captures attention. To advance understanding of how parietal mechanisms may impact event encoding, we review functional MRI studies that document the relationship between lateral PPC activation during encoding and subsequent memory performance (e.g., later remembering or forgetting). This review reveals that (a) encoding-related activity is frequently observed in human lateral PPC, (b) increased activation in dorsal PPC is associated with later memory success, and (c) increased activation in ventral PPC predominantly correlates with later memory failure. From a dual-attention perspective, these findings suggest that allocating goal-directed attention during event processing increases the probability that the event will be remembered later, whereas the capture of reflexive attention during event processing may have negative consequences for event encoding. The prevalence of encoding-related activation in parietal cortex suggests that neurobiological models of episodic memory should consider how parietal-mediated attentional mechanisms regulate encoding. PMID:19028591
Memory functions in chronic pain: examining contributions of attention and age to test performance.

PubMed

Oosterman, Joukje M; Derksen, Laura C; van Wijck, Albert J M; Veldhuijzen, Dieuwke S; Kessels, Roy P C

2011-01-01

Previous studies have revealed that memory performance is diminished in chronic pain patients. Few studies, however, have assessed multiple components of memory in a single sample. It is currently also unknown whether attentional problems, which are commonly observed in chronic pain, mediate the decline in memory. Finally, previous studies have focused on middle-aged adults, and a possible detrimental effect of aging on memory performance in chronic pain patients has been commonly disregarded. This study, therefore, aimed at describing the pattern of semantic, working, and visual and verbal episodic memory performance in participants with chronic pain, while testing for possible contributions of attention and age to task performance. Thirty-four participants with chronic pain and 32 pain-free participants completed tests of episodic, semantic, and working memory to assess memory performance and a test of attention. Participants with chronic pain performed worse on tests of working memory and verbal episodic memory. A decline in attention explained some, but not all, group differences in memory performance. Finally, no additional effect of age on the diminished task performance in participants with chronic pain was observed. Taken together, the results indicate that chronic pain significantly affects memory performance. Part of this effect may be caused by underlying attentional dysfunction, although this could not fully explain the observed memory decline. An increase in age in combination with the presence of chronic pain did not additionally affect memory performance.
The contribution of the human posterior parietal cortex to episodic memory.

PubMed

Sestieri, Carlo; Shulman, Gordon L; Corbetta, Maurizio

2017-02-17

The posterior parietal cortex (PPC) is traditionally associated with attention, perceptual decision making and sensorimotor transformations, but more recent human neuroimaging studies support an additional role in episodic memory retrieval. In this Opinion article, we present a functional-anatomical model of the involvement of the PPC in memory retrieval. Parietal regions involved in perceptual attention and episodic memory are largely segregated and often show a push-pull relationship, potentially mediated by prefrontal regions. Moreover, different PPC regions carry out specific functions during retrieval - for example, representing retrieved information, recoding this information based on task demands, or accumulating evidence for memory decisions.
The contribution of the human posterior parietal cortex to episodic memory

PubMed Central

Sestieri, Carlo; Shulman, Gordon L.; Corbetta, Maurizio

2017-01-01

The posterior parietal cortex (PPC) is traditionally associated with attention, perceptual decision making and sensorimotor transformations, but more recent human neuroimaging studies support an additional role in episodic memory retrieval. In this Opinion article, we present a functional–anatomical model of the involvement of the PPC in memory retrieval. Parietal regions involved in perceptual attention and episodic memory are largely segregated and often show a push–pull relationship, potentially mediated by prefrontal regions. Moreover, different PPC regions carry out specific functions during retrieval — for example, representing retrieved information, recoding this information based on task demands, or accumulating evidence for memory decisions. PMID:28209980
Alzheimer Disease Cerebrospinal Fluid Biomarkers Moderate Baseline Differences and Predict Longitudinal Change in Attentional Control and Episodic Memory Composites in the Adult Children Study

PubMed Central

Aschenbrenner, Andrew J.; Balota, David A.; Fagan, Anne M.; Duchek, Janet M.; Benzinger, Tammie L.S.; Morris, John C.

2015-01-01

Objective Cognitive measures that are sensitive to biological markers of Alzheimer disease (AD) pathology are needed in order to (a) facilitate preclinical staging, (b) identify individuals who are at the highest risk for developing clinical symptoms and (c) serve as endpoints for evaluating the efficacy of interventions. The present study assesses the utility of two cognitive composite scores of attentional control and episodic memory as markers for preclinical AD pathology in a group of cognitively normal older adults (N = 238), as part of the Adult Children Study. Method All participants were given a baseline cognitive assessment and follow-up assessments every 3 years over an 8-year period, as well as a lumbar puncture within two years of the initial assessment to collect cerebrospinal fluid (CSF) and a PET-PIB scan for amyloid imaging. Results Results indicated that attentional control was correlated with levels of Aβ42 at the initial assessment whereas episodic memory was not. Longitudinally, individuals with high CSF tau exhibited a decline in both attention and episodic memory over the course of the study. Conclusion These results indicate that measures of attentional control and episodic memory can be utilized to evaluate cognitive decline in preclinical AD and provide support that CSF tau may be a key mechanism driving longitudinal cognitive change. PMID:26416094
Alzheimer Disease Cerebrospinal Fluid Biomarkers Moderate Baseline Differences and Predict Longitudinal Change in Attentional Control and Episodic Memory Composites in the Adult Children Study.

PubMed

Aschenbrenner, Andrew J; Balota, David A; Fagan, Anne M; Duchek, Janet M; Benzinger, Tammie L S; Morris, John C

2015-09-01

Cognitive measures that are sensitive to biological markers of Alzheimer disease (AD) pathology are needed to (a) facilitate preclinical staging, (b) identify individuals who are at the highest risk for developing clinical symptoms, and (c) serve as endpoints for evaluating the efficacy of interventions. The present study assesses the utility of two cognitive composite scores of attentional control and episodic memory as markers for preclinical AD pathology in a group of cognitively normal older adults (N = 238), as part of the Adult Children Study. All participants were given a baseline cognitive assessment and follow-up assessments every 3 years over an 8-year period, as well as a lumbar puncture within 2 years of the initial assessment to collect cerebrospinal fluid (CSF) and amyloid tracer Pittsburgh compound-B scan for amyloid imaging. Results indicated that attentional control was correlated with levels of Aβ42 at the initial assessment whereas episodic memory was not. Longitudinally, individuals with high CSF tau exhibited a decline in both attention and episodic memory over the course of the study. These results indicate that measures of attentional control and episodic memory can be used to evaluate cognitive decline in preclinical AD and provide support that CSF tau may be a key mechanism driving longitudinal cognitive change.
Cholinergic modulation of cognitive processing: insights drawn from computational models

PubMed Central

Newman, Ehren L.; Gupta, Kishan; Climer, Jason R.; Monaghan, Caitlin K.; Hasselmo, Michael E.

2012-01-01

Acetylcholine plays an important role in cognitive function, as shown by pharmacological manipulations that impact working memory, attention, episodic memory, and spatial memory function. Acetylcholine also shows striking modulatory influences on the cellular physiology of hippocampal and cortical neurons. Modeling of neural circuits provides a framework for understanding how the cognitive functions may arise from the influence of acetylcholine on neural and network dynamics. We review the influences of cholinergic manipulations on behavioral performance in working memory, attention, episodic memory, and spatial memory tasks, the physiological effects of acetylcholine on neural and circuit dynamics, and the computational models that provide insight into the functional relationships between the physiology and behavior. Specifically, we discuss the important role of acetylcholine in governing mechanisms of active maintenance in working memory tasks and in regulating network dynamics important for effective processing of stimuli in attention and episodic memory tasks. We also propose that theta rhythm plays a crucial role as an intermediary between the physiological influences of acetylcholine and behavior in episodic and spatial memory tasks. We conclude with a synthesis of the existing modeling work and highlight future directions that are likely to be rewarding given the existing state of the literature for both empiricists and modelers. PMID:22707936
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.
Age-related decline in verbal learning is moderated by demographic factors, working memory capacity, and presence of amnestic mild cognitive impairment.

PubMed

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

2014-09-01

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

PubMed Central

Schneider, Werner X.

2013-01-01

The goal of this review is to introduce a theory of task-driven visual attention and working memory (TRAM). Based on a specific biased competition model, the ‘theory of visual attention’ (TVA) and its neural interpretation (NTVA), TRAM introduces the following assumption. First, selective visual processing over time is structured in competition episodes. Within an episode, that is, during its first two phases, a limited number of proto-objects are competitively encoded—modulated by the current task—in activation-based visual working memory (VWM). In processing phase 3, relevant VWM objects are transferred via a short-term consolidation into passive VWM. Second, each time attentional priorities change (e.g. after an eye movement), a new competition episode is initiated. Third, if a phase 3 VWM process (e.g. short-term consolidation) is not finished, whereas a new episode is called, a protective maintenance process allows its completion. After a VWM object change, its protective maintenance process is followed by an encapsulation of the VWM object causing attentional resource costs in trailing competition episodes. Viewed from this perspective, a new explanation of key findings of the attentional blink will be offered. Finally, a new suggestion will be made as to how VWM items might interact with visual search processes. PMID:24018722

The Asymmetrical Effects of Divided Attention on Encoding and Retrieval Processes: A Different View Based on an Interference with the Episodic Register

PubMed Central

Guez, Jonathan; Naveh-Benjamin, Moshe

2013-01-01

In this study, we evaluate the conceptualization of encoding and retrieval processes established in previous studies that used a divided attention (DA) paradigm. These studies indicated that there were considerable detrimental effects of DA at encoding on later memory performance, but only minimal effects, if any, on divided attention at retrieval. We suggest that this asymmetry in the effects of DA on memory can be due, at least partially, to a confound between the memory phase (encoding and retrieval) and the memory requirements of the task (memory “for” encoded information versus memory “at” test). To control for this confound, we tested memory for encoded information and for retrieved information by introducing a second test that assessed memory for the retrieved information from the first test. We report the results of four experiments that use measures of memory performance, retrieval latency, and performance on the concurrent task, all of which consistently show that DA at retrieval strongly disrupts later memory for the retrieved episode, similarly to the effects of DA at encoding. We suggest that these symmetrical disruptive effects of DA at encoding and retrieval on later retrieval reflect a disruption of an episodic buffer (EB) or episodic register component (ER), rather than a failure of encoding or retrieval operations per se. PMID:24040249
The asymmetrical effects of divided attention on encoding and retrieval processes: a different view based on an interference with the episodic register.

PubMed

Guez, Jonathan; Naveh-Benjamin, Moshe

2013-01-01

In this study, we evaluate the conceptualization of encoding and retrieval processes established in previous studies that used a divided attention (DA) paradigm. These studies indicated that there were considerable detrimental effects of DA at encoding on later memory performance, but only minimal effects, if any, on divided attention at retrieval. We suggest that this asymmetry in the effects of DA on memory can be due, at least partially, to a confound between the memory phase (encoding and retrieval) and the memory requirements of the task (memory "for" encoded information versus memory "at" test). To control for this confound, we tested memory for encoded information and for retrieved information by introducing a second test that assessed memory for the retrieved information from the first test. We report the results of four experiments that use measures of memory performance, retrieval latency, and performance on the concurrent task, all of which consistently show that DA at retrieval strongly disrupts later memory for the retrieved episode, similarly to the effects of DA at encoding. We suggest that these symmetrical disruptive effects of DA at encoding and retrieval on later retrieval reflect a disruption of an episodic buffer (EB) or episodic register component (ER), rather than a failure of encoding or retrieval operations per se.
Functional Heterogeneity in Posterior Parietal Cortex Across Attention and Episodic Memory Retrieval

PubMed Central

Hutchinson, J. Benjamin; Uncapher, Melina R.; Weiner, Kevin S.; Bressler, David W.; Silver, Michael A.; Preston, Alison R.; Wagner, Anthony D.

2014-01-01

While attention is critical for event memory, debate has arisen regarding the extent to which posterior parietal cortex (PPC) activation during episodic retrieval reflects engagement of PPC-mediated mechanisms of attention. Here, we directly examined the relationship between attention and memory, within and across subjects, using functional magnetic resonance imaging attention-mapping and episodic retrieval paradigms. During retrieval, 4 functionally dissociable PPC regions were identified. Specifically, 2 PPC regions positively tracked retrieval outcomes: lateral intraparietal sulcus (latIPS) indexed graded item memory strength, whereas angular gyrus (AnG) tracked recollection. By contrast, 2 other PPC regions demonstrated nonmonotonic relationships with retrieval: superior parietal lobule (SPL) tracked retrieval reaction time, consistent with a graded engagement of top-down attention, whereas temporoparietal junction displayed a complex pattern of below-baseline retrieval activity, perhaps reflecting disengagement of bottom-up attention. Analyses of retrieval effects in PPC topographic spatial attention maps (IPS0-IPS5; SPL1) revealed that IPS5 and SPL1 exhibited a nonmonotonic relationship with retrieval outcomes resembling that in the SPL region, further suggesting that SPL activation during retrieval reflects top-down attention. While demands on PPC attention mechanisms vary during retrieval attempts, the present functional parcellation of PPC indicates that 2 additional mechanisms (mediated by latIPS and AnG) positively track retrieval outcomes. PMID:23019246
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.
Overlapping Parietal Activity in Memory and Perception: Evidence for the Attention to Memory Model

ERIC Educational Resources Information Center

Cabeza, Roberto; Mazuz, Yonatan S.; Stokes, Jared; Kragel, James E.; Woldorff, Marty G.; Ciaramelli, Elisa; Olson, Ingrid R.; Moscovitch, Morris

2011-01-01

The specific role of different parietal regions to episodic retrieval is a topic of intense debate. According to the Attention to Memory (AtoM) model, dorsal parietal cortex (DPC) mediates top-down attention processes guided by retrieval goals, whereas ventral parietal cortex (VPC) mediates bottom-up attention processes captured by the retrieval…
Memory and selective attention in multiple sclerosis: cross-sectional computer-based assessment in a large outpatient sample.

PubMed

Adler, Georg; Lembach, Yvonne

2015-08-01

Cognitive impairments may have a severe impact on everyday functioning and quality of life of patients with multiple sclerosis (MS). However, there are some methodological problems in the assessment and only a few studies allow a representative estimate of the prevalence and severity of cognitive impairments in MS patients. We applied a computer-based method, the memory and attention test (MAT), in 531 outpatients with MS, who were assessed at nine neurological practices or specialized outpatient clinics. The findings were compared with those obtained in an age-, sex- and education-matched control group of 84 healthy subjects. Episodic short-term memory was substantially decreased in the MS patients. About 20% of them reached a score of only less than two standard deviations below the mean of the control group. The episodic short-term memory score was negatively correlated with the EDSS score. Minor but also significant impairments in the MS patients were found for verbal short-term memory, episodic working memory and selective attention. The computer-based MAT was found to be useful for a routine assessment of cognition in MS outpatients.
The impact of social activities, social networks, social support and social relationships on the cognitive functioning of healthy older adults: a systematic review.

PubMed

Kelly, Michelle E; Duff, Hollie; Kelly, Sara; McHugh Power, Joanna E; Brennan, Sabina; Lawlor, Brian A; Loughrey, David G

2017-12-19

Social relationships, which are contingent on access to social networks, promote engagement in social activities and provide access to social support. These social factors have been shown to positively impact health outcomes. In the current systematic review, we offer a comprehensive overview of the impact of social activities, social networks and social support on the cognitive functioning of healthy older adults (50+) and examine the differential effects of aspects of social relationships on various cognitive domains. We followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines, and collated data from randomised controlled trials (RCTs), genetic and observational studies. Independent variables of interest included subjective measures of social activities, social networks, and social support, and composite measures of social relationships (CMSR). The primary outcome of interest was cognitive function divided into domains of episodic memory, semantic memory, overall memory ability, working memory, verbal fluency, reasoning, attention, processing speed, visuospatial abilities, overall executive functioning and global cognition. Thirty-nine studies were included in the review; three RCTs, 34 observational studies, and two genetic studies. Evidence suggests a relationship between (1) social activity and global cognition and overall executive functioning, working memory, visuospatial abilities and processing speed but not episodic memory, verbal fluency, reasoning or attention; (2) social networks and global cognition but not episodic memory, attention or processing speed; (3) social support and global cognition and episodic memory but not attention or processing speed; and (4) CMSR and episodic memory and verbal fluency but not global cognition. The results support prior conclusions that there is an association between social relationships and cognitive function but the exact nature of this association remains unclear. Implications of the findings are discussed and suggestions for future research provided. PROSPERO 2012: CRD42012003248 .
Functional Magnetic Resonance Imaging Correlates of First-Episode Psychoses during Attentional and Memory Task Performance.

PubMed

Del Casale, Antonio; Kotzalidis, Georgios D; Rapinesi, Chiara; Sorice, Serena; Girardi, Nicoletta; Ferracuti, Stefano; Girardi, Paolo

2016-01-01

The nature of the alteration of the response to cognitive tasks in first-episode psychosis (FEP) still awaits clarification. We used activation likelihood estimation, an increasingly used method in evaluating normal and pathological brain function, to identify activation changes in functional magnetic resonance imaging (fMRI) studies of FEP during attentional and memory tasks. We included 11 peer-reviewed fMRI studies assessing FEP patients versus healthy controls (HCs) during performance of attentional and memory tasks. Our database comprised 290 patients with FEP, matched with 316 HCs. Between-group analyses showed that HCs, compared to FEP patients, exhibited hyperactivation of the right middle frontal gyrus (Brodmann area, BA, 9), right inferior parietal lobule (BA 40), and right insula (BA 13) during attentional task performances and hyperactivation of the left insula (BA 13) during memory task performances. Right frontal, parietal, and insular dysfunction during attentional task performance and left insular dysfunction during memory task performance are significant neural functional FEP correlates. © 2016 S. Karger AG, Basel.
Attention improves memory by suppressing spiking-neuron activity in the human anterior temporal lobe.

PubMed

Wittig, John H; Jang, Anthony I; Cocjin, John B; Inati, Sara K; Zaghloul, Kareem A

2018-06-01

We identify a memory-specific attention mechanism in the human anterior temporal lobe, an area implicated in semantic processing and episodic memory formation. Spiking neuron activity is suppressed and becomes more reliable in preparation for verbal memory formation. Intracranial electroencephalography signals implicate this region as a source of executive control for attentional selection. Consistent with this interpretation, its surgical removal causes significant memory impairment for attended words relative to unattended words.
Fractionation of the component processes underlying successful episodic encoding: a combined fMRI and divided-attention study.

PubMed

Uncapher, Melina R; Rugg, Michael D

2008-02-01

Considerable evidence suggests that attentional resources are necessary for the encoding of episodic memories, but the nature of the relationship between attention and neural correlates of encoding is unclear. Here we address this question using functional magnetic resonance imaging and a divided-attention paradigm in which competition for different types of attentional resources was manipulated. Fifteen volunteers were scanned while making animacy judgments to visually presented words and concurrently performing one of three tasks on auditorily presented words: male/female voice discrimination (control task), 1-back voice comparison (1-back task), or indoor/outdoor judgment (semantic task). The 1-back and semantic tasks were designed to compete for task-generic and task-specific attentional resources, respectively. Using the "remember/know" procedure, memory for the study words was assessed after 15 min. In the control condition, subsequent memory effects associated with later recollection were identified in the left dorsal inferior frontal gyrus and in the left hippocampus. These effects were differentially attenuated in the two more difficult divided-attention conditions. The effects of divided attention seem, therefore, to reflect impairments due to limitations at both task-generic and task-specific levels. Additionally, each of the two more difficult divided-attention conditions was associated with subsequent memory effects in regions distinct from those showing effects in the control condition. These findings suggest the engagement of alternative encoding processes to those engaged in the control task. The overall pattern of findings suggests that divided attention can impact later memory in different ways, and accordingly, that different attentional resources, including task-generic and task-specific resources, make distinct contributions to successful episodic encoding.
Impact of emotional salience on episodic memory in attention-deficit/hyperactivity disorder: a functional magnetic resonance imaging study.

PubMed

Krauel, Kerstin; Duzel, Emrah; Hinrichs, Hermann; Santel, Stephanie; Rellum, Thomas; Baving, Lioba

2007-06-15

Patients with attention-deficit/hyperactivity disorder (ADHD) show episodic memory deficits especially in complex memory tasks. We investigated the neural correlates of memory formation in ADHD and their modulation by stimulus salience. We recorded event-related functional magnetic resonance imaging during an episodic memory paradigm with neutral and emotional pictures in 12 male ADHD subjects and 12 healthy adolescents. Emotional salience did significantly augment memory performance in ADHD patients. Successful encoding of neutral pictures was associated with activation of the anterior cingulate cortex (ACC) in healthy adolescents but with activation of the superior parietal lobe (SPL) and precuneus in ADHD patients. Successful encoding of emotional pictures was associated with prefrontal and inferior temporal cortex activation in both groups. Healthy adolescents, moreover, showed deactivation in the inferior parietal lobe. From a pathophysiological point of view, the most striking functional differences between healthy adolescents and ADHD patients were in the ACC and SPL. We suggest that increased SPL activation in ADHD reflected attentional compensation for low ACC activation during the encoding of neutral pictures. The higher salience of emotional stimuli, in contrast, regulated the interplay between ACC and SPL in conjunction with improving memory to the level of healthy adolescents.
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.
Episodic memory for spatial context biases spatial attention.

PubMed

Ciaramelli, Elisa; Lin, Olivia; Moscovitch, Morris

2009-01-01

The study explores the bottom-up attentional consequences of episodic memory retrieval. Individuals studied words (Experiment 1) or pictures (Experiment 2) presented on the left or on the right of the screen. They then viewed studied and new stimuli in the centre of the screen. One-second after the appearance of each stimulus, participants had to respond to a dot presented on the left or on the right of the screen. The dot could follow a stimulus that had been presented, during the study phase, on the same side as the dot (congruent condition), a stimulus that had been presented on the opposite side (incongruent condition), or a new stimulus (neutral condition). Subjects were faster to respond to the dot in the congruent compared to the incongruent condition, with an overall right visual field advantage in Experiment 1. The memory-driven facilitation effect correlated with subjects' re-experiencing of the encoding context (R responses; Experiment 1), but not with their explicit memory for the side of items' presentation (source memory; Experiment 2). The results indicate that memory contents are attended automatically and can bias the deployment of attention. The degree to which memory and attention interact appears related to subjective but not objective indicators of memory strength.
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
Age-related deficits in selective attention during encoding increase demands on episodic reconstruction during context retrieval: An ERP study.

PubMed

James, Taylor; Strunk, Jonathan; Arndt, Jason; Duarte, Audrey

2016-06-01

Previous event-related potential (ERP) and neuroimaging evidence suggests that directing attention toward single item-context associations compared to intra-item features at encoding improves context memory performance and reduces demands on strategic retrieval operations in young and older adults. In everyday situations, however, there are multiple event features competing for our attention. It is not currently known how selectively attending to one contextual feature while attempting to ignore another influences context memory performance and the processes that support successful retrieval in the young and old. We investigated this issue in the current ERP study. Young and older participants studied pictures of objects in the presence of two contextual features: a color and a scene, and their attention was directed to the object's relationship with one of those contexts. Participants made context memory decisions for both attended and unattended contexts and rated their confidence in those decisions. Behavioral results showed that while both groups were generally successful in applying selective attention during context encoding, older adults were less confident in their context memory decisions for attended features and showed greater dependence in context memory accuracy for attended and unattended contextual features (i.e., hyper-binding). ERP results were largely consistent between age groups but older adults showed a more pronounced late posterior negativity (LPN) implicated in episodic reconstruction processes. We conclude that age-related suppression deficits during encoding result in reduced selectivity in context memory, thereby increasing subsequent demands on episodic reconstruction processes when sought after details are not readily retrieved. Copyright © 2016 Elsevier Ltd. All rights reserved.
Auditory cortical function during verbal episodic memory encoding in Alzheimer's disease.

PubMed

Dhanjal, Novraj S; Warren, Jane E; Patel, Maneesh C; Wise, Richard J S

2013-02-01

Episodic memory encoding of a verbal message depends upon initial registration, which requires sustained auditory attention followed by deep semantic processing of the message. Motivated by previous data demonstrating modulation of auditory cortical activity during sustained attention to auditory stimuli, we investigated the response of the human auditory cortex during encoding of sentences to episodic memory. Subsequently, we investigated this response in patients with mild cognitive impairment (MCI) and probable Alzheimer's disease (pAD). Using functional magnetic resonance imaging, 31 healthy participants were studied. The response in 18 MCI and 18 pAD patients was then determined, and compared to 18 matched healthy controls. Subjects heard factual sentences, and subsequent retrieval performance indicated successful registration and episodic encoding. The healthy subjects demonstrated that suppression of auditory cortical responses was related to greater success in encoding heard sentences; and that this was also associated with greater activity in the semantic system. In contrast, there was reduced auditory cortical suppression in patients with MCI, and absence of suppression in pAD. Administration of a central cholinesterase inhibitor (ChI) partially restored the suppression in patients with pAD, and this was associated with an improvement in verbal memory. Verbal episodic memory impairment in AD is associated with altered auditory cortical function, reversible with a ChI. Although these results may indicate the direct influence of pathology in auditory cortex, they are also likely to indicate a partially reversible impairment of feedback from neocortical systems responsible for sustained attention and semantic processing. Copyright © 2012 American Neurological Association.
The effects of attention on age-related relational memory deficits: Evidence from a novel attentional manipulation

PubMed Central

Kim, So-Yeon; Giovanello, Kelly S.

2011-01-01

Healthy aging is often accompanied by episodic memory decline. Prior studies have consistently demonstrated that older adults show disproportionate deficits in relational memory (RM) relative to item memory (IM). Despite rich evidence of an age-related RM deficit, the source of this deficit remains unspecified. One of the most widely investigated factors of age-related RM impairment is a reduction in attentional resources. However, no prior studies have demonstrated that reduced attentional resources are the critical source of age-related RM deficits. Here, we utilized qualitatively different attention tasks, and tested whether reduced attention for relational processing underlies the RM deficit observed in aging. In Experiment 1, we imposed either item-detection or relation-detection attention tasks on young adults during episodic memory encoding, and found that only the concurrent attention task involving relational processing disproportionately impaired RM performance in young adults. Moreover, by ruling out the possible confound of task-difficulty on the disproportionate RM impairment, we further demonstrated that reduced relational attention is a key factor for the age-related RM deficit. In Experiment 2, we replicated the results from Experiment 1 using different materials of stimuli and found that the effect of relational attention on RM is material-general. The results of Experiment 2 also showed that reducing attentional resources for relational processing in young adults strikingly equated their RM performance to that of older adults. Thus, the current study documents the first evidence that reduced attentional resources for relational processing are a critical factor for the relational memory impairment observed in aging. PMID:21707178
Set-relevance determines the impact of distractors on episodic memory retrieval.

PubMed

Kwok, Sze Chai; Shallice, Tim; Macaluso, Emiliano

2014-09-01

We investigated the interplay between stimulus-driven attention and memory retrieval with a novel interference paradigm that engaged both systems concurrently on each trial. Participants encoded a 45-min movie on Day 1 and, on Day 2, performed a temporal order judgment task during fMRI. Each retrieval trial comprised three images presented sequentially, and the task required participants to judge the temporal order of the first and the last images ("memory probes") while ignoring the second image, which was task irrelevant ("attention distractor"). We manipulated the content relatedness and the temporal proximity between the distractor and the memory probes, as well as the temporal distance between two probes. Behaviorally, short temporal distances between the probes led to reduced retrieval performance. Distractors that at encoding were temporally close to the first probe image reduced these costs, specifically when the distractor was content unrelated to the memory probes. The imaging results associated the distractor probe temporal proximity with activation of the right ventral attention network. By contrast, the precuneus was activated for high-content relatedness between distractors and probes and in trials including a short distance between the two memory probes. The engagement of the right ventral attention network by specific types of distractors suggests a link between stimulus-driven attention control and episodic memory retrieval, whereas the activation pattern of the precuneus implicates this region in memory search within knowledge/content-based hierarchies.
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.
Primate Cognition: Attention, Episodic Memory, Prospective Memory, Self-Control, and Metacognition as Examples of Cognitive Control in Nonhuman Primates1

PubMed Central

Menzel, Charles R.; Parrish, Audrey E.; Perdue, Bonnie M.; Sayers, Ken; Smith, J. David; Washburn, David A.

2016-01-01

Primate Cognition is the study of cognitive processes, which represent internal mental processes involved in discriminations, decisions, and behaviors of humans and other primate species. Cognitive control involves executive and regulatory processes that allocate attention, manipulate and evaluate available information (and, when necessary, seek additional information), remember past experiences to plan future behaviors, and deal with distraction and impulsivity when they are threats to goal achievement. Areas of research that relate to cognitive control as it is assessed across species include executive attention, episodic memory, prospective memory, metacognition and self-control. Executive attention refers to the ability to control what sensory stimuli one attends to and how one regulates responses to those stimuli, especially in cases of conflict. Episodic memory refers to memory for personally experienced, autobiographical events. Prospective memory refers to the formation and implementation of future-intended actions, such as remembering what needs to be done later. Metacognition consists of control and monitoring processes that allow individuals to assess what information they have and what information they still need, and then if necessary to seek information. Self-control is a regulatory process whereby individuals forego more immediate or easier to obtain rewards for more delayed or harder to obtain rewards that are objectively more valuable. The behavioral complexity shown by nonhuman primates when given tests to assess these capacities indicates psychological continuities with human cognitive control capacities. However, more research is needed to clarify the proper interpretation of these behaviors with regard to possible cognitive constructs that may underlie such behaviors. PMID:27284790

Long-Term Cognitive Impairment in Kleine-Levin Syndrome

PubMed Central

Uguccioni, Ginevra; Lavault, Sophie; Chaumereuil, Charlotte; Golmard, Jean-Louis; Gagnon, Jean-François; Arnulf, Isabelle

2016-01-01

Study Objectives: In Kleine-Levin syndrome (KLS), episodes of hypersomnia, cognitive, and behavioral disturbances alternate with asymptomatic periods. Because 50% of patients report decreased academic performances, we evaluated their cognitive status during asymptomatic periods, determinants of deficits, and changes during follow-up. Methods: The cognitive assessment during asymptomatic periods in all consecutive patients with typical KLS and healthy controls included the non-verbal intelligence quotient (Raven Progressive Matrices), the Trail Making Test, the Stroop Color-Word Test, the Wechsler Memory Test, verbal fluencies, the Free and Cued Learning Memory Test, and the Rey-Osterreith Complex Figure. Cognitive status was reevaluated after 0.5 to 2 y in 44 patients. Results: At baseline, compared with the 42 controls, the 122 patients with KLS exhibited lower non-verbal intelligence quotient, speed of processing, attention, and reduced retrieval strategies in episodic memory. Higher episode frequency, shorter episode duration, shorter time since last episode, deeper sleep, and megaphagia during episodes predicted impaired memory. The visuoconstructional abilities and non-verbal memory were intact. After a mean follow-up of 1.7 ± 1.0 y, the episode frequency decreased from 4.6 ± 4.8 to 1.7 ± 1.9/y. The logical reasoning and attention improved, the processing speed remained low, and the retrieval strategies in verbal memory further worsened. Conclusions: In this field study, one-third of patients with KLS have long-term cognitive deficits affecting retrieval and processing speed. Cognitive function should be systematically tested in patients with KLS, which appears important to help patients in their academic studies. Citation: Uguccioni G, Lavault S, Chaumereuil C, Golmard JL, Gagnon JF, Arnulf I. Long-term cognitive impairment in kleine-levin syndrome. SLEEP 2016;39(2):429–438. PMID:26414895
Attentional episodes in visual perception

PubMed Central

Wyble, Brad; Potter, Mary C; Bowman, Howard; Nieuwenstein, Mark

2011-01-01

Is one's temporal perception of the world truly as seamless as it appears? This paper presents a computationally motivated theory suggesting that visual attention samples information from temporal episodes (episodic Simultaneous Type/ Serial Token model or eSTST; Wyble et al 2009a). Breaks between these episodes are punctuated by periods of suppressed attention, better known as the attentional blink (Raymond, Shapiro & Arnell 1992). We test predictions from this model and demonstrate that subjects are able to report more letters from a sequence of four targets presented in a dense temporal cluster, than from a sequence of four targets that are interleaved with non-targets. However, this superior report accuracy comes at a cost in impaired temporal order perception. Further experiments explore the dynamics of multiple episodes, and the boundary conditions that trigger episodic breaks. Finally, we contrast the importance of attentional control, limited resources and memory capacity constructs in the model. PMID:21604913
Joint Attention Enhances Visual Working Memory

ERIC Educational Resources Information Center

Gregory, Samantha E. A.; Jackson, Margaret C.

2017-01-01

Joint attention--the mutual focus of 2 individuals on an item--speeds detection and discrimination of target information. However, what happens to that information beyond the initial perceptual episode? To fully comprehend and engage with our immediate environment also requires working memory (WM), which integrates information from second to…
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.
Attention, Imagery and Memory: A Neuromagnetic Investigation

DTIC Science & Technology

1991-10-14

The full complexity of memory processes suggested by the distinctions between short-term and long-term memory , episodic , semantic and declarative...the ;canning of short-term memory . This fol- lows from the fact that bilateral damage to medial temporal cortex results in anterograde amnesia , which...Neural Science AD-A243 859 r󈧅 FINAL TECHNICAL REPORTC Attention, Imagery and Memory 1 March 1988 -30 September 1991 , Q6’i iQ’ UA Dr.~~~~C A..Fel
Memory: Enduring Traces of Perceptual and Reflective Attention

PubMed Central

Chun, Marvin M.; Johnson, Marcia K.

2011-01-01

Attention and memory are typically studied as separate topics, but they are highly intertwined. Here we discuss the relation between memory and two fundamental types of attention: perceptual and reflective. Memory is the persisting consequence of cognitive activities initiated by and/or focused on external information from the environment (perceptual attention) and initiated by and/or focused on internal mental representations (reflective attention). We consider three key questions for advancing a cognitive neuroscience of attention and memory: To what extent do perception and reflection share representational areas? To what extent are the control processes that select, maintain, and manipulate perceptual and reflective information subserved by common areas and networks? During perception and reflection, to what extent are common areas responsible for binding features together to create complex, episodic memories and for reviving them later? Considering similarities and differences in perceptual and reflective attention helps integrate a broad range of findings and raises important unresolved issues. PMID:22099456
Primate cognition: attention, episodic memory, prospective memory, self-control, and metacognition as examples of cognitive control in nonhuman primates.

PubMed

Beran, Michael J; Menzel, Charles R; Parrish, Audrey E; Perdue, Bonnie M; Sayers, Ken; Smith, J David; Washburn, David A

2016-09-01

Primate Cognition is the study of cognitive processes, which represent internal mental processes involved in discriminations, decisions, and behaviors of humans and other primate species. Cognitive control involves executive and regulatory processes that allocate attention, manipulate and evaluate available information (and, when necessary, seek additional information), remember past experiences to plan future behaviors, and deal with distraction and impulsivity when they are threats to goal achievement. Areas of research that relate to cognitive control as it is assessed across species include executive attention, episodic memory, prospective memory, metacognition, and self-control. Executive attention refers to the ability to control what sensory stimuli one attends to and how one regulates responses to those stimuli, especially in cases of conflict. Episodic memory refers to memory for personally experienced, autobiographical events. Prospective memory refers to the formation and implementation of future-intended actions, such as remembering what needs to be done later. Metacognition consists of control and monitoring processes that allow individuals to assess what information they have and what information they still need, and then if necessary to seek information. Self-control is a regulatory process whereby individuals forego more immediate or easier to obtain rewards for more delayed or harder to obtain rewards that are objectively more valuable. The behavioral complexity shown by nonhuman primates when given tests to assess these capacities indicates psychological continuities with human cognitive control capacities. However, more research is needed to clarify the proper interpretation of these behaviors with regard to possible cognitive constructs that may underlie such behaviors. WIREs Cogn Sci 2016, 7:294-316. doi: 10.1002/wcs.1397 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.
Automatic and Controlled Processing in Sentence Recall: The Role of Long-Term and Working Memory

ERIC Educational Resources Information Center

Jefferies, E.; Lambon Ralph, M.A.; Baddeley, A.D.

2004-01-01

Immediate serial recall is better for sentences than word lists presumably because of the additional support that meaningful material receives from long-term memory. This may occur automatically, without the involvement of attention, or may require additional attentionally demanding processing. For example, the episodic buffer model (Baddeley,…
How thinking about what could have been affects how we feel about what was.

PubMed

De Brigard, Felipe; Hanna, Eleanor; St Jacques, Peggy L; Schacter, Daniel L

2018-06-01

Episodic counterfactual thoughts (CFT) and autobiographical memories (AM) involve the reactivation and recombination of episodic memory components into mental simulations. Upon reactivation, memories become labile and prone to modification. Thus, reactivating AM in the context of mentally generating CFT may provide an opportunity for editing processes to modify the content of the original memory. To examine this idea, this paper reports the results of two studies that investigated the effect of reactivating negative and positive AM in the context of either imagining a better (i.e. upward CFT) or a worse (i.e. downward CFT) alternative to an experienced event, as opposed to attentively retrieving the memory without mental modification (i.e. remembering) or no reactivation. Our results suggest that attentive remembering was the best strategy to both reduce the negative affect associated with negative AM, and to prevent the decay of positive affect associated with positive AM. In addition, reactivating positive, but not negative, AM with or without CFT modification reduces the perceived arousal of the original memory over time. Finally, reactivating negative AM in a downward CFT or an attentive remembering condition increases the perceived detail of the original memory over time.
The spectro-contextual encoding and retrieval theory of episodic memory.

PubMed

Watrous, Andrew J; Ekstrom, Arne D

2014-01-01

The spectral fingerprint hypothesis, which posits that different frequencies of oscillations underlie different cognitive operations, provides one account for how interactions between brain regions support perceptual and attentive processes (Siegel etal., 2012). Here, we explore and extend this idea to the domain of human episodic memory encoding and retrieval. Incorporating findings from the synaptic to cognitive levels of organization, we argue that spectrally precise cross-frequency coupling and phase-synchronization promote the formation of hippocampal-neocortical cell assemblies that form the basis for episodic memory. We suggest that both cell assembly firing patterns as well as the global pattern of brain oscillatory activity within hippocampal-neocortical networks represents the contents of a particular memory. Drawing upon the ideas of context reinstatement and multiple trace theory, we argue that memory retrieval is driven by internal and/or external factors which recreate these frequency-specific oscillatory patterns which occur during episodic encoding. These ideas are synthesized into a novel model of episodic memory (the spectro-contextual encoding and retrieval theory, or "SCERT") that provides several testable predictions for future research.
Individual differences in episodic memory abilities predict successful prospective memory output monitoring.

PubMed

Hunter Ball, B; Pitães, Margarida; Brewer, Gene A

2018-02-07

Output monitoring refers to memory for one's previously completed actions. In the context of prospective memory (PM) (e.g., remembering to take medication), failures of output monitoring can result in repetitions and omissions of planned actions (e.g., over- or under-medication). To be successful in output monitoring paradigms, participants must flexibly control attention to detect PM cues as well as engage controlled retrieval of previous actions whenever a particular cue is encountered. The current study examined individual differences in output monitoring abilities in a group of younger adults differing in attention control (AC) and episodic memory (EM) abilities. The results showed that AC ability uniquely predicted successful cue detection on the first presentation, whereas EM ability uniquely predicted successful output monitoring on the second presentation. The current study highlights the importance of examining external correlates of PM abilities and contributes to the growing body of research on individual differences in PM.
The posterior parietal paradox: Why do functional magnetic resonance imaging and lesion studies on episodic memory produce conflicting results?

PubMed

Schoo, L A; van Zandvoort, M J E; Biessels, G J; Kappelle, L J; Postma, A; de Haan, E H F

2011-03-01

Recent functional magnetic resonance imaging (fMRI) studies addressing healthy subjects point towards posterior parietal cortex (PPC) involvement in episodic memory tasks. This is noteworthy, since neuropsychological studies usually do not connect parietal lesions to episodic memory impairments. Therefore an inventory of the possible factors behind this apparent paradox is warranted. This review compared fMRI studies which demonstrated PPC activity in episodic memory tasks, with findings with studies of patients with PPC lesions. A systematic evaluation of possible explanations for the posterior parietal paradox indicates that PPC activation in fMRI studies does not appear to be attributable to confounding cognitive/psychomotor processes, such as button pressing or stimulus processing. What may be of more importance is the extent to which an episodic memory task loads on three closely related cognitive processes: effort and attention, self-related activity, and scene and image construction. We discuss to what extent these cognitive processes can account for the paradox between lesion and fMRI results. They are strongly intertwined with the episodic memory and may critically determine in how far the PPC plays a role in a given memory task. Future patient studies might profit from specifically taking these cognitive factors into consideration in the task design. ©2010 The British Psychological Society.
Episodic memory impairment in Addison's disease: results from a telephonic cognitive assessment.

PubMed

Henry, Michelle; Thomas, Kevin G F; Ross, Ian L

2014-06-01

Patients with Addison's disease frequently self-report memory and attention difficulties, even when on standard replacement therapy. However, few published studies examine, using objective measures and assessing across multiple domains, the cognitive functioning of Addison's disease patients relative to healthy controls. The primary aim of this study was to investigate whether the previously reported subjective cognitive deficits in Addison's disease are confirmed by objective measures. Conducting comprehensive neuropsychological assessments of patients with relatively rare clinical disorders, such as Addison's disease, is challenging because access to those patients is often limited, and because their medical condition might prevent extended testing sessions. Brief telephonic cognitive assessments are a useful tool in such circumstances. Hence, we administered the Brief Test of Adult Cognition by Telephone to 27 Addison's disease patients and 27 matched healthy controls. The instrument provides objective assessment of episodic memory, working memory, executive functioning, reasoning, and speed of processing. Statistical analyses confirmed that, as expected, patients performed significantly more poorly than controls on the episodic memory subtest. There were, however, no significant between-group differences on the attention, executive functioning, reasoning, and speed of processing subtests. Furthermore, patients with a longer duration of illness performed more poorly across all domains of cognition. We conclude that, for Addison's disease patients, previously reported subjective cognitive deficits are matched by objective impairment, but only in the domain of episodic memory. Future research might investigate (a) whether these memory deficits are material-specific (i.e., whether non-verbal memory is also affected), and (b) the neurobiological mechanisms underlying these deficits.
Semantic congruence enhances memory of episodic associations: role of theta oscillations.

PubMed

Atienza, Mercedes; Crespo-Garcia, Maite; Cantero, Jose L

2011-01-01

Growing evidence suggests that theta oscillations play a crucial role in episodic encoding. The present study evaluates whether changes in electroencephalographic theta source dynamics mediate the positive influence of semantic congruence on incidental associative learning. Here we show that memory for episodic associations (face-location) is more accurate when studied under semantically congruent contexts. However, only participants showing RT priming effect in a conceptual priming test (priming group) also gave faster responses when recollecting source information of semantically congruent faces as compared with semantically incongruent faces. This improved episodic retrieval was positively correlated with increases in theta power during the study phase mainly in the bilateral parahippocampal gyrus, left superior temporal gyrus, and left lateral posterior parietal lobe. Reconstructed signals from the estimated sources showed higher theta power for congruent than incongruent faces and also for the priming than the nonpriming group. These results are in agreement with the attention to memory model. Besides directing top-down attention to goal-relevant semantic information during encoding, the dorsal parietal lobe may also be involved in redirecting attention to bottom-up-driven memories thanks to connections between the medial-temporal and the left ventral parietal lobe. The latter function can either facilitate or interfere with encoding of face-location associations depending on whether they are preceded by semantically congruent or incongruent contexts, respectively, because only in the former condition retrieved representations related to the cue and the face are both coherent with the person identity and are both associated with the same location.
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.
Attention, memory, visuoconstructive, and executive task performance in adolescents with anxiety disorders: a case-control community study.

PubMed

Jarros, Rafaela Behs; Salum, Giovanni Abrahão; Silva, Cristiano Tschiedel Belem da; Toazza, Rudineia; Becker, Natália; Agranonik, Marilyn; Salles, Jerusa Fumagalli de; Manfro, Gisele Gus

2017-01-01

The aim of the present study was to assess children and adolescents with mild and severe anxiety disorders for their performance in attention, verbal episodic memory, working memory, visuoconstructive skills, executive functions, and cognitive global functioning and conduct comparative analyses with the performance of children free from anxiety disorders. Our sample comprised 68 children and adolescents aged 10 to 17 years (41 with current diagnoses of anxiety disorders and 27 controls) selected from a larger cross-sectional community sample of adolescents. Children and adolescents with anxiety disorders were categorized into two groups on the basis of anxiety severity (mild or severe). All participants underwent a neuropsychological assessment battery to evaluate attention, verbal episodic memory, working memory, visuoconstructive skills, and executive and cognitive functions. No differences were found in any neuropsychological tests, with the single exception that the group with mild anxiety had better performance on the Digit Span backward test compared to subjects with severe anxiety and to controls (p = 0.041; η2 = 0.11). Not only might anxiety disorders spare main cognitive functions during adolescence, they may even enhance certain working memory processes.
Left Posterior Parietal Cortex Participates in Both Task Preparation and Episodic Retrieval

PubMed Central

Phillips, Jeffrey S.; Velanova, Katerina; Wolk, David A.; Wheeler, Mark E.

2012-01-01

Optimal memory retrieval depends not only on the fidelity of stored information, but also on the attentional state of the subject. Factors such as mental preparedness to engage in stimulus processing can facilitate or hinder memory retrieval. The current study used functional magnetic resonance imaging (fMRI) to distinguish preparatory brain activity before episodic and semantic retrieval tasks from activity associated with retrieval itself. A catch-trial imaging paradigm permitted separation of neural responses to preparatory task cues and memory probes. Episodic and semantic task preparation engaged a common set of brain regions, including the bilateral intraparietal sulcus (IPS), left fusiform gyrus (FG), and the pre-supplementary motor area (pre-SMA). In the subsequent retrieval phase, the left IPS was among a set of frontoparietal regions that responded differently to old and new stimuli. In contrast, the right IPS responded to preparatory cues with little modulation during memory retrieval. The findings support a strong left-lateralization of retrieval success effects in left parietal cortex, and further indicate that left IPS performs operations that are common to both task preparation and memory retrieval. Such operations may be related to attentional control, monitoring of stimulus relevance, or retrieval. PMID:19285142
Efficacy of a Computer-Assisted Cognitive Rehabilitation Intervention in Relapsing-Remitting Multiple Sclerosis Patients: A Multicenter Randomized Controlled Trial

PubMed Central

Kosmidis, Mary H.; Zampakis, Petros; Malefaki, Sonia; Ntoskou, Katerina; Nousia, Anastasia; Bakirtzis, Christos; Papathanasopoulos, Panagiotis

2017-01-01

Cognitive impairment is frequently encountered in multiple sclerosis (MS) affecting between 40–65% of individuals, irrespective of disease duration and severity of physical disability. In the present multicenter randomized controlled trial, fifty-eight clinically stable RRMS patients with mild to moderate cognitive impairment and relatively low disability status were randomized to receive either computer-assisted (RehaCom) functional cognitive training with an emphasis on episodic memory, information processing speed/attention, and executive functions for 10 weeks (IG; n = 32) or standard clinical care (CG; n = 26). Outcome measures included a flexible comprehensive neuropsychological battery of tests sensitive to MS patient deficits and feedback regarding personal benefit gained from the intervention on four verbal questions. Only the IG group showed significant improvements in verbal and visuospatial episodic memory, processing speed/attention, and executive functioning from pre - to postassessment. Moreover, the improvement obtained on attention was retained over 6 months providing evidence on the long-term benefits of this intervention. Group by time interactions revealed significant improvements in composite cognitive domain scores in the IG relative to the demographically and clinically matched CG for verbal episodic memory, processing speed, verbal fluency, and attention. Treated patients rated the intervention positively and were more confident about their cognitive abilities following treatment. PMID:29463950
The Maintenance of Cross-Domain Associations in the Episodic Buffer

ERIC Educational Resources Information Center

Langerock, Naomi; Vergauwe, Evie; Barrouillet, Pierre

2014-01-01

The episodic buffer has been described as a structure of working memory capable of maintaining multimodal information in an integrated format. Although the role of the episodic buffer in binding features into objects has received considerable attention, several of its characteristics have remained rather underexplored. This is the case for its…
Memory: enduring traces of perceptual and reflective attention.

PubMed

Chun, Marvin M; Johnson, Marcia K

2011-11-17

Attention and memory are typically studied as separate topics, but they are highly intertwined. Here we discuss the relation between memory and two fundamental types of attention: perceptual and reflective. Memory is the persisting consequence of cognitive activities initiated by and/or focused on external information from the environment (perceptual attention) and initiated by and/or focused on internal mental representations (reflective attention). We consider three key questions for advancing a cognitive neuroscience of attention and memory: to what extent do perception and reflection share representational areas? To what extent are the control processes that select, maintain, and manipulate perceptual and reflective information subserved by common areas and networks? During perception and reflection, to what extent are common areas responsible for binding features together to create complex, episodic memories and for reviving them later? Considering similarities and differences in perceptual and reflective attention helps integrate a broad range of findings and raises important unresolved issues. Copyright © 2011 Elsevier Inc. All rights reserved.

Working memory deficits in boys with attention deficit/hyperactivity disorder (ADHD): An examination of orthographic coding and episodic buffer processes.

PubMed

Alderson, R Matt; Kasper, Lisa J; Patros, Connor H G; Hudec, Kristen L; Tarle, Stephanie J; Lea, Sarah E

2015-01-01

The episodic buffer component of working memory was examined in children with attention deficit/hyperactivity disorder (ADHD) and typically developing peers (TD). Thirty-two children (ADHD = 16, TD = 16) completed three versions of a phonological working memory task that varied with regard to stimulus presentation modality (auditory, visual, or dual auditory and visual), as well as a visuospatial task. Children with ADHD experienced the largest magnitude working memory deficits when phonological stimuli were presented via a unimodal, auditory format. Their performance improved during visual and dual modality conditions but remained significantly below the performance of children in the TD group. In contrast, the TD group did not exhibit performance differences between the auditory- and visual-phonological conditions but recalled significantly more stimuli during the dual-phonological condition. Furthermore, relative to TD children, children with ADHD recalled disproportionately fewer phonological stimuli as set sizes increased, regardless of presentation modality. Finally, an examination of working memory components indicated that the largest magnitude between-group difference was associated with the central executive. Collectively, these findings suggest that ADHD-related working memory deficits reflect a combination of impaired central executive and phonological storage/rehearsal processes, as well as an impaired ability to benefit from bound multimodal information processed by the episodic buffer.
Memory-guided attention in the anterior thalamus.

PubMed

Leszczyński, Marcin; Staudigl, Tobias

2016-07-01

The anterior thalamus is densely connected with both the hippocampus and the prefrontal cortex. It is known to play a role in learning and episodic memory. Given its connectivity profile with the prefrontal cortex, it may also be expected to contribute to executive functions. Recent studies in both rodents and humans add to our understanding of anterior thalamic function, suggesting that it is a key region for allocating attention. We discuss the convergence between studies in rodents and humans, both of which imply that the anterior thalamus may play a key role in memory-guided attention. We suggest that efficient allocation of attention to memory representations requires interaction between the memory-related hippocampal and the attention related fronto-parietal networks. We further propose that the anterior thalamus is a hub that connects and modulates both systems. Copyright © 2016 Elsevier Ltd. All rights reserved.
Attentional Imbalances Following Head Injury

DTIC Science & Technology

1988-05-30

on recent memory , the patient’s basic fund of knowledge ( semantic memory ) and remote memory for events ( episodic memory ) were both impaired. For e...are notable for problems caused by poor memory , inflexibility, and concreteness. These problems are most severe when they interact with linguistic...demands. It is worth noting that memory problems were accompanied by confabulation (hen the patient first entered the program. In addition to the effects
Beneficial effects of glycine (bioglycin) on memory and attention in young and middle-aged adults.

PubMed

File, S E; Fluck, E; Fernandes, C

1999-12-01

The N-methyl D-aspartate receptor complex is involved in the mechanism of long-term potentiation, which is thought to be the biological basis of learning and memory. This complex can be manipulated in a number of ways, one of which is through the strychnine-insensitive glycine receptor coagonist site. The effects of Bioglycin(Konapharma, Pratteln, Switzerland), a biologically active form of the amino acid glycine, were therefore studied in healthy students (mean age, 20.7 years) and middle-aged men (mean age, 58.9 years) with tests that measured attention, memory and mood, using a double-blind, randomized, crossover design. Compared with the young group, the middle-aged group had significantly poorer verbal episodic memory, focused, divided, and sustained attention; they also differed in their subjective responses at the end of testing. Bioglycin significantly improved retrieval from episodic memory in both the young and the middle-aged groups, but it did not affect focused or divided attention. However, the middle-aged men significantly benefited from Bioglycin in the sustained-attention task. The effects of Bioglycin differed from those of other cognitive enhancers in that it was without stimulant properties or significant effects on mood, and it primarily improved memory rather than attention. It is likely to be of benefit in young or older people in situations where high retrieval of information is needed or when performance is impaired by jet lag, shift work, or disrupted sleep. It may also benefit the impaired retrieval shown in patients with schizophrenia, Parkinson's disease, and Huntington's disease.
The effects of divided attention on implicit and explicit memory performance.

PubMed

Schmitter-Edgecombe, M

1996-03-01

This study explored the nature of the relationship between attention available at learning and subsequent implicit and explicit memory performance. One hundred neurologically normal subjects rated their liking of target words on a five-point scale. Half of the subjects completed the word-rating task in a full attention condition and the other half performed the task in a divided attention condition. Following administration of the word-rating task, all subjects completed five memory tests, three implicit (category association, tachistoscopic identification, and perceptual clarification) and two explicit (semantic-cued recall and graphemic-cued recall), each bearing on a different subset of the list of previously presented target words. The results revealed that subjects in the divided attention condition performed significantly more poorly than subjects in the full attention condition on the explicit memory measures. In contrast, there were no significant group differences in performance on the implicit memory measures. These findings suggest that the attention to an episode that is necessary to produce later explicit memory may differ from that necessary to produce unconscious influences. The relationship between implicit memory, neurologic injury and automatic processes is discussed.
Is the Binding of Visual Features in Working Memory Resource-Demanding?

ERIC Educational Resources Information Center

Allen, Richard J.; Baddeley, Alan D.; Hitch, Graham J.

2006-01-01

The episodic buffer component of working memory is assumed to play a role in the binding of features into chunks. A series of experiments compared memory for arrays of colors or shapes with memory for bound combinations of these features. Demanding concurrent verbal tasks were used to investigate the role of general attentional processes,…
Contribution of N-methyl-D-aspartate receptors to attention and episodic spatial memory during senescence

PubMed Central

Guidi, Michael; Rani, Asha; Karic, Semir; Severance, Barrett; Kumar, Ashok; Foster, Thomas C.

2015-01-01

A decrease in N-methyl-D-aspartate receptor (NMDAR) function is associated with age-related cognitive impairments. However, NMDAR antagonists are prescribed for cognitive decline associated with age-related neurodegenerative disease, raising questions as to the role of NMDAR activity in cognitive function during aging. The current studies examined effects of NMDAR blockade on cognitive task that are sensitive to aging. Young and middle-age rats were trained on the five-choice serial reaction time task (5-CSRTT) and challenged with MK-801 (0.025, 0.05, and 0.1 mg/kg or vehicle). Attention deficits were apparent in middle-age and performance of young and middle-age rats was enhanced for low doses of MK-801 (0.025 and 0.05). The beneficial effects on attention were reversed by the highest dose of MK-801. Older animals exhibited a delay-dependent impairment of episodic spatial memory examined on a delayed-matching to place water maze task. Similarly, a low dose of MK-801 (0.05 mg/kg) impaired performance with increasing delay and aged animals were more susceptible to disruption by NMDAR blockade. Despite MK-801 impairment of episodic spatial memory, MK-801 had minimal effects on spatial reference memory. Our results confirm that NMDARs contribute to rapidly acquired and flexible spatial memory and support the idea that a decline in NMDAR function contributes to the age-related impairments in cognition. PMID:26234588
Contribution of N-methyl-D-aspartate receptors to attention and episodic spatial memory during senescence.

PubMed

Guidi, Michael; Rani, Asha; Karic, Semir; Severance, Barrett; Kumar, Ashok; Foster, Thomas C

2015-11-01

A decrease in N-methyl-D-aspartate receptor (NMDAR) function is associated with age-related cognitive impairments. However, NMDAR antagonists are prescribed for cognitive decline associated with age-related neurodegenerative disease, raising questions as to the role of NMDAR activity in cognitive function during aging. The current studies examined effects of NMDAR blockade on cognitive task that are sensitive to aging. Young and middle-age rats were trained on the five-choice serial reaction time task (5-CSRTT) and challenged with MK-801 (0.025, 0.05, and 0.1mg/kg or vehicle). Attention deficits were apparent in middle-age and performance of young and middle-age rats was enhanced for low doses of MK-801 (0.025 and 0.05). The beneficial effects on attention were reversed by the highest dose of MK-801. Older animals exhibited a delay-dependent impairment of episodic spatial memory examined on a delayed-matching to place water maze task. Similarly, a low dose of MK-801 (0.05mg/kg) impaired performance with increasing delay and aged animals were more susceptible to disruption by NMDAR blockade. Despite MK-801 impairment of episodic spatial memory, MK-801 had minimal effects on spatial reference memory. Our results confirm that NMDARs contribute to rapidly acquired and flexible spatial memory and support the idea that a decline in NMDAR function contributes to the age-related impairments in cognition. Copyright © 2015 Elsevier Inc. All rights reserved.
Concealed semantic and episodic autobiographical memory electrified.

PubMed

Ganis, Giorgio; Schendan, Haline E

2012-01-01

Electrophysiology-based concealed information tests (CIT) try to determine whether somebody possesses concealed information about a crime-related item (probe) by comparing event-related potentials (ERPs) between this item and comparison items (irrelevants). Although the broader field is sometimes referred to as "memory detection," little attention has been paid to the precise type of underlying memory involved. This study begins addressing this issue by examining the key distinction between semantic and episodic memory in the autobiographical domain within a CIT paradigm. This study also addresses the issue of whether multiple repetitions of the items over the course of the session habituate the brain responses. Participants were tested in a 3-stimulus CIT with semantic autobiographical probes (their own date of birth) and episodic autobiographical probes (a secret date learned just before the study). Results dissociated these two memory conditions on several ERP components. Semantic probes elicited a smaller frontal N2 than episodic probes, consistent with the idea that the frontal N2 decreases with greater pre-existing knowledge about the item. Likewise, semantic probes elicited a smaller central N400 than episodic probes. Semantic probes also elicited a larger P3b than episodic probes because of their richer meaning. In contrast, episodic probes elicited a larger late positive complex (LPC) than semantic probes, because of the recent episodic memory associated with them. All these ERPs showed a difference between probes and irrelevants in both memory conditions, except for the N400, which showed a difference only in the semantic condition. Finally, although repetition affected the ERPs, it did not reduce the difference between probes and irrelevants. These findings show that the type of memory associated with a probe has both theoretical and practical importance for CIT research.
Concealed semantic and episodic autobiographical memory electrified

PubMed Central

Ganis, Giorgio; Schendan, Haline E.

2013-01-01

Electrophysiology-based concealed information tests (CIT) try to determine whether somebody possesses concealed information about a crime-related item (probe) by comparing event-related potentials (ERPs) between this item and comparison items (irrelevants). Although the broader field is sometimes referred to as “memory detection,” little attention has been paid to the precise type of underlying memory involved. This study begins addressing this issue by examining the key distinction between semantic and episodic memory in the autobiographical domain within a CIT paradigm. This study also addresses the issue of whether multiple repetitions of the items over the course of the session habituate the brain responses. Participants were tested in a 3-stimulus CIT with semantic autobiographical probes (their own date of birth) and episodic autobiographical probes (a secret date learned just before the study). Results dissociated these two memory conditions on several ERP components. Semantic probes elicited a smaller frontal N2 than episodic probes, consistent with the idea that the frontal N2 decreases with greater pre-existing knowledge about the item. Likewise, semantic probes elicited a smaller central N400 than episodic probes. Semantic probes also elicited a larger P3b than episodic probes because of their richer meaning. In contrast, episodic probes elicited a larger late positive complex (LPC) than semantic probes, because of the recent episodic memory associated with them. All these ERPs showed a difference between probes and irrelevants in both memory conditions, except for the N400, which showed a difference only in the semantic condition. Finally, although repetition affected the ERPs, it did not reduce the difference between probes and irrelevants. These findings show that the type of memory associated with a probe has both theoretical and practical importance for CIT research. PMID:23355816
[Effects of the association of sulbutiamine with an acetylcholinesterase inhibitor in early stage and moderate Alzheimer disease].

PubMed

Ollat, H; Laurent, B; Bakchine, S; Michel, B-F; Touchon, J; Dubois, B

2007-01-01

The efficacy of the inhibitors of acetylcholinesterase in Alzheimer's Disease (AD) is moderated and some patients do not respond to these treatments. Sulbutiamine potentializes cholinergic and glutamatergic transmissions, mainly in hippocampus and prefrontal cortex. This multicentric, randomized and double-blind trial evaluates the effects of the association of sulbutiamine to an anticholinesterasic drug in cognitive functions in patients with AD at an early stage (episodic memory, working memory, executive functions, attention). Patients had first donepezil (D) or sulbutiamine (S) during three months. During this period, only attention improved in both groups. During the three following months, a placebo (P) in patients D and donepezil in patients S were added. Compared to entry results, episodic memory decreased in group D + P but improved in group S + D. At the same time the improvement of attention persisted in both groups. Daylife activities only improved in group S + D. In conclusion sulbutiamine can be an adjuvant to treatment in early stage and moderate AD by anticholinesterasic drugs.
Executive functions deficit in mild cognitive impairment.

PubMed

Traykov, Latchezar; Raoux, Nadine; Latour, Florence; Gallo, Livia; Hanon, Olivier; Baudic, Sophie; Bayle, Catherine; Wenisch, Emilie; Remy, Philippe; Rigaud, Anne-Sophie

2007-12-01

To investigate whether patients diagnosed with amnestic mild cognitive impairment (MCI) have also impairment in attention/executive functions, and therefore to clarify whether all subcomponents of executive control are equally affected in MCI. MCI refers to the transitional state between normal aging and dementia. Amnestic MCI is characterized by impaired episodic memory, although subtle impairment of executive functions has been noted on neuropsychologic tests. We investigated 20 MCI patients and 20 normal controls using episodic memory, attention/executive functions, language, and praxis tests. MCI patients had significantly lower scores on all measures of the Free and Cued Selective Reminding Test (P<0.05 to 0.01) than controls. Furthermore, MCI had a greater number of perseverations (P<0.01) on Modified Card Sorting Test and the lowest performance on the Stroop Test (P<0.02). Our findings showed impairment in episodic memory performance in MCI as compared with that of controls. In addition, MCI patients had problems with response inhibition, switching, and cognitive flexibility, which encompass various aspects of executive functions. This suggests that MCI may be identified by using a more detailed procedure for the assessment of cognitive decline than the evaluation of memory alone.
A Place for Every Event and Every Event in Its Place: Memory for Locations and Activities by 4-Year-Old Children

ERIC Educational Resources Information Center

Bauer, Patricia J.; Stewart, Rebekah; White, Elizabeth A.; Larkina, Marina

2016-01-01

Episodic memories are of specific events and experiences associated with particular times and places. Whereas memory for the temporal aspects of past events has been a focus of research attention, memory for the location in which events were experienced has been less fully investigated. The limited developmental research suggests that…
Relationship between working hours and power of attention, memory, fatigue, depression and self-efficacy one year after diagnosis of clinically isolated syndrome and relapsing remitting multiple sclerosis.

PubMed

Jongen, Peter Joseph; Wesnes, Keith; van Geel, Björn; Pop, Paul; Sanders, Evert; Schrijver, Hans; Visser, Leo H; Gilhuis, H Jacobus; Sinnige, Ludovicus G; Brands, Augustina M

2014-01-01

The role of cognitive domain dysfunction with respect to vocational changes in persons with Clinically Isolated Syndrome (CIS) and early Relapsing Remitting Multiple Sclerosis (eRRMS) is insufficiently known. We investigated thirty-three patients--14 CIS, 19 eRRMS -, mean (standard deviation [SD]) time since diagnosis 13.5 (4.8) months and mean (SD) Expanded Disability Status Scale (EDSS) score 1.3 (1.1). Patients were assessed on the CDR System, a set of automated tests of cognitive function, which yielded scores for Power of Attention (ms), Continuity of Attention (#), Working Memory (SI), Episodic Memory (#) and Speed of Memory (ms). Work-related items and the confounding variables fatigue, depression, disease impact and self-efficacy, were assessed by self-report questionnaires. Patients had poorer Power of Attention compared to normative data (1187 [161.5] vs. 1070 [98.6]; P<0.0001) and slower Speed of Memory (4043 [830.6]) vs. 2937 [586.1]; P<0.0001). Power of Attention (Pearson r = -0.42; P<0.04), Working Memory (r = 0.42; P<0.04) and depression r = -0.41; P<0.05) correlated with number of days worked per week. Fatigue (r = -0.56; P<0.005), self-efficacy (r = 0.56; P<0.005) and disease impact (r = -0.46; P<0.05) correlated with number of hours worked per week. Persons who wished to work less had poorer Power of Attention (1247 vs. 1116 ms; P<0.02), those who wished to change job had poorer Episodic Memory (1.35 vs. 1.57; p<0.03). People who reduced working hours within 12 months after diagnosis had higher fatigue and disease impact, and lower self-efficacy. The findings of this pilot study indicate that one year after the diagnosis of CIS and RRMS Power of Attention and Speed of Memory are reduced, that Power of Attention and Memory are associated with a capability of working less hours, and that fatigue, depression and disease impact may negatively, and self-efficacy positively affect working hours.
Hearing loss is negatively related to episodic and semantic long-term memory but not to short-term memory.

PubMed

Rönnberg, Jerker; Danielsson, Henrik; Rudner, Mary; Arlinger, Stig; Sternäng, Ola; Wahlin, Ake; Nilsson, Lars-Göran

2011-04-01

To test the relationship between degree of hearing loss and different memory systems in hearing aid users. Structural equation modeling (SEM) was used to study the relationship between auditory and visual acuity and different cognitive and memory functions in an age-hetereogenous subsample of 160 hearing aid users without dementia, drawn from the Swedish prospective cohort aging study known as Betula (L.-G. Nilsson et al., 1997). Hearing loss was selectively and negatively related to episodic and semantic long-term memory (LTM) but not short-term memory (STM) performance. This held true for both ears, even when age was accounted for. Visual acuity alone, or in combination with auditory acuity, did not contribute to any acceptable SEM solution. The overall relationships between hearing loss and memory systems were predicted by the ease of language understanding model (J. Rönnberg, 2003), but the exact mechanisms of episodic memory decline in hearing aid users (i.e., mismatch/disuse, attentional resources, or information degradation) remain open for further experiments. The hearing aid industry should strive to design signal processing algorithms that are cognition friendly.
Memory-guided selective attention: Single experiences with conflict have long-lasting effects on cognitive control.

PubMed

Brosowsky, Nicholaus P; Crump, Matthew J C

2018-05-17

Adjustments in cognitive control, as measured by congruency sequence effects, are thought to be influenced by both external stimuli and internal goals. However, this dichotomy has often overshadowed the potential contribution of past experience stored in memory. Here, we examine the role of long-term episodic memory in guiding selective attention. Our aim was to demonstrate new evidence that selective attention can be modulated by long-term retrieval of stimulus-specific attentional control settings. All the experiments used a modified flanker task involving multiple unique stimuli. Critically, each stimulus was only presented twice during the experiment: first as a prime, and second as a probe. Experiments 1 and 2 varied the number of intervening trials between prime and probe and manipulated the amount of conflict using a secondary task. Experiment 3 ensured that specific colors assigned to prime stimuli were not repeated when presented as probes. Across both Experiments 1 and 2, we consistently found smaller congruency effects on probe trials when its associated prime trial was incongruent compared with congruent, demonstrating long-term congruency sequence effects. However, Experiment 3 showed no evidence for long-term effects. These findings suggest long-term preservation of selective attention processing at the episodic level, and implicate a role for memory in updating cognitive control. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Correlation between Inter-Blink Interval and Episodic Encoding during Movie Watching.

PubMed

Shin, Young Seok; Chang, Won-du; Park, Jinsick; Im, Chang-Hwan; Lee, Sang In; Kim, In Young; Jang, Dong Pyo

2015-01-01

Human eye blinking is cognitively suppressed to minimize loss of visual information for important real-world events. Despite the relationship between eye blinking and cognitive state, the effect of eye blinks on cognition in real-world environments has received limited research attention. In this study, we focused on the temporal pattern of inter-eye blink interval (IEBI) during movie watching and investigated its relationship with episodic memory. As a control condition, 24 healthy subjects watched a nature documentary that lacked a specific story line while electroencephalography was performed. Immediately after viewing the movie, the subjects were asked to report its most memorable scene. Four weeks later, subjects were asked to score 32 randomly selected scenes from the movie, based on how much they were able to remember and describe. The results showed that the average IEBI was significantly longer during the movie than in the control condition. In addition, the significant increase in IEBI when watching a movie coincided with the most memorable scenes of the movie. The results suggested that the interesting episodic narrative of the movie attracted the subjects' visual attention relative to the documentary clip that did not have a story line. In the episodic memory test executed four weeks later, memory performance was significantly positively correlated with IEBI (p<0.001). In summary, IEBI may be a reliable bio-marker of the degree of concentration on naturalistic content that requires visual attention, such as a movie.
Correlation between Inter-Blink Interval and Episodic Encoding during Movie Watching

PubMed Central

Shin, Young Seok; Chang, Won-du; Park, Jinsick; Im, Chang-Hwan; Lee, Sang In; Kim, In Young; Jang, Dong Pyo

2015-01-01

Human eye blinking is cognitively suppressed to minimize loss of visual information for important real-world events. Despite the relationship between eye blinking and cognitive state, the effect of eye blinks on cognition in real-world environments has received limited research attention. In this study, we focused on the temporal pattern of inter-eye blink interval (IEBI) during movie watching and investigated its relationship with episodic memory. As a control condition, 24 healthy subjects watched a nature documentary that lacked a specific story line while electroencephalography was performed. Immediately after viewing the movie, the subjects were asked to report its most memorable scene. Four weeks later, subjects were asked to score 32 randomly selected scenes from the movie, based on how much they were able to remember and describe. The results showed that the average IEBI was significantly longer during the movie than in the control condition. In addition, the significant increase in IEBI when watching a movie coincided with the most memorable scenes of the movie. The results suggested that the interesting episodic narrative of the movie attracted the subjects’ visual attention relative to the documentary clip that did not have a story line. In the episodic memory test executed four weeks later, memory performance was significantly positively correlated with IEBI (p<0.001). In summary, IEBI may be a reliable bio-marker of the degree of concentration on naturalistic content that requires visual attention, such as a movie. PMID:26529091
Effects of acute tryptophan depletion on memory, attention and executive functions: a systematic review.

PubMed

Mendelsohn, Daniel; Riedel, Wim J; Sambeth, Anke

2009-06-01

The serotonergic system is implicated in the regulation of mood and cognition. Acute tryptophan depletion (ATD) is an experimental procedure for lowering central serotonin levels. Here, the effects of ATD on psychomotor processing, declarative memory, working memory, executive functions and attention are discussed. The most robust finding is that ATD impairs the consolidation of episodic memory for verbal information. Semantic memory appears to be unaffected by ATD although a limited variety of tasks examined effects in this domain. Similarly, evidence suggests ATD does not influence verbal, spatial and affective working memory. Most studies investigating effects on executive functions have produced non-specific or negative findings. In terms of attention, ATD either does not affect or may improve focused attention and ATD likely does not impact sustained and divided attention or attentional set-shifting. Although ATD is known to affect mood in certain vulnerable populations, the effects of ATD on cognition in non-vulnerable participants are independent of mood changes. Suggestions for future directions and implications for psychiatric illnesses are discussed.
Attention and working memory: two basic mechanisms for constructing temporal experiences

PubMed Central

Marchetti, Giorgio

2014-01-01

Various kinds of observations show that the ability of human beings to both consciously relive past events – episodic memory – and conceive future events, entails an active process of construction. This construction process also underpins many other important aspects of conscious human life, such as perceptions, language, and conscious thinking. This article provides an explanation of what makes the constructive process possible and how it works. The process mainly relies on attentional activity, which has a discrete and periodic nature, and working memory, which allows for the combination of discrete attentional operations. An explanation is also provided of how past and future events are constructed. PMID:25177305

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.
Amyloid-independent functional neural correlates of episodic memory in amnestic mild cognitive impairment.

PubMed

Seo, Eun Hyun; Choo, I L Han

2016-06-01

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

PubMed

Christensen, Thomas A; Almryde, Kyle R; Fidler, Lesley J; Lockwood, Julie L; Antonucci, Sharon M; Plante, Elena

2012-01-01

Attention is crucial for encoding information into memory, and current dual-process models seek to explain the roles of attention in both recollection memory and incidental-perceptual memory processes. The present study combined an incidental memory paradigm with event-related functional MRI to examine the effect of attention at encoding on the subsequent neural activation associated with unintended perceptual memory for spoken words. At encoding, we systematically varied attention levels as listeners heard a list of single English nouns. We then presented these words again in the context of a recognition task and assessed the effect of modulating attention at encoding on the BOLD responses to words that were either attended strongly, weakly, or not heard previously. MRI revealed activity in right-lateralized inferior parietal and prefrontal regions, and positive BOLD signals varied with the relative level of attention present at encoding. Temporal analysis of hemodynamic responses further showed that the time course of BOLD activity was modulated differentially by unintentionally encoded words compared to novel items. Our findings largely support current models of memory consolidation and retrieval, but they also provide fresh evidence for hemispheric differences and functional subdivisions in right frontoparietal attention networks that help shape auditory episodic recall.
Modulating the Focus of Attention for Spoken Words at Encoding Affects Frontoparietal Activation for Incidental Verbal Memory

PubMed Central

Christensen, Thomas A.; Almryde, Kyle R.; Fidler, Lesley J.; Lockwood, Julie L.; Antonucci, Sharon M.; Plante, Elena

2012-01-01

Attention is crucial for encoding information into memory, and current dual-process models seek to explain the roles of attention in both recollection memory and incidental-perceptual memory processes. The present study combined an incidental memory paradigm with event-related functional MRI to examine the effect of attention at encoding on the subsequent neural activation associated with unintended perceptual memory for spoken words. At encoding, we systematically varied attention levels as listeners heard a list of single English nouns. We then presented these words again in the context of a recognition task and assessed the effect of modulating attention at encoding on the BOLD responses to words that were either attended strongly, weakly, or not heard previously. MRI revealed activity in right-lateralized inferior parietal and prefrontal regions, and positive BOLD signals varied with the relative level of attention present at encoding. Temporal analysis of hemodynamic responses further showed that the time course of BOLD activity was modulated differentially by unintentionally encoded words compared to novel items. Our findings largely support current models of memory consolidation and retrieval, but they also provide fresh evidence for hemispheric differences and functional subdivisions in right frontoparietal attention networks that help shape auditory episodic recall. PMID:22144982
Better together: Left and right hemisphere engagement to reduce age-related memory loss.

PubMed

Brambilla, Michela; Manenti, Rosa; Ferrari, Clarissa; Cotelli, Maria

2015-10-15

Episodic memory is a cognitive function that appears more susceptible than others to the effects of aging. The main aim of this study is to investigate if the magnitude of functional hemispheric lateralization during episodic memory test was positively correlated with memory performance, proving the presence of a beneficial pattern of neural processing in high-performing older adults but not in low-performing participants. We have applied anodal transcranial Direct Current Stimulation (tDCS) or sham stimulation over left and right hemisphere in a group of young subjects and in high-performing and low-performing older participants during an experimental verbal episodic memory task. Remarkably, young individuals and high-performing older adults exhibited similar performances on episodic memory tasks and both groups showed symmetrical recruitment of left and right areas during memory retrieval. In contrast, low-performing older adults, who obtained lower scores on the memory tasks, demonstrated a greater engagement of the left hemisphere during verbal memory task. Furthermore, structural equation model was performed for analyzing the interrelations between the index of interhemispheric asymmetry and several neuropsychological domains. We found that the bilateral engagement of dorsolateral prefrontal cortex and parietal cortex regions had a direct correlation with memory and executive functions evaluated as latent constructs. These findings drew attention to brain maintenance hypothesis. The potential of neurostimulation in cognitive enhancement is particularly promising to prevent memory loss during aging. Copyright © 2015 Elsevier B.V. All rights reserved.
Dissociation between memory accuracy and memory confidence following bilateral parietal lesions.

PubMed

Simons, Jon S; Peers, Polly V; Mazuz, Yonatan S; Berryhill, Marian E; Olson, Ingrid R

2010-02-01

Numerous functional neuroimaging studies have observed lateral parietal lobe activation during memory tasks: a surprise to clinicians who have traditionally associated the parietal lobe with spatial attention rather than memory. Recent neuropsychological studies examining episodic recollection after parietal lobe lesions have reported differing results. Performance was preserved in unilateral lesion patients on source memory tasks involving recollecting the context in which stimuli were encountered, and impaired in patients with bilateral parietal lesions on tasks assessing free recall of autobiographical memories. Here, we investigated a number of possible accounts for these differing results. In 3 experiments, patients with bilateral parietal lesions performed as well as controls at source recollection, confirming the previous unilateral lesion results and arguing against an explanation for those results in terms of contralesional compensation. Reducing the behavioral relevance of mnemonic information critical to the source recollection task did not affect performance of the bilateral lesion patients, indicating that the previously observed reduced autobiographical free recall might not be due to impaired bottom-up attention. The bilateral patients did, however, exhibit reduced confidence in their source recollection abilities across the 3 experiments, consistent with a suggestion that parietal lobe lesions might lead to impaired subjective experience of rich episodic recollection.
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.
Auditory Memory Decay as Reflected by a New Mismatch Negativity Score Is Associated with Episodic Memory in Older Adults at Risk of Dementia

PubMed Central

Laptinskaya, Daria; Thurm, Franka; Küster, Olivia C.; Fissler, Patrick; Schlee, Winfried; Kolassa, Stephan; von Arnim, Christine A. F.; Kolassa, Iris-Tatjana

2018-01-01

The auditory mismatch negativity (MMN) is an event-related potential (ERP) peaking about 100–250 ms after the onset of a deviant tone in a sequence of identical (standard) tones. Depending on the interstimulus interval (ISI) between standard and deviant tones, the MMN is suitable to investigate the pre-attentive auditory discrimination ability (short ISIs, ≤ 2 s) as well as the pre-attentive auditory memory trace (long ISIs, >2 s). However, current results regarding the MMN as an index for mild cognitive impairment (MCI) and dementia are mixed, especially after short ISIs: while the majority of studies report positive associations between the MMN and cognition, others fail to find such relationships. To elucidate these so far inconsistent results, we investigated the validity of the MMN as an index for cognitive impairment exploring the associations between different MMN indices and cognitive performance, more specifically with episodic memory performance which is among the most affected cognitive domains in the course of Alzheimer’s dementia (AD), at baseline and at a 5-year-follow-up. We assessed the amplitude of the MMN for short ISI (stimulus onset asynchrony, SOA = 0.05 s) and for long ISI (3 s) in a neuropsychologically well-characterized cohort of older adults at risk of dementia (subjective memory impairment, amnestic and non-amnestic MCI; n = 57). Furthermore, we created a novel difference score (ΔMMN), defined as the difference between MMNs to short and to long ISI, as a measure to assess the decay of the auditory memory trace, higher values indicating less decay. ΔMMN and MMN amplitude after long ISI, but not the MMN amplitude after short ISI, was associated with episodic memory at baseline (β = 0.38, p = 0.003; β = −0.27, p = 0.047, respectively). ΔMMN, but not the MMN for long ISIs, was positively associated with episodic memory performance at the 5-year-follow-up (β = 0.57, p = 0.013). The results suggest that the MMN after long ISI might be suitable as an indicator for the decline in episodic memory and indicate ΔMMN as a potential biomarker for memory impairment in older adults at risk of dementia. PMID:29456500
Auditory Memory Decay as Reflected by a New Mismatch Negativity Score Is Associated with Episodic Memory in Older Adults at Risk of Dementia.

PubMed

Laptinskaya, Daria; Thurm, Franka; Küster, Olivia C; Fissler, Patrick; Schlee, Winfried; Kolassa, Stephan; von Arnim, Christine A F; Kolassa, Iris-Tatjana

2018-01-01

The auditory mismatch negativity (MMN) is an event-related potential (ERP) peaking about 100-250 ms after the onset of a deviant tone in a sequence of identical (standard) tones. Depending on the interstimulus interval (ISI) between standard and deviant tones, the MMN is suitable to investigate the pre-attentive auditory discrimination ability (short ISIs, ≤ 2 s) as well as the pre-attentive auditory memory trace (long ISIs, >2 s). However, current results regarding the MMN as an index for mild cognitive impairment (MCI) and dementia are mixed, especially after short ISIs: while the majority of studies report positive associations between the MMN and cognition, others fail to find such relationships. To elucidate these so far inconsistent results, we investigated the validity of the MMN as an index for cognitive impairment exploring the associations between different MMN indices and cognitive performance, more specifically with episodic memory performance which is among the most affected cognitive domains in the course of Alzheimer's dementia (AD), at baseline and at a 5-year-follow-up. We assessed the amplitude of the MMN for short ISI (stimulus onset asynchrony, SOA = 0.05 s) and for long ISI (3 s) in a neuropsychologically well-characterized cohort of older adults at risk of dementia (subjective memory impairment, amnestic and non-amnestic MCI; n = 57). Furthermore, we created a novel difference score (ΔMMN), defined as the difference between MMNs to short and to long ISI, as a measure to assess the decay of the auditory memory trace, higher values indicating less decay. ΔMMN and MMN amplitude after long ISI, but not the MMN amplitude after short ISI, was associated with episodic memory at baseline ( β = 0.38, p = 0.003; β = -0.27, p = 0.047, respectively). ΔMMN, but not the MMN for long ISIs, was positively associated with episodic memory performance at the 5-year-follow-up ( β = 0.57, p = 0.013). The results suggest that the MMN after long ISI might be suitable as an indicator for the decline in episodic memory and indicate ΔMMN as a potential biomarker for memory impairment in older adults at risk of dementia.
The functional neuroanatomy of autobiographical memory: A meta-analysis

PubMed Central

Svoboda, Eva; McKinnon, Margaret C.; Levine, Brian

2007-01-01

Autobiographical memory (AM) entails a complex set of operations, including episodic memory, self-reflection, emotion, visual imagery, attention, executive functions, and semantic processes. The heterogeneous nature of AM poses significant challenges in capturing its behavioral and neuroanatomical correlates. Investigators have recently turned their attention to the functional neuroanatomy of AM. We used the effect-location method of meta-analysis to analyze data from 24 functional imaging studies of AM. The results indicated a core neural network of left-lateralized regions, including the medial and ventrolateral prefrontal, medial and lateral temporal and retrosplenial/posterior cingulate cortices, the temporoparietal junction and the cerebellum. Secondary and tertiary regions, less frequently reported in imaging studies of AM, are also identified. We examined the neural correlates of putative component processes in AM, including, executive functions, self-reflection, episodic remembering and visuospatial processing. We also separately analyzed the effect of select variables on the AM network across individual studies, including memory age, qualitative factors (personal significance, level of detail and vividness), semantic and emotional content, and the effect of reference conditions. We found that memory age effects on medial temporal lobe structures may be modulated by qualitative aspects of memory. Studies using rest as a control task masked process-specific components of the AM neural network. Our findings support a neural distinction between episodic and semantic memory in AM. Finally, emotional events produced a shift in lateralization of the AM network with activation observed in emotion-centered regions and deactivation (or lack of activation) observed in regions associated with cognitive processes. PMID:16806314
Overlapping parietal activity in memory and perception: evidence for the attention to memory model.

PubMed

Cabeza, Roberto; Mazuz, Yonatan S; Stokes, Jared; Kragel, James E; Woldorff, Marty G; Ciaramelli, Elisa; Olson, Ingrid R; Moscovitch, Morris

2011-11-01

The specific role of different parietal regions to episodic retrieval is a topic of intense debate. According to the Attention to Memory (AtoM) model, dorsal parietal cortex (DPC) mediates top-down attention processes guided by retrieval goals, whereas ventral parietal cortex (VPC) mediates bottom-up attention processes captured by the retrieval output or the retrieval cue. This model also hypothesizes that the attentional functions of DPC and VPC are similar for memory and perception. To investigate this last hypothesis, we scanned participants with event-related fMRI whereas they performed memory and perception tasks, each comprising an orienting phase (top-down attention) and a detection phase (bottom-up attention). The study yielded two main findings. First, consistent with the AtoM model, orienting-related activity for memory and perception overlapped in DPC, whereas detection-related activity for memory and perception overlapped in VPC. The DPC overlap was greater in the left intraparietal sulcus, and the VPC overlap in the left TPJ. Around overlapping areas, there were differences in the spatial distribution of memory and perception activations, which were consistent with trends reported in the literature. Second, both DPC and VPC showed stronger connectivity with medial-temporal lobe during the memory task and with visual cortex during the perception task. These findings suggest that, during memory tasks, some parietal regions mediate similar attentional control processes to those involved in perception tasks (orienting in DPC vs. detection in VPC), although on different types of information (mnemonic vs. sensory).
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
The effects of gender on the retrieval of episodic and semantic components of autobiographical memory.

PubMed

Fuentes, Amanda; Desrocher, Mary

2013-01-01

Despite consistent evidence that women exhibit greater episodic memory specificity than men, little attention has been paid to gender differences in the production of episodic details during autobiographical recall under conditions of high and low retrieval support. Similarly the role of gender on the production of semantic details used to support autobiographical memory recollections of specific events has been largely unexplored. In the present study an undergraduate sample of 50 men and 50 women were assessed using the Autobiographical Interview (Levine, Svoboda, Hay, Winocur, & Moscovitch, 2002). Women recalled more episodic information compared to men in the high retrieval support condition, whereas no gender differences were found in the low retrieval support condition. In addition, women produced more repetitions compared to men in the high retrieval support condition. No gender differences were found in the production of semantic details. These results are interpreted in terms of gender differences in encoding and reminiscence practices. This research adds to the literature on gender differences in memory recall and suggests that gender is an important variable in explaining individual differences in AM recall.
Does Contralateral Delay Activity Reflect Working Memory Storage or the Current Focus of Spatial Attention within Visual Working Memory?

PubMed

Berggren, Nick; Eimer, Martin

2016-12-01

During the retention of visual information in working memory, event-related brain potentials show a sustained negativity over posterior visual regions contralateral to the side where memorized stimuli were presented. This contralateral delay activity (CDA) is generally believed to be a neural marker of working memory storage. In two experiments, we contrasted this storage account of the CDA with the alternative hypothesis that the CDA reflects the current focus of spatial attention on a subset of memorized items set up during the most recent encoding episode. We employed a sequential loading procedure where participants memorized four task-relevant items that were presented in two successive memory displays (M1 and M2). In both experiments, CDA components were initially elicited contralateral to task-relevant items in M1. Critically, the CDA switched polarity when M2 displays appeared on the opposite side. In line with the attentional activation account, these reversed CDA components exclusively reflected the number of items that were encoded from M2 displays, irrespective of how many M1 items were already held in working memory. On trials where M1 and M2 displays were presented on the same side and on trials where M2 displays appeared nonlaterally, CDA components elicited in the interval after M2 remained sensitive to a residual trace of M1 items, indicating that some activation of previously stored items was maintained across encoding episodes. These results challenge the hypothesis that CDA amplitudes directly reflect the total number of stored objects and suggest that the CDA is primarily sensitive to the activation of a subset of working memory representations within the current focus of spatial attention.
Cognitive training with casual video games: points to consider.

PubMed

Baniqued, Pauline L; Kranz, Michael B; Voss, Michelle W; Lee, Hyunkyu; Cosman, Joshua D; Severson, Joan; Kramer, Arthur F

2014-01-07

Brain training programs have proliferated in recent years, with claims that video games or computer-based tasks can broadly enhance cognitive function. However, benefits are commonly seen only in trained tasks. Assessing generalized improvement and practicality of laboratory exercises complicates interpretation and application of findings. In this study, we addressed these issues by using active control groups, training tasks that more closely resemble real-world demands and multiple tests to determine transfer of training. We examined whether casual video games can broadly improve cognition, and selected training games from a study of the relationship between game performance and cognitive abilities. A total of 209 young adults were randomized into a working memory-reasoning group, an adaptive working memory-reasoning group, an active control game group, and a no-contact control group. Before and after 15 h of training, participants completed tests of reasoning, working memory, attention, episodic memory, perceptual speed, and self-report measures of executive function, game experience, perceived improvement, knowledge of brain training research, and game play outside the laboratory. Participants improved on the training games, but transfer to untrained tasks was limited. No group showed gains in reasoning, working memory, episodic memory, or perceptual speed, but the working memory-reasoning groups improved in divided attention, with better performance in an attention-demanding game, a decreased attentional blink and smaller trail-making costs. Perceived improvements did not differ across training groups and those with low reasoning ability at baseline showed larger gains. Although there are important caveats, our study sheds light on the mixed effects in the training and transfer literature and offers a novel and potentially practical training approach. Still, more research is needed to determine the real-world benefits of computer programs such as casual games.
Autobiographical memory and structural brain changes in chronic phase TBI.

PubMed

Esopenko, Carrie; Levine, Brian

2017-04-01

Traumatic brain injury (TBI) is associated with a range of neuropsychological deficits, including attention, memory, and executive functioning attributable to diffuse axonal injury (DAI) with accompanying focal frontal and temporal damage. Although the memory deficit of TBI has been well characterized with laboratory tests, comparatively little research has examined retrograde autobiographical memory (AM) at the chronic phase of TBI, with no prior studies of unselected patients drawn directly from hospital admissions for trauma. Moreover, little is known about the effects of TBI on canonical episodic and non-episodic (e.g., semantic) AM processes. In the present study, we assessed the effects of chronic-phase TBI on AM in patients with focal and DAI spanning the range of TBI severity. Patients and socioeconomic- and age-matched controls were administered the Autobiographical Interview (AI) (Levine, Svoboda, Hay, Winocur, & Moscovitch, 2002) a widely used method for dissociating episodic and semantic elements of AM, along with tests of neuropsychological and functional outcome. Measures of episodic and non-episodic AM were compared with regional brain volumes derived from high-resolution structural magnetic resonance imaging (MRI). Severe TBI (but not mild or moderate TBI) was associated with reduced recall of episodic autobiographical details and increased recall of non-episodic details relative to healthy comparison participants. There were no significant associations between AM performance and neuropsychological or functional outcome measures. Within the full TBI sample, autobiographical episodic memory was associated with reduced volume distributed across temporal, parietal, and prefrontal regions considered to be part of the brain's AM network. These results suggest that TBI-related distributed volume loss affects episodic autobiographical recollection. Copyright © 2017 Elsevier Ltd. All rights reserved.
Resveratrol Supplementation Did Not Improve Cognition in Patients with Schizophrenia: Results from a Randomized Clinical Trial.

PubMed

Zortea, Karine; Franco, Viviane C; Guimarães, Paula; Belmonte-de-Abreu, Paulo S

2016-01-01

Schizophrenia (SZ) is associated with psychotic experiences and cognitive deficits. Therefore, cognitive function is one of the most critical determinants of quality of life in this pathology. Resveratrol has been related to neuroprotective action, but there are no studies evaluating resveratrol in SZ. The objective of this study was to determine the efficacy of resveratrol supplementation on cognition in individuals with SZ. This is a 1-month randomized, double-blind, and controlled trial (NCT 02062190), in which 19 men with diagnosis of SZ, aged 18-65 years, were assigned to a resveratrol supplementation group (200 mg) or placebo group (200 mg), with a 1-month follow-up. Applying a series of cognitive tests assessed neuropsychology performance (Hopkins Verbal Learning Test, Stroop Color and Word Test, and Weschler Adult Intelligence Scale) and Brief Psychiatric Rating Scale assessed psychopathology severity. There were no significant improvement in neuropsychology performance (episodic memory, working memory, attention and concentration capacity, inhibitory control, interference measures, selective attention, and mental flexibility) and psychopathology severity after 1 month of resveratrol supplementation ( P > 0.05). In conclusion, we have shown that 1 month of a resveratrol supplementation (200 mg/day) did not improve episodic memory, working memory, attention and concentration capacity, inhibitory control, interference measures, selective attention, and mental flexibility as compared with placebo in patients with SZ.
Moderators of noise-induced cognitive change in healthy adults.

PubMed

Wright, Bernice Al; Peters, Emmanuelle R; Ettinger, Ulrich; Kuipers, Elizabeth; Kumari, Veena

2016-01-01

Environmental noise causes cognitive impairment, particularly in executive function and episodic memory domains, in healthy populations. However, the possible moderating influences on this relationship are less clear. This study assessed 54 healthy participants (24 men) on a cognitive battery (measuring psychomotor speed, attention, executive function, working memory, and verbal learning and memory) under three (quiet, urban, and social) noise conditions. IQ, subjective noise sensitivity, sleep, personality, paranoia, depression, anxiety, stress, and schizotypy were assessed on a single occasion. We found significantly slower psychomotor speed (urban), reduced working memory and episodic memory (urban and social), and more cautious decision-making (executive function, urban) under noise conditions. There was no effect of sex. Variance in urban noise-induced changes in psychomotor speed, attention, Trail Making B-A (executive function), and immediate recall and social noise-induced changes in verbal fluency (executive function) and immediate recall were explained by a combination of baseline cognition and paranoia, noise sensitivity, sleep, or cognitive disorganization. Higher baseline cognition (but not IQ) predicted greater impairment under urban and social noise for most cognitive variables. Paranoia predicted psychomotor speed, attention, and executive function impairment. Subjective noise sensitivity predicted executive function and memory impairment. Poor sleep quality predicted less memory impairment. Finally, lower levels of cognitive disorganization predicted slower psychomotor speed and greater memory impairment. The identified moderators should be considered in studies aiming to reduce the detrimental effects of occupational and residential noise. These results highlight the importance of studying noise effects in clinical populations characterized by high levels of the paranoia, sleep disturbances, noise sensitivity, and cognitive disorganization.
Moderators of noise-induced cognitive change in healthy adults

PubMed Central

Wright, Bernice AL; Peters, Emmanuelle R; Ettinger, Ulrich; Kuipers, Elizabeth; Kumari, Veena

2016-01-01

Environmental noise causes cognitive impairment, particularly in executive function and episodic memory domains, in healthy populations. However, the possible moderating influences on this relationship are less clear. This study assessed 54 healthy participants (24 men) on a cognitive battery (measuring psychomotor speed, attention, executive function, working memory, and verbal learning and memory) under three (quiet, urban, and social) noise conditions. IQ, subjective noise sensitivity, sleep, personality, paranoia, depression, anxiety, stress, and schizotypy were assessed on a single occasion. We found significantly slower psychomotor speed (urban), reduced working memory and episodic memory (urban and social), and more cautious decision-making (executive function, urban) under noise conditions. There was no effect of sex. Variance in urban noise-induced changes in psychomotor speed, attention, Trail Making B-A (executive function), and immediate recall and social noise-induced changes in verbal fluency (executive function) and immediate recall were explained by a combination of baseline cognition and paranoia, noise sensitivity, sleep, or cognitive disorganization. Higher baseline cognition (but not IQ) predicted greater impairment under urban and social noise for most cognitive variables. Paranoia predicted psychomotor speed, attention, and executive function impairment. Subjective noise sensitivity predicted executive function and memory impairment. Poor sleep quality predicted less memory impairment. Finally, lower levels of cognitive disorganization predicted slower psychomotor speed and greater memory impairment. The identified moderators should be considered in studies aiming to reduce the detrimental effects of occupational and residential noise. These results highlight the importance of studying noise effects in clinical populations characterized by high levels of the paranoia, sleep disturbances, noise sensitivity, and cognitive disorganization. PMID:27157685

Age-related changes in neural oscillations supporting context memory retrieval

PubMed Central

Strunk, Jonathan; James, Taylor; Arndt, Jason; Duarte, Audrey

2018-01-01

Recent evidence suggests that directing attention toward single item-context associations during encoding improves young and older adults’ context memory performance and reduces demands on executive functions during retrieval. In everyday situations, there are many event features competing for our attention, and our ability to successfully recover those details may depend on our ability to ignore others. Failures of selective attention may contribute to older adults’ context memory impairments. In the current electroencephalogram (EEG) study, we assessed the effects of age on processes supporting successful context memory retrieval of selectively attended features as indexed by neural oscillations. During encoding, young and older adults were directed to attend to a picture of an object and its relationship to one of two concurrently presented contextual details: a color or scene. At retrieval, we tested their memory for the object, its attended and unattended context features, and their confidence for both the attended and unattended features. Both groups showed greater memory for attended than unattended contextual features. However, older adults showed evidence of hyper-binding between attended and unattended context features while the young adults did not. EEG results in the theta band suggest that young and older adults recollect similar amounts of information but brain-behavior correlations suggest that this information was supportive of contextual memory performance, particularly for young adults. By contrast, sustained beta desynchronization, indicative of sensory reactivation and episodic reconstruction, was correlated with contextual memory performance for older adults only. We conclude that older adults’ inhibition deficits during encoding reduced the selectivity of their contextual memories, which led to reliance on executive functions like episodic reconstruction to support successful memory retrieval. PMID:28237686
Age-related changes in neural oscillations supporting context memory retrieval.

PubMed

Strunk, Jonathan; James, Taylor; Arndt, Jason; Duarte, Audrey

2017-06-01

Recent evidence suggests that directing attention toward single item-context associations during encoding improves young and older adults' context memory performance and reduces demands on executive functions during retrieval. In everyday situations, there are many event features competing for our attention, and our ability to successfully recover those details may depend on our ability to ignore others. Failures of selective attention may contribute to older adults' context memory impairments. In the current electroencephalogram (EEG) study, we assessed the effects of age on processes supporting successful context memory retrieval of selectively attended features as indexed by neural oscillations. During encoding, young and older adults were directed to attend to a picture of an object and its relationship to one of two concurrently presented contextual details: a color or scene. At retrieval, we tested their memory for the object, its attended and unattended context features, and their confidence for both the attended and unattended features. Both groups showed greater memory for attended than unattended contextual features. However, older adults showed evidence of hyper-binding between attended and unattended context features while the young adults did not. EEG results in the theta band suggest that young and older adults recollect similar amounts of information but brain-behavior correlations suggest that this information was supportive of contextual memory performance, particularly for young adults. By contrast, sustained beta desynchronization, indicative of sensory reactivation and episodic reconstruction, was correlated with contextual memory performance for older adults only. We conclude that older adults' inhibition deficits during encoding reduced the selectivity of their contextual memories, which led to reliance on executive functions like episodic reconstruction to support successful memory retrieval. Copyright © 2017 Elsevier Ltd. All rights reserved.
The G72/G30 gene complex and cognitive abnormalities in schizophrenia.

PubMed

Goldberg, Terry E; Straub, Richard E; Callicott, Joseph H; Hariri, Ahmad; Mattay, Venkata S; Bigelow, Llewellyn; Coppola, Richard; Egan, Michael F; Weinberger, Daniel R

2006-09-01

A recently discovered gene complex, G72/G30 (hereafter G72, but now termed DAOA), was found to be associated with schizophrenia and with bipolar disorder, possibly because of an indirect effect on NMDA neurotransmission. In principle, if G72 increases risk for psychosis by this mechanism, it might impact with greater penetrance those cortically based cognitive and neurophysiological functions associated with NMDA signaling. We performed two independent family-based association studies (one sample contained more than 200 families and the other more than 65) of multiple SNPs in the G72 region and of multiple SNPs in the gene for D-amino acid oxidase (DAAO), which may be modulated by G72. We examined the relationship between select cognitive measures in attention, working memory, and episodic memory and a restricted set of G72 SNPs in over 600 normal controls, schizophrenic patients, and their nonpsychotic siblings using mixed model ANOVAs. We also determined genotype effects on neurophysiology measures in normal controls using the fMRI BOLD response obtained during activation procedures involving either episodic memory or working memory. There were no significant single G72 SNP associations and clinical diagnosis in either sample, though one approached significance (p=0.06). Diagnosis by genotype interaction effects for G72 SNP 10 were significant for cognitive variables assessing working memory and attention (p=0.05), and at the trend level for episodic memory, such that in the schizophrenia group an exaggerated allele load effect in the predicted directions was observed. In the fMRI paradigms, a strong effect of G72 SNP 10 genotype was observed on BOLD activation in the hippocampus during the episodic memory paradigm. Tests of association with DAAO were consistently nonsignificant. We present evidence that SNP variations in the G72 gene region increase risk of cognitive impairment in schizophrenia. SNP variations were not strongly associated with clinical diagnosis in family-based analyses.
Sex-specific cognitive abnormalities in early-onset psychosis.

PubMed

Ruiz-Veguilla, Miguel; Moreno-Granados, Josefa; Salcedo-Marin, Maria D; Barrigon, Maria L; Blanco-Morales, Maria J; Igunza, Evelio; Cañabate, Anselmo; Garcia, Maria D; Guijarro, Teresa; Diaz-Atienza, Francisco; Ferrin, Maite

2017-01-01

Brain maturation differs depending on the area of the brain and sex. Girls show an earlier peak in maturation of the prefrontal cortex. Although differences between adult females and males with schizophrenia have been widely studied, there has been less research in girls and boys with psychosis. The purpose of this study was to examine differences in verbal and visual memory, verbal working memory, auditory attention, processing speed, and cognitive flexibility between boys and girls. We compared a group of 80 boys and girls with first-episode psychosis to a group of controls. We found interactions between group and sex in verbal working memory (p = 0.04) and auditory attention (p = 0.01). The female controls showed better working memory (p = 0.01) and auditory attention (p = 0.001) than males. However, we did not find any sex differences in working memory (p = 0.91) or auditory attention (p = 0.93) in the psychosis group. These results are consistent with the presence of sex-modulated cognitive profiles at first presentation of early-onset psychosis.
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.
Nondirective meditation activates default mode network and areas associated with memory retrieval and emotional processing.

PubMed

Xu, Jian; Vik, Alexandra; Groote, Inge R; Lagopoulos, Jim; Holen, Are; Ellingsen, Oyvind; Håberg, Asta K; Davanger, Svend

2014-01-01

Nondirective meditation techniques are practiced with a relaxed focus of attention that permits spontaneously occurring thoughts, images, sensations, memories, and emotions to emerge and pass freely, without any expectation that mind wandering should abate. These techniques are thought to facilitate mental processing of emotional experiences, thereby contributing to wellness and stress management. The present study assessed brain activity by functional magnetic resonance imaging (fMRI) in 14 experienced practitioners of Acem meditation in two experimental conditions. In the first, nondirective meditation was compared to rest. Significantly increased activity was detected in areas associated with attention, mind wandering, retrieval of episodic memories, and emotional processing. In the second condition, participants carried out concentrative practicing of the same meditation technique, actively trying to avoid mind wandering. The contrast nondirective meditation > concentrative practicing was characterized by higher activity in the right medial temporal lobe (parahippocampal gyrus and amygdala). In conclusion, the present results support the notion that nondirective meditation, which permits mind wandering, involves more extensive activation of brain areas associated with episodic memories and emotional processing, than during concentrative practicing or regular rest.
Nondirective meditation activates default mode network and areas associated with memory retrieval and emotional processing

PubMed Central

Xu, Jian; Vik, Alexandra; Groote, Inge R.; Lagopoulos, Jim; Holen, Are; Ellingsen, Øyvind; Håberg, Asta K.; Davanger, Svend

2014-01-01

Nondirective meditation techniques are practiced with a relaxed focus of attention that permits spontaneously occurring thoughts, images, sensations, memories, and emotions to emerge and pass freely, without any expectation that mind wandering should abate. These techniques are thought to facilitate mental processing of emotional experiences, thereby contributing to wellness and stress management. The present study assessed brain activity by functional magnetic resonance imaging (fMRI) in 14 experienced practitioners of Acem meditation in two experimental conditions. In the first, nondirective meditation was compared to rest. Significantly increased activity was detected in areas associated with attention, mind wandering, retrieval of episodic memories, and emotional processing. In the second condition, participants carried out concentrative practicing of the same meditation technique, actively trying to avoid mind wandering. The contrast nondirective meditation > concentrative practicing was characterized by higher activity in the right medial temporal lobe (parahippocampal gyrus and amygdala). In conclusion, the present results support the notion that nondirective meditation, which permits mind wandering, involves more extensive activation of brain areas associated with episodic memories and emotional processing, than during concentrative practicing or regular rest. PMID:24616684
Divided attention selectively impairs memory for self-relevant information.

PubMed

Turk, David J; Brady-van den Bos, Mirjam; Collard, Philip; Gillespie-Smith, Karri; Conway, Martin A; Cunningham, Sheila J

2013-05-01

Information that is relevant to oneself tends to be remembered more than information that relates to other people, but the role of attention in eliciting this "self-reference effect" is unclear. In the present study, we assessed the importance of attention in self-referential encoding using an ownership paradigm, which required participants to encode items under conditions of imagined ownership by themselves or by another person. Previous work has established that this paradigm elicits a robust self-reference effect, with more "self-owned" items being remembered than "other-owned" items. Access to attentional resources was manipulated using divided-attention tasks at encoding. A significant self-reference effect emerged under full-attention conditions and was related to an increase in episodic recollection for self-owned items, but dividing attention eliminated this memory advantage. These findings are discussed in relation to the nature of self-referential cognition and the importance of attentional resources at encoding in the manifestation of the self-reference effect in memory.
Confabulation in healthy aging is related to poor encoding and retrieval of over-learned information.

PubMed

Attali, Eve; Dalla Barba, Gianfranco

2013-01-01

Normal aging is characterized by deficits that cross multiple cognitive domains including episodic memory and attention. Compared to young adults (YA), older adults (OA) not only show reduction in true memories, but also an increase in false memories. In this study we aim to elucidate how the production of confabulation is influenced by encoding and retrieval processes. We hypothesized that in OA, compared to YA, over-learned information interferes with the recall of specific, unique past episodes and this interference should be more prominent when a concurrent task perturbs the encoding of the episodes to be recalled. We tested this hypothesis using an experimental paradigm in which a group of OA and a group of YA had to recall three different types of story: a previously unknown story, a well-known fairy tale (Snow White), and a modified well-known fairy tale (Little Red Riding Hood is not eaten by the wolf), in three different experimental conditions: (1) free encoding and free retrieval; (2) Divided attention (DA) at encoding and free retrieval; and (3) free encoding and DA at retrieval. Results showed that OA produced significantly more confabulations than YA, particularly, in the recall of the modified fairy tale. Moreover, DA at encoding markedly increased the number of confabulations, whereas DA at retrieval had no effect on confabulation. Our findings reveal the implications of two phenomena in the production of confabulation in normal aging: the effect of poor encoding and the interference of strongly represented, over-learned information in episodic memory recall.
Lower cognitive performance among long-term type 1 diabetes survivors: A case-control study.

PubMed

Awad, Anna; Lundqvist, Robert; Rolandsson, Olov; Sundström, Anna; Eliasson, Mats

2017-08-01

Patients with type 1 diabetes (T1D) have an increased risk of cognitive dysfunction. The cognitive decrement is believed to depend on macro- and microvascular complications and long disease duration. Some patients do not develop these complications, but still report cognitive symptoms. We examined if long-standing T1D without complications is associated with lower cognitive performance. A group of patients (n=43) with long-standing T1D (>30years) without micro- or macro vascular complications was compared with a non-diabetic control group (n=86) on six cognitive tests which probed episodic memory, semantic memory, episodic short-term memory, visual attention and psychomotor speed. Each patient was matched with two controls regarding age, gender and education. A linear mixed effect model was used to analyze the data. The mean age was 57years and mean duration was 41years. Patients with diabetes had lower diastolic blood pressure but BMI, waist circumference, systolic blood pressure and smoking did not differ between groups. Patients had lower results than non-diabetic controls in episodic short-term memory (p<0.001) and also lower values on a test that mirrors visual attention and psychomotor speed (p=0.019). Long-standing T1D was associated with lower cognitive performance, regardless of other diabetes-related complications. Copyright © 2017 Elsevier Inc. All rights reserved.
Retrieval Search and Strength Evoke Dissociable Brain Activity during Episodic Memory Recall

PubMed Central

Reas, Emilie T.; Brewer, James B.

2014-01-01

Neuroimaging studies of episodic memory retrieval have revealed activations in the human frontal, parietal, and medial-temporal lobes that are associated with memory strength. However, it remains unclear whether these brain responses are veritable signals of memory strength or are instead regulated by concomitant subcomponents of retrieval such as retrieval effort or mental search. This study used event-related fMRI during cued recall of previously memorized word-pair associates to dissociate brain responses modulated by memory search from those modulated by the strength of a recalled memory. Search-related deactivations, dissociated from activity due to memory strength, were observed in regions of the default network, whereas distinctly strength-dependent activations were present in superior and inferior parietal and dorsolateral PFC. Both search and strength regulated activity in dorsal anterior cingulate and anterior insula. These findings suggest that, although highly correlated and partially subserved by overlapping cognitive control mechanisms, search and memory strength engage dissociable regions of frontoparietal attention and default networks. PMID:23190328
A comparison of the effects of a secondary task and lorazepam on cognitive performance.

PubMed

File, S E

1992-01-01

In order to test whether the lorazepam-induced impairments in a variety of cognitive tasks were similar to those of divided attention, the effects of lorazepam (2.5 mg) in healthy volunteers were compared with those requiring subjects to perform an additional task (detecting silences superimposed onto classical music). Neither treatment impaired implicit memory or judgements of frequency. Both treatments impaired performance in tests of speed, lorazepam having the greatest effect on number cancellation and the additional task having the greatest effect on simple reaction time. Both treatments impaired performance in a coding task, in a test of explicit episodic memory and in judgements of recency (indicating impaired coding of contextual information). Lorazepam significantly reduced performance in a word completion task, but this was unimpaired in the group performing the additional task. In general, the pattern of results suggests that there are similarities between the effects of divided attention and lorazepam treatment, and that lorazepam-induced cognitive impairments are not restricted to explicit tests of episodic memory.
The effects of acute tryptophan depletion and serotonin transporter polymorphism on emotional processing in memory and attention.

PubMed

Roiser, Jonathan P; Müller, Ulrich; Clark, Luke; Sahakian, Barbara J

2007-08-01

Polymorphism at the serotonin transporter linked polymorphic region (5-HTTLPR) has been associated with neuroticism, increased risk for affective disorders and greater vulnerability to mood change following serotonin (5-HT) depletion. The aim of the present study was to investigate whether the cognitive effects of 5-HT depletion were differentially affected by genotype at the 5-HTTLPR polymorphism, using neuropsychological measures of memory and attention. We utilized the acute tryptophan depletion (ATD) technique to temporarily reduce 5-HT synthesis in two groups of healthy volunteers pre-selected on the basis of 5-HTTLPR genotype, 15 of the ll genotype and 15 of the ss genotype, in a double-blind, placebo-controlled crossover design. As expected, ATD resulted in a robust reduction in plasma tryptophan concentration in both genotype groups. However, the genotype groups differed in terms of the effect of ATD on cognitive performance. The ss genotype group showed impaired verbal recall following depletion, while episodic memory was unimpaired by ATD in the ll genotype group. Averaging across depletion condition, the ss genotype group outperformed the ll genotype group on tests of episodic memory and attention. Neither group was significantly affected by ATD on measures of emotional state. These data confirm previous reports that ss individuals are particularly vulnerable to 5-HT depletion, but extend these findings to the cognitive domain. The unexpected finding that ss volunteers showed improved memory and attention relative to ll volunteers suggests a possible evolutionary advantage to possession of the s allele, which may offset the disadvantage of vulnerability to depression following stressful life events.
Does multitasking mediate the relationships between episodic memory, attention, executive functions and apathetic manifestations in traumatic brain injury?

PubMed

Arnould, Annabelle; Rochat, Lucien; Dromer, Emilie; Azouvi, Philippe; Van der Linden, Martial

2018-03-01

Apathy is frequently described in patients with traumatic brain injury (TBI); its negative consequences particularly affect functional independence. Among apathetic manifestations, lack of initiative and lack of interest have mainly been associated with cognitive impairments. However, few studies have been conducted to precisely identify the underlying cognitive processes. Our aims were (1) to determine the best predictor of apathy from among several cognitive processes, including episodic memory and attention/executive mechanisms and multitasking, and (2) to examine to what extent multitasking could mediate the relationships between specific cognitive processes and lack of initiative/interest. Seventy participants (34 patients with TBI matched with 36 control participants) were given a questionnaire to assess anxio-depressive symptoms, four tasks to assess specific cognitive processes, and one task to assess real-life multitasking. Participants' relatives completed an apathy questionnaire. Multitasking, as assessed by the number of goals not achieved, was the only significant predictor of apathetic manifestations. In addition, the mediation analyses revealed that multitasking performance mediated the relationships between verbal episodic memory and lack of initiative/interest, whereas executive and attentional functions were only indirectly related to lack of initiative/interest due to their significant impacts on multitasking. These results shed new light on the aetiology of apathetic manifestations in patients with TBI, indicating how specific cognitive deficits are expressed in real-life multitasking, and consequently, how they may lead to the development and/or maintenance of apathetic manifestations. © 2016 The British Psychological Society.
Episodic memory, concentrated attention and processing speed in aging: A comparative study of Brazilian age groups.

PubMed

Fonseca, Rochele Paz; Zimmermann, Nicolle; Scherer, Lilian Cristine; Parente, Maria Alice de Mattos Pimenta; Ska, Bernadette

2010-01-01

Neuropsychological studies on the processing of some specific cognitive functions throughout aging are essential for the understanding of human cognitive development from ages 19 to 89. This study aimed to verify the occurrence of differences in the processing of episodic memory, concentrated attention and speed of attentional processing among four age groups of adults. A total of 136 neurologically healthy adults, aged 19-89, with 9 or more years of schooling, took part in the study. Participants were divided according to four age groups: young, middle-aged, elderly and oldest old adults. Subtests of the Brief Neuropsychological Evaluation Instrument (NEUPSILIN) were applied for the cognitive assessment. Mean score of corrected answers and of response times were compared between groups by means of a one-way ANOVA test with post-hoc Scheffe procedures and ANCOVA including the co-variables of years of schooling and socio-economical scores. In general, differences in performance were observed from 60 years old on. Only the episodic memory task of delayed recall reflected differences from the age of around 40 onwards and processing speed from around the age of 70 onwards. Thus, differences were found between the age groups regarding their cognitive performance, particularly between young adults and elderly adults, and young adults and oldest old adults. Our research indicates that the middle-aged group should be better analyzed and that comparative cross-sectional studies including only extreme groups such as young and elderly adults are not sufficient.
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
Do subjective measures of attention and memory predict actual performance? Metacognition in older couples.

PubMed

Volz-Sidiropoulou, Eftychia; Gauggel, Siegfried

2012-06-01

Older individuals who recognize their cognitive difficulties are more likely to adjust their everyday life to their actual cognitive functioning, particularly when they are able to estimate their abilities accurately. We assessed self- and spouse-ratings of memory and attention difficulties in everyday life of healthy, older individuals and compared them with the respective test performance. Eighty-four older individuals (women's age, M = 67.4 years, SD = 5.2; men's age, M = 68.5 years, SD = 4.9) completed both the self and the spouse versions of the Attention Deficit Questionnaire and the Everyday Memory Questionnaire and completed two neuropsychological tests. Using the residual score approach, subjective metacognitive measures of memory and attention were created and compared with actual test performance. Significant associations between subjective and objective scores were found only for men and only for episodic memory measures. Men who underreported memory difficulties performed more poorly; men who overreported memory difficulties performed better. Men's recognition performance was best predicted by subjective measures (R² = .25), followed by delayed recall (R² = .14) and forgetting rate (R² = .13). The results indicate gender-specific differences in metacognitive accuracy and predictive validity of subjective ratings. PsycINFO Database Record (c) 2012 APA, all rights reserved
The relationship between level of processing and hippocampal-cortical functional connectivity during episodic memory formation in humans.

PubMed

Schott, Björn H; Wüstenberg, Torsten; Wimber, Maria; Fenker, Daniela B; Zierhut, Kathrin C; Seidenbecher, Constanze I; Heinze, Hans-Jochen; Walter, Henrik; Düzel, Emrah; Richardson-Klavehn, Alan

2013-02-01

New episodic memory traces represent a record of the ongoing neocortical processing engaged during memory formation (encoding). Thus, during encoding, deep (semantic) processing typically establishes more distinctive and retrievable memory traces than does shallow (perceptual) processing, as assessed by later episodic memory tests. By contrast, the hippocampus appears to play a processing-independent role in encoding, because hippocampal lesions impair encoding regardless of level of processing. Here, we clarified the neural relationship between processing and encoding by examining hippocampal-cortical connectivity during deep and shallow encoding. Participants studied words during functional magnetic resonance imaging and freely recalled these words after distraction. Deep study processing led to better recall than shallow study processing. For both levels of processing, successful encoding elicited activations of bilateral hippocampus and left prefrontal cortex, and increased functional connectivity between left hippocampus and bilateral medial prefrontal, cingulate and extrastriate cortices. Successful encoding during deep processing was additionally associated with increased functional connectivity between left hippocampus and bilateral ventrolateral prefrontal cortex and right temporoparietal junction. In the shallow encoding condition, on the other hand, pronounced functional connectivity increases were observed between the right hippocampus and the frontoparietal attention network activated during shallow study processing. Our results further specify how the hippocampus coordinates recording of ongoing neocortical activity into long-term memory, and begin to provide a neural explanation for the typical advantage of deep over shallow study processing for later episodic memory. Copyright © 2011 Wiley Periodicals, Inc.
What is the contribution of different cognitive biases and stressful childhood events to the presence and number of previous depressive episodes?

PubMed

Vrijsen, Janna N; Becker, Eni S; Arias-Vásquez, Alejandro; van Dijk, Maarten K; Speckens, Anne; Oostrom, Iris van

2014-07-30

Negative cognitive biases as well as stressful childhood events are well-known risk factors for depression. Few studies have compared the association of different types of biases and events with depression. The current study examined whether different cognitive biases and stressful childhood events variables were associated with depression and recurrence. Three types of childhood events were assessed in 83 never-depressed and 337 formerly depressed individuals: trauma within the family, trauma outside the family, and adverse events. Furthermore, after a sad mood induction procedure, participants executed a Dot Probe task (selective attentional bias), an Emotional Stroop task (attentional interference bias) and an incidental learning task (memory bias). The association of these measures with case status and recurrence status (one or multiple past episodes) was examined. Negative memory bias and traumatic childhood events within the family were associated with case status, whereas none of the bias measures or childhood events variables were associated with recurrence status. The results indicate that memory bias as well as the experience of aggression and/or abuse within the family during childhood are independently associated with depression. Biases and stressful childhood events did not offer differentiation between individuals with one or multiple past episodes. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

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.
The chemotherapeutic agent paclitaxel selectively impairs reversal learning while sparing prior learning, new learning and episodic memory.

PubMed

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

2017-10-01

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

PubMed

Lega, Bradley; Germi, James; Rugg, Michael

2017-08-01

Existing data from noninvasive studies have led researchers to posit that the posterior cingulate cortex (PCC) supports mnemonic processes: It exhibits degeneration in memory disorders, and fMRI investigations have demonstrated memory-related activation principally during the retrieval of memory items. Despite these data, the role of the PCC in episodic memory has received only limited treatment using the spatial and temporal precision of intracranial EEG, with previous analyses focused on item retrieval. Using data gathered from 21 human participants who underwent stereo-EEG for seizure localization, we characterized oscillatory patterns in the PCC during the encoding and retrieval of episodic memories. We identified a subsequent memory effect during item encoding characterized by increased gamma band oscillatory power and a low-frequency power desynchronization. Fourteen participants had stereotactic electrodes located simultaneously in the hippocampus and PCC, and with these unique data, we describe connectivity changes between these structures that predict successful item encoding and that precede item retrieval. Oscillatory power during retrieval matched the pattern we observed during encoding, with low-frequency (below 15 Hz) desynchronization and a gamma band (especially high gamma, 70-180 Hz) power increase. Encoding is characterized by synchrony between the hippocampus and PCC, centered at 3 Hz, consistent with other observations of properties of this oscillation akin to those for rodent theta activity. We discuss our findings in light of existing theories of episodic memory processing, including the information via desynchronization hypothesis and retrieved context theory, and examine how our data fit with existing theories for the functional role of the PCC. These include a postulated role for the PCC in modulating internally directed attention and for representing or integrating contextual information for memory items.
Neural Mechanisms of Episodic Retrieval Support Divergent Creative Thinking.

PubMed

Madore, Kevin P; Thakral, Preston P; Beaty, Roger E; Addis, Donna Rose; Schacter, Daniel L

2017-11-17

Prior research has indicated that brain regions and networks that support semantic memory, top-down and bottom-up attention, and cognitive control are all involved in divergent creative thinking. Kernels of evidence suggest that neural processes supporting episodic memory-the retrieval of particular elements of prior experiences-may also be involved in divergent thinking, but such processes have typically been characterized as not very relevant for, or even a hindrance to, creative output. In the present study, we combine functional magnetic resonance imaging with an experimental manipulation to test formally, for the first time, episodic memory's involvement in divergent thinking. Following a manipulation that facilitates detailed episodic retrieval, we observed greater neural activity in the hippocampus and stronger connectivity between a core brain network linked to episodic processing and a frontoparietal brain network linked to cognitive control during divergent thinking relative to an object association control task that requires little divergent thinking. Stronger coupling following the retrieval manipulation extended to a subsequent resting-state scan. Neural effects of the episodic manipulation were consistent with behavioral effects of enhanced idea production on divergent thinking but not object association. The results indicate that conceptual frameworks should accommodate the idea that episodic retrieval can function as a component process of creative idea generation, and highlight how the brain flexibly utilizes the retrieval of episodic details for tasks beyond simple remembering. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
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.
Binding in visual working memory: the role of the episodic buffer.

PubMed

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

2011-05-01

The episodic buffer component of working memory is assumed to play a central role in the binding of features into objects, a process that was initially assumed to depend upon executive resources. Here, we review a program of work in which we specifically tested this assumption by studying the effects of a range of attentionally demanding concurrent tasks on the capacity to encode and retain both individual features and bound objects. We found no differential effect of concurrent load, even when the process of binding was made more demanding by separating the shape and color features spatially, temporally or across visual and auditory modalities. Bound features were however more readily disrupted by subsequent stimuli, a process we studied using a suffix paradigm. This suggested a need to assume a feature-based attentional filter followed by an object based storage process. Our results are interpreted within a modified version of the multicomponent working memory model. We also discuss work examining the role of the hippocampus in visual feature binding. Copyright © 2011 Elsevier Ltd. All rights reserved.
Impaired MMN/P3a complex in first-episode psychosis: cognitive and psychosocial associations.

PubMed

Hermens, Daniel F; Ward, Philip B; Hodge, M Antoinette Redoblado; Kaur, Manreena; Naismith, Sharon L; Hickie, Ian B

2010-08-16

Mismatch negativity (MMN) is a neurophysiological indicator of the brain's ability to extract relevant information from an irrelevant background. The P3a orienting response often accompanies MMN in deviance detection paradigms. Both MMN and P3a have been described as reliable biomarkers of schizophrenia. MMN/P3a impairments are associated with deficits in verbal memory and attentional switching, reflecting dysfunctions in the temporal and frontal systems, respectively. It remains unresolved whether MMN/P3a are robust biomarkers of psychosis in first-episode patients. Thirty-four young people (18 to 30years) were assessed in this study; 17 first-episode psychosis (FEP) patients were compared to 17 healthy controls. To elicit MMN/P3a, a two-tone passive auditory oddball paradigm with 8% duration deviants was used; event-related potentials were recorded at frontal, central and temporal (mastoid) sites. Neuropsychological assessments included processing speed, attentional switching, simple attention, and verbal learning and memory. Social functioning and quality of life measures were also obtained. The FEP group showed significantly reduced MMN amplitudes compared to controls. The FEP group also showed significantly reduced P3a amplitudes at frontal and central sites compared with controls. As expected, the FEP group also showed significant deficits in attention and verbal learning/memory. Correlational analyses found strong associations between fronto-central MMN/P3a peak amplitude and cognitive/psychosocial functioning. This study provides evidence of early neurobiological markers in young people with FEP. These findings suggest that MMN/P3a impairments are present at early stages of psychosis and that fundamental pre-attentive/deviance detection deficits may mark the beginning of progressive underlying changes with illness onset. Such deficits in FEP appear to have important links with higher-order cognitive and psychosocial functioning. Copyright (c) 2010 Elsevier Inc. All rights reserved.
Genetic Complexity of Episodic Memory: A Twin Approach to Studies of Aging

PubMed Central

Kremen, William S.; Spoon, Kelly M.; Jacobson, Kristen C.; Vasilopoulos, Terrie; McCaffery, Jeanne M.; Panizzon, Matthew S.; Franz, Carol E.; Vuoksimaa, Eero; Xian, Hong; Rana, Brinda K.; Toomey, Rosemary; McKenzie, Ruth; Lyons, Michael J.

2016-01-01

Episodic memory change is a central issue in cognitive aging, and understanding that process will require elucidation of its genetic underpinnings. A key limiting factor in genetically informed research on memory has been lack of attention to genetic and phenotypic complexity, as if “memory is memory” and all well-validated assessments are essentially equivalent. Here we applied multivariate twin models to data from late-middle-aged participants in the Vietnam Era Twin Study of Aging to examine the genetic architecture of 6 measures from 3 standard neuropsychological tests: the California Verbal Learning Test-2, and Wechsler Memory Scale-III Logical Memory (LM) and Visual Reproductions (VR). An advantage of the twin method is that it can estimate the extent to which latent genetic influences are shared or independent across different measures before knowing which specific genes are involved. The best-fitting model was a higher order common pathways model with a heritable higher order general episodic memory factor and three test-specific subfactors. More importantly, substantial genetic variance was accounted for by genetic influences that were specific to the latent LM and VR subfactors (28% and 30%, respectively) and independent of the general factor. Such unique genetic influences could partially account for replication failures. Moreover, if different genes influence different memory phenotypes, they could well have different age-related trajectories. This approach represents an important step toward providing critical information for all types of genetically informative studies of aging and memory. PMID:24956007
On remembering and forgetting our autobiographical pasts: retrograde amnesia and Andrew Mayes's contribution to neuropsychological method.

PubMed

Kopelman, M D; Bright, P

2012-11-01

Andrew Mayes's contribution to the neuropsychology of memory has consisted in steadily teasing out the nature of the memory deficit in the amnesic syndrome. This has been done with careful attention to matters of method at all stages. This particularly applies to his investigations of forgetting rates in amnesia and to his studies of retrograde amnesia. Following a brief outline of his work, the main current theories of retrograde amnesia are considered: consolidation theory, episodic-to-semantic shift theory, and multiple trace theory. Findings across the main studies in Alzheimer dementia are reviewed to illustrate what appears to be consistently found, and what is much more inconsistent. A number of problems and issues in current theories are then highlighted--including the nature of the temporal gradient, correlations with the extent of temporal lobe damage, what we would expect 'normal' remote memory curves to look like, how they would appear in focal retrograde amnesia, and whether we can pinpoint retrograde amnesia to hippocampal/medial temporal damage on the basis of existing studies. A recent study of retrograde amnesia is re-analysed to demonstrate temporal gradients on recollected episodic memories in hippocampal/medial temporal patients. It is concluded that there are two requirements for better understanding of the nature of retrograde amnesia: (i) a tighter, Mayesian attention to method in terms of both the neuropsychology and neuroimaging in investigations of retrograde amnesia; and (ii) acknowledging that there may be multiple factors underlying a temporal gradient, and that episodic and semantic memory show important interdependencies at both encoding and retrieval. Such factors may be critical to understanding what is remembered and what is forgotten from our autobiographical pasts. Copyright © 2012 Elsevier Ltd. All rights reserved.
What–where–when memory and encoding strategies in healthy aging

PubMed Central

2016-01-01

Older adults exhibit disproportionate impairments in memory for item-associations. These impairments may stem from an inability to self-initiate deep encoding strategies. The present study investigates this using the “treasure-hunt task”; a what–where–when style episodic memory test that requires individuals to “hide” items around complex scenes. This task separately assesses memory for item, location, and temporal order, as well as bound what–where–when information. The results suggest that older adults are able to ameliorate integration memory deficits by using self-initiated encoding strategies when these are externally located and therefore place reduced demands on working memory and attentional resources. PMID:26884230
Cognitive functions in first-episode depression and recurrent depressive disorder.

PubMed

Talarowska, Monika; Zajączkowska, Marlena; Gałecki, Piotr

2015-03-01

Cognitive deficits in the course of depressive disorders affect mainly memory, attention and the frontal functions. They are associated with both an earlier onset of symptoms and prolonged episodes. The main aim of the study was to verify the hypothesis of differences in the effectiveness of cognitive processes between patients with a first episode of depression (ED-I) and recurrent depressive disorders (rDD). The study comprised 210 subjects: patients with ED-I (n=60) and patients with rDD (n=150). The assessment of cognitive functions was based on performance of the Trail Making Test, the Stroop Test, the Verbal Fluency Test, the California Verbal Learning Test (CVLT) and the digit span from WAIS-R. There were no statistically significant differences between the analysed groups in the severity of depressive symptoms. The negative impact of depressive symptoms on the effectiveness of cognitive functions was observed. The ED-I group recorded better results compared to the rDD group in terms of the speed of information processing, visual-spatial and auditory-verbal memory and executive functions, auditory-verbal immediate and delayed memory, ability to learn and verbal fluency. The same differences were observed with respect to the patients from the ED-I group and the patients with the second episode of depression (ED-II) in the course of rDD. There are significant differences in cognitive functioning of patients with a depressive episode and recurrent depressive disorders. These differences are already visible from the second episode of a major depressive disorder. Memory, verbal fluency and frontal functions are reduced.
The Influence of Age-Related Differences in Prior Knowledge and Attentional Refreshing Opportunities on Episodic Memory.

PubMed

Loaiza, Vanessa M; Rhodes, Matthew G; Anglin, Julia

2015-09-01

The assumption that working memory (WM) is embedded within long-term memory suggests that the effectiveness of switching information between activated states in WM (i.e., attentional refreshing) may depend on whether that information is semantically relevant. Given that older adults often have greater general knowledge than younger adults, age-related deficits in episodic memory (EM) could be ameliorated by studying information that has existing semantic representations compared with unknown information. Younger and older adults completed a modified operation span task that varied the number of refreshing opportunities. The memoranda used were equally known to younger and older adults (neutral words; e.g., father), better known to older adults than younger adults (dated words; e.g., mirth), or unknown to both groups (unknown words; e.g., cobot). Results for immediate and delayed recall indicated an age-related improvement for dated memoranda and no age difference for unknown memoranda. Furthermore, refreshing opportunities predicted delayed recall of neutral memoranda more strongly for younger adults than older adults, whereas older adults' recall advantage for dated memoranda was explained by their prior knowledge and not refreshing opportunities. The results suggest that older adults' EM deficits could potentially be ameliorated by incorporating their superior knowledge to supplement relatively ineffective attentional refreshing in WM. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Divided attention improves delayed, but not immediate retrieval of a consolidated memory.

PubMed

Kessler, Yoav; Vandermorris, Susan; Gopie, Nigel; Daros, Alexander; Winocur, Gordon; Moscovitch, Morris

2014-01-01

A well-documented dissociation between memory encoding and retrieval concerns the role of attention in the two processes. The typical finding is that divided attention (DA) during encoding impairs future memory, but retrieval is relatively robust to attentional manipulations. However, memory research in the past 20 years had demonstrated that retrieval is a memory-changing process, in which the strength and availability of information are modified by various characteristics of the retrieval process. Based on this logic, several studies examined the effects of DA during retrieval (Test 1) on a future memory test (Test 2). These studies yielded inconsistent results. The present study examined the role of memory consolidation in accounting for the after-effect of DA during retrieval. Initial learning required a classification of visual stimuli, and hence involved incidental learning. Test 1 was administered 24 hours after initial learning, and therefore required retrieval of consolidated information. Test 2 was administered either immediately following Test 1 or after a 24-hour delay. Our results show that the effect of DA on Test 2 depended on this delay. DA during Test 1 did not affect performance on Test 2 when it was administered immediately, but improved performance when Test 2 was given 24-hours later. The results are consistent with other findings showing long-term benefits of retrieval difficulty. Implications for theories of reconsolidation in human episodic memory are discussed.
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.
Contribution of neurocognition to 18-month employment outcomes in first-episode psychosis.

PubMed

Karambelas, George J; Cotton, Sue M; Farhall, John; Killackey, Eóin; Allott, Kelly A

2017-10-27

To examine whether baseline neurocognition predicts vocational outcomes over 18 months in patients with first-episode psychosis enrolled in a randomized controlled trial of Individual Placement and Support or treatment as usual. One-hundred and thirty-four first-episode psychosis participants completed an extensive neurocognitive battery. Principal axis factor analysis using PROMAX rotation was used to determine the underlying structure of the battery. Setwise (hierarchical) multiple linear and logistic regressions were used to examine predictors of (1) total hours employed over 18 months and (2) employment status, respectively. Neurocognition factors were entered in the models after accounting for age, gender, premorbid IQ, negative symptoms, treatment group allocation and employment status at baseline. Five neurocognitive factors were extracted: (1) processing speed, (2) verbal learning and memory, (3) knowledge and reasoning, (4) attention and working memory and (5) visual organization and memory. Employment status over 18 months was not significantly predicted by any of the predictors in the final model. Total hours employed over 18 months were significantly predicted by gender (P = .027), negative symptoms (P = .032) and verbal learning and memory (P = .040). Every step of the regression model was a significant predictor of total hours worked overall (final model: P = .013). Verbal learning and memory, negative symptoms and gender were implicated in duration of employment in first-episode psychosis. The other neurocognitive domains did not significantly contribute to the prediction of vocational outcomes over 18 months. Interventions targeting verbal memory may improve vocational outcomes in early psychosis. © 2017 John Wiley & Sons Australia, Ltd.
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.
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.
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.
48. Associations Between Electrophysiological Measures of Selective Attention and Neurocognitive Measures of Working Memory and Attention in Antipsychotic-Naive, First-Episode Schizophrenia Patients

PubMed Central

Kruiper, Caitlyn; Fagerlund, Birgitte; Nielsen, Mette Ø.; Düring, Signe; Jensen, Maria H.; Ebdrup, Bjørn H.; Glenthøj, Birte Y.; Oranje, Bob

2017-01-01

Abstract Background: Deficits in attention and working memory are already present in early stages of schizophrenia. The P3a and b event related brain potentials (ERPs) are believed to underlie processes of attention and working memory, but, only limited research has been performed on the associations between these psychophysiological and cognitive deficits, particularly in the early stages of schizophrenia. We aimed to investigate associations between P3a and P3b amplitudes and measures of attention and working memory in a large cohort of antipsychotic-naive, first-episode schizophrenia patients (AN-FES) and age and sex-matched healthy controls (HC). Methods: Eighty-three AN-FES patients and 108 HC, matched for age and gender, were assessed for their P3a and b amplitude and latency with the selective attention paradigm from the Copenhagen Psychophysiological Test Battery (CPTB). In addition, the Spatial Working Memory (SWM) and Rapid Visual Information Processing test (RVP) from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were used to assess working memory and attention. Outcome measure for the SWM was Strategy, wherein a low score represents a more effective strategy. For the RVP, we used the A’ measure as outcome. This measure represents how well the participant is able to detect target sequences. Results: P3a and P3b amplitudes were significantly reduced in our AN-FES patients compared to HC. In addition, the P3a peak latency was earlier in the AN-FES patients than in HC, while P3b latency did not differ between the groups. Furthermore, AN-FES patients scored significantly lower on the SWM task and the RVP compared to HC. A positive association was found between RVP and P3b in our total group. However, this effect disappeared when split into the two subgroups. In contrast, SWM was positively associated with P3b in HC, while this effect was neither present in AN-FES nor in the total group. Conclusion: Our results provide evidence for P3a and P3b amplitude reductions as well as neurocognitive deficits in AN-FES patients compared to age and gender matched HC. This supports previous data that electrophysiological and neurocognitive deficits already exist in early stages of schizophrenia, and are not due to use of antipsychotics. Our data support significant yet rather weak associations between P3b amplitude and both working memory and attention, although the association between working memory and P3b was only found in HC and not in AN-FES.
Cognitive training with casual video games: points to consider

PubMed Central

Baniqued, Pauline L.; Kranz, Michael B.; Voss, Michelle W.; Lee, Hyunkyu; Cosman, Joshua D.; Severson, Joan; Kramer, Arthur F.

2014-01-01

Brain training programs have proliferated in recent years, with claims that video games or computer-based tasks can broadly enhance cognitive function. However, benefits are commonly seen only in trained tasks. Assessing generalized improvement and practicality of laboratory exercises complicates interpretation and application of findings. In this study, we addressed these issues by using active control groups, training tasks that more closely resemble real-world demands and multiple tests to determine transfer of training. We examined whether casual video games can broadly improve cognition, and selected training games from a study of the relationship between game performance and cognitive abilities. A total of 209 young adults were randomized into a working memory–reasoning group, an adaptive working memory–reasoning group, an active control game group, and a no-contact control group. Before and after 15 h of training, participants completed tests of reasoning, working memory, attention, episodic memory, perceptual speed, and self-report measures of executive function, game experience, perceived improvement, knowledge of brain training research, and game play outside the laboratory. Participants improved on the training games, but transfer to untrained tasks was limited. No group showed gains in reasoning, working memory, episodic memory, or perceptual speed, but the working memory–reasoning groups improved in divided attention, with better performance in an attention-demanding game, a decreased attentional blink and smaller trail-making costs. Perceived improvements did not differ across training groups and those with low reasoning ability at baseline showed larger gains. Although there are important caveats, our study sheds light on the mixed effects in the training and transfer literature and offers a novel and potentially practical training approach. Still, more research is needed to determine the real-world benefits of computer programs such as casual games. PMID:24432009

Reading Aloud and Solving Simple Arithmetic Calculation Intervention (Learning Therapy) Improves Inhibition, Verbal Episodic Memory, Focus Attention and Processing Speed in Healthy Elderly People: Evidence from a Randomized Controlled Trial

PubMed Central

Nouchi, Rui; Taki, Yasuyuki; Takeuchi, Hikaru; Nozawa, Takayuki; Sekiguchi, Atsushi; Kawashima, Ryuta

2016-01-01

Background: Previous reports have described that simple cognitive training using reading aloud and solving simple arithmetic calculations, so-called “learning therapy”, can improve executive functions and processing speed in the older adults. Nevertheless, it is not well-known whether learning therapy improve a wide range of cognitive functions or not. We investigated the beneficial effects of learning therapy on various cognitive functions in healthy older adults. Methods: We used a single-blinded intervention with two groups (learning therapy group: LT and waiting list control group: WL). Sixty-four elderly were randomly assigned to LT or WL. In LT, participants performed reading Japanese aloud and solving simple calculations training tasks for 6 months. WL did not participate in the intervention. We measured several cognitive functions before and after 6 months intervention periods. Results: Compared to WL, results revealed that LT improved inhibition performance in executive functions (Stroop: LT (Mean = 3.88) vs. WL (Mean = 1.22), adjusted p = 0.013 and reverse Stroop LT (Mean = 3.22) vs. WL (Mean = 1.59), adjusted p = 0.015), verbal episodic memory (Logical Memory (LM): LT (Mean = 4.59) vs. WL (Mean = 2.47), adjusted p = 0.015), focus attention (D-CAT: LT (Mean = 2.09) vs. WL (Mean = −0.59), adjusted p = 0.010) and processing speed compared to the WL control group (digit symbol coding: LT (Mean = 5.00) vs. WL (Mean = 1.13), adjusted p = 0.015 and Symbol Search (SS): LT (Mean = 3.47) vs. WL (Mean = 1.81), adjusted p = 0.014). Discussion: This randomized controlled trial (RCT) can be showed the benefit of LT on inhibition of executive functions, verbal episodic memory, focus attention and processing speed in healthy elderly people. Our results were discussed under overlapping hypothesis. PMID:27242481
Reading Aloud and Solving Simple Arithmetic Calculation Intervention (Learning Therapy) Improves Inhibition, Verbal Episodic Memory, Focus Attention and Processing Speed in Healthy Elderly People: Evidence from a Randomized Controlled Trial.

PubMed

Nouchi, Rui; Taki, Yasuyuki; Takeuchi, Hikaru; Nozawa, Takayuki; Sekiguchi, Atsushi; Kawashima, Ryuta

2016-01-01

Previous reports have described that simple cognitive training using reading aloud and solving simple arithmetic calculations, so-called "learning therapy", can improve executive functions and processing speed in the older adults. Nevertheless, it is not well-known whether learning therapy improve a wide range of cognitive functions or not. We investigated the beneficial effects of learning therapy on various cognitive functions in healthy older adults. We used a single-blinded intervention with two groups (learning therapy group: LT and waiting list control group: WL). Sixty-four elderly were randomly assigned to LT or WL. In LT, participants performed reading Japanese aloud and solving simple calculations training tasks for 6 months. WL did not participate in the intervention. We measured several cognitive functions before and after 6 months intervention periods. Compared to WL, results revealed that LT improved inhibition performance in executive functions (Stroop: LT (Mean = 3.88) vs. WL (Mean = 1.22), adjusted p = 0.013 and reverse Stroop LT (Mean = 3.22) vs. WL (Mean = 1.59), adjusted p = 0.015), verbal episodic memory (Logical Memory (LM): LT (Mean = 4.59) vs. WL (Mean = 2.47), adjusted p = 0.015), focus attention (D-CAT: LT (Mean = 2.09) vs. WL (Mean = -0.59), adjusted p = 0.010) and processing speed compared to the WL control group (digit symbol coding: LT (Mean = 5.00) vs. WL (Mean = 1.13), adjusted p = 0.015 and Symbol Search (SS): LT (Mean = 3.47) vs. WL (Mean = 1.81), adjusted p = 0.014). This randomized controlled trial (RCT) can be showed the benefit of LT on inhibition of executive functions, verbal episodic memory, focus attention and processing speed in healthy elderly people. Our results were discussed under overlapping hypothesis.
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
Motor Skills and Exercise Capacity Are Associated with Objective Measures of Cognitive Functions and Academic Performance in Preadolescent Children.

PubMed

Geertsen, Svend Sparre; Thomas, Richard; Larsen, Malte Nejst; Dahn, Ida Marie; Andersen, Josefine Needham; Krause-Jensen, Matilde; Korup, Vibeke; Nielsen, Claus Malta; Wienecke, Jacob; Ritz, Christian; Krustrup, Peter; Lundbye-Jensen, Jesper

2016-01-01

To investigate associations between motor skills, exercise capacity and cognitive functions, and evaluate how they correlate to academic performance in mathematics and reading comprehension using standardised, objective tests. This cross-sectional study included 423 Danish children (age: 9.29±0.35 years, 209 girls). Fine and gross motor skills were evaluated in a visuomotor accuracy-tracking task, and a whole-body coordination task, respectively. Exercise capacity was estimated from the Yo-Yo intermittent recovery level 1 children's test (YYIR1C). Selected tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were used to assess different domains of cognitive functions, including sustained attention, spatial working memory, episodic and semantic memory, and processing speed. Linear mixed-effects models were used to investigate associations between these measures and the relationship with standard tests of academic performance in mathematics and reading comprehension. Both fine and gross motor skills were associated with better performance in all five tested cognitive domains (all P<0.001), whereas exercise capacity was only associated with better sustained attention (P<0.046) and spatial working memory (P<0.038). Fine and gross motor skills (all P<0.001), exercise capacity and cognitive functions such as working memory, episodic memory, sustained attention and processing speed were all associated with better performance in mathematics and reading comprehension. The data demonstrate that fine and gross motor skills are positively correlated with several aspects of cognitive functions and with academic performance in both mathematics and reading comprehension. Moreover, exercise capacity was associated with academic performance and performance in some cognitive domains. Future interventions should investigate associations between changes in motor skills, exercise capacity, cognitive functions, and academic performance to elucidate the causality of these associations.
Motor Skills and Exercise Capacity Are Associated with Objective Measures of Cognitive Functions and Academic Performance in Preadolescent Children

PubMed Central

Thomas, Richard; Larsen, Malte Nejst; Dahn, Ida Marie; Andersen, Josefine Needham; Krause-Jensen, Matilde; Korup, Vibeke; Nielsen, Claus Malta; Wienecke, Jacob; Ritz, Christian; Krustrup, Peter; Lundbye-Jensen, Jesper

2016-01-01

Objective To investigate associations between motor skills, exercise capacity and cognitive functions, and evaluate how they correlate to academic performance in mathematics and reading comprehension using standardised, objective tests. Methods This cross-sectional study included 423 Danish children (age: 9.29±0.35 years, 209 girls). Fine and gross motor skills were evaluated in a visuomotor accuracy-tracking task, and a whole-body coordination task, respectively. Exercise capacity was estimated from the Yo-Yo intermittent recovery level 1 children's test (YYIR1C). Selected tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were used to assess different domains of cognitive functions, including sustained attention, spatial working memory, episodic and semantic memory, and processing speed. Linear mixed-effects models were used to investigate associations between these measures and the relationship with standard tests of academic performance in mathematics and reading comprehension. Results Both fine and gross motor skills were associated with better performance in all five tested cognitive domains (all P<0.001), whereas exercise capacity was only associated with better sustained attention (P<0.046) and spatial working memory (P<0.038). Fine and gross motor skills (all P<0.001), exercise capacity and cognitive functions such as working memory, episodic memory, sustained attention and processing speed were all associated with better performance in mathematics and reading comprehension. Conclusions The data demonstrate that fine and gross motor skills are positively correlated with several aspects of cognitive functions and with academic performance in both mathematics and reading comprehension. Moreover, exercise capacity was associated with academic performance and performance in some cognitive domains. Future interventions should investigate associations between changes in motor skills, exercise capacity, cognitive functions, and academic performance to elucidate the causality of these associations. PMID:27560512
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.
The benefits of physical activities on cognitive and mental health in healthy and pathological aging.

PubMed

Blanchet, Sophie; Chikhi, Samy; Maltais, Désirée

2018-06-01

Aging is associated with a decreased efficiency of different cognitive functions as well as in the perceptive, physical and physiological changes. The age-related cognitive decline concerns mainly attention, executive control and episodic memory. Some factors such as being physically active protect against the age-related decline. This review will discuss how physical activity can positively affect the cognitive efficiency and mental health of older healthy individuals, and possibly reduces the risk of progression into dementia, and depression. Underlying neurophysiological mechanisms play an important role for improving attention and episodic memory, which are the most sensitive to the effects of aging. We also present recommendations for the management of physical activity for the prevention of cognitive deficits, and the reduction of depressive symptoms in older persons. Given the benefits of physical activity for the prevention of neurodegenerative disease and the improvement of the well-being, it appears to be an important low cost therapeutic approach that should be integrated into clinical practice.
Getting the hang of it: preferential gist over verbatim story recall and the roles of attentional capacity and the episodic buffer in Alzheimer disease.

PubMed

Foldi, Nancy S

2011-01-01

Story recall in Alzheimer disease (AD) is typically used as a measure of episodic memory, but the degree to which recall is dependent on available attentional resources is not fully understood. The current study investigated how measures of attention were associated to verbatim recall (exact reproduction) or gist recall (relevant semantic meaning). Sixteen participants with AD and 16 age-matched healthy older adults recalled a story on immediate free recall and recognition. Controls recalled more units overall than AD. A group X response interaction revealed more gist than verbatim recall in AD, but those with mild disease generated approximately the same number gist responses as controls. For each group, qualitatively different attentional resources were associated with recall units. In controls, verbatim units correlated positively with primacy serial position items of the California Verbal Learning Test II (CVLTII), suggesting that episodic buffer resources may be associated with story recall. In AD, gist units were positively correlated with digits forward, but inversely related to the CVLTII primacy region items, suggesting reliance on low-level capacity resources. Possible explanations of the impaired performance in AD may be a bias in favor of gist processing, poor verbatim encoding, and/or processing failure at the level of the episodic buffer.
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.
Covert retrieval in working memory impacts the phenomenological characteristics remembered during episodic memory.

PubMed

Loaiza, Vanessa M; Borovanska, Borislava M

2018-01-01

Much research has investigated the qualitative experience of retrieving events from episodic memory (EM). The present study investigated whether covert retrieval in WM increases the phenomenological characteristics that participants find memorable in EM using tasks that distract attention from the maintenance of memoranda (i.e., complex span; Experiment 1) relative to tasks that do not (i.e., short or long list lengths of simple span; Experiments 1 and 2). Participants rated the quality of the phonological, semantic, and temporal-contextual characteristics remembered during a delayed memory characteristics questionnaire (MCQ). Whereas an advantage of the complex over simple span items was observed for each characteristic (Experiment 1), no such difference was observed between short and long trials of simple span (Experiment 2). These results are consistent with the view that covert retrieval in WM promotes content-context bindings that are later accessible from EM for both objective performance and subjective details of the remembered information. Copyright © 2017 Elsevier Inc. All rights reserved.
Mind wandering and retrieval from episodic memory: a pilot event-related potential study.

PubMed

Riby, Leigh Martin; Smallwood, Jonathan; Gunn, Valerie P

2008-06-01

The present study investigated the effects of mind wandering (task-unrelated thought) on the subcomponents of episodic memory as reflected by event-related potentials (ERPs). Specifically, individual differences in the pattern of ERP episodic 'old/new' effects (left-parietal, right-frontal and central-negativity effects) were examined across groups of participants experiencing either high or low frequencies of task-unrelated thought during encoding. Twenty participants studied lists of words and line drawings in one of two contexts (red versus green coloured boxes). At test, participants discriminated between target (old words or line drawings presented in one colour) and nontargets (old items from the other colour and new items). On completion of the memory task, participants completed the 'thinking' component of the Dundee Stress State Questionnaire to provide a retrospective measure of task-unrelated thought. Behavioural data indicated that irrespective of the presence of task-unrelated thought, participants were able to complete the memory task equally well. However, an analysis of ERPs across High and Low task-unrelated thought groups revealed differences in retrieval strategy. Those individuals with infrequent episodes of task-unrelated thought at study used a 'pure' recollection strategy (left-parietal effect only). Conversely, those participants experiencing frequent episodes of task-unrelated thought were unable to recollect the stimuli with ease, as indexed by a diminished parietal effect. As a consequence, these participants employed additional strategic processes for task completion, as indexed by an elevated amplitude of central negativity effects. These data are consistent with the decoupling hypothesis of mind wandering which suggests impaired recollection when attention becomes directed away from the task.
Factors modulating the effect of divided attention during retrieval of words.

PubMed

Fernandes, Myra A; Moscovitch, Morris

2002-07-01

In this study, we examined variables modulating interference effects on episodic memory under divided attention conditions during retrieval for a list of unrelated words. In Experiment 1, we found that distracting tasks that required animacy or syllable decisions to visually presented words, without a memory load, produced large interference on free recall performance. In Experiment 2, a distracting task requiring phonemic decisions about nonsense words produced a far larger interference effect than one that required semantic decisions about pictures. In Experiment 3, we replicated the effect of the nonsense-word distracting task on memory and showed that an equally resource-demanding picture-based task produced significant interference with memory retrieval, although the effect was smaller in magnitude. Taken together, the results suggest that free recall is disrupted by competition for phonological or word-form representations during retrieval and, to a lesser extent, by competition for semantic representations.
Exercise effects on cognitive functioning in young adults with first-episode psychosis: FitForLife.

PubMed

Hallgren, Mats; Skott, Maria; Ekblom, Örjan; Firth, Joseph; Schembri, Adrian; Forsell, Yvonne

2018-05-06

Exercise has mood-enhancing effects and can improve cognitive functioning, but the effects in first-episode psychosis (FEP) remain understudied. We examined the feasibility and cognitive effects of exercise in FEP. Multi-center, open-label intervention study. Ninety-one outpatients with FEP (mean age = 30 years, 65% male) received usual care plus a 12-week supervised circuit-training program, consisting of high-volume resistance exercises, aerobic training, and stretching. Primary study outcome was cognitive functioning assessed by Cogstate Brief Battery (processing speed, attention, visual learning, working memory) and Trailmaking A and B tasks (visual attention and task shifting). Within-group changes in cognition were assessed using paired sample t tests with effect sizes (Hedges' g) reported for significant values. Relationships between exercise frequency and cognitive improvement were assessed using analysis of covariance. Moderating effects of gender were explored with stratified analyses. Participants exercised on average 13.5 (s.d. = 11.7) times. Forty-eight percent completed 12 or more sessions. Significant post-intervention improvements were seen for processing speed, visual learning, and visual attention; all with moderate effect sizes (g = 0.47-0.49, p < 0.05). Exercise participation was also associated with a positive non-significant trend for working memory (p < 0.07). Stratified analyses indicated a moderating effect of gender. Positive changes were seen among females only for processing speed, visual learning, working memory, and visual attention (g = 0.43-0.69). A significant bivariate correlation was found between total training frequency and improvements in visual attention among males (r = 0.40, p < 0.05). Supported physical exercise is a feasible and safe adjunct treatment for FEP with potential cognitive benefits, especially among females.
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.
Domain-general signals in the cingulo-opercular network for visuospatial attention and episodic memory

PubMed Central

Sestieri, Carlo; Corbetta, Maurizio; Spadone, Sara; Romani, Gian Luca; Shulman, Gordon L.

2014-01-01

We investigated the functional properties of a previously described cingulo-opercular network (CON) putatively involved in cognitive control. Analyses of common fMRI task-evoked activity during perceptual and episodic memory search tasks that differently recruited the dorsal attention (DAN) and default mode network (DMN) established the generality of this network. Regions within the CON (anterior insula/frontal operculum and anterior cingulate/presupplementary cortex) displayed sustained signals during extended periods in which participants searched for behaviourally relevant information in a dynamically changing environment or from episodic memory in the absence of sensory stimulation. The CON was activated during all phases of both tasks, which involved trial initiation, target detection, decision and response, indicating its consistent involvement in a broad range of cognitive processes. Functional connectivity analyses showed that the CON flexibly linked with the DAN or DMN regions during perceptual or memory search, respectively. Aside from the CON, only a limited number of regions, including the lateral prefrontal cortex, showed evidence of domain-general, sustained activity, although in some cases the common activations may have reflected the functional-anatomical variability of domain-specific regions rather than a true domain-generality. These additional regions also showed task-dependent functional connectivity with the DMN and DAN, suggesting that this feature is not a specific marker of cognitive control. Finally, multivariate clustering analyses separated the CON from other fronto-parietal regions previously associated with cognitive control, indicating a unique fingerprint. We conclude that the CON’s functional properties and interactions with other brain regions support a broad role in cognition, consistent with its characterization as a task-control network. PMID:24144246
Learning to remember: The early ontogeny of episodic memory☆

PubMed Central

Mullally, Sinéad L.; Maguire, Eleanor A.

2014-01-01

Over the past 60 years the neural correlates of human episodic memory have been the focus of intense neuroscientific scrutiny. By contrast, neuroscience has paid substantially less attention to understanding the emergence of this neurocognitive system. In this review we consider how the study of memory development has evolved. In doing so, we concentrate primarily on the first postnatal year because it is within this time window that the most dramatic shifts in scientific opinion have occurred. Moreover, this time frame includes the critical age (∼9 months) at which human infants purportedly first begin to demonstrate rudimentary hippocampal-dependent memory. We review the evidence for and against this assertion, note the lack of direct neurocognitive data speaking to this issue, and question how demonstrations of exuberant relational learning and memory in infants as young as 3-months old can be accommodated within extant models. Finally, we discuss whether current impasses in the infant memory literature could be leveraged by making greater use of neuroimaging techniques, such as magnetic resonance imaging (MRI), which have been deployed so successfully in adults. PMID:24480487
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
Measurement invariance of neuropsychological tests in diverse older persons.

PubMed

Mungas, Dan; Widaman, Keith F; Reed, Bruce R; Tomaszewski Farias, Sarah

2011-03-01

Comparability of meaning of neuropsychological test results across ethnic, linguistic, and cultural groups is important for clinicians challenged with assessing increasing numbers of older ethnic minorities. We examined the dimensional structure of a neuropsychological test battery in linguistically and demographically diverse older adults. The Spanish and English Neuropsychological Assessment Scales (SENAS), developed to provide psychometrically sound measures of cognition for multiethnic and multilingual applications, was administered to a community dwelling sample of 760 Whites, 443 African Americans, 451 English-speaking Hispanics, and 882 Spanish-speaking Hispanics. Cognitive function spanned a broad range from normal to mildly impaired to demented. Multiple group confirmatory factor analysis was used to examine equivalence of the dimensional structure for the SENAS across the groups defined by language and ethnicity. Covariance among 16 SENAS tests was best explained by five cognitive dimensions corresponding to episodic memory, semantic memory/language, spatial ability, attention/working memory, and verbal fluency. Multiple Group confirmatory factor analysis supported a common dimensional structure in the diverse groups. Measures of episodic memory showed the most compelling evidence of measurement equivalence across groups. Measurement equivalence was observed for most but not all measures of semantic memory/language and spatial ability. Measures of attention/working memory defined a common dimension in the different groups, but results suggest that scores are not strictly comparable across groups. These results support the applicability of the SENAS for use with multiethnic and bilingual older adults, and more broadly, provide evidence of similar dimensions of cognition in the groups represented in the study. (c) 2011 APA, all rights reserved
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.

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
Thalamic pathology and memory loss in early Alzheimer’s disease: moving the focus from the medial temporal lobe to Papez circuit

PubMed Central

Pralus, Agathe; Nelson, Andrew J. D.; Hornberger, Michael

2016-01-01

Abstract It is widely assumed that incipient protein pathology in the medial temporal lobe instigates the loss of episodic memory in Alzheimer’s disease, one of the earliest cognitive deficits in this type of dementia. Within this region, the hippocampus is seen as the most vital for episodic memory. Consequently, research into the causes of memory loss in Alzheimer’s disease continues to centre on hippocampal dysfunction and how disease-modifying therapies in this region can potentially alleviate memory symptomology. The present review questions this entrenched notion by bringing together findings from post-mortem studies, non-invasive imaging (including studies of presymptomatic, at-risk cases) and genetically modified animal models. The combined evidence indicates that the loss of episodic memory in early Alzheimer’s disease reflects much wider neurodegeneration in an extended mnemonic system (Papez circuit), which critically involves the limbic thalamus. Within this system, the anterior thalamic nuclei are prominent, both for their vital contributions to episodic memory and for how these same nuclei appear vulnerable in prodromal Alzheimer’s disease. As thalamic abnormalities occur in some of the earliest stages of the disease, the idea that such changes are merely secondary to medial temporal lobe dysfunctions is challenged. This alternate view is further strengthened by the interdependent relationship between the anterior thalamic nuclei and retrosplenial cortex, given how dysfunctions in the latter cortical area provide some of the earliest in vivo imaging evidence of prodromal Alzheimer’s disease. Appreciating the importance of the anterior thalamic nuclei for memory and attention provides a more balanced understanding of Alzheimer’s disease. Furthermore, this refocus on the limbic thalamus, as well as the rest of Papez circuit, would have significant implications for the diagnostics, modelling, and experimental treatment of cognitive symptoms in Alzheimer’s disease. PMID:27190025
Attention promotes episodic encoding by stabilizing hippocampal representations

PubMed Central

Aly, Mariam; Turk-Browne, Nicholas B.

2016-01-01

Attention influences what is later remembered, but little is known about how this occurs in the brain. We hypothesized that behavioral goals modulate the attentional state of the hippocampus to prioritize goal-relevant aspects of experience for encoding. Participants viewed rooms with paintings, attending to room layouts or painting styles on different trials during high-resolution functional MRI. We identified template activity patterns in each hippocampal subfield that corresponded to the attentional state induced by each task. Participants then incidentally encoded new rooms with art while attending to the layout or painting style, and memory was subsequently tested. We found that when task-relevant information was better remembered, the hippocampus was more likely to have been in the correct attentional state during encoding. This effect was specific to the hippocampus, and not found in medial temporal lobe cortex, category-selective areas of the visual system, or elsewhere in the brain. These findings provide mechanistic insight into how attention transforms percepts into memories. PMID:26755611
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.
Neural Dynamics Associated with Semantic and Episodic Memory for Faces: Evidence from Multiple Frequency Bands

ERIC Educational Resources Information Center

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

2010-01-01

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…
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.
The effects of glucose ingestion and glucose regulation on memory performance in older adults with mild cognitive impairment.

PubMed

Riby, L M; Marriott, A; Bullock, R; Hancock, J; Smallwood, J; McLaughlin, J

2009-04-01

Previous research investigating the impact of glucose ingestion and/or improvements in glucose regulation has found selective cognitive facilitation on episodic memory tasks in successful ageing and dementia. The present study aimed to extend this research to mild cognitive impairment (MCI). In a repeated-measures design, 24 older adults with and 24 older adults without MCI performed a battery of memory and attention tasks after 25 g of glucose or a sweetness matched placebo. In addition, to assess the impact of individual differences in glucose regulation, blood glucose measurements were taken throughout the testing session. Consistent with previous research, cognitive facilitation was observed for episodic memory tasks only in both successful ageing and MCI. Older adults with MCI had a similar glucose regulatory response as controls but their fasting levels were elevated. Notably, higher levels of blood glucose were associated with impaired memory performance in both the glucose and placebo conditions. Importantly, both blood glucose and memory performance indices were significant predictors of MCI status. The utility of glucose supplementation and the use of glucose regulation as a biological marker are discussed in relation to these data.
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
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…
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.
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.
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.
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.
Cognitive Contributions of the Ventral Parietal Cortex: An Integrative Theoretical Account

PubMed Central

Cabeza, Roberto; Ciaramelli, Elisa; Moscovitch, Morris

2012-01-01

Although ventral parietal cortex (VPC) activations can be found in a variety of cognitive domains, these activations have been typically attributed to cognitive operations specific to each domain. In this article, we propose a hypothesis that can account for VPC activations across all the cognitive domains reviewed. We first review VPC activations in the domains of perceptual and motor reorienting, episodic memory retrieval, language and number processing, theory of mind, and episodic memory encoding. Then, we consider the localization of VPC activations across domains, and conclude that they are largely overlapping with some differences around the edges. Finally, we assess how well four different hypotheses of VPC function can explain findings in various domains, and conclude that a bottom-up attention hypothesis provides the most complete and parsimonious account. PMID:22609315

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.
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.
The Role of Attention for Context-Context Binding of Intrinsic and Extrinsic Features

ERIC Educational Resources Information Center

Boywitt, C. Dennis; Meiser, Thorsten

2012-01-01

There is converging evidence that the feeling of conscious recollection is usually accompanied by the bound retrieval of context features of the encoding episode (e.g., Meiser, Sattler, & Weiber, 2008). Recently, however, important limiting conditions have been identified for the binding between context features in memory. For example, focusing on…
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.
Glucose administration prior to a divided attention task improves tracking performance but not word recognition: evidence against differential memory enhancement?

PubMed

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

2009-01-01

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

PubMed

Kirova, Anna-Mariya; Bays, Rebecca B; Lagalwar, Sarita

2015-01-01

Alzheimer's disease (AD) is a progressive neurodegenerative disease marked by deficits in episodic memory, working memory (WM), and executive function. Examples of executive dysfunction in AD include poor selective and divided attention, failed inhibition of interfering stimuli, and poor manipulation skills. Although episodic deficits during disease progression have been widely studied and are the benchmark of a probable AD diagnosis, more recent research has investigated WM and executive function decline during mild cognitive impairment (MCI), also referred to as the preclinical stage of AD. MCI is a critical period during which cognitive restructuring and neuroplasticity such as compensation still occur; therefore, cognitive therapies could have a beneficial effect on decreasing the likelihood of AD progression during MCI. Monitoring performance on working memory and executive function tasks to track cognitive function may signal progression from normal cognition to MCI to AD. The present review tracks WM decline through normal aging, MCI, and AD to highlight the behavioral and neurological differences that distinguish these three stages in an effort to guide future research on MCI diagnosis, cognitive therapy, and AD prevention.
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.
Methylphenidate and Memory and Attention Adaptation Training for Persistent Cognitive Symptoms after Traumatic Brain Injury: A Randomized, Placebo-Controlled Trial.

PubMed

McDonald, Brenna C; Flashman, Laura A; Arciniegas, David B; Ferguson, Robert J; Xing, Li; Harezlak, Jaroslaw; Sprehn, Gwen C; Hammond, Flora M; Maerlender, Arthur C; Kruck, Carrie L; Gillock, Karen L; Frey, Kim; Wall, Rachel N; Saykin, Andrew J; McAllister, Thomas W

2017-08-01

The purpose of this multicenter, prospective, randomized, placebo-controlled study was to evaluate and compare the efficacy of two cognitive rehabilitation interventions (Memory and Attention Adaptation Training (MAAT) and Attention Builders Training (ABT)), with and without pharmacological enhancement (ie, with methylphenidate (MPH) or placebo), for treating persistent cognitive problems after traumatic brain injury (TBI). Adults with a history of TBI at least 4 months before study enrollment with either objective cognitive deficits or subjective cognitive complaints were randomized to receive MPH or placebo and MAAT or ABT, yielding four treatment combinations: MAAT/MPH (N=17), ABT/MPH (N=19), MAAT/placebo (N=17), and ABT/placebo (N=18). Assessments were conducted pre-treatment (baseline) and after 6 weeks of treatment (post treatment). Outcome measures included scores on neuropsychological measures and subjective rating scales. Statistical analyses used linear regression models to predict post-treatment scores for each outcome variable by treatment type, adjusting for relevant covariates. Statistically significant (P<0.05) treatment-related improvements in cognitive functioning were found for word-list learning (MAAT/placebo>ABT/placebo), nonverbal learning (MAAT/MPH>MAAT/placebo and MAAT/MPH>ABT/MPH), and auditory working memory and divided attention (MAAT/MPH>ABT/MPH). These results suggest that combined treatment with metacognitive rehabilitation (MAAT) and pharmacotherapy (MPH) can improve aspects of attention, episodic and working memory, and executive functioning after TBI.
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
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.
Neuropsychological function and suicidal behavior: attention control, memory and executive dysfunction in suicide attempt.

PubMed

Keilp, J G; Gorlyn, M; Russell, M; Oquendo, M A; Burke, A K; Harkavy-Friedman, J; Mann, J J

2013-03-01

Executive dysfunction, distinct from other cognitive deficits in depression, has been associated with suicidal behavior. However, this dysfunction is not found consistently across samples. Medication-free subjects with DSM-IV major depressive episode (major depressive disorder and bipolar type I disorder) and a past history of suicidal behavior (n = 72) were compared to medication-free depressed subjects with no history of suicidal behavior (n = 80) and healthy volunteers (n = 56) on a battery of tests assessing neuropsychological functions typically affected by depression (motor and psychomotor speed, attention, memory) and executive functions reportedly impaired in suicide attempters (abstract/contingent learning, working memory, language fluency, impulse control). All of the depressed subjects performed worse than healthy volunteers on motor, psychomotor and language fluency tasks. Past suicide attempters, in turn, performed worse than depressed non-attempters on attention and memory/working memory tasks [a computerized Stroop task, the Buschke Selective Reminding Task (SRT), the Benton Visual Retention Test (VRT) and an N-back task] but not on other executive function measures, including a task associated with ventral prefrontal function (Object Alternation). Deficits were not accounted for by current suicidal ideation or the lethality of past attempts. A small subsample of those using a violent method in their most lethal attempt showed a pattern of poor executive performance. Deficits in specific components of attention control, memory and working memory were associated with suicidal behavior in a sample where non-violent attempt predominated. Broader executive dysfunction in depression may be associated with specific forms of suicidal behavior, rather than suicidal behavior per se.
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.

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
Role of glucose in chewing gum-related facilitation of cognitive function.

PubMed

Stephens, Richard; Tunney, Richard J

2004-10-01

This study tests the hypothesis that chewing gum leads to cognitive benefits through improved delivery of glucose to the brain, by comparing the cognitive performance effects of gum and glucose administered separately and together. Participants completed a battery of cognitive tests in a fully related 2 x 2 design, where one factor was Chewing Gum (gum vs. mint sweet) and the other factor was Glucose Co-administration (consuming a 25 g glucose drink vs. consuming water). For four tests (AVLT Immediate Recall, Digit Span, Spatial Span and Grammatical Transformation), beneficial effects of chewing and glucose were found, supporting the study hypothesis. However, on AVLT Delayed Recall, enhancement due to chewing gum was not paralleled by glucose enhancement, suggesting an alternative mechanism. The glucose delivery model is supported with respect to the cognitive domains: working memory, immediate episodic long-term memory and language-based attention and processing speed. However, some other mechanism is more likely to underlie the facilitatory effect of chewing gum on delayed episodic long-term memory.
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
Dissociation of long-term verbal memory and fronto-executive impairment in first-episode psychosis

PubMed Central

Leeson, V. C.; Robbins, T. W.; Franklin, C.; Harrison, M.; Harrison, I.; Ron, M. A.; Barnes, T. R. E.; Joyce, E. M.

2009-01-01

Background Verbal memory is frequently and severely affected in schizophrenia and has been implicated as a mediator of poor clinical outcome. Whereas encoding deficits are well demonstrated, it is unclear whether retention is impaired. This distinction is important because accelerated forgetting implies impaired consolidation attributable to medial temporal lobe (MTL) dysfunction whereas impaired encoding and retrieval implicates involvement of prefrontal cortex. Method We assessed a group of healthy volunteers (n=97) and pre-morbid IQ- and sex-matched first-episode psychosis patients (n=97), the majority of whom developed schizophrenia. We compared performance of verbal learning and recall with measures of visuospatial working memory, planning and attentional set-shifting, and also current IQ. Results All measures of performance, including verbal memory retention, a memory savings score that accounted for learning impairments, were significantly impaired in the schizophrenia group. The difference between groups for delayed recall remained even after the influence of learning and recall was accounted for. Factor analyses showed that, in patients, all variables except verbal memory retention loaded on a single factor, whereas in controls verbal memory and fronto-executive measures were separable. Conclusions The results suggest that IQ, executive function and verbal learning deficits in schizophrenia may reflect a common abnormality of information processing in prefrontal cortex rather than specific impairments in different cognitive domains. Verbal memory retention impairments, however, may have a different aetiology. PMID:19419594
The effects of the soluble guanylate cyclase stimulator riociguat on memory performance in healthy volunteers with a biperiden-induced memory impairment.

PubMed

Borghans, Laura G J M; Sambeth, Anke; Prickaerts, Jos; Ramaekers, Johannes G; Blokland, Arjan

2018-06-07

After stimulation with nitric oxide, soluble guanylate cyclase (sGC) produces cyclic guanosine monophosphate (cGMP), which stimulates an important signalling pathway for long-term potentiation (LTP). By upregulating cGMP, LTP could be stimulated and thereby enhancing memory processes. The present study investigated the effects of the sGC stimulator riociguat on cognition in healthy volunteers. Participants were pre-treated with and without biperiden, which impairs memory performance, to investigate the memory-enhancing effects of riociguat. Twenty volunteers participated in a double-blind placebo-controlled six-way crossover design with a cognitive test battery including the verbal learning task (VLT), n-back task, spatial memory test, the attention network test, and a reaction time task. Treatments were placebo and riociguat 0.5 mg, placebo and riociguat 1.0 mg, biperiden 2.0 mg and placebo, biperiden 2.0 mg and riociguat 0.5 mg and biperiden 2.0 mg and riociguat 1.0 mg. Blood pressure was found to be decreased and heart rate to be increased after administration of riociguat. Cognitive performance was not enhanced after administration of riociguat. Biperiden decreased episodic memory on the VLT, yet this deficit was not reversed by riociguat. This supports the notion that biperiden might be a valuable pharmacological model to induce episodic memory impairments as observed in AD/MCI.
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
Reduced memory and attention performance in a population-based sample of young adults with a moderate lifetime use of cannabis, ecstasy and alcohol.

PubMed

Indlekofer, F; Piechatzek, M; Daamen, M; Glasmacher, C; Lieb, R; Pfister, H; Tucha, O; Lange, K W; Wittchen, H U; Schütz, C G

2009-07-01

Regular use of illegal drugs is suspected to cause cognitive impairments. Two substances have received heightened attention: 3,4-methylenedioxymethamphetamine (MDMA or 'ecstasy') and delta-9-tetrahydrocannabinol (THC or 'cannabis'). Preclinical evidence, as well as human studies examining regular ecstasy consumers, indicated that ecstasy use may have negative effects on learning, verbal memory and complex attentional functions. Cannabis has also been linked to symptoms of inattention and deficits in learning and memory. Most of the published studies in this field of research recruited participants by means of newspaper advertisements or by using word-of-mouth strategies. Because participants were usually aware that their drug use was critical to the research design, this awareness may have caused selection bias or created expectation effects. Focussing on attention and memory, this study aimed to assess cognitive functioning in a community-based representative sample that was derived from a large-scale epidemiological study. Available data concerning drug use history allowed sampling of subjects with varying degrees of lifetime drug experiences. Cognitive functioning was examined in 284 young participants, between 22 and 34 years. In general, their lifetime drug experience was moderate. Participants completed a neuropsychological test battery, including measures for verbal learning, memory and various attentional functions. Linear regression analysis was performed to investigate the relationship between cognitive functioning and lifetime experience of drug use. Ecstasy and cannabis use were significantly related to poorer episodic memory function in a dose-related manner. For attentional measures, decrements of small effect sizes were found. Error measures in tonic and phasic alertness tasks, selective attention task and vigilance showed small but significant effects, suggesting a stronger tendency to experience lapses of attention. No indication for differences in reaction time was found. The results are consistent with decrements of memory and attentional performance described in previous studies. These effects are relatively small; however, it must be kept in mind that this study focussed on assessing young adults with moderate drug use from a population-based study.
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.
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 Ease of Language Understanding (ELU) model: theoretical, empirical, and clinical advances

PubMed Central

Rönnberg, Jerker; Lunner, Thomas; Zekveld, Adriana; Sörqvist, Patrik; Danielsson, Henrik; Lyxell, Björn; Dahlström, Örjan; Signoret, Carine; Stenfelt, Stefan; Pichora-Fuller, M. Kathleen; Rudner, Mary

2013-01-01

Working memory is important for online language processing during conversation. We use it to maintain relevant information, to inhibit or ignore irrelevant information, and to attend to conversation selectively. Working memory helps us to keep track of and actively participate in conversation, including taking turns and following the gist. This paper examines the Ease of Language Understanding model (i.e., the ELU model, Rönnberg, 2003; Rönnberg et al., 2008) in light of new behavioral and neural findings concerning the role of working memory capacity (WMC) in uni-modal and bimodal language processing. The new ELU model is a meaning prediction system that depends on phonological and semantic interactions in rapid implicit and slower explicit processing mechanisms that both depend on WMC albeit in different ways. It is based on findings that address the relationship between WMC and (a) early attention processes in listening to speech, (b) signal processing in hearing aids and its effects on short-term memory, (c) inhibition of speech maskers and its effect on episodic long-term memory, (d) the effects of hearing impairment on episodic and semantic long-term memory, and finally, (e) listening effort. New predictions and clinical implications are outlined. Comparisons with other WMC and speech perception models are made. PMID:23874273
Autobiographically significant concepts: more episodic than semantic in nature? An electrophysiological investigation of overlapping types of memory.

PubMed

Renoult, Louis; Davidson, Patrick S R; Schmitz, Erika; Park, Lillian; Campbell, Kenneth; Moscovitch, Morris; Levine, Brian

2015-01-01

A common assertion is that semantic memory emerges from episodic memory, shedding the distinctive contexts associated with episodes over time and/or repeated instances. Some semantic concepts, however, may retain their episodic origins or acquire episodic information during life experiences. The current study examined this hypothesis by investigating the ERP correlates of autobiographically significant (AS) concepts, that is, semantic concepts that are associated with vivid episodic memories. We inferred the contribution of semantic and episodic memory to AS concepts using the amplitudes of the N400 and late positive component, respectively. We compared famous names that easily brought to mind episodic memories (high AS names) against equally famous names that did not bring such recollections to mind (low AS names) on a semantic task (fame judgment) and an episodic task (recognition memory). Compared with low AS names, high AS names were associated with increased amplitude of the late positive component in both tasks. Moreover, in the recognition task, this effect of AS was highly correlated with recognition confidence. In contrast, the N400 component did not differentiate the high versus low AS names but, instead, was related to the amount of general knowledge participants had regarding each name. These results suggest that semantic concepts high in AS, such as famous names, have an episodic component and are associated with similar brain processes to those that are engaged by episodic memory. Studying AS concepts may provide unique insights into how episodic and semantic memory interact.
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.
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.
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…
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

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
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.
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.
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.
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
Episodic Visual Learning/Memory and Attentional Flexibility in Patients With Major Depressive Disorder After Clinically Effective Electroconvulsive Therapy.

PubMed

Kalogerakou, Stamatina; Oulis, Panagiotis; Anyfandi, Eleni; Konstantakopoulos, George; Papakosta, Vasiliki-Maria; Kontis, Dimitrios; Theochari, Eirini; Angelopoulos, Elias; Zervas, Ioannis M; Mellon, Robert C; Papageorgiou, Charalambos C; Tsaltas, Eleftheria

2015-12-01

This study is a follow-up of a previous one reporting that the neuropsychological profile of pharmacoresistant patients with major depressive disorder referred for electroconvulsive therapy (ECT, ECT group) contrasted with that of their pharmacorespondent counterparts (NECT group). The NECT group exhibited severe visuospatial memory and minor executive deficits; the ECT group presented the reverse pattern. In that same ECT group, the current follow-up study examined the effects of clinically effective ECT on both cognitive domains 2 months later. Fifteen ECT patients were administered Hamilton Depression (HAMD-24), Hamilton Anxiety (HAMA), Mini-Mental State Examination Scales and 5 tests of Cambridge Neuropsychological Test Automated Battery at intake (pre-ECT), end of ECT course (post-ECT), and 2 months thereafter (follow-up). Electroconvulsive therapy was effective in relieving clinical depression. After a post-ECT decline, the patients exhibited significant improvement in both Cambridge Neuropsychological Test Automated Battery, paired associate learning, and Stockings of Cambridge. By contrast, their major pre-ECT deficit in intra/extradimensional set shifting remained virtually unaffected. Our findings suggest that attentional flexibility deficits may constitute a neuropsychological trait-like feature of pharmacoresistant, ECT-referred major depressive disorder patients. However, this deficit does not seem generalized, given patient improvement in episodic visual learning/memory and some indication of improvement in spatial planning after ECT.
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.
Influence of schooling and age on cognitive performance in healthy older adults

PubMed Central

Bento-Torres, N.V.O.; Bento-Torres, J.; Tomás, A.M.; Costa, V.O.; Corrêa, P.G.R.; Costa, C.N.M.; Jardim, N.Y.V.; Picanço-Diniz, C.W.

2017-01-01

Few studies have examined the influence of a low level of schooling on age-related cognitive decline in countries with wide social and economic inequalities by using the Cambridge Automated Neuropsychological Test Battery (CANTAB). The aim of the present study was to assess the influence of schooling on age-related cognitive decline using unbiased cognitive tests. CANTAB allows cognitive assessment across cultures and education levels with reduced interference of the examiner during data acquisition. Using two-way ANOVA, we assessed the influences of age and education on test scores of old adults (61–84 years of age). CANTAB tests included: Visual Sustained Attention, Reaction Time, Spatial Working Memory, Learning and Episodic Memory. All subjects had a minimum visual acuity of 20/30 (Snellen Test), no previous or current history of traumatic brain/head trauma, stroke, language impairment, chronic alcoholism, neurological diseases, memory problems or depressive symptoms, and normal scores on the Mini Mental State Examination (MMSE). Subjects were grouped according to education level (1 to 7 and ≥8 years of schooling) and age (60–69 and ≥70 years). Low schooling level was associated with significantly lower performance on visual sustained attention, learning and episodic memory, reaction time, and spatial working memory. Although reaction time was influenced by age, no significant results on post hoc analysis were detected. Our findings showed a significantly worse cognitive performance in volunteers with lower levels of schooling and suggested that formal education in early life must be included in the preventive public health agenda. In addition, we suggest that CANTAB may be useful to detect subtle cognitive changes in healthy aging. PMID:28355353
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.
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
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.
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.
Computational modeling of the negative priming effect based on inhibition patterns and working memory

PubMed Central

Chung, Dongil; Raz, Amir; Lee, Jaewon; Jeong, Jaeseung

2013-01-01

Negative priming (NP), slowing down of the response for target stimuli that have been previously exposed, but ignored, has been reported in multiple psychological paradigms including the Stroop task. Although NP likely results from the interplay of selective attention, episodic memory retrieval, working memory, and inhibition mechanisms, a comprehensive theoretical account of NP is currently unavailable. This lacuna may result from the complexity of stimuli combinations in NP. Thus, we aimed to investigate the presence of different degrees of the NP effect according to prime-probe combinations within a classic Stroop task. We recorded reaction times (RTs) from 66 healthy participants during Stroop task performance and examined three different NP subtypes, defined according to the type of the Stroop probe in prime-probe pairs. Our findings show significant RT differences among NP subtypes that are putatively due to the presence of differential disinhibition, i.e., release from inhibition. Among the several potential origins for differential subtypes of NP, we investigated the involvement of selective attention and/or working memory using a parallel distributed processing (PDP) model (employing selective attention only) and a modified PDP model with working memory (PDP-WM, employing both selective attention and working memory). Our findings demonstrate that, unlike the conventional PDP model, the PDP-WM successfully simulates different levels of NP effects that closely follow the behavioral data. This outcome suggests that working memory engages in the re-accumulation of the evidence for target response and induces differential NP effects. Our computational model complements earlier efforts and may pave the road to further insights into an integrated theoretical account of complex NP effects. PMID:24312046
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.
Topographical Organization of Attentional, Social, and Memory Processes in the Human Temporoparietal Cortex123

PubMed Central

Webb, Taylor W.; Kelly, Yin T.; Graziano, Michael S. A.

2016-01-01

Abstract The temporoparietal junction (TPJ) is activated in association with a large range of functions, including social cognition, episodic memory retrieval, and attentional reorienting. An ongoing debate is whether the TPJ performs an overarching, domain-general computation, or whether functions reside in domain-specific subdivisions. We scanned subjects with fMRI during five tasks known to activate the TPJ, probing social, attentional, and memory functions, and used data-driven parcellation (independent component analysis) to isolate task-related functional processes in the bilateral TPJ. We found that one dorsal component in the right TPJ, which was connected with the frontoparietal control network, was activated in all of the tasks. Other TPJ subregions were specific for attentional reorienting, oddball target detection, or social attribution of belief. The TPJ components that participated in attentional reorienting and oddball target detection appeared spatially separated, but both were connected with the ventral attention network. The TPJ component that participated in the theory-of-mind task was part of the default-mode network. Further, we found that the BOLD response in the domain-general dorsal component had a longer latency than responses in the domain-specific components, suggesting an involvement in distinct, perhaps postperceptual, computations. These findings suggest that the TPJ performs both domain-general and domain-specific computations that reside within spatially distinct functional components. PMID:27280153
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.
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.
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.
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.
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
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.
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
Recollection of episodic memory within the medial temporal lobe: behavioural dissociations from other types of memory.

PubMed

Easton, Alexander; Eacott, Madeline J

2010-12-31

In recent years there has been significant debate about whether there is a single medial temporal lobe memory system or dissociable systems for episodic and other types of declarative memory. In addition there has been a similar debate over the dissociability of recollection and familiarity based processes in recognition memory. Here we present evidence from recent work using episodic memory tasks in animals that allows us to explore these issues in more depth. We review studies that demonstrate triple dissociations within the medial temporal lobe, with only the hippocampal system being necessary for episodic memory. Similarly we review behavioural evidence for a dissociation in a task of episodic memory in rats where animals with lesions of the fornix are only impaired at recollection of the episodic memory, not recognition within the same trial. This work, then, supports recent models of dissociable neural systems within the medial temporal lobe but also raises questions for future investigation about the interactions of these medial temporal lobe memory systems with other structures. Copyright © 2009 Elsevier B.V. All rights reserved.
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.
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.

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.
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.
The Episodic Nature of Episodic-Like Memories

ERIC Educational Resources Information Center

Easton, Alexander; Webster, Lisa A. D.; Eacott, Madeline J.

2012-01-01

Studying episodic memory in nonhuman animals has proved difficult because definitions in humans require conscious recollection. Here, we assessed humans' experience of episodic-like recognition memory tasks that have been used with animals. It was found that tasks using contextual information to discriminate events could only be accurately…
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.
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.
Sleep Benefits in Parallel Implicit and Explicit Measures of Episodic Memory

ERIC Educational Resources Information Center

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…
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.
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.
How does intentionality of encoding affect memory for episodic information?

PubMed

Craig, Michael; Butterworth, Karla; Nilsson, Jonna; Hamilton, Colin J; Gallagher, Peter; Smulders, Tom V

2016-11-01

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. © 2016 Craig et al.; Published by Cold Spring Harbor Laboratory Press.
Physical Activity Is Positively Associated with Episodic Memory in Aging

PubMed Central

Hayes, Scott M.; Alosco, Michael L.; Hayes, Jasmeet P.; Cadden, Margaret; Peterson, Kristina M.; Allsup, Kelly; Forman, Daniel E.; Sperling, Reisa A.; Verfaellie, Mieke

2016-01-01

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. PMID:26581790
Temporal-contextual processing in working memory: evidence from delayed cued recall and delayed free recall tests.

PubMed

Loaiza, Vanessa M; McCabe, David P

2012-02-01

Three experiments are reported that addressed the nature of processing in working memory by investigating patterns of delayed cued recall and free recall of items initially studied during complex and simple span tasks. In Experiment 1, items initially studied during a complex span task (i.e., operation span) were more likely to be recalled after a delay in response to temporal-contextual cues, relative to items from subspan and supraspan list lengths in a simple span task (i.e., word span). In Experiment 2, items initially studied during operation span were more likely to be recalled from neighboring serial positions during delayed free recall than were items studied during word span trials. Experiment 3 demonstrated that the number of attentional refreshing opportunities strongly predicts episodic memory performance, regardless of whether the information is presented in a spaced or massed format in a modified operation span task. The results indicate that the content-context bindings created during complex span trials reflect attentional refreshing opportunities that are used to maintain items in working memory.
Interference Impacts Working Memory in Mild Cognitive Impairment

PubMed Central

Aurtenetxe, Sara; García-Pacios, Javier; del Río, David; López, María E.; Pineda-Pardo, José A.; Marcos, Alberto; Delgado Losada, Maria L.; López-Frutos, José M.; Maestú, Fernando

2016-01-01

Mild cognitive impairment (MCI) is considered a transitional stage between healthy aging and dementia, specifically Alzheimer's disease (AD). The most common cognitive impairment of MCI includes episodic memory loss and difficulties in working memory (WM). Interference can deplete WM, and an optimal WM performance requires an effective control of attentional resources between the memoranda and the incoming stimuli. Difficulties in handling interference lead to forgetting. However, the interplay between interference and WM in MCI is not well-understood and needs further investigation. The current study investigated the effect of interference during a WM task in 20 MCIs and 20 healthy elder volunteers. Participants performed a delayed match-to-sample paradigm which consisted in two interference conditions, distraction and interruption, and one control condition without any interference. Results evidenced a disproportionate impact of interference on the WM performance of MCIs, mainly in the presence of interruption. These findings demonstrate that interference, and more precisely interruption, is an important proxy for memory-related deficits in MCI. Thus, the current findings reveal novel evidence regarding the causes of WM forgetting in MCI patients, associated with difficulties in the mechanisms of attentional control. PMID:27790082
The Structure of Working Memory in Young Children and Its Relation to Intelligence

PubMed Central

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

2016-01-01

This study investigated the structure of working memory in young school-age children by testing the fit of three competing theoretical models using a wide variety of tasks. The best fitting models were then used to assess the relationship between working memory and nonverbal measures of fluid reasoning (Gf) and visual processing (Gv) intelligence. One hundred sixty-eight English-speaking 7–9 year olds with typical development, from three states, participated. Results showed that Cowan’s three-factor embedded processes model fit the data slightly better than Baddeley and Hitch’s (1974) three-factor model (specified according to Baddeley, 1986) and decisively better than Baddeley’s (2000) four-factor model that included an episodic buffer. The focus of attention factor in Cowan’s model was a significant predictor of Gf and Gv. The results suggest that the focus of attention, rather than storage, drives the relationship between working memory, Gf, and Gv in young school-age children. Our results do not rule out the Baddeley and Hitch model, but they place constraints on both it and Cowan’s model. A common attentional component is needed for feature binding, running digit span, and visual short-term memory tasks; phonological storage is separate, as is a component of central executive processing involved in task manipulation. The results contribute to a zeitgeist in which working memory models are coming together on common ground (cf. Cowan, Saults, & Blume, 2014; Hu, Allen, Baddeley, & Hitch, 2016). PMID:27990060
Does hormone therapy affect attention and memory in sleep-deprived women?

PubMed

Alhola, P; Kylmälä, M; Urrila, A Sofia; Karakorpi, M; Portin, R; Kalleinen, N; Polo-Kantola, P

2008-06-01

To evaluate whether hormone therapy (HT) modifies cognitive performance during sleep deprivation in postmenopausal women. Comparison was made with a group of young women. Participants included 26 postmenopausal women (age 58-72 years, 16 HT users, 10 non-users), 11 young women (age 20-26 years). They spent four consecutive nights in the sleep laboratory. Cognitive tests of attention, working memory, and verbal episodic memory were carried out after the baseline night, 25-h sleep deprivation, and recovery night. Sleep deprivation impaired performance in all groups. It was manifested either as delayed practice effect or deteriorated performance (p < 0.05). In simple reaction time and 10-choice reaction time, non-users and young maintained their performance, whereas HT users suffered a minor impairment (p < 0.01). In other measurements, there was no interaction of group and condition. In 10-choice reaction time and vigilance, postmenopausal women made fewer errors and omissions than the young (p < 0.05). For most tasks, all groups showed improvement after one recovery night. HT had a minor adverse effect on cognitive performance during sleep deprivation. Attention and memory deteriorated similarly in postmenopausal and young women, despite the lower initial performance level of postmenopausal women. One night of sleep ensured recovery in most tasks.
An intervention study on the effect of matcha tea, in drink and snack bar formats, on mood and cognitive performance.

PubMed

Dietz, Christina; Dekker, Matthijs; Piqueras-Fiszman, Betina

2017-09-01

Matcha tea is gaining popularity throughout the world in recent years and is frequently referred to as a mood-and-brain food. Previous research has demonstrated that three constituents present in matcha tea, l-theanine, epigallocatechin gallate (EGCG), and caffeine, affect mood and cognitive performance. However, to date there are no studies assessing the effect of matcha tea itself. The present study investigates these effects by means of a human intervention study administering matcha tea and a matcha containing product. Using a randomized, placebo-controlled, single-blind study, 23 consumers participated in four test sessions. In each session, participants consumed one of the four test products: matcha tea, matcha tea bar (each containing 4g matcha tea powder), placebo tea, or placebo bar. The assessment was performed at baseline and 60min post-treatment. The participants performed a set of cognitive tests assessing attention, information processing, working memory, and episodic memory. The mood state was measured by means of a Profile of Mood States (POMS). After consuming the matcha products compared to placebo versions, there were mainly significant improvements in tasks measuring basic attention abilities and psychomotor speed in response to stimuli over a defined period of time. In contrast to expectations, the effect was barely present in the other cognitive tasks. The POMS results revealed no significant changes in mood. The influence of the food matrix was demonstrated by the fact that on most cognitive performance measures the drink format outperformed the bar format, particularly in tasks measuring speed of spatial working memory and delayed picture recognition. This study suggests that matcha tea consumed in a realistic dose can induce slight effects on speed of attention and episodic secondary memory to a low degree. Further studies are required to elucidate the influences of the food matrix. Copyright © 2017 Elsevier Ltd. All rights reserved.
Episodic Memories and Their Relevance for Psychoactive Drug Use and Addiction

PubMed Central

Müller, Christian P.

2013-01-01

The majority of adult people in western societies regularly consume psychoactive drugs. While this consumption is integrated in everyday life activities and controlled in most consumers, it may escalate and result in drug addiction. Non-addicted drug use requires the systematic establishment of highly organized behaviors, such as drug-seeking and -taking. While a significant role for classical and instrumental learning processes is well established in drug use and abuse, declarative drug memories have largely been neglected in research. Episodic memories are an important part of the declarative memories. Here a role of episodic drug memories in the establishment of non-addicted drug use and its transition to addiction is suggested. In relation to psychoactive drug consumption, episodic drug memories are formed when a person prepares for consumption, when the drug is consumed and, most important, when acute effects, withdrawal, craving, and relapse are experienced. Episodic drug memories are one-trial memories with emotional components that can be much stronger than “normal” episodic memories. Their establishment coincides with drug-induced neuronal activation and plasticity. These memories may be highly extinction resistant and influence psychoactive drug consumption, in particular during initial establishment and at the transition to “drug instrumentalization.” In that, understanding how addictive drugs interact with episodic memory circuits in the brain may provide crucial information for how drug use and addiction are established. PMID:23734106

Episodic memories and their relevance for psychoactive drug use and addiction.

PubMed

Müller, Christian P

2013-01-01

The majority of adult people in western societies regularly consume psychoactive drugs. While this consumption is integrated in everyday life activities and controlled in most consumers, it may escalate and result in drug addiction. Non-addicted drug use requires the systematic establishment of highly organized behaviors, such as drug-seeking and -taking. While a significant role for classical and instrumental learning processes is well established in drug use and abuse, declarative drug memories have largely been neglected in research. Episodic memories are an important part of the declarative memories. Here a role of episodic drug memories in the establishment of non-addicted drug use and its transition to addiction is suggested. In relation to psychoactive drug consumption, episodic drug memories are formed when a person prepares for consumption, when the drug is consumed and, most important, when acute effects, withdrawal, craving, and relapse are experienced. Episodic drug memories are one-trial memories with emotional components that can be much stronger than "normal" episodic memories. Their establishment coincides with drug-induced neuronal activation and plasticity. These memories may be highly extinction resistant and influence psychoactive drug consumption, in particular during initial establishment and at the transition to "drug instrumentalization." In that, understanding how addictive drugs interact with episodic memory circuits in the brain may provide crucial information for how drug use and addiction are established.
Structural development of the hippocampus and episodic memory: developmental differences along the anterior/posterior axis.

PubMed

DeMaster, Dana; Pathman, Thanujeni; Lee, Joshua K; Ghetti, Simona

2014-11-01

The hippocampus is critically involved in episodic memory, yet relatively little is known about how the development of this structure contributes to the development of episodic memory during middle to late childhood. Previous research has inconsistently reported associations between hippocampal volume and episodic memory performance during this period. We argue that this inconsistency may be due to assessing the hippocampus as a whole, and propose to examine associations separately for subregions along the longitudinal axis of the hippocampus. In the present study, we examined age-related differences in volumes of the hippocampal head, body, and tail, and collected episodic memory measures in children ages 8-11 years and young adults (N = 62). We found that adults had a smaller right hippocampal head, larger hippocampal body bilaterally, and smaller right hippocampal tail compared with children. In adults, but not in children, better episodic memory performance was associated with smaller right hippocampal head and larger hippocampal body. In children, but not in adults, better episodic memory was associated with larger left hippocampal tail. Overall, the results suggest that protracted development of hippocampal subregions contribute to age-related differences in episodic memory. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Neuropsychological assessment of memory in child and adolescent first episode psychosis: cannabis and «the paradox effect».

PubMed

Moreno-Granados, Josefa María; Ferrín, Maite; Salcedo-Marín, Dolores M; Ruiz-Veguilla, Miguel

2014-01-01

The importance of neuropsychological functioning in First-Episode Psychosis (FEP) has led to the publication of a growing number of studies in this area of research. The present study pursued three goals: First, to examine verbal and visual memory in a sample of Child and Adolescent FEP, second, to evaluate the effect of other cognitive domains on verbal and visual memory, and finally, to examine the relationship between performance in this cognitive dimension and the use of cannabis at this age. A sample of 41 FEPs and 39 healthy subjects were evaluated. The variables assessed were verbal and visual memory, attention, working memory, processing speed, mental flexibility, verbal fluency, motor coordination, planning ability and intelligence. Our results found impairment of short and long-term recall of verbal memory, and short-term visual memory in early psychosis. They also found relationships between cognitive dimensions, such as visual memory and intelligence and motor coordination. Finally, a «paradoxical» effect was found in patients who used cannabis, as the FEP consumers performed the visual memory test better than those who had not used it. Patients showed impairment of short and long-term recall of verbal information and short-term visual reproduction. In the second place, motor coordination and intelligence influenced short-term visual memory in patients in the early stages of the illness. Third, use of cannabis in patients with FEP was associated with better performance in the test that evaluated the short-term visual memory, as measured by task completion time, that is, efficiency in performing the test. However, when measured by task execution accuracy, their visual memory was no better than the controls. Copyright © 2012 SEP y SEPB. Published by Elsevier España. All rights reserved.
Personal semantics: Is it distinct from episodic and semantic memory? An electrophysiological study of memory for autobiographical facts and repeated events in honor of Shlomo Bentin.

PubMed

Renoult, Louis; Tanguay, Annick; Beaudry, Myriam; Tavakoli, Paniz; Rabipour, Sheida; Campbell, Kenneth; Moscovitch, Morris; Levine, Brian; Davidson, Patrick S R

2016-03-01

Declarative memory is thought to consist of two independent systems: episodic and semantic. Episodic memory represents personal and contextually unique events, while semantic memory represents culturally-shared, acontextual factual knowledge. Personal semantics refers to aspects of declarative memory that appear to fall somewhere in between the extremes of episodic and semantic. Examples include autobiographical knowledge and memories of repeated personal events. These two aspects of personal semantics have been studied little and rarely compared to both semantic and episodic memory. We recorded the event-related potentials (ERPs) of 27 healthy participants while they verified the veracity of sentences probing four types of questions: general (i.e., semantic) facts, autobiographical facts, repeated events, and unique (i.e., episodic) events. Behavioral results showed equivalent reaction times in all 4 conditions. True sentences were verified faster than false sentences, except for unique events for which no significant difference was observed. Electrophysiological results showed that the N400 (which is classically associated with retrieval from semantic memory) was maximal for general facts and the LPC (which is classically associated with retrieval from episodic memory) was maximal for unique events. For both ERP components, the two personal semantic conditions (i.e., autobiographical facts and repeated events) systematically differed from semantic memory. In addition, N400 amplitudes also differentiated autobiographical facts from unique events. Autobiographical facts and repeated events did not differ significantly from each other but their corresponding scalp distributions differed from those associated with general facts. Our results suggest that the neural correlates of personal semantics can be distinguished from those of semantic and episodic memory, and may provide clues as to how unique events are transformed to semantic memory. Copyright © 2015 Elsevier Ltd. All rights reserved.
Functional connectivity pattern during rest within the episodic memory network in association with episodic memory performance in bipolar disorder.

PubMed

Oertel-Knöchel, Viola; Reinke, Britta; Matura, Silke; Prvulovic, David; Linden, David E J; van de Ven, Vincent

2015-02-28

In this study, we sought to examine the intrinsic functional organization of the episodic memory network during rest in bipolar disorder (BD). The previous work suggests that deficits in intrinsic functional connectivity may account for impaired memory performance. We hypothesized that regions involved in episodic memory processing would reveal aberrant functional connectivity in patients with bipolar disorder. We examined 21 patients with BD and 21 healthy matched controls who underwent functional magnetic resonance imaging (fMRI) during a resting condition. We did a seed-based functional connectivity analysis (SBA), using the regions of the episodic memory network that showed a significantly different activation pattern during task-related fMRI as seeds. The functional connectivity scores (FC) were further correlated with episodic memory task performance. Our results revealed decreased FC scores within frontal areas and between frontal and temporal/hippocampal/limbic regions in BD patients in comparison with controls. We observed higher FC in BD patients compared with controls between frontal and limbic regions. The decrease in fronto-frontal functional connectivity in BD patients showed a significant positive association with episodic memory performance. The association between task-independent dysfunctional frontal-limbic FC and episodic memory performance may be relevant for current pathophysiological models of the disease. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
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.
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.
Memory loss in Alzheimer's disease: implications for development of therapeutics

PubMed Central

Gold, Carl A; Budson, Andrew E

2009-01-01

Alzheimer's disease (AD) is a progressive neurodegenerative disease marked by a constellation of cognitive disturbances, the earliest and most prominent being impaired episodic memory. Episodic memory refers to the memory system that allows an individual to consciously retrieve a previously experienced item or episode of life. Many recent studies have focused on characterizing how AD pathology impacts particular aspects of episodic memory and underlying mental and neural processes. This review summarizes the findings of those studies and discusses the effects of current and promising treatments for AD on episodic memory. The goal of this review is to raise awareness of the strides that cognitive neuroscientists have made in understanding intact and dysfunctional memory. Knowledge of the specific memorial processes that are impaired in AD may be of great value to basic scientists developing novel therapies and to clinical researchers assessing the efficacy of those therapies. PMID:19086882
Episodic memory deficits slow down the dynamics of cognitive procedural learning in normal ageing

PubMed Central

Beaunieux, Hélène; Hubert, Valérie; Pitel, Anne Lise; Desgranges, Béatrice; Eustache, Francis

2009-01-01

Cognitive procedural learning is characterized by three phases, each involving distinct processes. Considering the implication of the episodic memory in the first cognitive stage, the impairment of this memory system might be responsible for a slowing down of the cognitive procedural learning dynamics in the course of aging. Performances of massed cognitive procedural learning were evaluated in older and younger participants using the Tower of Toronto task. Nonverbal intelligence and psychomotor abilities were used to analyze procedural dynamics, while episodic memory and working memory were assessed to measure their respective contributions to learning strategies. This experiment showed that older participants did not spontaneously invoke episodic memory and presented a slowdown in the cognitive procedural learning associated with a late involvement of working memory. These findings suggest that the slowdown in the cognitive procedural learning may be linked with the implementation of different learning strategies less involving episodic memory in older subjects. PMID:18654928
Variability in memory performance in aged healthy individuals: an fMRI study.

PubMed

Grön, Georg; Bittner, Daniel; Schmitz, Bernd; Wunderlich, Arthur P; Tomczak, Reinhard; Riepe, Matthias W

2003-01-01

Episodic memory performance varies in older subjects but underlying biological correlates remain as yet ambiguous. We investigated episodic memory in healthy older individuals (n=24; mean age: 64.4+/-6.7 years) without subjective memory complaints or objective cognitive impairment. Episodic memory was assessed with repetitive learning and recall of abstract geometric patterns during fMRI. Group analysis of brain activity during initial learning and maximum recall revealed hippocampal activation. Correlation analysis of brain activation and task performance demonstrated significant hippocampal activity during initial learning and maximum recall in a success-dependent manner. Neither age nor gray matter densities correlated with hippocampal activation. Functional imaging of episodic memory thus permits to detect objectively variability in hippocampal recruitment in healthy aged individuals without subjective memory complaints. Correlation analysis of brain activation and performance during an episodic memory task may be used to determine and follow-up hippocampal malfunction in a very sensitive manner.
Noninvasive stimulation of prefrontal cortex strengthens existing episodic memories and reduces forgetting in the elderly

PubMed Central

Sandrini, Marco; Brambilla, Michela; Manenti, Rosa; Rosini, Sandra; Cohen, Leonardo G.; Cotelli, Maria

2014-01-01

Memory consolidation is a dynamic process. Reactivation of consolidated memories by a reminder triggers reconsolidation, a time-limited period during which existing memories can be modified (i.e., weakened or strengthened). Episodic memory refers to our ability to recall specific past events about what happened, including where and when. Difficulties in this form of long-term memory commonly occur in healthy aging. Because episodic memory is critical for daily life functioning, the development of effective interventions to reduce memory loss in elderly individuals is of great importance. Previous studies in young adults showed that the dorsolateral prefrontal cortex (DLPFC) plays a causal role in strengthening of verbal episodic memories through reconsolidation. The aim of the present study was to explore the extent to which facilitatory transcranial direct current stimulation (anodal tDCS) over the left DLPFC would strengthen existing episodic memories through reconsolidation in elderly individuals. On Day 1, older adults learned a list of 20 words. On Day 2 (24 h later), they received a reminder or not, and after 10 min tDCS was applied over the left DLPFC. Memory recall was tested on Day 3 (48 h later) and Day 30 (1 month later). Surprisingly, anodal tDCS over the left DLPFC (i.e., with or without the reminder) strengthened existing verbal episodic memories and reduced forgetting compared to sham stimulation. These results provide a framework for testing the hypothesis that facilitatory tDCS of left DLPFC might strengthen existing episodic memories and reduce memory loss in older adults with amnestic mild cognitive impairment. PMID:25368577
Older adults get episodic memory boosting from noninvasive stimulation of prefrontal cortex during learning.

PubMed

Sandrini, Marco; Manenti, Rosa; Brambilla, Michela; Cobelli, Chiara; Cohen, Leonardo G; Cotelli, Maria

2016-03-01

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. Copyright © 2016 Elsevier Inc. All rights reserved.
Cognitive Processes Supporting Episodic Memory Formation in Childhood: The Role of Source Memory, Binding, and Executive Functioning

ERIC Educational Resources Information Center

Raj, Vinaya; Bell, Martha Ann

2010-01-01

Episodic memories contain various forms of contextual detail (e.g., perceptual, emotional, cognitive details) that need to become integrated. Each of these contextual features can be used to attribute a memory episode to its source, or origin of information. Memory for source information is one critical component in the formation of episodic…
Everyday episodic memory in amnestic mild cognitive impairment: a preliminary investigation

PubMed Central

2011-01-01

Background Decline in episodic memory is one of the hallmark features of Alzheimer's disease (AD) and is also a defining feature of amnestic Mild Cognitive Impairment (MCI), which is posited as a potential prodrome of AD. While deficits in episodic memory are well documented in MCI, the nature of this impairment remains relatively under-researched, particularly for those domains with direct relevance and meaning for the patient's daily life. In order to fully explore the impact of disruption to the episodic memory system on everyday memory in MCI, we examined participants' episodic memory capacity using a battery of experimental tasks with real-world relevance. We investigated episodic acquisition and delayed recall (story-memory), associative memory (face-name pairings), spatial memory (route learning and recall), and memory for everyday mundane events in 16 amnestic MCI and 18 control participants. Furthermore, we followed MCI participants longitudinally to gain preliminary evidence regarding the possible predictive efficacy of these real-world episodic memory tasks for subsequent conversion to AD. Results The most discriminating tests at baseline were measures of acquisition, delayed recall, and associative memory, followed by everyday memory, and spatial memory tasks, with MCI patients scoring significantly lower than controls. At follow-up (mean time elapsed: 22.4 months), 6 MCI cases had progressed to clinically probable AD. Exploratory logistic regression analyses revealed that delayed associative memory performance at baseline was a potential predictor of subsequent conversion to AD. Conclusions As a preliminary study, our findings suggest that simple associative memory paradigms with real-world relevance represent an important line of enquiry in future longitudinal studies charting MCI progression over time. PMID:21816065
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.
Sex differences in cognitive functioning in at-risk mental state for psychosis, first episode psychosis and healthy control subjects.

PubMed

Ittig, S; Studerus, E; Papmeyer, M; Uttinger, M; Koranyi, S; Ramyead, A; Riecher-Rössler, A

2015-02-01

Several sex differences in schizophrenia have been reported including differences in cognitive functioning. Studies with schizophrenia patients and healthy controls (HC) indicate that the sex advantage for women in verbal domains is also present in schizophrenia patients. However, findings have been inconsistent. No study focused on sex-related cognitive performance differences in at-risk mental state for psychosis (ARMS) individuals yet. Thus, the aim of the present study was to investigate sex differences in cognitive functioning in ARMS, first episode psychosis (FEP) and HC subjects. We expected a better verbal learning and memory performance of women in all groups. The neuropsychological data analysed in this study were collected within the prospective Früherkennung von Psychosen (FePsy) study. In total, 118 ARMS, 88 FEP individuals and 86 HC completed a cognitive test battery covering the domains of executive functions, attention, working memory, verbal learning and memory, IQ and speed of processing. Women performed better in verbal learning and memory regardless of diagnostic group. By contrast, men as compared to women showed a shorter reaction time during the working memory task across all groups. The results provide evidence that women generally perform better in verbal learning and memory, independent of diagnostic group (ARMS, FEP, HC). The finding of a shorter reaction time for men in the working memory task could indicate that men have a superior working memory performance since they responded faster during the target trials, while maintaining a comparable overall working memory performance level. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Memory systems in schizophrenia: Modularity is preserved but deficits are generalized.

PubMed

Haut, Kristen M; Karlsgodt, Katherine H; Bilder, Robert M; Congdon, Eliza; Freimer, Nelson B; London, Edythe D; Sabb, Fred W; Ventura, Joseph; Cannon, Tyrone D

2015-10-01

Schizophrenia patients exhibit impaired working and episodic memory, but this may represent generalized impairment across memory modalities or performance deficits restricted to particular memory systems in subgroups of patients. Furthermore, it is unclear whether deficits are unique from those associated with other disorders. Healthy controls (n=1101) and patients with schizophrenia (n=58), bipolar disorder (n=49) and attention-deficit-hyperactivity-disorder (n=46) performed 18 tasks addressing primarily verbal and spatial episodic and working memory. Effect sizes for group contrasts were compared across tasks and the consistency of subjects' distributional positions across memory domains was measured. Schizophrenia patients performed poorly relative to the other groups on every test. While low to moderate correlation was found between memory domains (r=.320), supporting modularity of these systems, there was limited agreement between measures regarding each individual's task performance (ICC=.292) and in identifying those individuals falling into the lowest quintile (kappa=0.259). A general ability factor accounted for nearly all of the group differences in performance and agreement across measures in classifying low performers. Pathophysiological processes involved in schizophrenia appear to act primarily on general abilities required in all tasks rather than on specific abilities within different memory domains and modalities. These effects represent a general shift in the overall distribution of general ability (i.e., each case functioning at a lower level than they would have if not for the illness), rather than presence of a generally low-performing subgroup of patients. There is little evidence that memory impairments in schizophrenia are shared with bipolar disorder and ADHD. Copyright © 2015 Elsevier B.V. All rights reserved.
Memory systems in schizophrenia: Modularity is preserved but deficits are generalized

PubMed Central

Haut, Kristen M.; Karlsgodt, Katherine H.; Bilder, Robert M.; Congdon, Eliza; Freimer, Nelson; London, Edythe D.; Sabb, Fred W.; Ventura, Joseph; Cannon, Tyrone D.

2015-01-01

Objective Schizophrenia patients exhibit impaired working and episodic memory, but this may represent generalized impairment across memory modalities or performance deficits restricted to particular memory systems in subgroups of patients. Furthermore, it is unclear whether deficits are unique from those associated with other disorders. Method Healthy controls (n=1101) and patients with schizophrenia (n=58), bipolar disorder (n=49) and attention-deficit-hyperactivity-disorder (n=46) performed 18 tasks addressing primarily verbal and spatial episodic and working memory. Effect sizes for group contrasts were compared across tasks and the consistency of subjects’ distributional positions across memory domains was measured. Results Schizophrenia patients performed poorly relative to the other groups on every test. While low to moderate correlation was found between memory domains (r=.320), supporting modularity of these systems, there was limited agreement between measures regarding each individual’s task performance (ICC=.292) and in identifying those individuals falling into the lowest quintile (kappa=0.259). A general ability factor accounted for nearly all of the group differences in performance and agreement across measures in classifying low performers. Conclusions Pathophysiological processes involved in schizophrenia appear to act primarily on general abilities required in all tasks rather than on specific abilities within different memory domains and modalities. These effects represent a general shift in the overall distribution of general ability (i.e., each case functioning at a lower level than they would have if not for the illness), rather than presence of a generally low-performing subgroup of patients. There is little evidence that memory impairments in schizophrenia are shared with bipolar disorder and ADHD. PMID:26299707
"Being there" and remembering it: Presence improves memory encoding.

PubMed

Makowski, Dominique; Sperduti, Marco; Nicolas, Serge; Piolino, Pascale

2017-08-01

Few studies have investigated the link between episodic memory and presence: the feeling of "being there" and reacting to a stimulus as if it were real. We collected data from 244 participants after they had watched the movie Avengers: Age of Ultron. They answered questions about factual (details of the movie) and temporal memory (order of the scenes) about the movie, as well as their emotion experience and their sense of presence during the projection. Both higher emotion experience and sense of presence were related to better factual memory, but not to temporal order memory. Crucially, the link between emotion and factual memory was mediated by the sense of presence. We interpreted the role of presence as an external absorption of the attentional focus toward the stimulus, thus enhancing memory encoding. Our findings could shed light on the cognitive processes underlying memory impairments in psychiatric conditions characterized by an altered sense of reality. Copyright © 2017 Elsevier Inc. All rights reserved.
The role of memory for visual search in scenes

PubMed Central

Võ, Melissa Le-Hoa; Wolfe, Jeremy M.

2014-01-01

Many daily activities involve looking for something. The ease with which these searches are performed often allows one to forget that searching represents complex interactions between visual attention and memory. While a clear understanding exists of how search efficiency will be influenced by visual features of targets and their surrounding distractors or by the number of items in the display, the role of memory in search is less well understood. Contextual cueing studies have shown that implicit memory for repeated item configurations can facilitate search in artificial displays. When searching more naturalistic environments, other forms of memory come into play. For instance, semantic memory provides useful information about which objects are typically found where within a scene, and episodic scene memory provides information about where a particular object was seen the last time a particular scene was viewed. In this paper, we will review work on these topics, with special emphasis on the role of memory in guiding search in organized, real-world scenes. PMID:25684693

The role of memory for visual search in scenes.

PubMed

Le-Hoa Võ, Melissa; Wolfe, Jeremy M

2015-03-01

Many daily activities involve looking for something. The ease with which these searches are performed often allows one to forget that searching represents complex interactions between visual attention and memory. Although a clear understanding exists of how search efficiency will be influenced by visual features of targets and their surrounding distractors or by the number of items in the display, the role of memory in search is less well understood. Contextual cueing studies have shown that implicit memory for repeated item configurations can facilitate search in artificial displays. When searching more naturalistic environments, other forms of memory come into play. For instance, semantic memory provides useful information about which objects are typically found where within a scene, and episodic scene memory provides information about where a particular object was seen the last time a particular scene was viewed. In this paper, we will review work on these topics, with special emphasis on the role of memory in guiding search in organized, real-world scenes. © 2015 New York Academy of Sciences.
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.
A Role for Memory in Prospective Timing informs Timing in Prospective Memory

PubMed Central

Waldum, Emily R; Sahakyan, Lili

2014-01-01

Time-based prospective memory (TBPM) tasks require the estimation of time in passing – known as prospective timing. Prospective timing is said to depend on an attentionally-driven internal clock mechanism, and is thought to be unaffected by memory for interval information (for reviews see, Block, Hancock, & Zakay, 2010; Block & Zakay, 1997). A prospective timing task that required a verbal estimate following the entire interval (Experiment 1) and a TBPM task that required production of a target response during the interval (Experiment 2) were used to test an alternative view that episodic memory does influence prospective timing. In both experiments, participants performed an ongoing lexical decision task of fixed duration while a varying number of songs were played in the background. Experiment 1 results revealed that verbal time estimates became longer the more songs participants remembered from the interval, suggesting that memory for interval information influences prospective time estimates. In Experiment 2, participants who were asked to perform the TBPM task without the aid of an external clock made their target responses earlier as the number of songs increased, indicating that prospective estimates of elapsed time increased as more songs were experienced. For participants who had access to a clock, changes in clock-checking coincided with the occurrence of song boundaries, indicating that participants used both song information and clock information to estimate time. Finally, ongoing task performance and verbal reports in both experiments further substantiate a role for episodic memory in prospective timing. PMID:22984950
How Limited Systematicity Emerges: A Computational Cognitive Neuroscience Approach (Author’s Manuscript)

DTIC Science & Technology

2014-09-01

not losing track of the original facts of the situation. However, hippocampal episodic memory also has limitations – it operates one memory at a...ability to strategically control the use of episodic memory . Specific areas of PFC are implicated as these episodic control structures, including...certainly start by encoding the problem into hippocampal episodic memory , so they can retrieve it when interference overtakes the system and they
Memory of occasional events in rats: individual episodic memory profiles, flexibility, and neural substrate.

PubMed

Veyrac, Alexandra; Allerborn, Marina; Gros, Alexandra; Michon, Frederic; Raguet, Louise; Kenney, Jana; Godinot, Florette; Thevenet, Marc; Garcia, Samuel; Messaoudi, Belkacem; Laroche, Serge; Ravel, Nadine

2015-05-13

In search for the mechanisms underlying complex forms of human memory, such as episodic recollection, a primary challenge is to develop adequate animal models amenable to neurobiological investigation. Here, we proposed a novel framework and paradigm that provides means to quantitatively evaluate the ability of rats to form and recollect a combined knowledge of what happened, where it happened, and when or in which context it happened (referred to as episodic-like memory) after a few specific episodes in situations as close as possible to a paradigm we recently developed to study episodic memory in humans. In this task, rats have to remember two odor-drink associations (what happened) encountered in distinct locations (where it happened) within two different multisensory enriched environments (in which context/occasion it happened), each characterized by a particular combination of odors and places. By analyzing licking behavior on each drinking port, we characterized quantitatively individual recollection profiles and showed that rats are able to incidentally form and recollect an accurate, long-term integrated episodic-like memory that can last ≥ 24 d after limited exposure to the episodes. Placing rats in a contextually challenging recollection situation at recall reveals the ability for flexible use of episodic memory as described in humans. We further report that reversible inactivation of the dorsal hippocampus during recall disrupts the animal's capacity to recollect the complete episodic memory. Cellular imaging of c-Fos and Zif268 brain activation reveals that episodic memory recollection recruits a specific, distributed network of hippocampal-prefrontal cortex structures that correlates with the accuracy of the integrated recollection performance. Copyright © 2015 the authors 0270-6474/15/337575-12$15.00/0.
Preservation of episodic memory in semantic dementia: The importance of regions beyond the medial temporal lobes.

PubMed

Irish, Muireann; Bunk, Steffie; Tu, Sicong; Kamminga, Jody; Hodges, John R; Hornberger, Michael; Piguet, Olivier

2016-01-29

Episodic memory impairment represents one of the hallmark clinical features of patients with Alzheimer's disease (AD) attributable to the degeneration of medial temporal and parietal regions of the brain. In contrast, a somewhat paradoxical profile of relatively intact episodic memory, particularly for non-verbal material, is observed in semantic dementia (SD), despite marked atrophy of the hippocampus. This retrospective study investigated the neural substrates of episodic memory retrieval in 20 patients with a diagnosis of SD and 21 disease-matched cases of AD and compared their performance to that of 35 age- and education-matched healthy older Controls. Participants completed the Rey Complex Figure and the memory subscale of the Addenbrooke's Cognitive Examination-Revised as indices of visual and verbal episodic recall, respectively. Relative to Controls, AD patients showed compromised memory performance on both visual and verbal memory tasks. In contrast, memory deficits in SD were modality-specific occurring exclusively on the verbal task. Controlling for semantic processing ameliorated these deficits in SD, while memory impairments persisted in AD. Voxel-based morphometry analyses revealed significant overlap in the neural correlates of verbal episodic memory in AD and SD with predominantly anteromedial regions, including the bilateral hippocampus, strongly implicated. Controlling for semantic processing negated this effect in SD, however, a distributed network of frontal, medial temporal, and parietal regions was implicated in AD. Our study corroborates the view that episodic memory deficits in SD arise very largely as a consequence of the conceptual loading of traditional tasks. We propose that the functional integrity of frontal and parietal regions enables new learning to occur in SD in the face of significant hippocampal and anteromedial temporal lobe pathology, underscoring the inherent complexity of the episodic memory circuitry. Copyright © 2015 Elsevier Ltd. All rights reserved.
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
Episodic representations support early semantic learning: evidence from midazolam induced amnesia.

PubMed

Merritt, Paul; Hirshman, Elliot; Zamani, Shane; Hsu, John; Berrigan, Michael

2006-07-01

Current controversy exists regarding the role of episodic representations in the formation of long-term semantic memories. Using the drug midazolam to induce temporary amnesia we tested participants' memories for newly learned facts in a semantic cue condition or an episodic and semantic cue condition. Following midazolam administration, memory performance was superior in the episodic and semantic condition, suggesting early semantic learning is supported by episodic representations.
Role of slow oscillatory activity and slow wave sleep in consolidation of episodic-like memory in rats.

PubMed

Oyanedel, Carlos N; Binder, Sonja; Kelemen, Eduard; Petersen, Kimberley; Born, Jan; Inostroza, Marion

2014-12-15

Our previous experiments showed that sleep in rats enhances consolidation of hippocampus dependent episodic-like memory, i.e. the ability to remember an event bound into specific spatio-temporal context. Here we tested the hypothesis that this enhancing effect of sleep is linked to the occurrence of slow oscillatory and spindle activity during slow wave sleep (SWS). Rats were tested on an episodic-like memory task and on three additional tasks covering separately the where (object place recognition), when (temporal memory), and what (novel object recognition) components of episodic memory. In each task, the sample phase (encoding) was followed by an 80-min retention interval that covered either a period of regular morning sleep or sleep deprivation. Memory during retrieval was tested using preferential exploration of novelty vs. familiarity. Consistent with previous findings, the rats which had slept during the retention interval showed significantly stronger episodic-like memory and spatial memory, and a trend of improved temporal memory (although not significant). Object recognition memory was similarly retained across sleep and sleep deprivation retention intervals. Recall of episodic-like memory was associated with increased slow oscillatory activity (0.85-2.0Hz) during SWS in the retention interval. Spatial memory was associated with increased proportions of SWS. Against our hypothesis, a relationship between spindle activity and episodic-like memory performance was not detected, but spindle activity was associated with object recognition memory. The results provide support for the role of SWS and slow oscillatory activity in consolidating hippocampus-dependent memory, the role of spindles in this process needs to be further examined. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.
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.
Thinking about the future can cause forgetting of the past.

PubMed

Ditta, Annie S; Storm, Benjamin C

2016-01-01

People are able to imagine events in the future that have not yet happened, an ability referred to as episodic future thinking. There is now compelling evidence that episodic future thinking is accomplished via processes similar to those that underlie episodic retrieval. Drawing upon work on retrieval-induced forgetting, which has shown that retrieving some items in memory can cause the forgetting of other items in memory, we show that engaging in episodic future thinking can cause related autobiographical memories (Experiments 1-3) and episodic event descriptions (Experiments 3-4) to become less recallable in the future than they would have been otherwise. This finding suggests that episodic future thinking can serve as a memory modifier by changing the extent to which memories from our past can be subsequently retrieved.
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.
Episodic and Semantic Memory: Implications for the Role of Emotion in Advertising.

ERIC Educational Resources Information Center

Thorson, Esther

In an examination of the way people store and retrieve information from advertising, this paper draws a distinction between "semantic" memory, which stores general knowledge about the world, and "episodic" memory, which stores information about specific events. It then argues that episodic memory plays a more significant role…
Developmental roots of episodic memory.

PubMed

Nelson, Katherine

2018-01-01

Two arguments imply that Mahr & Csibra's (M&C's) functional theory is insufficient as an explanation of episodic memory: (1) The developmental course supports a different social cultural division of episodic and semantic memory, and (2) the existence of long-term autobiographical memory is not explained in the functional theory but can be seen in a broader cultural framework.
Intrusions in Episodic Memory: Reconsolidation or Interference?

ERIC Educational Resources Information Center

Klingmüller, Angela; Caplan, Jeremy B.; Sommer, Tobias

2017-01-01

It would be profoundly important if reconsolidation research in animals and other memory domains generalized to human episodic memory. A 3-d-list-discrimination procedure, based on free recall of objects, with a contextual reminder cue (the testing room), has been thought to demonstrate reconsolidation of human episodic memory (as noted in a…
[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.
A unique memory process modulated by emotion underpins successful odor recognition and episodic retrieval in humans

PubMed Central

Saive, Anne-Lise; Royet, Jean-Pierre; Ravel, Nadine; Thévenet, Marc; Garcia, Samuel; Plailly, Jane

2014-01-01

We behaviorally explore the link between olfaction, emotion and memory by testing the hypothesis that the emotion carried by odors facilitates the memory of specific unique events. To investigate this idea, we used a novel behavioral approach inspired by a paradigm developed by our team to study episodic memory in a controlled and as ecological as possible way in humans. The participants freely explored three unique and rich laboratory episodes; each episode consisted of three unfamiliar odors (What) positioned at three specific locations (Where) within a visual context (Which context). During the retrieval test, which occurred 24–72 h after the encoding, odors were used to trigger the retrieval of the complex episodes. The participants were proficient in recognizing the target odors among distractors and retrieving the visuospatial context in which they were encountered. The episodic nature of the task generated high and stable memory performances, which were accompanied by faster responses and slower and deeper breathing. Successful odor recognition and episodic memory were not related to differences in odor investigation at encoding. However, memory performances were influenced by the emotional content of the odors, regardless of odor valence, with both pleasant and unpleasant odors generating higher recognition and episodic retrieval than neutral odors. Finally, the present study also suggested that when the binding between the odors and the spatio-contextual features of the episode was successful, the odor recognition and the episodic retrieval collapsed into a unique memory process that began as soon as the participants smelled the odors. PMID:24936176
Apolipoprotein E (APOE) ε4 and episodic memory decline in Alzheimer's disease: A review.

PubMed

El Haj, Mohamad; Antoine, Pascal; Amouyel, Philippe; Lambert, Jean-Charles; Pasquier, Florence; Kapogiannis, Dimitrios

2016-05-01

A growing body of research has examined the relationship between episodic memory decline, the cognitive hallmark of Alzheimer's disease (AD), and the presence of Apolipoprotein E ε4 (APOE ε4) allele, a major genetic risk factor for the disease. Our review attempts to summarize and critically evaluate this literature. We performed a systematic search for studies assessing episodic memory in AD patients who were genotyped for APOE ε4 and identified fourteen papers. Although most of these papers reported significant relationships between APOE ε4 and episodic memory decline in AD, some papers did not confirm this relationship. Our review links this controversy to the conflicting literature about the effects of APOE ε4 on general cognitive functioning in AD. We identify several shortcoming and limitations of the research on the relationship between APOE ε4 and episodic memory in AD, such as small sample sizes, non-representative populations, lack of comparison of early-onset vs. late-onset disease, and lack of comparison among different genotypes that include APOE ε4 (i.e., zero, one, or two ε4 alleles). Another major shortcoming of the reviewed literature was the lack of comprehensive evaluation of episodic memory decline, since episodic memory was solely evaluated with regard to encoding and retrieval, omitting evaluation of core episodic features that decline in AD, such as context recall (e.g., how, where, and when an episodic event has occurred) and subjective experience of remembering (e.g., reliving, emotion and feeling during episodic recollection). Future research taking these limitations into consideration could illuminate the nature of the relationship between APOE ε4 and episodic memory decline in AD. Copyright © 2016 Elsevier B.V. All rights reserved.
Using Virtual Reality to Characterize Episodic Memory Profiles in Amnestic Mild Cognitive Impairment and Alzheimer's Disease: Influence of Active and Passive Encoding

ERIC Educational Resources Information Center

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

2012-01-01

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,…
Comparative Cognition: Action Imitation Using Episodic Memory.

PubMed

Crystal, Jonathon D

2016-12-05

Humans encounter a myriad of actions or events and later recall some of these events using episodic memory. New research suggests that dogs can imitate recently encountered actions using episodic memory. Copyright Â© 2016 Elsevier Ltd. All rights reserved.

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.
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
The role of speed versus working memory in predicting learning new information in multiple sclerosis.

PubMed

Chiaravalloti, Nancy D; Stojanovic-Radic, Jelena; DeLuca, John

2013-01-01

The most common cognitive impairments in multiple sclerosis (MS) have been documented in specific domains, including new learning and memory, working memory, and information processing speed. However, little attempt has been made to increase our understanding of their relationship to one another. While recent studies have shown that processing speed impacts new learning and memory abilities in MS, the role of working memory in this relationship has received less attention. The present study examines the relative contribution of impaired working memory versus processing speed in new learning and memory functions in MS. Participants consisted of 51 individuals with clinically definite MS. Participants completed two measures of processing speed, two measures of working memory, and two measures of episodic memory. Data were analyzed via correlational and multiple regression analysis. Results indicate that the variance in new learning abilities in this sample was primarily associated with processing speed, with working memory exerting much less of an influence. Results are discussed in terms of the role of cognitive rehabilitation of new learning and memory abilities in persons with MS.
The Episodicity of Verbal Reports of Personally Significant Autobiographical Memories: Vividness Correlates with Narrative Text Quality More than with Detailedness or Memory Specificity

PubMed Central

Habermas, Tilmann; Diel, Verena

2013-01-01

How can we tell from a memory report whether a memory is episodic or not? Vividness is required by many definitions, whereas detailedness, memory specificity, and narrative text type are competing definitions of episodicity used in research. We explored their correlations with vividness in personally significant autobiographical memories to provide evidence to support their relative claim to define episodic memories. In addition, we explored differences between different memory types and text types as well as between memories with different valences. We asked a lifespan sample (N = 168) of 8-, 12-, 16-, 20-, 40-, and 65-year-olds of both genders (N = 27, 29, 27, 27, 28, 30) to provide brief oral life narratives. These were segmented into thematic memory units. Detailedness of person, place, and time did not correlate with each other or either vividness, memory specificity, or narrative text type. Narrative text type, in contrast, correlated both with vividness and memory specificity, suggesting narrative text type as a good criterion of episodicity. Emotionality turned out to be an even better predictor of vividness. Also, differences between narrative, chronicle, and argument text types and between specific versus more extended and atemporal memories were explored as well as differences between positive, negative, ambivalent, neutral, contamination, and redemption memory reports. It is concluded that temporal sequentiality is a central characteristic of episodic autobiographical memories. Furthermore, it is suggested that the textual quality of memory reports should be taken more seriously, and that evaluation and interpretation are inherent aspects of personally significant memories. PMID:23966918
Why do we remember? The communicative function of episodic memory

PubMed Central

Mahr, Johannes B.; Csibra, Gergely

2017-01-01

Short Abstract We propose a novel account of episodic memory function based on a conceptual and empirical analysis of its role in belief formation. We provide a critique of the view that episodic memory serves future-directed imagination, and argue that the central features of this capacity can instead be explained by the role it plays in human communication. On this view, episodic memory allows us to communicatively support our interpretations of the past by gauging when we can assert epistemic authority. This capacity is ineliminable in justification of, and negotiations about, social commitments established by past interactions. Long Abstract Episodic memory has been analyzed in a number of different ways in both philosophy and psychology, and most controversy has centered on its self-referential, ‘autonoetic’ character. Here, we offer a comprehensive characterization of episodic memory in representational terms, and propose a novel functional account on this basis. We argue that episodic memory should be understood as a distinctive epistemic attitude taken towards an event simulation. On this view, episodic memory has a metarepresentational format and should not be equated with beliefs about the past. Instead, empirical findings suggest that the contents of human episodic memory are often constructed in the service of the explicit justification of such beliefs. Existing accounts of episodic memory function that have focused on explaining its constructive character through its role in ‘future-oriented mental time travel’ neither do justice to its capacity to ground veridical beliefs about the past nor to its representational format. We provide an account of the metarepresentational structure of episodic memory in terms of its role in communicative interaction. The generative nature of recollection allows us to represent and communicate the reasons for why we hold certain beliefs about the past. In this process, autonoesis corresponds to the capacity to determine when and how to assert epistemic authority in making claims about the past. A domain where such claims are indispensable are human social engagements. Such engagements commonly require the justification of entitlements and obligations, which is often possible only by explicit reference to specific past events. PMID:28100294
Functional brain imaging of episodic memory decline in ageing.

PubMed

Nyberg, L

2017-01-01

The episodic long-term memory system supports remembering of events. It is considered to be the most age-sensitive system, with an average onset of decline around 60 years of age. However, there is marked interindividual variability, such that some individuals show faster than average change and others show no or very little change. This variability may be related to the risk of developing dementia, with elevated risk for individuals with accelerated episodic memory decline. Brain imaging with functional magnetic resonance imaging (MRI) of blood oxygen level-dependent (BOLD) signalling or positron emission tomography (PET) has been used to reveal the brain bases of declining episodic memory in ageing. Several studies have demonstrated a link between age-related episodic memory decline and the hippocampus during active mnemonic processing, which is further supported by studies of hippocampal functional connectivity in the resting state. The hippocampus interacts with anterior and posterior neocortical regions to support episodic memory, and alterations in hippocampus-neocortex connectivity have been shown to contribute to impaired episodic memory. Multimodal MRI studies and more recently hybrid MRI/PET studies allow consideration of various factors that can influence the association between the hippocampal BOLD signal and memory performance. These include neurovascular factors, grey and white matter structural alterations, dopaminergic neurotransmission, amyloid-Β and glucose metabolism. Knowledge about the brain bases of episodic memory decline can guide interventions to strengthen memory in older adults, particularly in those with an elevated risk of developing dementia, with promising results for combinations of cognitive and physical stimulation. © 2016 The Association for the Publication of the Journal of Internal Medicine.
Sentence Verification, Sentence Recognition, and the Semantic-Episodic Distinction

ERIC Educational Resources Information Center

Shoben, Edward J.; And Others

1978-01-01

In an attempt to assess the validity of the distinction between episodic and semantic memory, this research examined the influence of two variables on sentence verification (presumably a semantic memory task) and sentence recognition (presumably an episodic memory task). ( Editor)
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
Study of metamemory in patients with chronic alcoholism using a feeling-of-knowing episodic memory task.

PubMed

Le Berre, Anne-Pascale; Pinon, Karine; Vabret, François; Pitel, Anne-Lise; Allain, Philippe; Eustache, Francis; Beaunieux, Hélène

2010-11-01

Alcoholism affects various cognitive processes, including components of memory. Metamemory, though of particular interest for patient treatment, has not yet been extensively investigated. A feeling-of-knowing (FOK) measure of metamemory was administered to 28 alcoholic patients and 28 healthy controls during an episodic memory task including the learning of 20 pairs of items, followed by a 20-minute delayed recall and a recognition task. Prior to recognition, participants rated their ability to recognize each nonrecalled word among 4 items. This episodic FOK measure served to compare predictions of future recognition performance and actual recognition performance. Furthermore, a subjective measure of metamemory, the Metamemory In Adulthood (MIA) questionnaire, was completed by patients and controls. This assessment of alcoholic patients' metamemory profile was accompanied by an evaluation of episodic memory and executive functioning. FOK results revealed deficits in accuracy, with the alcoholic patients providing overestimations. There were also links between FOK inaccuracy, executive decline, and episodic memory impairment in patients. MIA results showed that although alcoholics did display memory difficulties, they did not differ from controls on questions about memory capacity. Chronic alcoholism affects both episodic memory and metamemory for novel information. Patients were relatively unaware of their memory deficits and believed that their memory was as good as that of the healthy controls. The monitoring measure (FOK) and the subjective measure of metamemory (MIA) showed that patients with chronic alcoholism overestimated their memory capacities. Episodic memory deficit and executive dysfunction would explain metamemory decline in this clinical population. Copyright © 2010 by the Research Society on Alcoholism.
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.
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.
Episodic and Semantic Autobiographical Memory in Adults with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Crane, Laura; Goddard, Lorna

2008-01-01

Episodic and semantic autobiographical memories were examined in a group of adults with autism spectrum disorders (ASD) and a control group matched for age, gender and IQ. Results demonstrated a personal episodic memory deficit in the ASD group in the absence of a personal semantic memory deficit, suggesting a deficit dissociation between these…
Episodic Autobiographical Memories over the Course of Time: Cognitive, Neuropsychological and Neuroimaging Findings

ERIC Educational Resources Information Center

Piolino, Pascale; Desgranges, Beatrice; Eustache, Francis

2009-01-01

The critical attributes of episodic memory are self, autonoetic consciousness and subjectively sensed time. The aim of this paper is to present a theoretical overview of our already published researches into the nature of episodic memory over the course of time. We have developed a new method of assessing "autobiographical" memory (TEMPau task),…
Remembering in Contradictory Minds: Disjunction Fallacies in Episodic Memory

ERIC Educational Resources Information Center

Brainerd, C. J.; Reyna, V. F.; Aydin, C.

2010-01-01

Disjunction fallacies have been extensively studied in probability judgment. They should also occur in episodic memory, if remembering a cue's episodic state depends on how its state is described on a memory test (e.g., being described as a target vs. as a distractor). If memory is description-dependent, cues will be remembered as occupying…
Glycated haemoglobin (HbA1c), diabetes and trajectories of change in episodic memory performance.

PubMed

Pappas, Colleen; Andel, Ross; Infurna, Frank J; Seetharaman, Shyam

2017-02-01

As the ageing population grows, it is important to identify strategies to moderate cognitive ageing. We examined glycated haemoglobin (HbA1c) and diabetes in relation to level and change in episodic memory in older adults with and without diabetes. Data from 4419 older adults with (n=950) and without (n=3469) diabetes participating in a nationally representative longitudinal panel study (the Health and Retirement Study) were examined. Average baseline age was 72.66 years and 58% were women. HbA1c was measured in 2006 and episodic memory was measured using immediate and delayed list recall over 4 biennial waves between 2006 and 2012. Growth curve models were used to assess trajectories of episodic memory change. In growth curve models adjusted for age, sex, education, race, depressive symptoms and waist circumference, higher HbA1c levels and having diabetes were associated with poorer baseline episodic memory (p=0.036 and <0.001, respectively) and greater episodic memory decline (p=0.006 and 0.004, respectively). The effect of HbA1c on episodic memory decline was smaller than the effect of age. The results were stronger for women than men and were not modified by age or race. When the main analyses were estimated for those with and without diabetes separately, HbA1c was significantly linked to change in episodic memory only among those with diabetes. Higher HbA1c and diabetes were both associated with declines in episodic memory, with this relationship further exacerbated by having diabetes and elevated HbA1c. HbA1c appeared more important for episodic memory performance among women than men. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
[Episodic autobiographical memory in depression: a review].

PubMed

Lemogne, C; Piolino, P; Jouvent, R; Allilaire, J-F; Fossati, P

2006-10-01

Autobiographical memory and personal identity (self) are linked by a reciprocal relationship. Autobiographical memory is critical for both grounding and changing the self. Individuals' current self-views, beliefs, and goals influence their recollections of the past. According to Tulving, episodic memory is characterized by autonoetic consciousness, which is associated with a sense of the self in the past (emotions and goals) and mental reliving of an experience. Its close relationship with self and emotion strongly involves episodic autobiographical memory in the psychopathology of depression. However, due to methodological and conceptual issues, little attention has been paid to episodic autobiographical memory in depression. Since the seminal work of Williams et al. 15 years ago, there is now growing interest around this issue. We reviewed the evidence for three major features of autobiographical memory functioning in depression: an increase in general memory retrieval (overgenerality), a mood-congruent memory effect and the high occurrence of intrusive memories of stressful events. Although it was first observed among suicidal patients, overgenerality is actually associated with both depression and post-traumatic stress disorder. Overgenerality is not associated with anxious disorders other than post-traumatic stress disorder, obsessive-compulsive disorder, or borderline personality disorder. Most of controlled studies carried out on autobiographical memory in depression rely on the Williams' Autobiographical Memory Test (AMT). When presented with positive and negative cue words and asked to retrieve specific personal events, depressed patients (unlike matched controls) are less specific in their memories. They tend to recall repeated events (categorical overgeneral memories) rather than single episodes (specific memories). Overgenerality in depression is: 1) more evident with positive than with negative events (mood-congruent memory effect); 2) related to avoidance of intrusive memories; 3) quite stable over time, ie, remaining after remission; and 4) related to short-term prognosis in depression. Although it is not clear whether overgenerality is a cause or an effect of depression, there is some evidence to suggest that overgenerality is a trait marker indicating vulnerability to persistent depression. Mood-congruent effect, a well-known effect in depression, has been addressed in both autobio-graphical and non-autobiographical memory. Depressed patients spontaneously recall more negative than positive memories. With the AMT, depressed patients take longer to respond to positive than to negative cues, whereas controls do the opposite. Depression is also associated with a high occurrence of spontaneous intrusive memories of stressful life events. Studies found intrusions and related avoidance, as measured by the Impact of Event Scale, to be positively correlated with overgenerality, whereas there was no direct link between performance on the Autobiographical Memory Test and stressful life events per se. Both Williams' mnemonic interlock model and Conway's self-memory system are useful models to address the complexity of findings regarding autobiographical memory and depression. According to Williams, repeated avoidance of stressful memories leads depressed patients to have an autobiographical memory functioning characterized by iterative retrievals of categorical overgeneral memories, producing an enduring overgeneral retrieval style. According to Conway, the recollection of autobiographical memories requires a retrieval process that provides access to sensory/perceptual event-specific knowledge (ie perceptions and feelings) via a personal semantic knowledge base (ie lifetime periods and generic events). This retrieval process (generative retrieval mode) relies on both executive functioning and current self-view, namely the working-self. Spontaneous memories, usually vivid, result from a direct retrieval mode in which event-specific knowledge is directly triggered. In line with this model, episodic autobiographical memory impairment in state depression may arise from the working self rather than from autobiographical knowledge. The mood-congruent effect may be explained by the current (depressed) self. The high occurrence of intrusive memories may be explained by lack of executive control during direct retrieval. Overgenerality may rely on the interaction of both executive dysfunction and current (depressed) self, within the working-self, during generative retrieval. Our review suggests that further evidence is needed to address the relationship between executive functioning, self and autobiographical memory in depression.
Transfer after process-based object-location memory training in healthy older adults.

PubMed

Zimmermann, Kathrin; von Bastian, Claudia C; Röcke, Christina; Martin, Mike; Eschen, Anne

2016-11-01

A substantial part of age-related episodic memory decline has been attributed to the decreasing ability of older adults to encode and retrieve associations among simultaneously processed information units from long-term memory. In addition, this ability seems to share unique variance with reasoning. In this study, we therefore examined whether process-based training of the ability to learn and remember associations has the potential to induce transfer effects to untrained episodic memory and reasoning tasks in healthy older adults (60-75 years). For this purpose, the experimental group (n = 36) completed 30 sessions of process-based object-location memory training, while the active control group (n = 31) practiced visual perception on the same material. Near (spatial episodic memory), intermediate (verbal episodic memory), and far transfer effects (reasoning) were each assessed with multiple tasks at four measurements (before, midway through, immediately after, and 4 months after training). Linear mixed-effects models revealed transfer effects on spatial episodic memory and reasoning that were still observed 4 months after training. These results provide first empirical evidence that process-based training can enhance healthy older adults' associative memory performance and positively affect untrained episodic memory and reasoning abilities. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Personal semantics: at the crossroads of semantic and episodic memory.

PubMed

Renoult, Louis; Davidson, Patrick S R; Palombo, Daniela J; Moscovitch, Morris; Levine, Brian

2012-11-01

Declarative memory is usually described as consisting of two systems: semantic and episodic memory. Between these two poles, however, may lie a third entity: personal semantics (PS). PS concerns knowledge of one's past. Although typically assumed to be an aspect of semantic memory, it is essentially absent from existing models of knowledge. Furthermore, like episodic memory (EM), PS is idiosyncratically personal (i.e., not culturally-shared). We show that, depending on how it is operationalized, the neural correlates of PS can look more similar to semantic memory, more similar to EM, or dissimilar to both. We consider three different perspectives to better integrate PS into existing models of declarative memory and suggest experimental strategies for disentangling PS from semantic and episodic memory. Copyright © 2012 Elsevier Ltd. All rights reserved.
Latent change models of adult cognition: are changes in processing speed and working memory associated with changes in episodic memory?

PubMed

Hertzog, Christopher; Dixon, Roger A; Hultsch, David F; MacDonald, Stuart W S

2003-12-01

The authors used 6-year longitudinal data from the Victoria Longitudinal Study (VLS) to investigate individual differences in amount of episodic memory change. Latent change models revealed reliable individual differences in cognitive change. Changes in episodic memory were significantly correlated with changes in other cognitive variables, including speed and working memory. A structural equation model for the latent change scores showed that changes in speed and working memory predicted changes in episodic memory, as expected by processing resource theory. However, these effects were best modeled as being mediated by changes in induction and fact retrieval. Dissociations were detected between cross-sectional ability correlations and longitudinal changes. Shuffling the tasks used to define the Working Memory latent variable altered patterns of change correlations.
Episodic Recollection in Animals: ''If It Walks like a Duck and Quacks like a Duck...''

ERIC Educational Resources Information Center

Eichenbaum, H.; Fortin, N.J.; Ergorul, C.; Wright, S.P.; Agster, K.L.

2005-01-01

In humans, episodic memory is most commonly defined as the subjective experience of recollection, presenting a major challenge to the identification of episodic memory in animals. Here we take the position that episodic memory also has several other distinctive qualities that can be assessed objectively in animals, as well as humans, and the…

Imaging episodic memory: implications for cognitive theories and phenomena.

PubMed

Nyberg, L

1999-01-01

Functional neuroimaging studies are beginning to identify neuroanatomical correlates of various cognitive functions. This paper presents results relevant to several theories and phenomena of episodic memory, including component processes of episodic retrieval, encoding specificity, inhibition, item versus source memory, encoding-retrieval overlap, and the picture-superiority effect. Overall, by revealing specific activation patterns, the results provide support for existing theoretical views and they add some unique information which may be important to consider in future attempts to develop cognitive theories of episodic memory.
Bridging the Gap between Brain and Behavior: Cognitive and Neural Mechanisms of Episodic Memory

PubMed Central

Eichenbaum, Howard; Fortin, Norbert J

2005-01-01

The notion that non-human animals are capable of episodic memory is highly controversial. Here, we review recent behavioral work from our laboratory showing that the fundamental features of episodic memory can be observed in rats and that, as in humans, this capacity relies on the hippocampus. We also discuss electrophysiological evidence, from our laboratory and that of others, pointing to associative and sequential coding in hippocampal cells as potential neural mechanisms underlying episodic memory. PMID:16596982
Multimodal Feature Integration in the Angular Gyrus during Episodic and Semantic Retrieval

PubMed Central

Bonnici, Heidi M.; Richter, Franziska R.; Yazar, Yasemin

2016-01-01

Much evidence from distinct lines of investigation indicates the involvement of angular gyrus (AnG) in the retrieval of both episodic and semantic information, but the region's precise function and whether that function differs across episodic and semantic retrieval have yet to be determined. We used univariate and multivariate fMRI analysis methods to examine the role of AnG in multimodal feature integration during episodic and semantic retrieval. Human participants completed episodic and semantic memory tasks involving unimodal (auditory or visual) and multimodal (audio-visual) stimuli. Univariate analyses revealed the recruitment of functionally distinct AnG subregions during the retrieval of episodic and semantic information. Consistent with a role in multimodal feature integration during episodic retrieval, significantly greater AnG activity was observed during retrieval of integrated multimodal episodic memories compared with unimodal episodic memories. Multivariate classification analyses revealed that individual multimodal episodic memories could be differentiated in AnG, with classification accuracy tracking the vividness of participants' reported recollections, whereas distinct unimodal memories were represented in sensory association areas only. In contrast to episodic retrieval, AnG was engaged to a statistically equivalent degree during retrieval of unimodal and multimodal semantic memories, suggesting a distinct role for AnG during semantic retrieval. Modality-specific sensory association areas exhibited corresponding activity during both episodic and semantic retrieval, which mirrored the functional specialization of these regions during perception. The results offer new insights into the integrative processes subserved by AnG and its contribution to our subjective experience of remembering. SIGNIFICANCE STATEMENT Using univariate and multivariate fMRI analyses, we provide evidence that functionally distinct subregions of angular gyrus (AnG) contribute to the retrieval of episodic and semantic memories. Our multivariate pattern classifier could distinguish episodic memory representations in AnG according to whether they were multimodal (audio-visual) or unimodal (auditory or visual) in nature, whereas statistically equivalent AnG activity was observed during retrieval of unimodal and multimodal semantic memories. Classification accuracy during episodic retrieval scaled with the trial-by-trial vividness with which participants experienced their recollections. Therefore, the findings offer new insights into the integrative processes subserved by AnG and how its function may contribute to our subjective experience of remembering. PMID:27194327
Multimodal Feature Integration in the Angular Gyrus during Episodic and Semantic Retrieval.

PubMed

Bonnici, Heidi M; Richter, Franziska R; Yazar, Yasemin; Simons, Jon S

2016-05-18

Much evidence from distinct lines of investigation indicates the involvement of angular gyrus (AnG) in the retrieval of both episodic and semantic information, but the region's precise function and whether that function differs across episodic and semantic retrieval have yet to be determined. We used univariate and multivariate fMRI analysis methods to examine the role of AnG in multimodal feature integration during episodic and semantic retrieval. Human participants completed episodic and semantic memory tasks involving unimodal (auditory or visual) and multimodal (audio-visual) stimuli. Univariate analyses revealed the recruitment of functionally distinct AnG subregions during the retrieval of episodic and semantic information. Consistent with a role in multimodal feature integration during episodic retrieval, significantly greater AnG activity was observed during retrieval of integrated multimodal episodic memories compared with unimodal episodic memories. Multivariate classification analyses revealed that individual multimodal episodic memories could be differentiated in AnG, with classification accuracy tracking the vividness of participants' reported recollections, whereas distinct unimodal memories were represented in sensory association areas only. In contrast to episodic retrieval, AnG was engaged to a statistically equivalent degree during retrieval of unimodal and multimodal semantic memories, suggesting a distinct role for AnG during semantic retrieval. Modality-specific sensory association areas exhibited corresponding activity during both episodic and semantic retrieval, which mirrored the functional specialization of these regions during perception. The results offer new insights into the integrative processes subserved by AnG and its contribution to our subjective experience of remembering. Using univariate and multivariate fMRI analyses, we provide evidence that functionally distinct subregions of angular gyrus (AnG) contribute to the retrieval of episodic and semantic memories. Our multivariate pattern classifier could distinguish episodic memory representations in AnG according to whether they were multimodal (audio-visual) or unimodal (auditory or visual) in nature, whereas statistically equivalent AnG activity was observed during retrieval of unimodal and multimodal semantic memories. Classification accuracy during episodic retrieval scaled with the trial-by-trial vividness with which participants experienced their recollections. Therefore, the findings offer new insights into the integrative processes subserved by AnG and how its function may contribute to our subjective experience of remembering. Copyright © 2016 Bonnici, Richter, et al.
Role of PFC during retrieval of recognition memory in rodents.

PubMed

Bekinschtein, Pedro; Weisstaub, Noelia

2014-01-01

One of the challenges for memory researches is the study of the neurobiology of episodic memory which is defined by the integration of all the different components of experiences that support the conscious recollection of events. The features of episodic memory includes a particular object or person ("what"), the context in which the experience took place ("where") and the particular time at which the event occurred ("when"). Although episodic memory has been mainly studied in humans, there are many studies that demonstrate these features in non-human animals. Here, we summarize a set of studies that employ different versions of recognition memory tasks in animals to study the role of the medial prefrontal cortex in episodic memory. Copyright © 2014 Elsevier Ltd. All rights reserved.
The Interaction between Semantic Representation and Episodic Memory.

PubMed

Fang, Jing; Rüther, Naima; Bellebaum, Christian; Wiskott, Laurenz; Cheng, Sen

2018-02-01

The experimental evidence on the interrelation between episodic memory and semantic memory is inconclusive. Are they independent systems, different aspects of a single system, or separate but strongly interacting systems? Here, we propose a computational role for the interaction between the semantic and episodic systems that might help resolve this debate. We hypothesize that episodic memories are represented as sequences of activation patterns. These patterns are the output of a semantic representational network that compresses the high-dimensional sensory input. We show quantitatively that the accuracy of episodic memory crucially depends on the quality of the semantic representation. We compare two types of semantic representations: appropriate representations, which means that the representation is used to store input sequences that are of the same type as those that it was trained on, and inappropriate representations, which means that stored inputs differ from the training data. Retrieval accuracy is higher for appropriate representations because the encoded sequences are less divergent than those encoded with inappropriate representations. Consistent with our model prediction, we found that human subjects remember some aspects of episodes significantly more accurately if they had previously been familiarized with the objects occurring in the episode, as compared to episodes involving unfamiliar objects. We thus conclude that the interaction with the semantic system plays an important role for episodic memory.
Evidence of episodic-like memory in cuttlefish.

PubMed

Jozet-Alves, Christelle; Bertin, Marion; Clayton, Nicola S

2013-12-02

The recollection of past experiences allows us to recall what happened during a particular event, and where and when it occurred [1]. Since the first study on episodic-like memory in scrub-jays [2], there has been widespread acceptance of the idea that tests in animals should integrate the 'what', 'where' and 'when' components of a unique event that occurred in the past [3,4]. This is referred to as episodic-like memory rather than episodic memory per se, in acknowledgement of the lack of evidence for, or against, the phenomenological aspects that accompany episodic recollection in humans. So far, evidence for episodic-like memory has only been found in some birds and mammals. We show here that cuttlefish, cephalopod mollusks, keep track of what they have eaten, and where and how long ago they ate, in order to match their foraging behavior with the time of replenishing of different foods. Foraging in cuttlefish fulfils the criteria of 'what', 'where' and 'when' of unique events and thus provides behavioral evidence of episodic-like memory in an invertebrate. Copyright © 2013 Elsevier Ltd. All rights reserved.
The Construction of Semantic Memory: Grammar-Based Representations Learned from Relational Episodic Information

PubMed Central

Battaglia, Francesco P.; Pennartz, Cyriel M. A.

2011-01-01

After acquisition, memories underlie a process of consolidation, making them more resistant to interference and brain injury. Memory consolidation involves systems-level interactions, most importantly between the hippocampus and associated structures, which takes part in the initial encoding of memory, and the neocortex, which supports long-term storage. This dichotomy parallels the contrast between episodic memory (tied to the hippocampal formation), collecting an autobiographical stream of experiences, and semantic memory, a repertoire of facts and statistical regularities about the world, involving the neocortex at large. Experimental evidence points to a gradual transformation of memories, following encoding, from an episodic to a semantic character. This may require an exchange of information between different memory modules during inactive periods. We propose a theory for such interactions and for the formation of semantic memory, in which episodic memory is encoded as relational data. Semantic memory is modeled as a modified stochastic grammar, which learns to parse episodic configurations expressed as an association matrix. The grammar produces tree-like representations of episodes, describing the relationships between its main constituents at multiple levels of categorization, based on its current knowledge of world regularities. These regularities are learned by the grammar from episodic memory information, through an expectation-maximization procedure, analogous to the inside–outside algorithm for stochastic context-free grammars. We propose that a Monte-Carlo sampling version of this algorithm can be mapped on the dynamics of “sleep replay” of previously acquired information in the hippocampus and neocortex. We propose that the model can reproduce several properties of semantic memory such as decontextualization, top-down processing, and creation of schemata. PMID:21887143
Elaboration versus suppression of cued memories: influence of memory recall instruction and success on parietal lobe, default network, and hippocampal activity.

PubMed

Gimbel, Sarah I; Brewer, James B

2014-01-01

Functional imaging studies of episodic memory retrieval consistently report task-evoked and memory-related activity in the medial temporal lobe, default network and parietal lobe subregions. Associated components of memory retrieval, such as attention-shifts, search, retrieval success, and post-retrieval processing also influence regional activity, but these influences remain ill-defined. To better understand how top-down control affects the neural bases of memory retrieval, we examined how regional activity responses were modulated by task goals during recall success or failure. Specifically, activity was examined during memory suppression, recall, and elaborative recall of paired-associates. Parietal lobe was subdivided into dorsal (BA 7), posterior ventral (BA 39), and anterior ventral (BA 40) regions, which were investigated separately to examine hypothesized distinctions in sub-regional functional responses related to differential attention-to-memory and memory strength. Top-down suppression of recall abolished memory strength effects in BA 39, which showed a task-negative response, and BA 40, which showed a task-positive response. The task-negative response in default network showed greater negatively-deflected signal for forgotten pairs when task goals required recall. Hippocampal activity was task-positive and was influenced by memory strength only when task goals required recall. As in previous studies, we show a memory strength effect in parietal lobe and hippocampus, but we show that this effect is top-down controlled and sensitive to whether the subject is trying to suppress or retrieve a memory. These regions are all implicated in memory recall, but their individual activity patterns show distinct memory-strength-related responses when task goals are varied. In parietal lobe, default network, and hippocampus, top-down control can override the commonly identified effects of memory strength.
Elaboration versus Suppression of Cued Memories: Influence of Memory Recall Instruction and Success on Parietal Lobe, Default Network, and Hippocampal Activity

PubMed Central

Gimbel, Sarah I.; Brewer, James B.

2014-01-01

Functional imaging studies of episodic memory retrieval consistently report task-evoked and memory-related activity in the medial temporal lobe, default network and parietal lobe subregions. Associated components of memory retrieval, such as attention-shifts, search, retrieval success, and post-retrieval processing also influence regional activity, but these influences remain ill-defined. To better understand how top-down control affects the neural bases of memory retrieval, we examined how regional activity responses were modulated by task goals during recall success or failure. Specifically, activity was examined during memory suppression, recall, and elaborative recall of paired-associates. Parietal lobe was subdivided into dorsal (BA 7), posterior ventral (BA 39), and anterior ventral (BA 40) regions, which were investigated separately to examine hypothesized distinctions in sub-regional functional responses related to differential attention-to-memory and memory strength. Top-down suppression of recall abolished memory strength effects in BA 39, which showed a task-negative response, and BA 40, which showed a task-positive response. The task-negative response in default network showed greater negatively-deflected signal for forgotten pairs when task goals required recall. Hippocampal activity was task-positive and was influenced by memory strength only when task goals required recall. As in previous studies, we show a memory strength effect in parietal lobe and hippocampus, but we show that this effect is top-down controlled and sensitive to whether the subject is trying to suppress or retrieve a memory. These regions are all implicated in memory recall, but their individual activity patterns show distinct memory-strength-related responses when task goals are varied. In parietal lobe, default network, and hippocampus, top-down control can override the commonly identified effects of memory strength. PMID:24586492
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.
Rapid formation and flexible expression of memories of subliminal word pairs.

PubMed

Reber, Thomas P; Henke, Katharina

2011-01-01

Our daily experiences are incidentally and rapidly encoded as episodic memories. Episodic memories consist of numerous associations (e.g., who gave what to whom where and when) that can be expressed flexibly in new situations. Key features of episodic memory are speed of encoding, its associative nature, and its representational flexibility. Another defining feature of human episodic memory has been consciousness of encoding/retrieval. Here, we show that humans can rapidly form associations between subliminal words and minutes later retrieve these associations even if retrieval words were conceptually related to, but different from encoding words. Because encoding words were presented subliminally, associative encoding, and retrieval were unconscious. Unconscious association formation and retrieval were dependent on a preceding understanding of task principles. We conclude that key computations underlying episodic memory - rapid encoding and flexible expression of associations - can operate outside consciousness.
A Role for the Left Angular Gyrus in Episodic Simulation and Memory.

PubMed

Thakral, Preston P; Madore, Kevin P; Schacter, Daniel L

2017-08-23

Functional magnetic resonance imaging (fMRI) studies indicate that episodic simulation (i.e., imagining specific future experiences) and episodic memory (i.e., remembering specific past experiences) are associated with enhanced activity in a common set of neural regions referred to as the core network. This network comprises the hippocampus, medial prefrontal cortex, and left angular gyrus, among other regions. Because fMRI data are correlational, it is unknown whether activity increases in core network regions are critical for episodic simulation and episodic memory. In the current study, we used MRI-guided transcranial magnetic stimulation (TMS) to assess whether temporary disruption of the left angular gyrus would impair both episodic simulation and memory (16 participants, 10 females). Relative to TMS to a control site (vertex), disruption of the left angular gyrus significantly reduced the number of internal (i.e., episodic) details produced during the simulation and memory tasks, with a concomitant increase in external detail production (i.e., semantic, repetitive, or off-topic information), reflected by a significant detail by TMS site interaction. Difficulty in the simulation and memory tasks also increased after TMS to the left angular gyrus relative to the vertex. In contrast, performance in a nonepisodic control task did not differ statistically as a function of TMS site (i.e., number of free associates produced or difficulty in performing the free associate task). Together, these results are the first to demonstrate that the left angular gyrus is critical for both episodic simulation and episodic memory. SIGNIFICANCE STATEMENT Humans have the ability to imagine future episodes (i.e., episodic simulation) and remember episodes from the past (i.e., episodic memory). A wealth of neuroimaging studies have revealed that these abilities are associated with enhanced activity in a core network of neural regions, including the hippocampus, medial prefrontal cortex, and left angular gyrus. However, neuroimaging data are correlational and do not tell us whether core regions support critical processes for simulation and memory. In the current study, we used transcranial magnetic stimulation and demonstrated that temporary disruption of the left angular gyrus leads to impairments in simulation and memory. The present study provides the first causal evidence to indicate that this region is critical for these fundamental abilities. Copyright © 2017 the authors 0270-6474/17/378142-08$15.00/0.
A Role for the Left Angular Gyrus in Episodic Simulation and Memory

PubMed Central

2017-01-01

Functional magnetic resonance imaging (fMRI) studies indicate that episodic simulation (i.e., imagining specific future experiences) and episodic memory (i.e., remembering specific past experiences) are associated with enhanced activity in a common set of neural regions referred to as the core network. This network comprises the hippocampus, medial prefrontal cortex, and left angular gyrus, among other regions. Because fMRI data are correlational, it is unknown whether activity increases in core network regions are critical for episodic simulation and episodic memory. In the current study, we used MRI-guided transcranial magnetic stimulation (TMS) to assess whether temporary disruption of the left angular gyrus would impair both episodic simulation and memory (16 participants, 10 females). Relative to TMS to a control site (vertex), disruption of the left angular gyrus significantly reduced the number of internal (i.e., episodic) details produced during the simulation and memory tasks, with a concomitant increase in external detail production (i.e., semantic, repetitive, or off-topic information), reflected by a significant detail by TMS site interaction. Difficulty in the simulation and memory tasks also increased after TMS to the left angular gyrus relative to the vertex. In contrast, performance in a nonepisodic control task did not differ statistically as a function of TMS site (i.e., number of free associates produced or difficulty in performing the free associate task). Together, these results are the first to demonstrate that the left angular gyrus is critical for both episodic simulation and episodic memory. SIGNIFICANCE STATEMENT Humans have the ability to imagine future episodes (i.e., episodic simulation) and remember episodes from the past (i.e., episodic memory). A wealth of neuroimaging studies have revealed that these abilities are associated with enhanced activity in a core network of neural regions, including the hippocampus, medial prefrontal cortex, and left angular gyrus. However, neuroimaging data are correlational and do not tell us whether core regions support critical processes for simulation and memory. In the current study, we used transcranial magnetic stimulation and demonstrated that temporary disruption of the left angular gyrus leads to impairments in simulation and memory. The present study provides the first causal evidence to indicate that this region is critical for these fundamental abilities. PMID:28733357
Study on memories of temporal lobes and the principles of lateralization using near infrared spectroscopy

NASA Astrophysics Data System (ADS)

Kamakura, Katsutoshi

2007-01-01

In this study we measured the variation of brain blood quantity (Oxy-Hb, Deoxy-Hb and Total-Hb) in the temporal lobes using near infrared spectroscopy (NIRS) when the tasks of the memories were presented to the subjects. The memories are classified into the short-term memory (STM) and the long-term memory (LTM) including the episodic and semantic memories. The subjects joined in this study are 11 persons who are university students including graduate students. We used the language task of letter-number sequencing, also reverse sequencing to measure STM and the task of the episodic memory to measure LTM. As a result of analysis, concerning the episodic memory, the variation of Oxy-Hb in the left temporal lobe was larger than that of Oxy-Hb in the right temporal lobe. The result might suggest that the episodic memory has a relationship with cerebral dominance concerning language area in the left temporal lobe. It seems that the episodic memory meditated with the function of language used in this study is much stored in the left temporal lobe than in the right temporal lobe. This result coincides with the principles of lateralization. The variation of Oxy-Hb in the language task of letter-number sequencing was smaller than that of Oxy-Hb in the language task of the episodic memory.
A Calendar Savant with Episodic Memory Impairments

PubMed Central

Olson, Ingrid R.; Berryhill, Marian E.; Drowos, David B.; Brown, Lawrence; Chatterjee, Anjan

2010-01-01

Patients with memory disorders have severely restricted learning and memory. For instance, patients with anterograde amnesia can learn motor procedures as well as retaining some restricted ability to learn new words and factual information. However, such learning is inflexible and frequently inaccessible to conscious awareness. Here we present a case of patient AC596, a 25-year old male with severe episodic memory impairments, presumably due to anoxia during a preterm birth. In contrast to his poor episodic memory, he exhibits savant-like memory for calendar information that can be flexibly accessed by day, month, and year cues. He also has the ability to recollect the exact date of a wide range of personal experiences over the past 20 years. The patient appears to supplement his generally poor episodic memory by using memorized calendar information as a retrieval cue for autobiographical events. These findings indicate that islands of preserved memory functioning, such as a highly developed semantic memory system, can exist in individuals with severely impaired episodic memory systems. In this particular case, our patient’s memory for dates far outstripped that of normal individuals and served as a keen retrieval cue, allowing him to access information that was otherwise unavailable. PMID:20104390
Episodic Memory and Beyond: The Hippocampus and Neocortex in Transformation

PubMed Central

Moscovitch, Morris; Cabeza, Roberto; Winocur, Gordon; Nadel, Lynn

2016-01-01

The last decade has seen dramatic technological and conceptual changes in research on episodic memory and the brain. New technologies, and increased use of more naturalistic observations, have enabled investigators to delve deeply into the structures that mediate episodic memory, particularly the hippocampus, and to track functional and structural interactions among brain regions that support it. Conceptually, episodic memory is increasingly being viewed as subject to lifelong transformations that are reflected in the neural substrates that mediate it. In keeping with this dynamic perspective, research on episodic memory (and the hippocampus) has infiltrated domains, from perception to language and from empathy to problem solving, that were once considered outside its boundaries. Using the component process model as a framework, and focusing on the hippocampus, its subfields, and specialization along its longitudinal axis, along with its interaction with other brain regions, we consider these new developments and their implications for the organization of episodic memory and its contribution to functions in other domains. PMID:26726963
Episodic Memory and Beyond: The Hippocampus and Neocortex in Transformation.

PubMed

Moscovitch, Morris; Cabeza, Roberto; Winocur, Gordon; Nadel, Lynn

2016-01-01

The last decade has seen dramatic technological and conceptual changes in research on episodic memory and the brain. New technologies, and increased use of more naturalistic observations, have enabled investigators to delve deeply into the structures that mediate episodic memory, particularly the hippocampus, and to track functional and structural interactions among brain regions that support it. Conceptually, episodic memory is increasingly being viewed as subject to lifelong transformations that are reflected in the neural substrates that mediate it. In keeping with this dynamic perspective, research on episodic memory (and the hippocampus) has infiltrated domains, from perception to language and from empathy to problem solving, that were once considered outside its boundaries. Using the component process model as a framework, and focusing on the hippocampus, its subfields, and specialization along its longitudinal axis, along with its interaction with other brain regions, we consider these new developments and their implications for the organization of episodic memory and its contribution to functions in other domains.
Neutral and emotional episodic memory: global impairment after lorazepam or scopolamine.

PubMed

Kamboj, Sunjeev K; Curran, H Valerie

2006-11-01

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

Longitudinal Study of a Novel, Performance-based Measure of Daily Function

DTIC Science & Technology

2016-06-01

have functional impairments, and healthy age matched controls on the UPSA, as well as measures of cognition (e.g., episodic memory , semantic memory ...controls on the UPSA, as well as measures of cognition (e.g., episodic memory , semantic memory , executive function, speed). We found that patients with...diagnosis have functional impairments, and healthy age matched controls on the UPSA, as well as measures of cognition (e.g., episodic memory , semantic
Similar profile of cognitive impairment and recovery for Aboriginal Australians in treatment for episodic or chronic alcohol use.

PubMed

Dingwall, Kylie M; Maruff, Paul; Cairney, Sheree

2011-08-01

The cognitive impairment and recovery associated with chronic alcohol abuse and subsequent abstinence is well understood. However, the recovery profile following heavy episodic or 'binge' use, which is common among some Australian Aboriginal users, has not been investigated thoroughly and no empirical studies have examined chronic use in this population. The aim of this study was to identify and compare cognitive impairment and recovery associated with chronic and episodic alcohol use among Aboriginal Australians. Longitudinal case-control design. Residential alcohol treatment programmes in northern Australia. Forty chronic alcohol users, 24 episodic users and 41 healthy controls [mean age = 34.24; standard deviation (SD) = 9.73]. Cognitive assessments of visual motor, attention, memory, learning and executive functions at baseline (start of treatment), then 4 weeks and 8 weeks later. Reassessment of 31% of participants an average of 11 months later (SD = 4.4) comparing those who remained abstinent (n = 5), those who relapsed (n = 11) and healthy controls (n = 19). At baseline, chronic and episodic alcohol users showed impaired visual motor, learning, memory and executive functions. With the exception of visual motor impairment, all deficits had improved to normal levels within 4 weeks. Visual motor deficits had normalized within 11 months. Performances did not differ at any time between chronic and episodic alcohol groups. In Aboriginal Australians, episodic drinking is associated with similar patterns of impairment and recovery as chronic alcohol use. Most cognitive deficits appear to recover within the first month of abstinence, while persisting visual motor problems recover within 1 year. © 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.
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.
Elements of episodic-like memory in animals.

PubMed

Clayton, N S; Griffiths, D P; Emery, N J; Dickinson, A

2001-09-29

A number of psychologists have suggested that episodic memory is a uniquely human phenomenon and, until recently, there was little evidence that animals could recall a unique past experience and respond appropriately. Experiments on food-caching memory in scrub jays question this assumption. On the basis of a single caching episode, scrub jays can remember when and where they cached a variety of foods that differ in the rate at which they degrade, in a way that is inexplicable by relative familiarity. They can update their memory of the contents of a cache depending on whether or not they have emptied the cache site, and can also remember where another bird has hidden caches, suggesting that they encode rich representations of the caching event. They make temporal generalizations about when perishable items should degrade and also remember the relative time since caching when the same food is cached in distinct sites at different times. These results show that jays form integrated memories for the location, content and time of caching. This memory capability fulfils Tulving's behavioural criteria for episodic memory and is thus termed 'episodic-like'. We suggest that several features of episodic memory may not be unique to humans.
The medial prefrontal cortex-lateral entorhinal cortex circuit is essential for episodic-like memory and associative object-recognition.

PubMed

Chao, Owen Y; Huston, Joseph P; Li, Jay-Shake; Wang, An-Li; de Souza Silva, Maria A

2016-05-01

The prefrontal cortex directly projects to the lateral entorhinal cortex (LEC), an important substrate for engaging item-associated information and relaying the information to the hippocampus. Here we ask to what extent the communication between the prefrontal cortex and LEC is critically involved in the processing of episodic-like memory. We applied a disconnection procedure to test whether the interaction between the medial prefrontal cortex (mPFC) and LEC is essential for the expression of recognition memory. It was found that male rats that received unilateral NMDA lesions of the mPFC and LEC in the same hemisphere, exhibited intact episodic-like (what-where-when) and object-recognition memories. When these lesions were placed in the opposite hemispheres (disconnection), episodic-like and associative memories for object identity, location and context were impaired. However, the disconnection did not impair the components of episodic memory, namely memory for novel object (what), object place (where) and temporal order (when), per se. Thus, the present findings suggest that the mPFC and LEC are a critical part of a neural circuit that underlies episodic-like and associative object-recognition memory. © 2015 Wiley Periodicals, Inc.
Evidence in Favor of the Early-Phase Elevated-Attention Hypothesis: The Effects of Letter Frequency and Object Frequency

ERIC Educational Resources Information Center

Criss, Amy H.; Malmberg, Kenneth J.

2008-01-01

One of the most studied and least well understood phenomena in episodic memory is the word frequency effect (WFE). The WFE is expressed as a mirror pattern where uncommon low frequency words (LF) are better recognized than common high frequency words (HF) by way of a higher HR and lower FAR. One explanation for the HR difference is the early-phase…
Developmental amnesia: Fractionation of developing memory systems.

PubMed

Temple, Christine M; Richardson, Paul

2006-07-01

Study of the developmental amnesias utilizing a cognitive neuropsychological methodology has highlighted the dissociations that may occur between the development of components of memory. M.M., a new case of developmental amnesia, was identified after screening from the normal population on cognitive and memory measures. Retrospective investigation found that he was of low birthweight. M.M. had impaired semantic memory for knowledge of facts and words. There was impaired episodic memory for words and stories but intact episodic memory for visual designs and features. This forms a double dissociation with Dr S. (Temple, 1992), who had intact verbal but impaired visual episodic memory. M.M. also had impaired autobiographical episodic memory. Nevertheless, learning over repeated trials occurred, consistent with previous theorizing that learning is not simply the effect of recurrent episodic memory. Nor is it the same as establishing semantic memory, since for M.M. semantic memory is also impaired. Within reading, there was an impaired lexico-semantic system, elevated levels of homophone confusion, but intact phonological reading, consistent with surface dyslexia and raising issues about the interrelationship of the semantic system and literacy development. The results are compatible with discrete semi-independent components within memory development, whereby deficits are associated with residual normality, but there may also be an explicit relationship between the semantic memory system and both vocabulary and reading acquisition.
Residual memory dysfunction in recurrent major depressive disorder--a longitudinal study from Juntendo University Mood Disorder Project.

PubMed

Maeshima, Hitoshi; Baba, Hajime; Nakano, Yoshiyuki; Satomura, Emi; Namekawa, Yuki; Takebayashi, Naoko; Suzuki, Toshihito; Mimura, Masaru; Arai, Heii

2012-12-20

Depression may increase the risk of developing Alzheimer's disease. Large cohort studies have shown that recurrent depression is associated with a risk of developing dementia. Other studies have documented smaller hippocampal volume in patients with recurrent depression. It is speculative that a greater risk of developing dementia may result from a higher number of previous depressive episodes. This study compared patients with recurrent and single-episode depression in the remitted stage, and healthy controls to elucidate the impact of the number of depressive episodes on memory. Logical memory and visual reproduction subtests of the Wechsler Memory Scale-Revised were given to 68 patients with major depressive disorder (MDD) (30 patients with a single episode and residual 38 patients with recurrent multiple episodes) and 57 healthy controls. The patients with MDD received memory assessment at the time of initial remission and at the follow-up period 3 years after remission. At the time of initial remission, scores of both logical memory and visual reproduction subtests were significantly lower in both patient groups compared with healthy controls. At follow-up, memory dysfunction of the single-episode group disappeared, whereas scores in the recurrent group remained significantly lower than those of the single-episode group and controls. All patients in the present study were on antidepressant medications. Patients with recurrent MDD with multiple depressive episodes showed residual memory dysfunction even after 3 years of remission. Persistence of memory deficits in the recurrent depression may be a risk factor for developing dementia. Copyright © 2012 Elsevier B.V. All rights reserved.
Plasma and serum brain-derived neurotrophic factor (BDNF) levels and their association with neurocognition in at-risk mental state, first episode psychosis and chronic schizophrenia patients.

PubMed

Heitz, Ulrike; Papmeyer, Martina; Studerus, Erich; Egloff, Laura; Ittig, Sarah; Andreou, Christina; Vogel, Tobias; Borgwardt, Stefan; Graf, Marc; Eckert, Anne; Riecher-Rössler, Anita

2018-06-25

Brain-derived neurotrophic factor (BDNF) is involved in numerous cognitive processes. Since cognitive deficits are a core feature of psychotic disorders, the investigation of BDNF levels in psychosis and their correlation with cognition has received increased attention. However, there are no studies investigating BDNF levels in individuals with an at-risk mental state (ARMS) for psychosis. Hence, the aims of the present study were: (1) assessing peripheral BDNF levels across different (potential) stages of psychosis; (2) investigating their association with cognition. Plasma and serum BDNF levels and neuropsychological performance were assessed in 16 ARMS, six first-episode psychosis (FEP), and 11 chronic schizophrenia (CS) patients. Neuropsychological assessment covered intelligence, verbal memory, working memory, attention and executive functioning. Both plasma and serum BDNF levels were highest in CS, intermediate in FEP and lowest in ARMS. Multiple regression analysis revealed a significant positive association of plasma BDNF levels with planning ability across all groups. The lower peripheral BDNF levels in ARMS compared to FEP and CS might point towards an important drop of this neurotrophin prior to the onset of frank psychosis. The associations of peripheral BDNF with planning-abilities match previous findings.
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
Episodic Memory in Detoxified Alcoholics: Contribution of Grey Matter Microstructure Alteration

PubMed Central

Chanraud, Sandra; Leroy, Claire; Martelli, Catherine; Kostogianni, Nikoleta; Delain, Françoise; Aubin, Henri-Jean; Reynaud, Michel; Martinot, Jean-Luc

2009-01-01

Even though uncomplicated alcoholics may likely have episodic memory deficits, discrepancies exist regarding to the integrity of brain regions that underlie this function in healthy subjects. Possible relationships between episodic memory and 1) brain microstructure assessed by magnetic resonance diffusion tensor imaging (DTI), 2) brain volumes assessed by voxel-based morphometry (VBM) were investigated in uncomplicated, detoxified alcoholics. Diffusion and morphometric analyses were performed in 24 alcohol dependent men without neurological or somatic complications and in 24 healthy men. The mean apparent coefficient of diffusion (ADC) and grey matter volumes were measured in the whole brain. Episodic memory performance was assessed using a French version of the Free and Cued Selective Reminding Test (FCSRT). Correlation analyses between verbal episodic memory, brain microstructure, and brain volumes were carried out using SPM2 software. In those with alcohol dependence, higher ADC was detected mainly in frontal, temporal and parahippocampal regions, and in the cerebellum. In alcoholics, regions with higher ADC typically also had lower grey matter volume. Low verbal episodic memory performance in alcoholism was associated with higher mean ADC in parahippocampal areas, in frontal cortex and in the left temporal cortex; no correlation was found between regional volumes and episodic memory scores. Regression analyses for the control group were not significant. These findings support the hypothesis that regional microstructural but no macrostructural alteration of the brain might be responsible, at least in part, for episodic memory deficits in alcohol dependence. PMID:19707568
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.
Why do we remember? The communicative function of episodic memory.

PubMed

Mahr, Johannes; Csibra, Gergely

2017-01-19

Episodic memory has been analyzed in a number of different ways in both philosophy and psychology, and most controversy has centered on its self-referential, 'autonoetic' character. Here, we offer a comprehensive characterization of episodic memory in representational terms, and propose a novel functional account on this basis. We argue that episodic memory should be understood as a distinctive epistemic attitude taken towards an event simulation. On this view, episodic memory has a metarepresentational format and should not be equated with beliefs about the past. Instead, empirical findings suggest that the contents of human episodic memory are often constructed in the service of the explicit justification of such beliefs. Existing accounts of episodic memory function that have focused on explaining its constructive character through its role in 'future-oriented mental time travel' neither do justice to its capacity to ground veridical beliefs about the past nor to its representational format. We provide an account of the metarepresentational structure of episodic memory in terms of its role in communicative interaction. The generative nature of recollection allows us to represent and communicate the reasons for why we hold certain beliefs about the past. In this process, autonoesis corresponds to the capacity to determine when and how to assert epistemic authority in making claims about the past. A domain where such claims are indispensable are human social engagements. Such engagements commonly require the justification of entitlements and obligations, which is often possible only by explicit reference to specific past events.
[Higher Brain Dysfunction in Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis and Stroke-Like Episodes (MELAS)].

PubMed

Ichikawa, Hiroo

2016-02-01

Stroke-like episodes are one of the cardinal features of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), and occur in 84-99% of the patients. The affected areas detected on neuroimaging do not have classical vascular distribution, and involve predominantly the temporal, parietal and occipital lobes. Thus, the neurological symptoms including higher brain dysfunction correlate with this topographical distribution. In association with the occipital lobe involvement, the most frequent symptom is cortical blindness. Other symptoms have been occasionally reported in case reports: visual agnosia, prosopagnosia, cortical deafness, auditory agnosia, topographical disorientation, various types of aphasia, hemispatial neglect, and so on. On the other hand, cognitive decline associated with more diffuse brain impairment rather than with focal stroke-like lesions has been postulated. This condition is also known as mitochondrial dementia. Domains of cognitive dysfunction include abstract reasoning, verbal memory, visual memory, language (naming and fluency), executive or constructive functions, attention, and visuospatial function. Cognitive functions and intellectual abilities may decline from initially minimal cognitive impairment to dementia. To date, the neuropsychological and neurologic impairment has been reported to be associated with cerebral lactic acidosis as estimated by ventricular spectroscopic lactate levels.
Overlap in the functional neural systems involved in semantic and episodic memory retrieval.

PubMed

Rajah, M N; McIntosh, A R

2005-03-01

Neuroimaging and neuropsychological data suggest that episodic and semantic memory may be mediated by distinct neural systems. However, an alternative perspective is that episodic and semantic memory represent different modes of processing within a single declarative memory system. To examine whether the multiple or the unitary system view better represents the data we conducted a network analysis using multivariate partial least squares (PLS ) activation analysis followed by covariance structural equation modeling (SEM) of positron emission tomography data obtained while healthy adults performed episodic and semantic verbal retrieval tasks. It is argued that if performance of episodic and semantic retrieval tasks are mediated by different memory systems, then there should differences in both regional activations and interregional correlations related to each type of retrieval task, respectively. The PLS results identified brain regions that were differentially active during episodic retrieval versus semantic retrieval. Regions that showed maximal differences in regional activity between episodic retrieval tasks were used to construct separate functional models for episodic and semantic retrieval. Omnibus tests of these functional models failed to find a significant difference across tasks for both functional models. The pattern of path coefficients for the episodic retrieval model were not different across tasks, nor were the path coefficients for the semantic retrieval model. The SEM results suggest that the same memory network/system was engaged across tasks, given the similarities in path coefficients. Therefore, activation differences between episodic and semantic retrieval may ref lect variation along a continuum of processing during task performance within the context of a single memory system.
Episodic memory and executive functioning in currently depressed patients compared to healthy controls.

PubMed

Pauls, Franz; Petermann, Franz; Lepach, Anja Christina

2015-01-01

At present, little is still known about the link between depression, memory and executive functioning. This study examined whether there are memory-related impairments in depressed patients and whether the size of such deficits depends on the age group and on specific types of cognitive measures. Memory performances of 215 clinically depressed patients were compared to the data of a matched control sample. Regression analyses were performed to determine the extent to which executive dysfunctions contributed to episodic memory impairments. When compared with healthy controls, significantly lower episodic memory and executive functioning performances were found for depressed patients of all age groups. Effect sizes appeared to vary across different memory and executive functioning measures. The extent to which executive dysfunctions could explain episodic memory impairments varied depending on the type of measure examined. These findings emphasise the need to consider memory-related functioning of depressed patients in the context of therapeutic treatments.
Working memory training and semantic structuring improves remembering future events, not past events.

PubMed

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

2015-01-01

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

PubMed Central

Suddendorf, Thomas; Addis, Donna Rose; Corballis, Michael C.

2009-01-01

Episodic memory, enabling conscious recollection of past episodes, can be distinguished from semantic memory, which stores enduring facts about the world. Episodic memory shares a core neural network with the simulation of future episodes, enabling mental time travel into both the past and the future. The notion that there might be something distinctly human about mental time travel has provoked ingenious attempts to demonstrate episodic memory or future simulation in non-human animals, but we argue that they have not yet established a capacity comparable to the human faculty. The evolution of the capacity to simulate possible future events, based on episodic memory, enhanced fitness by enabling action in preparation of different possible scenarios that increased present or future survival and reproduction chances. Human language may have evolved in the first instance for the sharing of past and planned future events, and, indeed, fictional ones, further enhancing fitness in social settings. PMID:19528013
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.
Telling true from false: cannabis users show increased susceptibility to false memories.

PubMed

Riba, J; Valle, M; Sampedro, F; Rodríguez-Pujadas, A; Martínez-Horta, S; Kulisevsky, J; Rodríguez-Fornells, A

2015-06-01

Previous studies on the neurocognitive impact of cannabis use have found working and declarative memory deficits that tend to normalize with abstinence. An unexplored aspect of cognitive function in chronic cannabis users is the ability to distinguish between veridical and illusory memories, a crucial aspect of reality monitoring that relies on adequate memory function and cognitive control. Using functional magnetic resonance imaging, we show that abstinent cannabis users have an increased susceptibility to false memories, failing to identify lure stimuli as events that never occurred. In addition to impaired performance, cannabis users display reduced activation in areas associated with memory processing within the lateral and medial temporal lobe (MTL), and in parietal and frontal brain regions involved in attention and performance monitoring. Furthermore, cannabis consumption was inversely correlated with MTL activity, suggesting that the drug is especially detrimental to the episodic aspects of memory. These findings indicate that cannabis users have an increased susceptibility to memory distortions even when abstinent and drug-free, suggesting a long-lasting compromise of memory and cognitive control mechanisms involved in reality monitoring.

Metamemory beliefs and episodic memory in obstructive sleep apnea syndrome.

PubMed

Daurat, Agnès; Huet, Nathalie; Tiberge, Michel

2010-08-01

This study assessed metamemory and its role in actual episodic memory performance in 26 patients with obstructive sleep apnea syndrome and 27 healthy controls. Metamemory knowledge and memory beliefs were assessed using the Metamemory Inventory in Adulthood. Episodic memory performance was investigated with the Remember/Know paradigm. Subjective sleepiness was evaluated. Patients underwent a polysomnographic assessment. In contrast to the control group's more stable memory beliefs, patients self-assessed their memory as declining across time, and felt more anxious about their memory. There was only a modest difference between patients' self-perceptions of their memory capacities and those of the control group, but patients' actual memory performance was strongly disturbed. While the latter was significantly correlated with severity of obstructive sleep apnea, scores on the Metamemory Inventory in Adulthood scales were not correlated with physiological measures, subjective sleepiness, or episodic memory performance. Obstructive sleep apnea may affect prefrontal cortex functioning and hence the ability to assess one's own memory impairment.
The Neural Representations Underlying Human Episodic Memory.

PubMed

Xue, Gui

2018-06-01

A fundamental question of human episodic memory concerns the cognitive and neural representations and processes that give rise to the neural signals of memory. By integrating behavioral tests, formal computational models, and neural measures of brain activity patterns, recent studies suggest that memory signals not only depend on the neural processes and representations during encoding and retrieval, but also on the interaction between encoding and retrieval (e.g., transfer-appropriate processing), as well as on the interaction between the tested events and all other events in the episodic memory space (e.g., global matching). In addition, memory signals are also influenced by the compatibility of the event with the existing long-term knowledge (e.g., schema matching). These studies highlight the interactive nature of human episodic memory. Copyright © 2018 Elsevier Ltd. All rights reserved.
The effect of interactions between genetics and cannabis use on neurocognition. A review.

PubMed

Cosker, E; Schwitzer, T; Ramoz, N; Ligier, F; Lalanne, L; Gorwood, P; Schwan, R; Laprévote, V

2018-03-02

Cannabis is one of the most widely-used drugs in industrialized countries. It is now well established that cannabis use impacts neurocognition. In the intoxication period time episodic memory, working memory and attention are impacted and impulsivity is increased. The long-term effects of cannabis use tend to be similar. Various internal factors, such as sex differences, modulate this impact. It is unclear whether genetic variations can also influence the impact of cannabis on neurocognition. We set out to examine the impact of genetic variations on neurocognition in cannabis users. We conducted a search via the PubMed, Web of Science, and ScienceDirect databases to identify studies measuring neurocognition and assessing genotypes in the context of cannabis use. We included 13 articles. We found that working memory, verbal and visual memory and sustained attention are more impacted during intoxication in subjects with the Val COMT allele. COMT gene could also modulate sustained attention in regular use. The CNR1, AKT1, DBH and 5-HTT/SLC6A4 genes may also modulate effects. Most of these genes are linked to schizophrenia. A fuller understanding of their impact on the effects of cannabis on neurocognition would thus help elucidate the mechanisms linking cannabis and psychosis. However, evidence is still scant, and more research is needed. Copyright © 2017. Published by Elsevier Inc.
Dopamine modulates episodic memory persistence in old age

PubMed Central

Chowdhury, Rumana; Guitart-Masip, Marc; Bunzeck, Nico; Dolan, Raymond J; Düzel, Emrah

2013-01-01

Activation of the hippocampus is required in order to encode memories for new events (or episodes). Observations from animal studies suggest that for these memories to persist beyond 4 to 6 hours, a release of dopamine generated by strong hippocampal activation is needed. This predicts that dopaminergic enhancement should improve human episodic memory persistence also for events encoded with weak hippocampal activation. Here, using pharmacological fMRI in an elderly population where there is a loss of dopamine neurons as part of normal aging, we show this very effect. The dopamine precursor levodopa led to a dose-dependent (inverted U-shape) persistent episodic memory benefit for images of scenes when tested after 6 hours, independent of whether encoding-related hippocampal fMRI activity was weak or strong (U-shaped dose-response relationship). This lasting improvement even for weakly encoded events supports a role for dopamine in human episodic memory consolidation albeit operating within a narrow dose range. PMID:23055489
Rapid Formation and Flexible Expression of Memories of Subliminal Word Pairs

PubMed Central

Reber, Thomas P.; Henke, Katharina

2011-01-01

Our daily experiences are incidentally and rapidly encoded as episodic memories. Episodic memories consist of numerous associations (e.g., who gave what to whom where and when) that can be expressed flexibly in new situations. Key features of episodic memory are speed of encoding, its associative nature, and its representational flexibility. Another defining feature of human episodic memory has been consciousness of encoding/retrieval. Here, we show that humans can rapidly form associations between subliminal words and minutes later retrieve these associations even if retrieval words were conceptually related to, but different from encoding words. Because encoding words were presented subliminally, associative encoding, and retrieval were unconscious. Unconscious association formation and retrieval were dependent on a preceding understanding of task principles. We conclude that key computations underlying episodic memory – rapid encoding and flexible expression of associations – can operate outside consciousness. PMID:22125545
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
Long-term episodic memory decline is associated with olfactory deficits only in carriers of ApoE-є4.

PubMed

Olofsson, Jonas K; Josefsson, Maria; Ekström, Ingrid; Wilson, Donald; Nyberg, Lars; Nordin, Steven; Nordin Adolfsson, Annelie; Adolfsson, Rolf; Nilsson, Lars-Göran; Larsson, Maria

2016-05-01

The ɛ4 allele of the Apolipoprotein E gene is a genetic risk factor for late-onset dementia of the Alzheimers' type (DAT), which is characterized by loss of both episodic memory and olfactory functions. Little is known about the possible role of ɛ4 in the association between ongoing episodic memory decline and olfactory deficits in the general population, but such information is relevant in determining the relevance of olfaction as a marker of DAT risk. The present study was based on a large, population-based sample (n=1087, aged 45-90 years, of which 324 were ɛ4-carriers). Episodic memory change rates were established using data collected every 5 years for a 10-20 year interval leading up to an olfactory assessment using the Scandinavian Odor Identification Test at the last wave of data collection. Participants were classified according to whether or not their episodic memory ability declined more rapidly than the age-typical norm (by >1SD). Our main result is that only in ɛ4-carriers was episodic memory decline associated with odor identification impairment. In individuals without ɛ4, odor identification was unrelated to episodic memory decline status. Follow-up analyses indicated that this moderation by ɛ4 was due to the olfactory nature of the identification test, and that the effect was not caused by 63 individuals with dementia. Our results suggest that the ɛ4 determines the functional association between ongoing episodic memory decline and olfaction. These findings are consistent with the notion that ɛ4-carriers with DAT, compared to non-carriers, display a cortical atrophy pattern that is more focused on mediotemporal lobe regions supporting olfactory and episodic memory functions. Olfactory and memory assessments might provide complementary information on mediotemporal atrophy prior to clinical dementia onset, but the ɛ4 should be considered when using olfactory assessment as an early-stage indicator. Copyright © 2016. Published by Elsevier Ltd.
One declarative memory system or two? The relationship between episodic and semantic memory in children with temporal lobe epilepsy.

PubMed

Smith, Mary Lou; Lah, Suncica

2011-09-01

This study explored verbal semantic and episodic memory in children with unilateral temporal lobe epilepsy to determine whether they had impairments in both or only 1 aspect of memory, and to examine relations between performance in the 2 domains. Sixty-six children and adolescents (37 with seizures of left temporal lobe onset, 29 with right-sided onset) were given 4 tasks assessing different aspects of semantic memory (picture naming, fluency, knowledge of facts, knowledge of word meanings) and 2 episodic memory tasks (story recall, word list recall). High rates of impairments were observed across tasks, and no differences were found related to the laterality of the seizures. Individual patient analyses showed that there was a double dissociation between the 2 aspects of memory in that some children were impaired on episodic but not semantic memory, whereas others showed intact episodic but impaired semantic memory. This double dissociation suggests that these 2 memory systems may develop independently in the context of temporal lobe pathology, perhaps related to differential effects of dysfunction in the lateral and mesial temporal lobe structures. PsycINFO Database Record (c) 2011 APA, all rights reserved.
"Truth be told" - Semantic memory as the scaffold for veridical communication.

PubMed

Hayes, Brett K; Ramanan, Siddharth; Irish, Muireann

2018-01-01

Theoretical accounts placing episodic memory as central to constructive and communicative functions neglect the role of semantic memory. We argue that the decontextualized nature of semantic schemas largely supersedes the computational bottleneck and error-prone nature of episodic memory. Rather, neuroimaging and neuropsychological evidence of episodic-semantic interactions suggest that an integrative framework more accurately captures the mechanisms underpinning social communication.
Virtual Reality as an Ecologically Valid Tool for Assessing Multifaceted Episodic Memory in Children and Adolescents

ERIC Educational Resources Information Center

Picard, Laurence; Abram, Maria; Orriols, Eric; Piolino, Pascale

2017-01-01

The majority of episodic memory (EM) tests are far removed from what we experience in daily life and from the definition of this type of memory. This study examines the developmental trajectory of the main aspects of episodic memory--what, where, and when--and of feature binding in a naturalistic virtual environment. A population of 125…
Subjective Experience of Episodic Memory and Metacognition: A Neurodevelopmental Approach

PubMed Central

Souchay, Céline; Guillery-Girard, Bérengère; Pauly-Takacs, Katalin; Wojcik, Dominika Zofia; Eustache, Francis

2013-01-01

Episodic retrieval is characterized by the subjective experience of remembering. This experience enables the co-ordination of memory retrieval processes and can be acted on metacognitively. In successful retrieval, the feeling of remembering may be accompanied by recall of important contextual information. On the other hand, when people fail (or struggle) to retrieve information, other feelings, thoughts, and information may come to mind. In this review, we examine the subjective and metacognitive basis of episodic memory function from a neurodevelopmental perspective, looking at recollection paradigms (such as source memory, and the report of recollective experience) and metacognitive paradigms such as the feeling of knowing). We start by considering healthy development, and provide a brief review of the development of episodic memory, with a particular focus on the ability of children to report first-person experiences of remembering. We then consider neurodevelopmental disorders (NDDs) such as amnesia acquired in infancy, autism, Williams syndrome, Down syndrome, or 22q11.2 deletion syndrome. This review shows that different episodic processes develop at different rates, and that across a broad set of different NDDs there are various types of episodic memory impairment, each with possibly a different character. This literature is in agreement with the idea that episodic memory is a multifaceted process. PMID:24399944
Short-term effects of glucose and sucrose on cognitive performance and mood in elderly people.

PubMed

van der Zwaluw, Nikita L; van de Rest, Ondine; Kessels, Roy P C; de Groot, Lisette C P G M

2014-01-01

In this study we determined the short-term effects of a glucose drink and a sucrose drink compared to a placebo on cognitive performance and mood in elderly people with subjective, mild memory complaints using a randomized crossover study design. In total, 43 nondiabetic older adults with self-reported memory complaints were included. Drinks consisted of 250 ml with dissolved glucose (50 g), sucrose (100 g), or a mixture of artificial sweeteners (placebo). Multiple neuropsychological tests were performed and were combined by means of z scores into four cognitive domains: episodic memory, working memory, attention and information (processing speed), and executive functioning. Mood was assessed with the short Profile of Mood Status (s-POMS) questionnaire. Blood glucose concentrations were measured at five time points to divide participants into those with a better or poorer blood glucose recovery. Performance on the domain of attention and information processing speed was significantly better after consuming the sucrose drink (domain score of 0.06, SD = 0.91) than after the placebo drink (-0.08, SD = 0.92, p = .04). Sucrose had no effect on the other three domains, and glucose had no effect on any of the domains compared to the placebo. When dividing participants into poorer or better glucose recoverers, the beneficial effect of sucrose on attention and information processing speed was only seen in participants with a poorer recovery. After sucrose consumption, depressive feelings and tension were slightly higher than after the placebo. To conclude, 100 g sucrose, but not 50 g glucose, optimized attention and information processing speed in the short term in this study in elderly people with subjective, mild memory complaints.
The optimal timing of stimulation to induce long-lasting positive effects on episodic memory in physiological aging.

PubMed

Manenti, Rosa; Sandrini, Marco; Brambilla, Michela; Cotelli, Maria

2016-09-15

Episodic memory displays the largest degree of age-related decline. A noninvasive brain stimulation technique that can be used to modulate memory in physiological aging is transcranial Direct Current Stimulation (tDCS). However, an aspect that has not been adequately investigated in previous studies is the optimal timing of stimulation to induce long-lasting positive effects on episodic memory function. Our previous studies showed episodic memory enhancement in older adults when anodal tDCS was applied over the left lateral prefrontal cortex during encoding or after memory consolidation with or without a contextual reminder. Here we directly compared the two studies to explore which of the tDCS protocols would induce longer-lasting positive effects on episodic memory function in older adults. In addition, we aimed to determine whether subjective memory complaints would be related to the changes in memory performance (forgetting) induced by tDCS, a relevant issue in aging research since individuals with subjective memory complaints seem to be at higher risk of later memory decline. The results showed that anodal tDCS applied after consolidation with a contextual reminder induced longer-lasting positive effects on episodic memory, conceivably through reconsolidation, than anodal tDCS during encoding. Furthermore, we reported, providing new data, a moderate negative correlation between subjective memory complaints and forgetting when anodal tDCS was applied after consolidation with a contextual reminder. This study sheds light on the best-suited timing of stimulation to induce long-lasting positive effects on memory function and might help the clinicians to select the most effective tDCS protocol to prevent memory decline. Copyright © 2016 Elsevier B.V. All rights reserved.
The impact of cognitive load on delayed recall.

PubMed

Camos, Valérie; Portrat, Sophie

2015-08-01

Recent studies have suggested that long-term retention of items studied in a working memory span task depends on the refreshing of memory items-more specifically, on the number of refreshing opportunities. However, it was previously shown that refreshing depends on the cognitive load of the concurrent task introduced in the working memory span task. Thus, cognitive load should determine the long-term retention of items assessed in a delayed-recall test if such retention relies on refreshing. In two experiments, while the amount of refreshing opportunities remained constant, we varied the cognitive load of the concurrent task by either introducing tasks differing in their attentional demands or varying the pace of the concurrent task. To verify that this effect was related to refreshing and not to any maintenance mechanism, we also manipulated the availability of subvocal rehearsal. Replicating previous results, increasing cognitive load reduced immediate recall. This increase also had a detrimental effect on delayed recall. Conversely, the addition of concurrent articulation reduced immediate but not delayed recall. This study shows that both working and episodic memory traces depend on the cognitive load of the concurrent task, whereas the use of rehearsal affects only working memory performance. These findings add further evidence of the dissociation between subvocal rehearsal and attentional refreshing.
Robust memory of where from way back when: evidence from behaviour and visual attention.

PubMed

Bauer, Patricia J; Stewart, Rebekah; Sirkin, Ruth E; Larkina, Marina

2017-09-01

Retention of events typically exhibits a sharp initial decrease followed by levelling off of forgetting. In an apparent exception to this general rule, college students have robust memory for their own locations in obscured versions of photographs of their entering classes taken during orientation-related activities, whether tested 2 months or 42 months after the event. Experiment 1 of the present research was a test for conceptual replication of this finding in photographs depicting more than twice the number of students (and thus potential distracters). There was no difference in memory accuracy for personal spatial location across retention intervals of 6-30 months. Experiment 2 featured 40-h and 2-month retention intervals, thereby providing a more fine-grained test of the forgetting function. The findings replicated Experiment 1. In Experiment 3, eye-tracking measures of visual attention revealed that participants rapidly fixated their own spatial locations within the photographs, even in the absence of explicit awareness. In all three experiments, memory for temporal features of the orientation activities (e.g., day and time the photograph was taken) followed the typical forgetting function. The findings suggest differential preservation of episodic memory for where relative to other aspects of events and experiences, such as when.
Thalamic structures and associated cognitive functions: Relations with age and aging.

PubMed

Fama, Rosemary; Sullivan, Edith V

2015-07-01

The thalamus, with its cortical, subcortical, and cerebellar connections, is a critical node in networks supporting cognitive functions known to decline in normal aging, including component processes of memory and executive functions of attention and information processing. The macrostructure, microstructure, and neural connectivity of the thalamus changes across the adult lifespan. Structural and functional magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) have demonstrated, regional thalamic volume shrinkage and microstructural degradation, with anterior regions generally more compromised than posterior regions. The integrity of selective thalamic nuclei and projections decline with advancing age, particularly those in thalamofrontal, thalamoparietal, and thalamolimbic networks. This review presents studies that assess the relations between age and aging and the structure, function, and connectivity of the thalamus and associated neural networks and focuses on their relations with processes of attention, speed of information processing, and working and episodic memory. Copyright © 2015 Elsevier Ltd. All rights reserved.
Amygdala activity at encoding corresponds with memory vividness and with memory for select episodic details.

PubMed

Kensinger, Elizabeth A; Addis, Donna Rose; Atapattu, Ranga K

2011-03-01

It is well known that amygdala activity during encoding corresponds with subsequent memory for emotional information. It is less clear how amygdala activity relates to the subjective and objective qualities of a memory. In the present study, participants viewed emotional and neutral objects while undergoing a functional magnetic resonance imaging scan. Participants then took a memory test, identifying which verbal labels named a studied object and indicating the vividness of their memory for that object. They then retrieved episodic details associated with each object's presentation, selecting which object exemplar had been studied and indicating in which screen quadrant, study list, and with which encoding question the exemplar had been studied. Parametric analysis of the encoding data allowed examination of the processes that tracked with increasing memory vividness or with an increase in the diversity of episodic details remembered. Dissociable networks tracked these two increases, and amygdala activity corresponded with the former but not the latter. Subsequent-memory analyses revealed that amygdala activity corresponded with memory for exemplar type but not for other episodic features. These results emphasize that amygdala activity does not ensure accurate encoding of all types of episodic detail, yet it does support encoding of some item-specific details and leads to the retention of a memory that will feel subjectively vivid. The types of episodic details tied to amygdala engagement may be those that are most important for creating a subjectively vivid memory. Copyright © 2011 Elsevier Ltd. All rights reserved.
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.
Amygdala Activity at Encoding Corresponds with Memory Vividness and with Memory for Select Episodic Details

PubMed Central

Kensinger, Elizabeth A.; Addis, Donna Rose; Atapattu, Ranga K.

2011-01-01

It is well known that amygdala activity during encoding corresponds with subsequent memory for emotional information. It is less clear how amygdala activity relates to the subjective and objective qualities of a memory. In the present study, participants viewed emotional and neutral objects while undergoing a functional magnetic resonance imaging scan. Participants then took a memory test, identifying which verbal labels named a studied object and indicating the vividness of their memory for that object. They then retrieved episodic details associated with each object’s presentation, selecting which object exemplar had been studied and indicating in which screen quadrant, study list, and with which encoding question the exemplar had been studied. Parametric analysis of the encoding data allowed examination of the processes that tracked with increasing memory vividness or with an increase in the diversity of episodic details remembered. Dissociable networks tracked these two increases, and amygdala activity corresponded with the former but not the latter. Subsequent-memory analyses revealed that amygdala activity corresponded with memory for exemplar type but not for other episodic features. These results emphasize that amygdala activity does not ensure accurate encoding of all types of episodic detail, yet it does support encoding of some item-specific details and leads to the retention of a memory that will feel subjectively vivid. The types of episodic details tied to amygdala engagement may be those that are most important for creating a subjectively vivid memory. PMID:21262244
Episodic future thinking and episodic counterfactual thinking: intersections between memory and decisions.

PubMed

Schacter, Daniel L; Benoit, Roland G; De Brigard, Felipe; Szpunar, Karl K

2015-01-01

This article considers two recent lines of research concerned with the construction of imagined or simulated events that can provide insight into the relationship between memory and decision making. One line of research concerns episodic future thinking, which involves simulating episodes that might occur in one's personal future, and the other concerns episodic counterfactual thinking, which involves simulating episodes that could have happened in one's personal past. We first review neuroimaging studies that have examined the neural underpinnings of episodic future thinking and episodic counterfactual thinking. We argue that these studies have revealed that the two forms of episodic simulation engage a common core network including medial parietal, prefrontal, and temporal regions that also supports episodic memory. We also note that neuroimaging studies have documented neural differences between episodic future thinking and episodic counterfactual thinking, including differences in hippocampal responses. We next consider behavioral studies that have delineated both similarities and differences between the two kinds of episodic simulation. The evidence indicates that episodic future and counterfactual thinking are characterized by similarly reduced levels of specific detail compared with episodic memory, but that the effects of repeatedly imagining a possible experience have sharply contrasting effects on the perceived plausibility of those events during episodic future thinking versus episodic counterfactual thinking. Finally, we conclude by discussing the functional consequences of future and counterfactual simulations for decisions. Copyright © 2013 Elsevier Inc. All rights reserved.

Episodic future thinking and episodic counterfactual thinking: Intersections between memory and decisions

PubMed Central

Schacter, Daniel L.; Benoit, Roland G.; De Brigard, Felipe; Szpunar, Karl K.

2014-01-01

This article considers two recent lines of research concerned with the construction of imagined or simulated events that can provide insight into the relationship between memory and decision making. One line of research concerns episodic future thinking, which involves simulating episodes that might occur in one’s personal future, and the other concerns episodic counterfactual thinking, which involves simulating episodes that could have happened in one’s personal past. We first review neuroimaging studies that have examined the neural underpinnings of episodic future thinking and episodic counterfactual thinking. We argue that these studies have revealed that the two forms of episodic simulation engage a common core network including medial parietal, prefrontal, and temporal regions that also supports episodic memory. We also note that neuroimaging studies have documented neural differences between episodic future thinking and episodic counterfactual thinking, including differences in hippocampal responses. We next consider behavioral studies that have delineated both similarities and differences between the two kinds of episodic simulation. The evidence indicates that episodic future and counterfactual thinking are characterized by similarly reduced levels of specific detail compared with episodic memory, but that the effects of repeatedly imagining a possible experience have sharply contrasting effects on the perceived plausibility of those events during episodic future thinking versus episodic counterfactual thinking. Finally, we conclude by discussing the functional consequences of future and counterfactual simulations for decisions. PMID:24373942
Contributions of Feature Binding During Encoding and Functional Connectivity of the Medial Temporal Lobe Structures to Episodic Memory Deficits Across the Prodromal and First-Episode Phases of Schizophrenia

PubMed Central

Haut, Kristen M.; van Erp, Theo G. M.; Knowlton, Barbara; Bearden, Carrie E.; Subotnik, Kenneth; Ventura, Joseph; Nuechterlein, Keith H.; Cannon, Tyrone D.

2014-01-01

Patients with and at risk for psychosis may have difficulty using associative strategies to facilitate episodic memory encoding and recall. In parallel studies, patients with first-episode schizophrenia (n = 27) and high psychosis risk (n = 28) compared with control participants (n = 22 and n = 20, respectively) underwent functional MRI during a remember-know memory task. Psychophysiological interaction analyses, using medial temporal lobe (MTL) structures as regions of interest, were conducted to measure functional connectivity patterns supporting successful episodic memory. During encoding, patients with first-episode schizophrenia demonstrated reduced functional coupling between MTL regions and regions involved in stimulus representations, stimulus selection, and cognitive control. Relative to control participants and patients with high psychosis risk who did not convert to psychosis, patients with high psychosis risk who later converted to psychosis also demonstrated reduced connectivity between MTL regions and auditory-verbal and visual-association regions. These results suggest that episodic memory deficits in schizophrenia are related to inefficient recruitment of cortical connections involved in associative memory formation; such deficits precede the onset of psychosis among those individuals at high clinical risk. PMID:25750836
Contributions of Feature Binding During Encoding and Functional Connectivity of the Medial Temporal Lobe Structures to Episodic Memory Deficits Across the Prodromal and First-Episode Phases of Schizophrenia.

PubMed

Haut, Kristen M; van Erp, Theo G M; Knowlton, Barbara; Bearden, Carrie E; Subotnik, Kenneth; Ventura, Joseph; Nuechterlein, Keith H; Cannon, Tyrone D

2015-03-01

Patients with and at risk for psychosis may have difficulty using associative strategies to facilitate episodic memory encoding and recall. In parallel studies, patients with first-episode schizophrenia ( n = 27) and high psychosis risk ( n = 28) compared with control participants ( n = 22 and n = 20, respectively) underwent functional MRI during a remember-know memory task. Psychophysiological interaction analyses, using medial temporal lobe (MTL) structures as regions of interest, were conducted to measure functional connectivity patterns supporting successful episodic memory. During encoding, patients with first-episode schizophrenia demonstrated reduced functional coupling between MTL regions and regions involved in stimulus representations, stimulus selection, and cognitive control. Relative to control participants and patients with high psychosis risk who did not convert to psychosis, patients with high psychosis risk who later converted to psychosis also demonstrated reduced connectivity between MTL regions and auditory-verbal and visual-association regions. These results suggest that episodic memory deficits in schizophrenia are related to inefficient recruitment of cortical connections involved in associative memory formation; such deficits precede the onset of psychosis among those individuals at high clinical risk.
Dynamic switching between semantic and episodic memory systems.

PubMed

Kompus, Kristiina; Olsson, Carl-Johan; Larsson, Anne; Nyberg, Lars

2009-09-01

It has been suggested that episodic and semantic long-term memory systems interact during retrieval. Here we examined the flexibility of memory retrieval in an associative task taxing memories of different strength, assumed to differentially engage episodic and semantic memory. Healthy volunteers were pre-trained on a set of 36 face-name pairs over a 6-week period. Another set of 36 items was shown only once during the same time period. About 3 months after the training period all items were presented in a randomly intermixed order in an event-related fMRI study of face-name memory. Once presented items differentially activated anterior cingulate cortex and a right prefrontal region that previously have been associated with episodic retrieval mode. High-familiar items were associated with stronger activation of posterior cortices and a left frontal region. These findings fit a model of memory retrieval by which early processes determine, on a trial-by-trial basis, if the task can be solved by the default semantic system. If not, there is a dynamic shift to cognitive control processes that guide retrieval from episodic memory.
Ageing-related stereotypes in memory: When the beliefs come true.

PubMed

Bouazzaoui, Badiâa; Follenfant, Alice; Ric, François; Fay, Séverine; Croizet, Jean-Claude; Atzeni, Thierry; Taconnat, Laurence

2016-01-01

Age-related stereotype concerns culturally shared beliefs about the inevitable decline of memory with age. In this study, stereotype priming and stereotype threat manipulations were used to explore the impact of age-related stereotype on metamemory beliefs and episodic memory performance. Ninety-two older participants who reported the same perceived memory functioning were divided into two groups: a threatened group and a non-threatened group (control). First, the threatened group was primed with an ageing stereotype questionnaire. Then, both groups were administered memory complaints and memory self-efficacy questionnaires to measure metamemory beliefs. Finally, both groups were administered the Logical Memory task to measure episodic memory, for the threatened group the instructions were manipulated to enhance the stereotype threat. Results indicated that the threatened individuals reported more memory complaints and less memory efficacy, and had lower scores than the control group on the logical memory task. A multiple mediation analysis revealed that the stereotype threat effect on the episodic memory performance was mediated by both memory complaints and memory self-efficacy. This study revealed that stereotype threat impacts belief in one's own memory functioning, which in turn impairs episodic memory performance.
Episodic foresight deficits in regular, but not recreational, cannabis users.

PubMed

Mercuri, Kimberly; Terrett, Gill; Henry, Julie D; Curran, H Valerie; Elliott, Morgan; Rendell, Peter G

2018-06-01

Cannabis use is associated with a range of neurocognitive deficits, including impaired episodic memory. However, no study to date has assessed whether these difficulties extend to episodic foresight, a core component of which is the ability to mentally travel into one's personal future. This is a particularly surprising omission given that episodic memory is considered to be critical to engage episodic foresight. In the present study, we provide the first test of how episodic foresight is affected in the context of differing levels of cannabis use, and the degree to which performance on a measure of this construct is related to episodic memory. Fifty-seven regular cannabis users (23 recreational, 34 regular) and 57 controls were assessed using an adapted version of the Autobiographical Interview. The results showed that regular-users exhibited greater impairment of episodic foresight and episodic memory than both recreational-users and cannabis-naïve controls. These data therefore show for the first time that cannabis-related disruption of cognitive functioning extends to the capacity for episodic foresight, and they are discussed in relation to their potential implications for functional outcomes in this group.
Generalized dissociative amnesia: episodic, semantic and procedural memories lost and found.

PubMed

van der Hart, O; Nijenhuis, E

2001-10-01

This review tests Ribot's classic twofold categorization of generalized amnesia (GA) into Type I, total loss of episodic memory, and Type II, additional more or less extensive loss of semantic and/or procedural memory. It also explores his law of regression, according to which, cast in modern terms, recovery of lost procedural and semantic memories precedes recovery of episodic memory, as well as reported aetiological factors. Clinically and formally assessed cases of GA, published since 1845, were surveyed and further analysed. Over and above authentic episodic memory loss, cases differed widely in the extent of impairment of semantic and procedural memory. Recovery of semantic and procedural memory often preceded recovery of episodic memory. This particularly applied to authenticated trauma memories. To an extent, lost memories affected current functioning, and in some cases were associated with alternating dissociative personalities. Severe memory distortions upon memory recovery were not reported. Most cases were trauma or stress related, while in some cases the aetiology remained unknown. Contrary to the view expressed in DSM-IV, which states that dissociative amnesia pertains to an inability to recall personal information, GA may also involve loss and recovery of semantic and procedural memories. Since the loss of various memory types in GA is dimensional rather than categorical, Ribot's typological distinction does not hold. Some of the reviewed cases suggest a trauma-related aetiology. Generalized amnesia of varying degrees of severity can involve delayed retrieval of trauma memories, as well as the loss and delayed retrieval of the premorbid personality.
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.
Integrative Review of the Relationship Between Sleep Disturbances and Episodic Memory in Older Adults.

PubMed

Yeh, An-Yun; Pressler, Susan J; Giordani, Bruno J; Pozehl, Bunny J; Berger, Ann M

2018-07-01

Impaired episodic memory in older adults has been linked to many factors. One of these factors is sleep disturbances, which are reported by more than 50% of older adults. The relationship between episodic memory and sleep disturbances remains unclear, however, because of the multiple types of measures of sleep and episodic memory used in previous studies. The purpose of this integrative literature review was to integrate and compare findings on this relationship in adults aged 65 years. An electronic search was conducted in PubMed, Cumulative Index to Nursing and Allied Health Literature, PsychINFO, and Medline for material published from the inception of the databases to December 2016. The literature search produced 13 data-based, peer-reviewed, and primary research articles that met eligibility criteria. The synthesized results from these articles provide evidence that older adults with 6-8 hr of self-reported total sleep time had better episodic memory than older adults with ≤5 hr or ≥9 hr of total sleep time. Shorter length and lower percentage of slow-wave sleep were associated with reduced episodic memory in older adults, but the results were controversial. Selection of different measurements and inconsistent variables across studies increased the difficulty of synthesizing and comparing the results. The diversity of covariates controlled in the included articles raise questions regarding which covariates should be controlled in such studies of sleep and episodic memory in older adults. The numerous study limitations were thus major barriers to understanding the relationship between sleep disturbances and episodic memory.
Spatial Navigation Impairments Among Intellectually High-Functioning Adults With Autism Spectrum Disorder: Exploring Relations With Theory of Mind, Episodic Memory, and Episodic Future Thinking

PubMed Central

2013-01-01

Research suggests that spatial navigation relies on the same neural network as episodic memory, episodic future thinking, and theory of mind (ToM). Such findings have stimulated theories (e.g., the scene construction and self-projection hypotheses) concerning possible common underlying cognitive capacities. Consistent with such theories, autism spectrum disorder (ASD) is characterized by concurrent impairments in episodic memory, episodic future thinking, and ToM. However, it is currently unclear whether spatial navigation is also impaired. Hence, ASD provides a test case for the scene construction and self-projection theories. The study of spatial navigation in ASD also provides a test of the extreme male brain theory of ASD, which predicts intact or superior navigation (purportedly a systemizing skill) performance among individuals with ASD. Thus, the aim of the current study was to establish whether spatial navigation in ASD is impaired, intact, or superior. Twenty-seven intellectually high-functioning adults with ASD and 28 sex-, age-, and IQ-matched neurotypical comparison adults completed the memory island virtual navigation task. Tests of episodic memory, episodic future thinking, and ToM were also completed. Participants with ASD showed significantly diminished performance on the memory island task, and performance was positively related to ToM and episodic memory, but not episodic future thinking. These results suggest that (contra the extreme male brain theory) individuals with ASD have impaired survey-based navigation skills—that is, difficulties generating cognitive maps of the environment—and adds weight to the idea that scene construction/self-projection are impaired in ASD. The theoretical and clinical implications of these results are discussed. PMID:24364620
Altered Effective Connectivity of Hippocampus-Dependent Episodic Memory Network in mTBI Survivors

PubMed Central

2016-01-01

Traumatic brain injuries (TBIs) are generally recognized to affect episodic memory. However, less is known regarding how external force altered the way functionally connected brain structures of the episodic memory system interact. To address this issue, we adopted an effective connectivity based analysis, namely, multivariate Granger causality approach, to explore causal interactions within the brain network of interest. Results presented that TBI induced increased bilateral and decreased ipsilateral effective connectivity in the episodic memory network in comparison with that of normal controls. Moreover, the left anterior superior temporal gyrus (aSTG, the concept forming hub), left hippocampus (the personal experience binding hub), and left parahippocampal gyrus (the contextual association hub) were no longer network hubs in TBI survivors, who compensated for hippocampal deficits by relying more on the right hippocampus (underlying perceptual memory) and the right medial frontal gyrus (MeFG) in the anterior prefrontal cortex (PFC). We postulated that the overrecruitment of the right anterior PFC caused dysfunction of the strategic component of episodic memory, which caused deteriorating episodic memory in mTBI survivors. Our findings also suggested that the pattern of brain network changes in TBI survivors presented similar functional consequences to normal aging. PMID:28074162
Episodic-like memory in the rat.

PubMed

Babb, Stephanie J; Crystal, Jonathon D

2006-07-11

A fundamental question in comparative cognition is whether animals remember unique, personal past experiences. It has long been argued that memories for specific events (referred to as episodic memory) are unique to humans. Recently, considerable evidence has accumulated to show that food-storing birds possess critical behavioral elements of episodic memory, referred to as episodic-like memory in acknowledgment of the fact that behavioral criteria do not assess subjective experiences. Here we show that rats have a detailed representation of remembered events and meet behavioral criteria for episodic-like memory. We provided rats with access to locations baited with distinctive (e.g., grape and raspberry) or nondistinctive (regular chow) flavors. Locations with a distinctive flavor replenished after a long but not a short delay, and locations with the nondistinctive flavor never replenished. One distinctive flavor was devalued after encoding its location by prefeeding that flavor (satiation) or by pairing it with lithium chloride (acquired taste aversion), while the other distinctive flavor was not devalued. The rats selectively decreased revisits to the devalued distinctive flavor but not to the nondevalued distinctive flavor. The present studies demonstrate that rats selectively encode the content of episodic-like memories.
Impact of Cognitive Architectures on Human-Computer Interaction

DTIC Science & Technology

2014-09-01

activation, reinforced learning, emotion, semantic memory , episodic memory , and visual imagery.12 In 2010 Rosenbloom created a variant of the Soar...being added to almost every new version. In 2004 Nuxoll and Laird added episodic memory to the Soar architecture.11 In 2008 Laird presented...York (NY): Psychology Press; 2014; p. 1–50. 11. Nuxoll A, Laird JE. A cognitive model of episodic memory integrated with a general cognitive
A Long-Term Retention Advantage for Spatial Information Learned Naturally and in the Laboratory

DTIC Science & Technology

1989-06-09

study. Memory & Cognition, 10, 324-332. Tulving, E. (1972). Episodic and semantic memory . In E. Tulving & W. Donaldson (Eds.), Organization of memory ...the cognitive research literature. Some of the better known divisions include the distinction between semantic , episodic and procedural knowledge...the probe method by being more structured and more focused on specific memory episodes . In general, questionnaire studies simply involve formulating
Unaware Memory in Hypothesis Generation Tasks

DTIC Science & Technology

1986-12-01

have been offered within the context of Tulving’s (1972) distinction between episodic and semantic memory systems (e.g., see Jacoby & - Witherspoon...in this direction (see Tulving, 1985) raise the possibility that neither episodic nor semantic memory systems can account for the type of unaware...material: Interactions with " episodic " and " semantic " memory . Conitive Psycholozv, 12, 227-251. Kolers, P. A. (1976). Reading a year later. Journal o
Imagining the future: The core episodic simulation network dissociates as a function of timecourse and the amount of simulated information

PubMed Central

Thakral, Preston P.; Benoit, Roland G.; Schacter, Daniel L.

2017-01-01

Neuroimaging data indicate that episodic memory (i.e., remembering specific past experiences) and episodic simulation (i.e., imagining specific future experiences) are associated with enhanced activity in a common set of neural regions, often referred to as the core network. This network comprises the hippocampus, parahippocampal cortex, lateral and medial parietal cortex, lateral temporal cortex, and medial prefrontal cortex. Evidence for a core network has been taken as support for the idea that episodic memory and episodic simulation are supported by common processes. Much remains to be learned about how specific core network regions contribute to specific aspects of episodic simulation. Prior neuroimaging studies of episodic memory indicate that certain regions within the core network are differentially sensitive to the amount of information recollected (e.g., the left lateral parietal cortex). In addition, certain core network regions dissociate as a function of their timecourse of engagement during episodic memory (e.g., transient activity in the posterior hippocampus and sustained activity in the left lateral parietal cortex). In the current study, we assessed whether similar dissociations could be observed during episodic simulation. We found that the left lateral parietal cortex modulates as a function of the amount of simulated details. Of particular interest, while the hippocampus was insensitive to the amount of simulated details, we observed a temporal dissociation within the hippocampus: transient activity occurred in relatively posterior portions of the hippocampus and sustained activity occurred in anterior portions. Because the posterior hippocampal and lateral parietal findings parallel those observed previously during episodic memory, the present results add to the evidence that episodic memory and episodic simulation are supported by common processes. Critically, the present study also provides evidence that regions within the core network support dissociable processes. PMID:28324695
Cognitive Control of Eating: the Role of Memory in Appetite and Weight Gain.

PubMed

Higgs, Suzanne; Spetter, Maartje S

2018-03-01

The present review organises the recent literature on the role of memory in eating behaviours and provides an overview of the current evidence relating to the associations between memory and weight gain. Research over the last few years has highlighted working memory as an important cognitive process that underpins many aspects of appetite control. Recent work on episodic memory and appetite has replicated work showing that manipulating memory for recent eating affects later consumption and extended this work to examine associations between individual differences in memory and eating behaviours. Poorer episodic memory ability is related to a reduced sensitivity to internal states of hunger and satiety and a tendency towards uncontrolled eating. There is also recent evidence to suggest that working memory and episodic memory impairments are related to weight gain and high BMI. Working memory and episodic memory are core cognitive processes that are critical for food-related decision-making, and disruption to these processes contributes to problems with appetite control and weight gain, which suggests that weight loss programmes might be improved by the addition of cognitive training.
The influence of levels of processing on recall from working memory and delayed recall tasks.

PubMed

Loaiza, Vanessa M; McCabe, David P; Youngblood, Jessie L; Rose, Nathan S; Myerson, Joel

2011-09-01

Recent research in working memory has highlighted the similarities involved in retrieval from complex span tasks and episodic memory tasks, suggesting that these tasks are influenced by similar memory processes. In the present article, the authors manipulated the level of processing engaged when studying to-be-remembered words during a reading span task (Experiment 1) and an operation span task (Experiment 2) in order to assess the role of retrieval from secondary memory during complex span tasks. Immediate recall from both span tasks was greater for items studied under deep processing instructions compared with items studied under shallow processing instructions regardless of trial length. Recall was better for deep than for shallow levels of processing on delayed recall tests as well. These data are consistent with the primary-secondary memory framework, which suggests that to-be-remembered items are displaced from primary memory (i.e., the focus of attention) during the processing phases of complex span tasks and therefore must be retrieved from secondary memory. (c) 2011 APA, all rights reserved.
Deficits in episodic memory are related to uncontrolled eating in a sample of healthy adults.

PubMed

Martin, A A; Davidson, T L; McCrory, M A

2018-05-01

Despite a substantial amount of animal data linking deficits in memory inhibition to the development of overeating and obesity, few studies have investigated the relevance of memory inhibition to uncontrolled eating in humans. Further, although memory for recent eating has been implicated as an important contributor to satiety and energy intake, the possibility that variations in episodic memory relate to individual differences in food intake control has been largely neglected. To examine these relationships, we recruited ninety-three adult subjects to attend a single lab session where we assessed body composition, dietary intake, memory performance, and eating behaviors (Three Factor Eating Questionnaire). Episodic recall and memory inhibition were assessed using a well-established measure of memory interference (Retrieval Practice Paradigm). Hierarchical regression analyses indicated that memory inhibition was largely unrelated to participants' eating behaviors; however, episodic recall was reliably predicted by restrained vs. uncontrolled eating: recall was positively associated with strategic dieting (β = 2.45, p = 0.02), avoidance of fatty foods (β = 3.41, p = 0.004), and cognitive restraint (β = 1.55, p = 0.04). In contrast, recall was negatively associated with uncontrolled eating (β = -1.15, p = 0.03) and emotional eating (β = -2.46, p = 0.04). These findings suggest that episodic memory processing is related to uncontrolled eating in humans. The possibility that deficits in episodic memory may contribute to uncontrolled eating by disrupting memory for recent eating is discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.
Episodic and Semantic Memory Influences on Picture Naming in Alzheimer's Disease

ERIC Educational Resources Information Center

Small, Jeff A.; Sandhu, Nirmaljeet

2008-01-01

This study investigated the relationship between semantic and episodic memory as they support lexical access by healthy younger and older adults and individuals with Alzheimer's disease (AD). In particular, we were interested in examining the pattern of semantic and episodic memory declines in AD (i.e., word-finding difficulty and impaired recent…

Episodic memory and the witness trump card.

PubMed

Henry, Jeremy; Craver, Carl

2018-01-01

We accept Mahr & Csibra's (M&C's) causal claim that episodic memory provides humans with the means for evaluating the veracity of reports about non-occurrent events. We reject their evolutionary argument that this is the proper function of episodic memory. We explore three intriguing implications of the causal claim, for cognitive neuropsychology, comparative psychology, and philosophy.
Episodic Memory: Manipulation and Replay of Episodic Memories by Rats.

PubMed

Wright, Anthony A

2018-06-04

Rats exposed to variable-length, unique-odor lists were tested in distinctive contexts for odors second or forth from list-end. Accurate ability to recall odors backwards from the end of lists points to their ability to manipulate and replay odor-list episodic memories. Copyright © 2018 Elsevier Ltd. 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

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.
Episodic but not semantic order memory difficulties in autism spectrum disorder: evidence from the Historical Figures Task.

PubMed

Gaigg, Sebastian B; Bowler, Dermot M; Gardiner, John M

2014-01-01

Considerable evidence suggests that the episodic memory system operates abnormally in autism spectrum disorder (ASD) whereas the functions of the semantic memory system are relatively preserved. Here we show that the same dissociation also applies to the domain of order memory. We asked adult participants to order the names of famous historical figures either according to their chronological order in history (probing semantic memory) or according to a random sequence shown once on a screen (probing episodic memory). As predicted, adults with ASD performed less well than age- and IQ-matched comparison individuals only on the episodic task. This observation is of considerable importance in the context of developmental theory because semantic and episodic order memory abilities can be dissociated in typically developing infants before they reach the age at which the behavioural markers associated with ASD are first apparent. This raises the possibility that early emerging memory abnormalities play a role in shaping the developmental trajectory of the disorder. We discuss the broader implications of this possibility and highlight the urgent need for greater scrutiny of memory competences in ASD early in development.
Age Invariance in Semantic and Episodic Metamemory: Both Younger and Older Adults Provide Accurate Feeling of Knowing For Names of Faces

PubMed Central

Eakin, Deborah K.; Hertzog, Christopher; Harris, William

2013-01-01

Age differences in feeling-of-knowing (FOK) accuracy were examined for both episodic memory and semantic memory. Younger and older adults either viewed pictures of famous faces (semantic memory) or associated nonfamous faces and names (episodic memory) and were tested on their memory for the name of the presented face. Participants viewed the faces again and made a FOK prediction about future recognition of the name associated with the presented face. Finally, four-alternative forced-choice recognition memory for the name, cued by the face, was tested and confidence judgments (CJs) were collected for each recognition response. Age differences were not obtained in semantic memory or the resolution of semantic FOKs, defined by within-person correlations of FOKs with recognition memory performance. Although age differences were obtained in level of episodic memory, there were no age differences in the resolution of episodic FOKs. FOKs for correctly recognized items correlated reliably with CJs for both types of materials, and did not differ by age group. The results indicate age invariance in monitoring of retrieval processes for name-face associations. PMID:23537379
Age invariance in semantic and episodic metamemory: both younger and older adults provide accurate feeling-of-knowing for names of faces.

PubMed

Eakin, Deborah K; Hertzog, Christopher; Harris, William

2014-01-01

Age differences in feeling-of-knowing (FOK) accuracy were examined for both episodic memory and semantic memory. Younger and older adults either viewed pictures of famous faces (semantic memory) or associated non-famous faces and names (episodic memory) and were tested on their memory for the name of the presented face. Participants viewed the faces again and made a FOK prediction about future recognition of the name associated with the presented face. Finally, four-alternative forced-choice recognition memory for the name, cued by the face, was tested and confidence judgments (CJs) were collected for each recognition response. Age differences were not obtained in semantic memory or the resolution of semantic FOKs, defined by within-person correlations of FOKs with recognition memory performance. Although age differences were obtained in level of episodic memory, there were no age differences in the resolution of episodic FOKs. FOKs for correctly recognized items correlated reliably with CJs for both types of materials, and did not differ by age group. The results indicate age invariance in monitoring of retrieval processes for name-face associations.
Interaction between the medial prefrontal cortex and hippocampal CA1 area is essential for episodic-like memory in rats.

PubMed

Chao, Owen Y; Nikolaus, Susanne; Lira Brandão, Marcus; Huston, Joseph P; de Souza Silva, Maria A

2017-05-01

The interplay between medial prefrontal cortex (mPFC) and hippocampus, particularly the hippocampal CA3 area, is critical for episodic memory. To what extent the mPFC also interacts with the hippocampus CA1 subregion still requires elucidation. To investigate this issue, male rats received unilateral N-methyl- D -aspartate lesions of the mPFC together with unilateral lesions of the hippocampal CA1 area, either in the same (control) or in the opposite hemispheres (disconnection). They underwent an episodic-like memory test, combining what-where-when information, and separate tests for novel object preference (what), object place preference (where) and temporal order memory (when). Compared to controls, the disconnected mPFC-CA1 rats exhibited disrupted episodic-like memory with an impaired integration of the what-where-when elements. Both groups showed intact memories for what and when, while only the control group showed intact memory for where. These findings suggest that the functional interaction of the mPFC-CA1 circuit is crucial for the processing of episodic memory and, in particular, for the integration of the spatial memory component. Copyright © 2017 Elsevier Inc. All rights reserved.
Supporting the self-concept with memory: insight from amnesia

PubMed Central

Verfaellie, Mieke

2015-01-01

We investigated the extent to which personal semantic memory supports the self-concept in individuals with medial temporal lobe amnesia and healthy adults. Participants completed eight ‘I Am’ self-statements. For each of the four highest ranked self-statements, participants completed an open-ended narrative task, during which they provided supporting information indicating why the I Am statement was considered self-descriptive. Participants then completed an episodic probe task, during which they attempted to retrieve six episodic memories for each of these self-statements. Supporting information was scored as episodic, personal semantic or general semantic. In the narrative task, personal semantic memory predominated as self-supporting information in both groups. The amnesic participants generated fewer personal semantic memories than controls to support their self-statements, a deficit that was more pronounced for trait relative to role self-statements. In the episodic probe task, the controls primarily generated unique event memories, but the amnesic participants did not. These findings demonstrate that personal semantic memory, in particular autobiographical fact knowledge, plays a critical role in supporting the self-concept, regardless of the accessibility of episodic memories, and they highlight potential differences in the way traits and roles are supported by personal memory. PMID:25964501
How autobiographical memories can support episodic recall: transfer and maintenance effect of memory training with old-old low-autonomy adults.

PubMed

Carretti, Barbara; Facchini, Giulia; Nicolini, Chiara

2011-02-01

A large body of research has demonstrated that, although specific memory activities can enhance the memory performance of healthy older adults, the extent of the increment is negatively associated with age. Conversely, few studies have examined the case of healthy elderly people not living alone. This study has two mains goals: to understand whether older adults with limited autonomy can benefit from activities devoted to increasing their episodic memory performance, and to test the efficacy of a memory training program based on autobiographical memories, in terms of transfer and maintenance effect. We postulated that being able to rely on stable autobiographical memories (intrinsically associated with emotions) would be a valuable memory aid. Memory training was given to healthy older adults (aged 75-85) living in a retirement home. Two programs were compared: in the first, participants were primed to recall autobiographical memories around certain themes, and then to complete a set of episodic memory tasks (experimental group); in the second, participants were only given the episodic tasks (control group). Both groups improved their performance from pre- to post-test. However, the experimental group reported a greater feeling of well-being after the training, and maintained the training gains relating to episodic performance after three months. Our findings suggest that specific memory activities are beneficial to elderly people living in a retirement home context. In addition, training based on reactivation of autobiographical memories is shown to produce a long-lasting effect on memory performance.
Experimental Effects of Acute Exercise on Iconic Memory, Short-Term Episodic, and Long-Term Episodic Memory.

PubMed

Yanes, Danielle; Loprinzi, Paul D

2018-06-11

The present experiment evaluated the effects of acute exercise on iconic memory and short- and long-term episodic memory. A two-arm, parallel-group randomized experiment was employed ( n = 20 per group; M age = 21 year). The experimental group engaged in an acute bout of moderate-intensity treadmill exercise for 15 min, while the control group engaged in a seated, time-matched computer task. Afterwards, the participants engaged in a paragraph-level episodic memory task (20 min delay and 24 h delay recall) as well as an iconic memory task, which involved 10 trials (at various speeds from 100 ms to 800 ms) of recalling letters from a 3 × 3 array matrix. For iconic memory, there was a significant main effect for time (F = 42.9, p < 0.001, η² p = 0.53) and a trend towards a group × time interaction (F = 2.90, p = 0.09, η² p = 0.07), but no main effect for group (F = 0.82, p = 0.37, η² p = 0.02). The experimental group had higher episodic memory scores at both the baseline (19.22 vs. 17.20) and follow-up (18.15 vs. 15.77), but these results were not statistically significant. These findings provide some suggestive evidence hinting towards an iconic memory and episodic benefit from acute exercise engagement.
Functional connectivity of hippocampal and prefrontal networks during episodic and spatial memory based on real-world environments.

PubMed

Robin, Jessica; Hirshhorn, Marnie; Rosenbaum, R Shayna; Winocur, Gordon; Moscovitch, Morris; Grady, Cheryl L

2015-01-01

Several recent studies have compared episodic and spatial memory in neuroimaging paradigms in order to understand better the contribution of the hippocampus to each of these tasks. In the present study, we build on previous findings showing common neural activation in default network areas during episodic and spatial memory tasks based on familiar, real-world environments (Hirshhorn et al. (2012) Neuropsychologia 50:3094-3106). Following previous demonstrations of the presence of functionally connected sub-networks within the default network, we performed seed-based functional connectivity analyses to determine how, depending on the task, the hippocampus and prefrontal cortex differentially couple with one another and with distinct whole-brain networks. We found evidence for a medial prefrontal-parietal network and a medial temporal lobe network, which were functionally connected to the prefrontal and hippocampal seeds, respectively, regardless of the nature of the memory task. However, these two networks were functionally connected with one another during the episodic memory task, but not during spatial memory tasks. Replicating previous reports of fractionation of the default network into stable sub-networks, this study also shows how these sub-networks may flexibly couple and uncouple with one another based on task demands. These findings support the hypothesis that episodic memory and spatial memory share a common medial temporal lobe-based neural substrate, with episodic memory recruiting additional prefrontal sub-networks. © 2014 Wiley Periodicals, Inc.
The effects of divided attention at study and reporting procedure on regulation and monitoring for episodic recall.

PubMed

Sauer, James; Hope, Lorraine

2016-09-01

Eyewitnesses regulate the level of detail (grain size) reported to balance competing demands for informativeness and accuracy. However, research to date has predominantly examined metacognitive monitoring for semantic memory tasks, and used relatively artificial phased reporting procedures. Further, although the established role of confidence in this regulation process may affect the confidence-accuracy relation for volunteered responses in predictable ways, previous investigations of the confidence-accuracy relation for eyewitness recall have largely overlooked the regulation of response granularity. Using a non-phased paradigm, Experiment 1 compared reporting and monitoring following optimal and sub-optimal (divided attention) encoding conditions. Participants showed evidence of sacrificing accuracy for informativeness, even when memory quality was relatively weak. Participants in the divided (cf. full) attention condition showed reduced accuracy for fine- but not coarse-grained responses. However, indices of discrimination and confidence diagnosticity showed no effect of divided attention. Experiment 2 compared the effects of divided attention at encoding on reporting and monitoring using both non-phased and 2-phase procedures. Divided attention effects were consistent with Experiment 1. However, compared to those in the non-phased condition, participants in the 2-phase condition displayed a more conservative control strategy, and confidence ratings were less diagnostic of accuracy. When memory quality was reduced, although attempts to balance informativeness and accuracy increased the chance of fine-grained response errors, confidence provided an index of the likely accuracy of volunteered fine-grained responses for both condition. Copyright © 2016 Elsevier B.V. All rights reserved.
Episodic Memory: A Comparative Approach

PubMed Central

Martin-Ordas, Gema; Call, Josep

2013-01-01

Historically, episodic memory has been described as autonoetic, personally relevant, complex, context-rich, and allowing mental time travel. In contrast, semantic memory, which is theorized to be free of context and personal relevance, is noetic and consists of general knowledge of facts about the world. The field of comparative psychology has adopted this distinction in order to study episodic memory in non-human animals. Our aim in this article is not only to reflect on the concept of episodic memory and the experimental approaches used in comparative psychology to study this phenomenon, but also to provide a critical analysis of these paradigms. We conclude the article by providing new avenues for future research. PMID:23781179
Neural Correlates of Opposing Effects of Emotional Distraction on Working Memory and Episodic Memory: An Event-Related fMRI Investigation

PubMed Central

Dolcos, Florin; Iordan, Alexandru D.; Kragel, James; Stokes, Jared; Campbell, Ryan; McCarthy, Gregory; Cabeza, Roberto

2013-01-01

A fundamental question in the emotional memory literature is why emotion enhances memory in some conditions but disrupts memory in other conditions. For example, separate studies have shown that emotional stimuli tend to be better remembered in long-term episodic memory (EM), whereas emotional distracters tend to impair working memory (WM) maintenance. The first goal of this study was to directly compare the neural correlates of EM enhancement (EME) and WM impairing (WMI) effects, and the second goal was to explore individual differences in these mechanisms. During event-related functional magnetic resonance imaging (fMRI), participants maintained faces in WM while being distracted by emotional or neutral pictures presented during the delay period. EM for the distracting pictures was tested after scanning and was used to identify successful encoding activity for the picture distracters. The first goal yielded two findings: (1) emotional pictures that disrupted face WM but enhanced subsequent EM were associated with increased amygdala (AMY) and hippocampal activity (ventral system) coupled with reduced dorsolateral PFC (dlPFC) activity (dorsal system); (2) trials in which emotion enhanced EM without disrupting WM were associated with increased ventrolateral PFC activity. The ventral-dorsal switch can explain EME and WMI, while the ventrolateral PFC effect suggests a coping mechanism. The second goal yielded two additional findings: (3) participants who were more susceptible to WMI showed greater amygdala increases and PFC reductions; (4) AMY activity increased and dlPFC activity decreased with measures of attentional impulsivity. Taken together, these results clarify the mechanisms linking the enhancing and impairing effects of emotion on memory, and provide insights into the role of individual differences in the impact of emotional distraction. PMID:23761770
The Role of Episodic and Semantic Memory in Episodic Foresight

ERIC Educational Resources Information Center

Martin-Ordas, Gema; Atance, Cristina M.; Louw, Alyssa

2012-01-01

In this paper we describe a special form of future thinking, termed "episodic foresight" and its relation with episodic and semantic memory. We outline the methodologies that have largely been developed in the last five years to assess this capacity in young children and non-human animals. Drawing on Tulving's definition of episodic and semantic…
Self-appraisals and episodic memory: Different psychological factors related to patient versus informant reports of apathy in severe traumatic brain injury.

PubMed

Arnould, Annabelle; Rochat, Lucien; Azouvi, Philippe; van der Linden, Martial

2018-01-09

Apathy is a core feature in patients with traumatic brain injury (TBI). The psychological processes underlying apathy are still unclear, and the few studies conducted on this subject have essentially focused on cognitive processes and informant reports of apathetic manifestations. The aims of the present study were to examine self-reports versus informant reports of diminished initiative/interest, as well as their relationship with different cognitive factors (attention/executive mechanisms, episodic memory, and multitasking) and personal identity factors (self-esteem and self-efficacy beliefs). To this end, 74 participants (38 patients with severe TBI matched with 36 control participants) were given three questionnaires to assess self-esteem, general self-efficacy beliefs, and anxio-depressive symptoms and five tasks to assess cognitive processes, including real-life multitasking. In addition, a questionnaire that assessed self-awareness of functional competencies and a questionnaire that assessed lack of initiative/interest were administered to each participant and their relatives. The main results showed that patients demonstrated an awareness of their lack of initiative/interest and that self-reported lack of initiative/interest was best predicted by low general self-efficacy beliefs and self-esteem, whereas informant-reported lack of initiative/interest was predicted by episodic memory difficulties. These results shed new light on the psychological processes related to apathetic manifestations, as well as the differing perspectives and lived experiences of patients and external observers in the TBI population, which opens interesting prospects for psychological interventions.
Loss of attentional inhibition in older adults--Does it really exist? An experimental dissociation of inhibitory and memory retrieval processes.

PubMed

Giesen, Carina; Eberhard, Maike; Rothermund, Klaus

2015-06-01

It is commonly assumed that attentional inhibitory functioning decreases with age, even though empirical evidence is mixed. These inconsistencies possibly stem from methodological artifacts: distractor inhibition is typically assessed with the negative priming paradigm, which confounds inhibition and episodic retrieval. In the present study, we investigated age differences in a sequential distractor repetition paradigm (Giesen, Frings, & Rothermund, 2012) that provides independent estimates of distractor inhibition and episodic retrieval processes. Older (60+ yrs) and younger (below 30 years) adults identified target letters that were flanked by distractors (JKJ). Inhibitory processes were preserved in older adults, who showed reliable distractor repetition benefits resulting from persistent distractor inhibition; however, a significant loss of inhibition was apparent for the older subgroup of participants (65+ yrs) compared with a subgroup of young-old participants (60 to 64 years). No age differences were found for episodic retrieval processes of stimulus-response bindings that were indexed by an interaction of distractor repetition and response relation. Findings highlight the importance of dissociating between distractor inhibition and retrieval processes that are differently implicated in age-related cognitive change. (c) 2015 APA, all rights reserved.
The nature of the semantic/episodic memory distinction: A missing piece of the "working through" process.

PubMed

Klein, Stanley B; Markowitsch, Hans J

2015-01-01

The relations between the semantic and episodic-autobiographical memory systems are more complex than described in the target article. We argue that understanding the noetic/autonoetic distinction provides critical insights into the foundation of the delineation between the two memory systems. Clarity with respect to the criteria for classification of these two systems, and the evolving conceptualization of episodic memory, can further neuroscientifically informed therapeutic approaches.
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
Functional neuroanatomy of remote episodic, semantic and spatial memory: a unified account based on multiple trace theory

PubMed Central

Moscovitch, Morris; Rosenbaum, R Shayna; Gilboa, Asaf; Addis, Donna Rose; Westmacott, Robyn; Grady, Cheryl; McAndrews, Mary Pat; Levine, Brian; Black, Sandra; Winocur, Gordon; Nadel, Lynn

2005-01-01

We review lesion and neuroimaging evidence on the role of the hippocampus, and other structures, in retention and retrieval of recent and remote memories. We examine episodic, semantic and spatial memory, and show that important distinctions exist among different types of these memories and the structures that mediate them. We argue that retention and retrieval of detailed, vivid autobiographical memories depend on the hippocampal system no matter how long ago they were acquired. Semantic memories, on the other hand, benefit from hippocampal contribution for some time before they can be retrieved independently of the hippocampus. Even semantic memories, however, can have episodic elements associated with them that continue to depend on the hippocampus. Likewise, we distinguish between experientially detailed spatial memories (akin to episodic memory) and more schematic memories (akin to semantic memory) that are sufficient for navigation but not for re-experiencing the environment in which they were acquired. Like their episodic and semantic counterparts, the former type of spatial memory is dependent on the hippocampus no matter how long ago it was acquired, whereas the latter can survive independently of the hippocampus and is represented in extra-hippocampal structures. In short, the evidence reviewed suggests strongly that the function of the hippocampus (and possibly that of related limbic structures) is to help encode, retain, and retrieve experiences, no matter how long ago the events comprising the experience occurred, and no matter whether the memories are episodic or spatial. We conclude that the evidence favours a multiple trace theory (MTT) of memory over two other models: (1) traditional consolidation models which posit that the hippocampus is a time-limited memory structure for all forms of memory; and (2) versions of cognitive map theory which posit that the hippocampus is needed for representing all forms of allocentric space in memory. PMID:16011544

Functional neuroanatomy of remote episodic, semantic and spatial memory: a unified account based on multiple trace theory.

PubMed

Moscovitch, Morris; Rosenbaum, R Shayna; Gilboa, Asaf; Addis, Donna Rose; Westmacott, Robyn; Grady, Cheryl; McAndrews, Mary Pat; Levine, Brian; Black, Sandra; Winocur, Gordon; Nadel, Lynn

2005-07-01

We review lesion and neuroimaging evidence on the role of the hippocampus, and other structures, in retention and retrieval of recent and remote memories. We examine episodic, semantic and spatial memory, and show that important distinctions exist among different types of these memories and the structures that mediate them. We argue that retention and retrieval of detailed, vivid autobiographical memories depend on the hippocampal system no matter how long ago they were acquired. Semantic memories, on the other hand, benefit from hippocampal contribution for some time before they can be retrieved independently of the hippocampus. Even semantic memories, however, can have episodic elements associated with them that continue to depend on the hippocampus. Likewise, we distinguish between experientially detailed spatial memories (akin to episodic memory) and more schematic memories (akin to semantic memory) that are sufficient for navigation but not for re-experiencing the environment in which they were acquired. Like their episodic and semantic counterparts, the former type of spatial memory is dependent on the hippocampus no matter how long ago it was acquired, whereas the latter can survive independently of the hippocampus and is represented in extra-hippocampal structures. In short, the evidence reviewed suggests strongly that the function of the hippocampus (and possibly that of related limbic structures) is to help encode, retain, and retrieve experiences, no matter how long ago the events comprising the experience occurred, and no matter whether the memories are episodic or spatial. We conclude that the evidence favours a multiple trace theory (MTT) of memory over two other models: (1) traditional consolidation models which posit that the hippocampus is a time-limited memory structure for all forms of memory; and (2) versions of cognitive map theory which posit that the hippocampus is needed for representing all forms of allocentric space in memory.
Single-trial Phase Entrainment of Theta Oscillations in Sensory Regions Predicts Human Associative Memory Performance.

PubMed

Wang, Danying; Clouter, Andrew; Chen, Qiaoyu; Shapiro, Kimron L; Hanslmayr, Simon

2018-06-13

Episodic memories are rich in sensory information and often contain integrated information from different sensory modalities. For instance, we can store memories of a recent concert with visual and auditory impressions being integrated in one episode. Theta oscillations have recently been implicated in playing a causal role synchronizing and effectively binding the different modalities together in memory. However, an open question is whether momentary fluctuations in theta synchronization predict the likelihood of associative memory formation for multisensory events. To address this question we entrained the visual and auditory cortex at theta frequency (4 Hz) and in a synchronous or asynchronous manner by modulating the luminance and volume of movies and sounds at 4 Hz, with a phase offset at 0° or 180°. EEG activity from human subjects (both sexes) was recorded while they memorized the association between a movie and a sound. Associative memory performance was significantly enhanced in the 0° compared to the 180° condition. Source-level analysis demonstrated that the physical stimuli effectively entrained their respective cortical areas with a corresponding phase offset. The findings suggested a successful replication of a previous study (Clouter et al., 2017). Importantly, the strength of entrainment during encoding correlated with the efficacy of associative memory such that small phase differences between visual and auditory cortex predicted a high likelihood of correct retrieval in a later recall test. These findings suggest that theta oscillations serve a specific function in the episodic memory system: Binding the contents of different modalities into coherent memory episodes. SIGNIFICANCE STATEMENT How multi-sensory experiences are bound to form a coherent episodic memory representation is one of the fundamental questions in human episodic memory research. Evidence from animal literature suggests that the relative timing between an input and theta oscillations in the hippocampus is crucial for memory formation. We precisely controlled the timing between visual and auditory stimuli and the neural oscillations at 4 Hz using a multisensory entrainment paradigm. Human associative memory formation depends on coincident timing between sensory streams processed by the corresponding brain regions. We provide evidence for a significant role of relative timing of neural theta activity in human episodic memory on a single trial level, which reveals a crucial mechanism underlying human episodic memory. Copyright © 2018 the authors.
Spatial and Temporal Episodic Memory Retrieval Recruit Dissociable Functional Networks in the Human Brain

ERIC Educational Resources Information Center

Ekstrom, Arne D.; Bookheimer, Susan Y.

2007-01-01

Imaging, electrophysiological studies, and lesion work have shown that the medial temporal lobe (MTL) is important for episodic memory; however, it is unclear whether different MTL regions support the spatial, temporal, and item elements of episodic memory. In this study we used fMRI to examine retrieval performance emphasizing different aspects…
Bridging the Gap between Brain and Behavior: Cognitive and Neural Mechanisms of Episodic Memory

ERIC Educational Resources Information Center

Eichenbaum, Howard; Fortin, Norbert J.

2005-01-01

The notion that non-human animals are capable of episodic memory is highly controversial. Here, we review recent behavioral work from our laboratory showing that the fundamental features of episodic memory can be observed in rats and that, as in humans, this capacity relies on the hippocampus. We also discuss electrophysiological evidence, from…
Memory Dysfunction

PubMed Central

Matthews, Brandy R.

2015-01-01

Purpose of Review: This article highlights the dissociable human memory systems of episodic, semantic, and procedural memory in the context of neurologic illnesses known to adversely affect specific neuroanatomic structures relevant to each memory system. Recent Findings: Advances in functional neuroimaging and refinement of neuropsychological and bedside assessment tools continue to support a model of multiple memory systems that are distinct yet complementary and to support the potential for one system to be engaged as a compensatory strategy when a counterpart system fails. Summary: Episodic memory, the ability to recall personal episodes, is the subtype of memory most often perceived as dysfunctional by patients and informants. Medial temporal lobe structures, especially the hippocampal formation and associated cortical and subcortical structures, are most often associated with episodic memory loss. Episodic memory dysfunction may present acutely, as in concussion; transiently, as in transient global amnesia (TGA); subacutely, as in thiamine deficiency; or chronically, as in Alzheimer disease. Semantic memory refers to acquired knowledge about the world. Anterior and inferior temporal lobe structures are most often associated with semantic memory loss. The semantic variant of primary progressive aphasia (svPPA) is the paradigmatic disorder resulting in predominant semantic memory dysfunction. Working memory, associated with frontal lobe function, is the active maintenance of information in the mind that can be potentially manipulated to complete goal-directed tasks. Procedural memory, the ability to learn skills that become automatic, involves the basal ganglia, cerebellum, and supplementary motor cortex. Parkinson disease and related disorders result in procedural memory deficits. Most memory concerns warrant bedside cognitive or neuropsychological evaluation and neuroimaging to assess for specific neuropathologies and guide treatment. PMID:26039844
The effects of sleep on episodic memory in older and younger adults.

PubMed

Aly, Mariam; Moscovitch, Morris

2010-04-01

Evidence on sleep-dependent benefits for episodic memory remains elusive. Furthermore we know little about age-related changes on the effects of sleep on episodic memory. The study we report is the first to compare the effects of sleep on episodic memories in younger and older adults. Memories of stories and personal events were assessed following a retention interval that included sleep and following an equal duration of wakefulness. Both older and younger adults have superior memory following sleep compared to following wakefulness for both types of material. Amount of forgetting of personal events was less during wakefulness in older adults than in younger adults, possibly due to spontaneous rehearsal. Amount of time spent sleeping correlated highly with sleep benefit in older adults, suggesting that quantity of total sleep, and/or time spent in some stages of sleep, are important contributors to age-related differences in memory consolidation or protection from interference during sleep.
Further evidence that similar principles govern recall from episodic and semantic memory: the Canadian prime ministerial serial position function.

PubMed

Neath, Ian; Saint-Aubin, Jean

2011-06-01

The serial position function, with its characteristic primacy and recency effects, is one of the most ubiquitous findings in episodic memory tasks. In contrast, there are only two demonstrations of such functions in tasks thought to tap semantic memory. Here, we provide a third demonstration, showing that free recall of the prime ministers of Canada also results in a serial position function. Scale Independent Memory, Perception, and Learning (SIMPLE), a local distinctiveness model of memory that was designed to account for serial position effects in episodic memory, fit the data. According to SIMPLE, serial position functions observed in episodic and semantic memory all reflect the relative distinctiveness principle: items will be well remembered to the extent that they are more distinct than competing items at the time of retrieval. (PsycINFO Database Record (c) 2011 APA, all rights reserved).
Decomposing the relationship between cognitive functioning and self-referent memory beliefs in older adulthood: What’s memory got to do with it?

PubMed Central

Payne, Brennan R.; Gross, Alden L.; Hill, Patrick L.; Parisi, Jeanine M.; Rebok, George W.; Stine-Morrow, Elizabeth A. L.

2018-01-01

With advancing age, episodic memory performance shows marked declines along with concurrent reports of lower subjective memory beliefs. Given that normative age-related declines in episodic memory co-occur with declines in other cognitive domains, we examined the relationship between memory beliefs and multiple domains of cognitive functioning. Confirmatory bi-factor structural equation models were used to parse the shared and independent variance among factors representing episodic memory, psychomotor speed, and executive reasoning in one large cohort study (Senior Odyssey, N = 462), and replicated using another large cohort of healthy older adults (ACTIVE, N = 2,802). Accounting for a general fluid cognitive functioning factor (comprised of the shared variance among measures of episodic memory, speed, and reasoning) attenuated the relationship between objective memory performance and subjective memory beliefs in both samples. Moreover, the general cognitive functioning factor was the strongest predictor of memory beliefs in both samples. These findings are consistent with the notion that dispositional memory beliefs may reflect perceptions of cognition more broadly. This may be one reason why memory beliefs have broad predictive validity for interventions that target fluid cognitive ability. PMID:27685541
Decomposing the relationship between cognitive functioning and self-referent memory beliefs in older adulthood: what's memory got to do with it?

PubMed

Payne, Brennan R; Gross, Alden L; Hill, Patrick L; Parisi, Jeanine M; Rebok, George W; Stine-Morrow, Elizabeth A L

2017-07-01

With advancing age, episodic memory performance shows marked declines along with concurrent reports of lower subjective memory beliefs. Given that normative age-related declines in episodic memory co-occur with declines in other cognitive domains, we examined the relationship between memory beliefs and multiple domains of cognitive functioning. Confirmatory bi-factor structural equation models were used to parse the shared and independent variance among factors representing episodic memory, psychomotor speed, and executive reasoning in one large cohort study (Senior Odyssey, N = 462), and replicated using another large cohort of healthy older adults (ACTIVE, N = 2802). Accounting for a general fluid cognitive functioning factor (comprised of the shared variance among measures of episodic memory, speed, and reasoning) attenuated the relationship between objective memory performance and subjective memory beliefs in both samples. Moreover, the general cognitive functioning factor was the strongest predictor of memory beliefs in both samples. These findings are consistent with the notion that dispositional memory beliefs may reflect perceptions of cognition more broadly. This may be one reason why memory beliefs have broad predictive validity for interventions that target fluid cognitive ability.
The Episodic Memory System: Neurocircuitry and Disorders

PubMed Central

Dickerson, Bradford C; Eichenbaum, Howard

2010-01-01

The ability to encode and retrieve our daily personal experiences, called episodic memory, is supported by the circuitry of the medial temporal lobe (MTL), including the hippocampus, which interacts extensively with a number of specific distributed cortical and subcortical structures. In both animals and humans, evidence from anatomical, neuropsychological, and physiological studies indicates that cortical components of this system have key functions in several aspects of perception and cognition, whereas the MTL structures mediate the organization and persistence of the network of memories whose details are stored in those cortical areas. Structures within the MTL, and particularly the hippocampus, have distinct functions in combining information from multiple cortical streams, supporting our ability to encode and retrieve details of events that compose episodic memories. Conversely, selective damage in the hippocampus, MTL, and other structures of the large-scale memory system, or deterioration of these areas in several diseases and disorders, compromises episodic memory. A growing body of evidence is converging on a functional organization of the cortical, subcortical, and MTL structures that support the fundamental features of episodic memory in humans and animals. PMID:19776728
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.
Behavioral and functional neuroanatomical correlates of anterograde autobiographical memory in isolated retrograde amnesic patient M.L.

PubMed

Levine, Brian; Svoboda, Eva; Turner, Gary R; Mandic, Marina; Mackey, Allison

2009-09-01

Patient M.L. [Levine, B., Black, S. E., Cabeza, R., Sinden, M., Mcintosh, A. R., Toth, J. P., et al. (1998). Episodic memory and the self in a case of isolated retrograde amnesia. Brain, 121, 1951-1973], lost memory for events occurring before his severe traumatic brain injury, yet his anterograde (post-injury) learning and memory appeared intact, a syndrome known as isolated or focal retrograde amnesia. Studies with M.L. demonstrated a dissociation between episodic and semantic memory. His retrograde amnesia was specific to episodic autobiographical memory. Convergent behavioral and functional imaging data suggested that his anterograde memory, while appearing normal, was accomplished with reduced autonoetic awareness (awareness of the self as a continuous entity across time that is a crucial element of episodic memory). While previous research on M.L. focused on anterograde memory of laboratory stimuli, in this study, M.L.'s autobiographical memory for post-injury events or anterograde autobiographical memory was examined using prospective collection of autobiographical events via audio diary with detailed behavioral and functional neuroanatomical analysis. Consistent with his reports of subjective disconnection from post-injury autobiographical events, M.L. assigned fewer "remember" ratings to his autobiographical events than comparison subjects. His generation of event-specific details using the Autobiographical Interview [Levine, B., Svoboda, E., Hay, J., Winocur, G., & Moscovitch, M. (2002). Aging and autobiographical memory: dissociating episodic from semantic retrieval. Psychology and Aging, 17, 677-689] was low, but not significantly so, suggesting that it is possible to generate episodic-like details even when re-experiencing of those details is compromised. While listening to the autobiographical audio diary segments, M.L. showed reduced activation relative to comparison subjects in midline frontal and posterior nodes previously identified as part of the autobiographical memory network. Reductions were also evident in M.L. in association with personal semantic stimuli (e.g., recordings describing personal habits and routines). These data suggest an association between M.L.'s impoverished recollection of autobiographical material and reduced activation in midline sectors of the autobiographical memory network that support the autonoetic, first-person element of episodic memory.
Neural Systems Involved When Attending to a Speaker

PubMed Central

Kamourieh, Salwa; Braga, Rodrigo M.; Leech, Robert; Newbould, Rexford D.; Malhotra, Paresh; Wise, Richard J. S.

2015-01-01

Remembering what a speaker said depends on attention. During conversational speech, the emphasis is on working memory, but listening to a lecture encourages episodic memory encoding. With simultaneous interference from background speech, the need for auditory vigilance increases. We recreated these context-dependent demands on auditory attention in 2 ways. The first was to require participants to attend to one speaker in either the absence or presence of a distracting background speaker. The second was to alter the task demand, requiring either an immediate or delayed recall of the content of the attended speech. Across 2 fMRI studies, common activated regions associated with segregating attended from unattended speech were the right anterior insula and adjacent frontal operculum (aI/FOp), the left planum temporale, and the precuneus. In contrast, activity in a ventral right frontoparietal system was dependent on both the task demand and the presence of a competing speaker. Additional multivariate analyses identified other domain-general frontoparietal systems, where activity increased during attentive listening but was modulated little by the need for speech stream segregation in the presence of 2 speakers. These results make predictions about impairments in attentive listening in different communicative contexts following focal or diffuse brain pathology. PMID:25596592
Episodic Memory Retrieval Functionally Relies on Very Rapid Reactivation of Sensory Information.

PubMed

Waldhauser, Gerd T; Braun, Verena; Hanslmayr, Simon

2016-01-06

Episodic memory retrieval is assumed to rely on the rapid reactivation of sensory information that was present during encoding, a process termed "ecphory." We investigated the functional relevance of this scarcely understood process in two experiments in human participants. We presented stimuli to the left or right of fixation at encoding, followed by an episodic memory test with centrally presented retrieval cues. This allowed us to track the reactivation of lateralized sensory memory traces during retrieval. Successful episodic retrieval led to a very early (∼100-200 ms) reactivation of lateralized alpha/beta (10-25 Hz) electroencephalographic (EEG) power decreases in the visual cortex contralateral to the visual field at encoding. Applying rhythmic transcranial magnetic stimulation to interfere with early retrieval processing in the visual cortex led to decreased episodic memory performance specifically for items encoded in the visual field contralateral to the site of stimulation. These results demonstrate, for the first time, that episodic memory functionally relies on very rapid reactivation of sensory information. Remembering personal experiences requires a "mental time travel" to revisit sensory information perceived in the past. This process is typically described as a controlled, relatively slow process. However, by using electroencephalography to measure neural activity with a high time resolution, we show that such episodic retrieval entails a very rapid reactivation of sensory brain areas. Using transcranial magnetic stimulation to alter brain function during retrieval revealed that this early sensory reactivation is causally relevant for conscious remembering. These results give first neural evidence for a functional, preconscious component of episodic remembering. This provides new insight into the nature of human memory and may help in the understanding of psychiatric conditions that involve the automatic intrusion of unwanted memories. Copyright © 2016 the authors 0270-6474/16/360251-10$15.00/0.
Neural Activations of Guided Imagery and Music in Negative Emotional Processing: A Functional MRI Study.

PubMed

Lee, Sang Eun; Han, Yeji; Park, HyunWook

2016-01-01

The Bonny Method of Guided Imagery and Music uses music and imagery to access and explore personal emotions associated with episodic memories. Understanding the neural mechanism of guided imagery and music (GIM) as combined stimuli for emotional processing informs clinical application. We performed functional magnetic resonance imaging (fMRI) to demonstrate neural mechanisms of GIM for negative emotional processing when personal episodic memory is recalled and re-experienced through GIM processes. Twenty-four healthy volunteers participated in the study, which used classical music and verbal instruction stimuli to evoke negative emotions. To analyze the neural mechanism, activated regions associated with negative emotional and episodic memory processing were extracted by conducting volume analyses for the contrast between GIM and guided imagery (GI) or music (M). The GIM stimuli showed increased activation over the M-only stimuli in five neural regions associated with negative emotional and episodic memory processing, including the left amygdala, left anterior cingulate gyrus, left insula, bilateral culmen, and left angular gyrus (AG). Compared with GI alone, GIM showed increased activation in three regions associated with episodic memory processing in the emotional context, including the right posterior cingulate gyrus, bilateral parahippocampal gyrus, and AG. No neural regions related to negative emotional and episodic memory processing showed more activation for M and GI than for GIM. As a combined multimodal stimulus, GIM may increase neural activations related to negative emotions and episodic memory processing. Findings suggest a neural basis for GIM with personal episodic memories affecting cortical and subcortical structures and functions. © the American Music Therapy Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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.
More Effective Consolidation of Episodic Long-Term Memory in Children Than Adults-Unrelated to Sleep.

PubMed

Wang, Jing-Yi; Weber, Frederik D; Zinke, Katharina; Inostroza, Marion; Born, Jan

2017-06-08

Abilities to encode and remember events in their spatiotemporal context (episodic memory) rely on brain regions that mature late during childhood and are supported by sleep. We compared the temporal dynamics of episodic memory formation and the role of sleep in this process between 62 children (8-12 years) and 57 adults (18-37 years). Subjects recalled "what-where-when" memories after a short 1-hr retention interval or after a long 10.5-hr interval containing either nocturnal sleep or daytime wakefulness. Although children showed diminished recall of episodes after 1 hr, possibly resulting from inferior encoding, unlike adults, they showed no further decrease in recall after 10.5 hr. In both age groups, episodic memory benefitted from sleep. However, children's more effective offline retention was unrelated to sleep. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.
Obesity and insulin resistance are associated with reduced activity in core memory regions of the brain.

PubMed

Cheke, Lucy G; Bonnici, Heidi M; Clayton, Nicola S; Simons, Jon S

2017-02-01

Increasing research in animals and humans suggests that obesity may be associated with learning and memory deficits, and in particular with reductions in episodic memory. Rodent models have implicated the hippocampus in obesity-related memory impairments, but the neural mechanisms underlying episodic memory deficits in obese humans remain undetermined. In the present study, lean and obese human participants were scanned using fMRI while completing a What-Where-When episodic memory test (the "Treasure-Hunt Task") that assessed the ability to remember integrated item, spatial, and temporal details of previously encoded complex events. In lean participants, the Treasure-Hunt task elicited significant activity in regions of the brain known to be important for recollecting episodic memories, such as the hippocampus, angular gyrus, and dorsolateral prefrontal cortex. Both obesity and insulin resistance were associated with significantly reduced functional activity throughout the core recollection network. These findings indicate that obesity is associated with reduced functional activity in core brain areas supporting episodic memory and that insulin resistance may be a key player in this association. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Some Surprising Findings on the Involvement of the Parietal Lobe in Human Memory

PubMed Central

Olson, Ingrid R.; Berryhill, Marian

2009-01-01

The posterior parietal lobe is known to play some role in a far-flung list of mental processes: linking vision to action (saccadic eye movements, reaching, grasping), attending to visual space, numerical calculation, and mental rotation. Here we review findings from humans and monkeys that illuminate an untraditional function of this region: memory. Our review draws on neuroimaging findings that have repeatedly identified parietal lobe activations associated with short-term or working memory and episodic memory. We also discuss recent neuropsychological findings showing that individuals with parietal lobe damage exhibit both working memory and long-term memory deficits. These deficits are not ubiquitous; they are only evident under certain retrieval demands. Our review elaborates on these findings and evaluates various theories about the mechanistic role of the posterior parietal lobe in memory. The available data point towards the conclusion that the posterior parietal lobe plays an important role in memory retrieval irrespective of elapsed time. The two models that are best supported by existing data are the Attention to Memory Model and the Subjective Memory Model. We conclude by formalizing several open questions that are intended to encourage future research. PMID:18848635
Neurocognitive deficits or stress overload: Why do individuals with schizophrenia show poor performance in neurocognitive tests?

PubMed

Krkovic, Katarina; Moritz, Steffen; Lincoln, Tania M

2017-05-01

Poor performance in neurocognitive tasks is consistently found across studies in all stages of schizophrenia spectrum disorders and is interpreted as an underlying, brain function-related, neurocognitive deficit. However, neurocognitive test performance in schizophrenia might be compromised by patients' increased stress level. We investigated group-differences in neurocognitive performance while accounting for psychophysiological (salivary cortisol, heart rate, skin conductance level) and self-reported stress. We included 35 patients with schizophrenia, 29 participants with attenuated psychotic symptoms, 26 first-degree relatives of individuals with schizophrenia and 28 healthy controls. Participants completed a neurocognitive test battery that assessed processing speed, task switching, attention, working memory, verbal episodic memory, and verbal comprehension. Multivariate analyses of covariance (MANCOVA) were calculated to test for main effects of group on neurocognitive performance thereby not accounting versus accounting for confounding effects of stress. As expected, patients with schizophrenia scored lower than the other groups in all neurocognitive domains. Participants with attenuated psychotic symptoms, first-degree relatives and healthy individuals did not differ from each other in their performance. After accounting for heart rate and self-reported stress, the multivariate effect of group on neurocognition remained significant, but was rendered non-significant for specific domains - working memory capacity, episodic memory, and long-term memory. The findings imply that stress is relevant to neurocognitive performance and this should be taken into account when interpreting the origin of performance deficits in schizophrenia patients. Copyright © 2016 Elsevier B.V. All rights reserved.

The Effects of Emotion on Episodic Memory for TV Commercials.

ERIC Educational Resources Information Center

Thorson, Esther; Friestad, Marian

Based on the associational nature of memory, the distinction between episodic and semantic memory, and the notion of memory strength, a model was developed of the role of emotion in the memory of television commercials. The model generated the following hypotheses: (1) emotional commercials will more likely be recalled than nonemotional…
Unilateral prefrontal direct current stimulation effects are modulated by working memory load and gender.

PubMed

Meiron, Oded; Lavidor, Michal

2013-05-01

Recent studies revealed that anodal transcranial direct current stimulation (tDCS) to the left dorsolateral prefrontal cortex (DLPFC) may improve verbal working memory (WM) performance in humans. In the present study, we evaluated executive attention, which is the core of WM capacity, considered to be significantly involved in tasks that require active maintenance of memory representations in interference-rich conditions, and is highly dependent on DLPFC function. We investigated verbal WM accuracy using a WM task that is highly sensitive to executive attention function. We were interested in how verbal WM accuracy may be affected by WM load, unilateral DLPFC stimulation, and gender, as previous studies showed gender-dependent brain activation during verbal WM tasks. We utilized a modified verbal n-Back task hypothesized to increase demands on executive attention. We examined "online" WM performance while participants received transcranial direct current stimulation (tDCS), and implicit learning performance in a post-stimulation WM task. Significant lateralized "online" stimulation effects were found only in the highest WM load condition revealing that males benefit from left DLPFC stimulation, while females benefit from right DLPFC stimulation. High WM load performance in the left DLPFC stimulation was significantly related to post-stimulation recall performance. Our findings support the idea that lateralized stimulation effects in high verbal WM load may be gender-dependent. Further, our post-stimulation results support the idea that increased left hemisphere activity may be important for encoding verbal information into episodic memory as well as for facilitating retrieval of context-specific targets from semantic memory. Copyright © 2013 Elsevier Inc. All rights reserved.
A face to remember: emotional expression modulates prefrontal activity during memory formation.

PubMed

Sergerie, Karine; Lepage, Martin; Armony, Jorge L

2005-01-15

Emotion can exert a modulatory role on episodic memory. Several studies have shown that negative stimuli (e.g., words, pictures) are better remembered than neutral ones. Although facial expressions are powerful emotional stimuli and have been shown to influence perception and attention processes, little is known about their effect on memory. We used functional magnetic resonance imaging (fMRI) in humans to investigate the effects of expression (happy, neutral, and fearful) on prefrontal cortex (PFC) activity during the encoding of faces, using a subsequent memory effect paradigm. Our results show that activity in right PFC predicted memory for faces, regardless of expression, while a homotopic region in the left hemisphere was associated with successful encoding only for faces with an emotional expression. These findings are consistent with the proposed role of right dorsolateral PFC in successful encoding of nonverbal material, but also suggest that left DLPFC may be a site where integration of memory and emotional processes occurs. This study sheds new light on the current controversy regarding the hemispheric lateralization of PFC in memory encoding.
Memory Functioning in Children and Adolescents With Autism

PubMed Central

Southwick, Jason S.; Bigler, Erin D.; Froehlich, Alyson; DuBray, Molly B.; Alexander, Andrew L.; Lange, Nicholas; Lainhart, Janet E.

2012-01-01

Objective Memory functioning in children and adolescents ages 5–19 with autism (n = 50) and typically developing controls (n = 36) was assessed using a clinical assessment battery, the Test of Memory and Learning (TOMAL). Method Participant groups were statistically comparable in age, nonverbal IQ, handedness, and head circumference, and were administered the TOMAL. Results Test performance on the TOMAL demonstrated broad differences in memory functioning in the autism group, across multiple task formats, including verbal and nonverbal, immediate and delayed, attention and concentration, sequential recall, free recall, associative recall, and multiple-trial learning memory. All index and nearly all subtest differences remained significant even after comparing a subset of the autism group (n = 36) and controls that were matched for verbal IQ ( p >.05). However, retention of previously remembered information after a delay was similar in autism and controls. Conclusions These findings indicate that performance on measures of episodic memory is broadly reduced in autism, and support the conclusion that information encoding and organization, possibly due to inefficient cognitive processing strategies, rather than storage and retrieval, are the primary factors that limit memory performance in autism. PMID:21843004
Cognitive processing of food rewards.

PubMed

Higgs, Suzanne

2016-09-01

Cues associated with tasty foods, such as their smell or taste, are strong motivators of eating, but the power of food cues on behaviour varies from moment to moment and from person to person. Variation in the rewarding value of a food with metabolic state explains why food cues are more attractive when hungry. However, cognitive processes are also important determinants of our responses to food cues. An urge to consume a tempting food may be resisted if, for example, a person has a longer term goal of weight loss. There is also evidence that responses to food cues can be facilitated or inhibited by memory processes. The aim of this review is to add to the literature on cognitive control of eating by reviewing recent evidence on the influence of working memory and episodic memory processes on responses to food cues. It is argued that processing of food information in working memory affects how much attention is paid to food cues in the environment and promotes the motivation to seek out food in the absence of direct contact with food cues. It is further argued that memories of specific recent eating episodes play an important role in directing food choices and influencing when and how much we eat. However, these memory processes are prone to disruption. When this happens, eating behaviour may become more cue-driven and less flexible. In the modern food environment, disruption of cognitive processing of food reward cues may lead to overconsumption and obesity. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.
The relative contribution of neurocognition and social cognition to 6-month vocational outcomes following Individual Placement and Support in first-episode psychosis.

PubMed

Allott, Kelly A; Cotton, Susan M; Chinnery, Gina L; Baksheev, Gennady N; Massey, Jessica; Sun, Pamela; Collins, Zoe; Barlow, Emma; Broussard, Christina; Wahid, Tasha; Proffitt, Tina-Marie; Jackson, Henry J; Killackey, Eoin

2013-10-01

To examine whether baseline neurocognition and social cognition predict vocational outcomes over 6 months in patients with first-episode psychosis (FEP) enrolled in a randomised controlled trial of Individual Placement and Support (IPS) versus treatment as usual (TAU). 135 FEP participants (IPS n=69; TAU n=66) completed a comprehensive neurocognitive and social cognitive battery. Principal axis factor analysis using PROMAX rotation was used to determine the underlying cognitive structure of the battery. Setwise (hierarchical) logistic and multivariate linear regressions were used to examine predictors of: (a) enrolment in education and employment; and (b) hours of employment over 6 months. Neurocognition and social cognition factors were entered into the models after accounting for premorbid IQ, baseline functioning and treatment group. Six cognitive factors were extracted: (i) social cognition; (ii) information processing speed; (iii) verbal learning and memory; (iv) attention and working memory; (v) visual organisation and memory; and (vi) verbal comprehension. Enrolment in education over 6 months was predicted by enrolment in education at baseline (p=.002) and poorer visual organisation and memory (p=.024). Employment over 6 months was predicted by employment at baseline (p=.041) and receiving IPS (p=.020). Better visual organisation and memory predicted total hours of paid work over 6 months (p<.001). Visual organisation and memory predicted the enrolment in education and duration of employment, after accounting for premorbid IQ, baseline functioning and treatment. Social cognition did not contribute to the prediction of vocational outcomes. Neurocognitive interventions may enhance employment duration in FEP. © 2013 Elsevier B.V. All rights reserved.
Recovering and Preventing Loss of Detailed Memory: Differential Rates of Forgetting for Detail Types in Episodic Memory

ERIC Educational Resources Information Center

Sekeres, Melanie J.; Bonasia, Kyra; St-Laurent, Marie; Pishdadian, Sara; Winocur, Gordon; Grady, Cheryl; Moscovitch, Morris

2016-01-01

Episodic memories undergo qualitative changes with time, but little is known about how different aspects of memory are affected. Different types of information in a memory, such as perceptual detail, and central themes, may be lost at different rates. In patients with medial temporal lobe damage, memory for perceptual details is severely impaired,…
Emotional Memory Persists Longer than Event Memory

ERIC Educational Resources Information Center

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

2010-01-01

The interaction between amygdala-driven and hippocampus-driven activities is expected to explain why emotion enhances episodic memory recognition. However, overwhelming behavioral evidence regarding the emotion-induced enhancement of immediate and delayed episodic memory recognition has not been obtained in humans. We found that the recognition…
Remembering episodic memories is not necessary for forgetting of negative words: Semantic retrieval can cause forgetting of negative words.

PubMed

Kobayashi, Masanori; Tanno, Yoshihiko

2015-06-01

Retrieval of a memory can induce forgetting of other related memories, which is known as retrieval-induced forgetting. Although most studies have investigated retrieval-induced forgetting by remembering episodic memories, this also can occur by remembering semantic memories. The present study shows that retrieval of semantic memories can lead to forgetting of negative words. In two experiments, participants learned words and then engaged in retrieval practice where they were asked to recall words related to the learned words from semantic memory. Finally, participants completed a stem-cued recall test for the learned words. The results showed forgetting of neutral and negative words, which was characteristic of semantic retrieval-induced forgetting. A certain degree of overlapping features, except same learning episode, is sufficient to cause retrieval-induced forgetting of negative words. Given the present results, we conclude that retrieval-induced forgetting of negative words does not require recollection of episodic memories.
Sexual Activity and Cognitive Decline in Older Adults.

PubMed

Allen, Mark S

2018-05-16

This prospective study tested whether sexual activity and emotional closeness during partnered sexual activity relate to cognitive decline (episodic memory performance) in older adulthood. In total, 6016 adults aged 50 and over (2672 men, 3344 women; M age = 66.0 ± 8.8 years) completed an episodic memory task and self-report questions related to health, sexual activity, and emotional closeness. Two years later, participants again completed the episodic memory task. After controlling for demographic and health-related lifestyle factors, more frequent sexual activity and greater emotional closeness during partnered sexual activity were associated with better memory performance. The association between sexual activity and memory performance was stronger among older participants in the sample. Memory performance worsened over 2 years, but change in memory performance was unrelated to sexual activity or emotional closeness during partnered sexual activity. These findings build on experimental research that has found sexual activity enhances episodic memory in non-human animals. Further research using longer timeframes and alternative measures of cognitive decline is recommended.
Adaptive scaling of reward in episodic memory: a replication study.

PubMed

Mason, Alice; Ludwig, Casimir; Farrell, Simon

2017-11-01

Reward is thought to enhance episodic memory formation via dopaminergic consolidation. Bunzeck, Dayan, Dolan, and Duzel [(2010). A common mechanism for adaptive scaling of reward and novelty. Human Brain Mapping, 31, 1380-1394] provided functional magnetic resonance imaging (fMRI) and behavioural evidence that reward and episodic memory systems are sensitive to the contextual value of a reward-whether it is relatively higher or lower-as opposed to absolute value or prediction error. We carried out a direct replication of their behavioural study and did not replicate their finding that memory performance associated with reward follows this pattern of adaptive scaling. An effect of reward outcome was in the opposite direction to that in the original study, with lower reward outcomes leading to better memory than higher outcomes. There was a marginal effect of reward context, suggesting that expected value affected memory performance. We discuss the robustness of the reward memory relationship to variations in reward context, and whether other reward-related factors have a more reliable influence on episodic memory.
A Cognitive Assessment of Highly Superior Autobiographical Memory

PubMed Central

LePort, Aurora K.R.; Stark, Shauna M.; McGaugh, James L.; Stark, Craig E.L.

2017-01-01

Highly Superior Autobiographical Memory (HSAM) is characterized as the ability to accurately recall an exceptional number of experiences and their associated dates from events occurring throughout much of one’s lifetime. The source of this ability has only begun to be explored. The present study explores whether other enhanced cognitive processes may be critical influences underlying HSAM abilities. We investigated whether enhanced abilities in the domains of verbal fluency, attention/inhibition, executive functioning, mnemonic discrimination, perception, visual working memory, or the processing of and memory for emotional details might contribute critically to HSAM. The results suggest that superior cognitive functioning is an unlikely basis of HSAM, as only modest advantages were found in only a few tests. In addition, we examined HSAM subjects’ memory of the testing episodes. Interestingly, HSAM participants recalled details of their own experiences far better than those experiences that the experimenter shared with them. These findings provide additional evidence that HSAM involves, relatively selectively, recollection of personal, autobiographical material. PMID:26982996
A cognitive assessment of highly superior autobiographical memory.

PubMed

LePort, Aurora K R; Stark, Shauna M; McGaugh, James L; Stark, Craig E L

2017-02-01

Highly Superior Autobiographical Memory (HSAM) is characterised as the ability to accurately recall an exceptional number of experiences and their associated dates from events occurring throughout much of one's lifetime. The source of this ability has only begun to be explored. The present study explores whether other enhanced cognitive processes may be critical influences underlying HSAM abilities. We investigated whether enhanced abilities in the domains of verbal fluency, attention/inhibition, executive functioning, mnemonic discrimination, perception, visual working memory, or the processing of and memory for emotional details might contribute critically to HSAM. The results suggest that superior cognitive functioning is an unlikely basis of HSAM, as only modest advantages were found in only a few tests. In addition, we examined HSAM subjects' memory of the testing episodes. Interestingly, HSAM participants recalled details of their own experiences far better than those experiences that the experimenter shared with them. These findings provide additional evidence that HSAM involves, relatively selectively, recollection of personal, autobiographical material.
Cognitive and contextual correlates of spontaneous and deliberate mind-wandering.

PubMed

Robison, Matthew K; Unsworth, Nash

2018-01-01

Individuals with greater cognitive abilities generally show reduced rates of mind-wandering when completing relatively demanding tasks (Randall, Oswald, & Beier, 2014). However, it is yet unclear whether elevated rates of mind-wandering among low-ability individuals are manifestations of deliberate, intentional episodes of mind-wandering because of task disengagement or lack of motivation, or to spontaneous, unintentional failures to maintain task-oriented attention. The present study examined this issue by measuring working memory capacity (WMC), mind-wandering during 3 relatively demanding attention control tasks, and contextual variables (e.g., motivation, alertness, perceptions of task unpleasantness). Results indicated that the relationship between WMC and mind-wandering was primarily driven by spontaneous episodes. Lack of alertness also uniquely predicted more frequent spontaneous mind-wandering independently of WMC. Deliberate mind-wandering was primarily driven by a lack of motivation. Thus, cognitive and contextual factors can have distinct relationships with spontaneous and deliberate mind-wandering. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Supporting the self-concept with memory: insight from amnesia.

PubMed

Grilli, Matthew D; Verfaellie, Mieke

2015-12-01

We investigated the extent to which personal semantic memory supports the self-concept in individuals with medial temporal lobe amnesia and healthy adults. Participants completed eight 'I Am' self-statements. For each of the four highest ranked self-statements, participants completed an open-ended narrative task, during which they provided supporting information indicating why the I Am statement was considered self-descriptive. Participants then completed an episodic probe task, during which they attempted to retrieve six episodic memories for each of these self-statements. Supporting information was scored as episodic, personal semantic or general semantic. In the narrative task, personal semantic memory predominated as self-supporting information in both groups. The amnesic participants generated fewer personal semantic memories than controls to support their self-statements, a deficit that was more pronounced for trait relative to role self-statements. In the episodic probe task, the controls primarily generated unique event memories, but the amnesic participants did not. These findings demonstrate that personal semantic memory, in particular autobiographical fact knowledge, plays a critical role in supporting the self-concept, regardless of the accessibility of episodic memories, and they highlight potential differences in the way traits and roles are supported by personal memory. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
A Diffusion Model Analysis of Adult Age Differences in Episodic and Semantic Long-Term Memory Retrieval

ERIC Educational Resources Information Center

Spaniol, Julia; Madden, David J.; Voss, Andreas

2006-01-01

Two experiments investigated adult age differences in episodic and semantic long-term memory tasks, as a test of the hypothesis of specific age-related decline in context memory. Older adults were slower and exhibited lower episodic accuracy than younger adults. Fits of the diffusion model (R. Ratcliff, 1978) revealed age-related increases in…
A Comparison of Preschoolers' Memory, Knowledge, and Anticipation of Events

ERIC Educational Resources Information Center

Quon, Elizabeth; Atance, Cristina M.

2010-01-01

This study examined the development of the episodic and semantic memory systems, with an emphasis on the emergence of the two aspects of the former: episodic memory (the ability to re-experience a past event) and episodic future thinking (the ability to pre-experience a future event). Three-, 4-, and 5-year olds were randomly assigned to one of…
Metamemory in children with autism: exploring "feeling-of-knowing" in episodic and semantic memory.

PubMed

Wojcik, Dominika Z; Moulin, Chris J A; Souchay, Celine

2013-01-01

Autism spectrum disorder (ASD) is a neurodevelopmental disorder primarily affecting social function and communication. Recently, there has been an interest in whether people with ASD also show memory deficits. Studies in ASD have revealed subtle impairments on tasks requiring participants to learn new information (episodic memory), but intact performance on general knowledge tasks (semantic memory). The novelty of this study was to explore metamemory (i.e., awareness of memory performance) and to examine whether children with ASD suffer from a generalized metamemory deficit common to all forms of memory, or would only present deficits on episodic metamemory tasks. To assess metamemory functioning we administered 2 feeling-of-knowing (FOK) tasks, 1 for episodic and 1 for semantic materials. In these tasks, participants are asked to predict the likelihood of subsequently recognizing currently unrecalled information. It was found that children with autism made inaccurate FOK predictions, but only for episodic materials. A specific deficit in meta-cognition emerges for only one set of materials. We argue that this deficit can be conceived of as reflecting a deficit in recollection, stemming from an inability to cast the self in the past and retrieve information about the study episode.
Longitudinal association between hippocampus atrophy and episodic-memory decline.

PubMed

Gorbach, Tetiana; Pudas, Sara; Lundquist, Anders; Orädd, Greger; Josefsson, Maria; Salami, Alireza; de Luna, Xavier; Nyberg, Lars

2017-03-01

There is marked variability in both onset and rate of episodic-memory decline in aging. Structural magnetic resonance imaging studies have revealed that the extent of age-related brain changes varies markedly across individuals. Past studies of whether regional atrophy accounts for episodic-memory decline in aging have yielded inconclusive findings. Here we related 15-year changes in episodic memory to 4-year changes in cortical and subcortical gray matter volume and in white-matter connectivity and lesions. In addition, changes in word fluency, fluid IQ (Block Design), and processing speed were estimated and related to structural brain changes. Significant negative change over time was observed for all cognitive and brain measures. A robust brain-cognition change-change association was observed for episodic-memory decline and atrophy in the hippocampus. This association was significant for older (65-80 years) but not middle-aged (55-60 years) participants and not sensitive to the assumption of ignorable attrition. Thus, these longitudinal findings highlight medial-temporal lobe system integrity as particularly crucial for maintaining episodic-memory functioning in older age. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
A Time and Place for Everything: Developmental Differences in the Building Blocks of Episodic Memory

PubMed Central

Lee, Joshua K.; Wendelken, J. Carter; Bunge, Silvia A.; Ghetti, Simona

2015-01-01

This research investigated whether episodic memory development can be explained by improvements in relational binding processes, involved in forming novel associations between events and the context in which they occurred. Memory for item-space, item-time, and item-item relations was assessed in an ethnically diverse sample of 151 children aged 7 to 11 years and 28 young adults. Item-space memory reached adult performance by 9½ years, whereas item-time and item-item memory improved into adulthood. In path analysis, item-space, but not item-time best explained item-item memory. Across age groups, relational binding related to source memory and performance on standardized memory assessments. In conclusion, relational binding development depends on relation type, but relational binding overall supports episodic memory development. PMID:26493950

Autobiographical memory and patterns of brain atrophy in frontotemporal lobar degeneration.

PubMed

McKinnon, Margaret C; Nica, Elena I; Sengdy, Pheth; Kovacevic, Natasa; Moscovitch, Morris; Freedman, Morris; Miller, Bruce L; Black, Sandra E; Levine, Brian

2008-10-01

Autobiographical memory paradigms have been increasingly used to study the behavioral and neuroanatomical correlates of human remote memory. Although there are numerous functional neuroimaging studies on this topic, relatively few studies of patient samples exist, with heterogeneity of results owing to methodological variability. In this study, fronto-temporal lobar degeneration (FTLD), a form of dementia affecting regions crucial to autobiographical memory, was used as a model of autobiographical memory loss. We emphasized the separation of episodic (recollection of specific event, perceptual, and mental state information) from semantic (factual information unspecific in time and place) autobiographical memory, derived from a reliable method for scoring transcribed autobiographical protocols, the Autobiographical Interview [Levine, B., Svoboda, E., Hay, J., Winocur, G., & Moscovitch, M. Aging and autobiographical memory: Dissociating episodic from semantic retrieval. Psychology and Aging, 17, 677-689, 2002]. Patients with the fronto-temporal dementia (FTD) and mixed fronto-temporal and semantic dementia (FTD/SD) variants of FTLD were impaired at reconstructing episodically rich autobiographical memories across the lifespan, with FTD/SD patients generating an excess of generic semantic autobiographical information. Patients with progressive nonfluent aphasia were mildly impaired for episodic autobiographical memory, but this impairment was eliminated with the provision of structured cueing, likely reflecting relatively intact medial-temporal lobe function, whereas the same cueing failed to bolster the FTD and FTD/SD patients' performance relative to that of matched comparison subjects. The pattern of episodic, but not semantic, autobiographical impairment was enhanced with disease progression on 1- to 2-year follow-up testing in a subset of patients, supplementing the cross-sectional evidence for specificity of episodic autobiographical impairment with longitudinal data. This behavioral pattern covaried with volume loss in a distributed left-lateralized posterior network centered on the temporal lobe, consistent with evidence from other patient and functional neuroimaging studies of autobiographical memory. Frontal lobe volumes, however, did not significantly contribute to this network, suggesting that frontal contributions to autobiographical episodic memory may be more complex than previously appreciated.
Sleep-dependent consolidation patterns reveal insights into episodic memory structure.

PubMed

Oyanedel, Carlos N; Sawangjit, Anuck; Born, Jan; Inostroza, Marion

2018-05-18

Episodic memory formation is considered a genuinely hippocampal function. Its study in rodents has relied on two different task paradigms, i.e. the so called "what-where-when" (WW-When) task and "what-where-which" (WW-Which) task. The WW-When task aims to assess the memory for an episode as an event bound into its context defined by spatial and distinct temporal information, the WW-Which task lacks the temporal component and introduces, instead, an "occasion setter" marking the broader contextual configuration in which the event occurred. Whether both tasks measure episodic memory in an equivalent manner in terms of recollection has been controversially discussed. Here, we compared in two groups of rats the consolidating effects of sleep on episodic-like memory between both task paradigms. Sampling and test phases were separated by a 90-min morning retention interval which did or did not allow for spontaneous sleep. Results show that sleep is crucial for the consolidation of the memory on both tasks. However, consolidating effects of sleep were stronger for the WW-Which than WW-When task. Comparing performance during the post-sleep test phase revealed that WW-When memory only gradually emerged during the 3-min test period whereas WW-Which memory was readily expressed already from the first minute onward. Separate analysis of the temporal and spatial components of WW-When performance showed that the delayed episodic memory on this task originated from the temporal component which also did not emerge until the third minute of the test phase, whereas the spatial component already showed up in the first minute. In conclusion, sleep differentially affects consolidation on the two episodic-like memory tasks, with the delayed expression of WW-When memory after sleep resulting from preferential coverage of temporal aspects by this task. Copyright © 2018. Published by Elsevier Inc.
Cellular dynamical mechanisms for encoding the time and place of events along spatiotemporal trajectories in episodic memory.

PubMed

Hasselmo, Michael E; Giocomo, Lisa M; Brandon, Mark P; Yoshida, Motoharu

2010-12-31

Understanding the mechanisms of episodic memory requires linking behavioral data and lesion effects to data on the dynamics of cellular membrane potentials and population interactions within brain regions. Linking behavior to specific membrane channels and neurochemicals has implications for therapeutic applications. Lesions of the hippocampus, entorhinal cortex and subcortical nuclei impair episodic memory function in humans and animals, and unit recording data from these regions in behaving animals indicate episodic memory processes. Intracellular recording in these regions demonstrates specific cellular properties including resonance, membrane potential oscillations and bistable persistent spiking that could underlie the encoding and retrieval of episodic trajectories. A model presented here shows how intrinsic dynamical properties of neurons could mediate the encoding of episodic memories as complex spatiotemporal trajectories. The dynamics of neurons allow encoding and retrieval of unique episodic trajectories in multiple continuous dimensions including temporal intervals, personal location, the spatial coordinates and sensory features of perceived objects and generated actions, and associations between these elements. The model also addresses how cellular dynamics could underlie unit firing data suggesting mechanisms for coding continuous dimensions of space, time, sensation and action. Copyright © 2010 Elsevier B.V. All rights reserved.
Cellular dynamical mechanisms for encoding the time and place of events along spatiotemporal trajectories in episodic memory

PubMed Central

Hasselmo, Michael E.; Giocomo, Lisa M.; Yoshida, Motoharu

2010-01-01

Understanding the mechanisms of episodic memory requires linking behavioural data and lesion effects to data on the dynamics of cellular membrane potentials and population interactions within these brain regions. Linking behavior to specific membrane channels and neurochemicals has implications for therapeutic applications. Lesions of the hippocampus, entorhinal cortex and subcortical nuclei impair episodic memory function in humans and animals, and unit recording data from these regions in behaving animals indicate episodic memory processes. Intracellular recording in these regions demonstrates specific cellular properties including resonance, membrane potential oscillations and bistable persistent spiking that could underlie the encoding and retrieval of episodic trajectories. A model presented here shows how intrinsic dynamical properties of neurons could mediate the encoding of episodic memories as complex spatiotemporal trajectories. The dynamics of neurons allow encoding and retrieval of unique episodic trajectories in multiple continuous dimensions including temporal intervals, personal location, the spatial coordinates and sensory features of perceived objects and generated actions, and associations between these elements. The model also addresses how cellular dynamics could underlie unit firing data suggesting mechanisms for coding continuous dimensions of space, time, sensation and action. PMID:20018213
Job strain and trajectories of change in episodic memory before and after retirement: results from the Health and Retirement Study.

PubMed

Andel, Ross; Infurna, Frank J; Hahn Rickenbach, Elizabeth A; Crowe, Michael; Marchiondo, Lisa; Fisher, Gwenith G

2015-05-01

We examined indicators of job strain in relation to level and change in episodic memory in the years leading up to as well as following retirement. Our analyses centre on 3779 individuals from the nationally representative Health and Retirement Study (baseline age 57.3 years) who reported gainful employment in an occupation for 10+ years prior to retirement, and who were assessed for episodic memory performance over up to 20 years (median 8 waves over 16 years). We used ratings from the Occupational Information Network (O*Net) to score occupations for job control and job demands, and to measure job strain (job demands/job control). Controlling for sociodemographic characteristics, depressive symptoms, and cardiovascular disease, less job control and greater job strain were not significantly associated with change in episodic memory in the period leading up to retirement, but were associated with significantly poorer episodic memory at retirement and an accelerated rate of decline in episodic memory following retirement. The results did not vary for men and women or by self-employment status. Job strain expressed mainly as low job control is linked to poorer episodic memory at retirement and more decline after retirement. Job characteristics appear to have implications for cognitive ageing independent of relevant confounds. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Distinct neuroanatomical bases of episodic and semantic memory performance in Alzheimer's disease.

PubMed

Hirni, Daniela I; Kivisaari, Sasa L; Monsch, Andreas U; Taylor, Kirsten I

2013-04-01

Alzheimer's disease (AD) neurofibrillary pathology begins in the medial perirhinal cortex (mPRC) before spreading to the entorhinal cortex (ERC) and hippocampus (HP) in anterior medial temporal lobe (aMTL). While the role of the ERC/HP complex in episodic memory formation is well-established, recent research suggests that the PRC is required to form semantic memories of individual objects. We aimed to test whether commonly used clinical measures of episodic and semantic memory are distinctly associated with ERC/HP and mPRC integrity, respectively, in healthy mature individuals and very early AD patients. One hundred thirty normal controls, 32 amnestic mild cognitive impairment patients, some of whom are in the earliest (i.e., preclinical) stages of AD, and ten early-stage AD patients received neuropsychological testing and high-resolution anatomic and diffusion MRI. Voxel-based regression analyses tested for regions where episodic memory (delayed recall scores on the California Verbal Learning and Rey Osterrieth Complex Figure Tests) and semantic memory (Boston Naming Test, category fluency) performance correlated with gray matter (GM) regions of interest and whole-brain fractional anisotropy (FA) voxel values. When controlling for the opposing memory performance, poorer episodic memory performance was associated with reduced bilateral ERC/HP GM volume and related white matter integrity, but not with mPRC GM volume. Poor semantic memory performance was associated with both reduced left mPRC and ERC/HP GM volume, as well as reduced FA values in white matter tracts leading to the PRC. These results indicate a partial division of labor within the aMTL and suggest that mPRC damage in very early AD may be detectable with common clinical tests of semantic memory if episodic memory performance is controlled. Copyright © 2013 Elsevier Ltd. All rights reserved.
The effects of aging on emotion-induced modulations of source retrieval ERPs: evidence for valence biases.

PubMed

Newsome, Rachel N; Dulas, Michael R; Duarte, Audrey

2012-12-01

Many behavioral studies have shown that memory is enhanced for emotionally salient events across the lifespan. It has been suggested that this mnemonic boost may be observed for both age groups, particularly the old, in part because emotional information is retrieved with less effort than neutral information. Neuroimaging evidence suggests that inefficient retrieval processing (temporally delayed and attenuated) may contribute to age-related impairments in episodic memory for neutral events. It is not entirely clear whether emotional salience may reduce these age-related changes in neural activity associated with episodic retrieval for neutral events. Here, we investigated these ideas using event-related potentials (ERPs) to assess the neural correlates of successful source memory retrieval ("old-new effects") for neutral and emotional (negative and positive) images. Behavioral results showed that older adults demonstrated source memory impairments compared to the young but that both groups showed reduced source memory accuracy for negative compared to positive and neutral images; most likely due to an arousal-induced memory tradeoff for the negative images, which were subjectively more arousing than both positive and neutral images. ERP results showed that early onsetting old-new effects, between 100 and 300 ms, were observed for emotional but not neutral images in both age groups. Interestingly, these early effects were observed for negative items in the young and for positive items in the old. These ERP findings offer support for the idea that emotional events may be retrieved more automatically than neutral events across the lifespan. Furthermore, we suggest that very early retrieval mechanisms, possibly perceptual priming or familiarity, may underlie the negativity and positivity effects sometimes observed in the young and old, respectively, for various behavioral measures of attention and memory. Copyright © 2012 Elsevier Ltd. All rights reserved.
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
Reconsolidation of Episodic Memories: A Subtle Reminder Triggers Integration of New Information

ERIC Educational Resources Information Center

Hupbach, Almut; Gomez, Rebecca; Hardt, Oliver; Nadel, Lynn

2007-01-01

Recent demonstrations of "reconsolidation" suggest that memories can be modified when they are reactivated. Reconsolidation has been observed in human procedural memory and in implicit memory in infants. This study asks whether episodic memory undergoes reconsolidation. College students learned a list of objects on Day 1. On Day 2, they received a…
The effects of rehearsal on the functional neuroanatomy of episodic autobiographical and semantic remembering: an fMRI study

PubMed Central

Svoboda, Eva; Levine, Brian

2009-01-01

This study examined the effects of rehearsal on the neural substrates supporting episodic autobiographical and semantic memory. Stimuli were collected prospectively using audio recordings, thereby bringing under experimental control ecologically-valid, naturalistic autobiographical stimuli. Participants documented both autobiographical and semantic stimuli over a period of 6 to 8 months, followed by a rehearsal manipulation during the three days preceding scanning. During fMRI scanning participants were exposed to recordings that they were hearing for the first, second or eighth time. Rehearsal increased the rated vividness with which information was remembered, particularly for autobiographical events. Neuroimaging findings revealed rehearsal-related suppression of activation in regions supporting episodic autobiographical and semantic memory. Episodic autobiographical and semantic memory produced distinctly different patterns of regional activation that held even after eight repetitions. Region of interest analyses further indicated a functional anatomical dissociation in response to rehearsal and memory conditions. These findings revealed that the hippocampus was specifically engaged by episodic autobiographical memory, whereas both memory conditions engaged the parahippocampal cortex. Our data suggest that when retrieval cues are potent enough to engage a vivid episodic recollection, the episodic/semantic dissociation within medial temporal lobe structures endure even with multiple stimulus repetitions. These findings support the Multiple Trace Theory (MTT) which predicts that the hippocampus is engaged in the retrieval of rich episodic recollection regardless of repeated reactivation such as that occurring with the passage of time. PMID:19279244
The effects of rehearsal on the functional neuroanatomy of episodic autobiographical and semantic remembering: a functional magnetic resonance imaging study.

PubMed

Svoboda, Eva; Levine, Brian

2009-03-11

This study examined the effects of rehearsal on the neural substrates supporting episodic autobiographical and semantic memory. Stimuli were collected prospectively using audio recordings, thereby bringing under experimental control ecologically valid, naturalistic autobiographical stimuli. Participants documented both autobiographical and semantic stimuli over a period of 6-8 months, followed by a rehearsal manipulation during the 3 d preceding scanning. During functional magnetic resonance imaging scanning, participants were exposed to recordings that they were hearing for the first, second, or eighth time. Rehearsal increased the rated vividness with which information was remembered, particularly for autobiographical events. Neuroimaging findings revealed rehearsal-related suppression of activation in regions supporting episodic autobiographical and semantic memory. Episodic autobiographical and semantic memory produced distinctly different patterns of regional activation that held even after eight repetitions. Region of interest analyses further indicated a functional anatomical dissociation in response to rehearsal and memory conditions. These findings revealed that the hippocampus was specifically engaged by episodic autobiographical memory, whereas both memory conditions engaged the parahippocampal cortex. Our data suggest that, when retrieval cues are potent enough to engage a vivid episodic recollection, the episodic/semantic dissociation within medial temporal lobe structures endure even with multiple stimulus repetitions. These findings support the multiple trace theory, which predicts that the hippocampus is engaged in the retrieval of rich episodic recollection regardless of repeated reactivation such as that occurring with the passage of time.
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.
Does the greater involvement of executive control in memory with age act as a compensatory mechanism?

PubMed

Bouazzaoui, Badiâa; Angel, Lucie; Fay, Séverine; Taconnat, Laurence; Charlotte, Froger; Isingrini, Michel

2014-03-01

Recent behavioural and imaging data have shown that memory functioning seems to rely more on executive functions and on the prefrontal cortex (PFC) in older than in young adults. Using a behavioural approach, our objective was to confirm the hypothesis that young and older adults present different patterns of correlation between episodic memory performance and executive functioning. We report three studies comparing the correlations of young and older adults in a broad range of episodic memory and executive function tasks. The results indicated that memory and executive performance were consistently and significantly correlated in older but not in younger adults. Regression analyses confirmed that age-related differences in episodic memory performance could be explained by individual differences in executive functioning. The results are consistent with the view that memory functioning in aging is accompanied by a shift from automatic to controlled forms of processing. They also generalise the executive hypothesis of episodic memory aging and are in line with the idea that executive functions act as a compensatory mechanism against age-related memory decline.
Episodic Memory and Episodic Future Thinking Impairments in High-Functioning Autism Spectrum Disorder: An Underlying Difficulty With Scene Construction or Self-Projection?

PubMed Central

2013-01-01

Objective: There appears to be a common network of brain regions that underlie the ability to recall past personal experiences (episodic memory) and the ability to imagine possible future personal experiences (episodic future thinking). At the cognitive level, these abilities are thought to rely on “scene construction” (the ability to bind together multimodal elements of a scene in mind—dependent on hippocampal functioning) and temporal “self-projection” (the ability to mentally project oneself through time—dependent on prefrontal cortex functioning). Although autism spectrum disorder (ASD) is characterized by diminished episodic memory, it is unclear whether episodic future thinking is correspondingly impaired. Moreover, the underlying basis of such impairments (difficulties with scene construction, self-projection, or both) is yet to be established. The current study therefore aimed to elucidate these issues. Method: Twenty-seven intellectually high-functioning adults with ASD and 29 age- and IQ-matched neurotypical comparison adults were asked to describe (a) imagined atemporal, non-self-relevant fictitious scenes (assessing scene construction), (b) imagined plausible self-relevant future episodes (assessing episodic future thinking), and (c) recalled personally experienced past episodes (assessing episodic memory). Tests of narrative ability and theory of mind were also completed. Results: Performances of participants with ASD were significantly and equally diminished in each condition and, crucially, this diminution was independent of general narrative ability. Conclusions: Given that participants with ASD were impaired in the fictitious scene condition, which does not involve self-projection, we suggest the underlying difficulty with episodic memory/future thinking is one of scene construction. PMID:24015827
Episodic memory and episodic future thinking impairments in high-functioning autism spectrum disorder: an underlying difficulty with scene construction or self-projection?

PubMed

Lind, Sophie E; Williams, David M; Bowler, Dermot M; Peel, Anna

2014-01-01

There appears to be a common network of brain regions that underlie the ability to recall past personal experiences (episodic memory) and the ability to imagine possible future personal experiences (episodic future thinking). At the cognitive level, these abilities are thought to rely on "scene construction" (the ability to bind together multimodal elements of a scene in mind--dependent on hippocampal functioning) and temporal "self-projection" (the ability to mentally project oneself through time--dependent on prefrontal cortex functioning). Although autism spectrum disorder (ASD) is characterized by diminished episodic memory, it is unclear whether episodic future thinking is correspondingly impaired. Moreover, the underlying basis of such impairments (difficulties with scene construction, self-projection, or both) is yet to be established. The current study therefore aimed to elucidate these issues. Twenty-seven intellectually high-functioning adults with ASD and 29 age- and IQ-matched neurotypical comparison adults were asked to describe (a) imagined atemporal, non-self-relevant fictitious scenes (assessing scene construction), (b) imagined plausible self-relevant future episodes (assessing episodic future thinking), and (c) recalled personally experienced past episodes (assessing episodic memory). Tests of narrative ability and theory of mind were also completed. Performances of participants with ASD were significantly and equally diminished in each condition and, crucially, this diminution was independent of general narrative ability. Given that participants with ASD were impaired in the fictitious scene condition, which does not involve self-projection, we suggest the underlying difficulty with episodic memory/future thinking is one of scene construction.
Structural and Metabolic Correlates of Episodic Memory in Relation to the Depth of Encoding in Normal Aging

ERIC Educational Resources Information Center

Kalpouzos, Gregoria; Chetelat, Gael; Landeau, Brigitte; Clochon, Patrice; Viader, Fausto; Eustache, Francis; Desgranges, Beatrice

2009-01-01

This study set out to establish the relationship between changes in episodic memory retrieval in normal aging on the one hand and gray matter volume and [superscript 18]FDG uptake on the other. Structural MRI, resting-state [superscript 18]FDG-PET, and an episodic memory task manipulating the depth of encoding and the retention interval were…
Temporal compression in episodic memory for real-life events.

PubMed

Jeunehomme, Olivier; Folville, Adrien; Stawarczyk, David; Van der Linden, Martial; D'Argembeau, Arnaud

2018-07-01

Remembering an event typically takes less time than experiencing it, suggesting that episodic memory represents past experience in a temporally compressed way. Little is known, however, about how the continuous flow of real-life events is summarised in memory. Here we investigated the nature and determinants of temporal compression by directly comparing memory contents with the objective timing of events as measured by a wearable camera. We found that episodic memories consist of a succession of moments of prior experience that represent events with varying compression rates, such that the density of retrieved information is modulated by goal processing and perceptual changes. Furthermore, the results showed that temporal compression rates remain relatively stable over one week and increase after a one-month delay, particularly for goal-related events. These data shed new light on temporal compression in episodic memory and suggest that compression rates are adaptively modulated to maintain current goal-relevant information.
Episodic-like memory in zebrafish.

PubMed

Hamilton, Trevor J; Myggland, Allison; Duperreault, Erika; May, Zacnicte; Gallup, Joshua; Powell, Russell A; Schalomon, Melike; Digweed, Shannon M

2016-11-01

Episodic-like memory tests often aid in determining an animal's ability to recall the what, where, and which (context) of an event. To date, this type of memory has been demonstrated in humans, wild chacma baboons, corvids (Scrub jays), humming birds, mice, rats, Yucatan minipigs, and cuttlefish. The potential for this type of memory in zebrafish remains unexplored even though they are quickly becoming an essential model organism for the study of a variety of human cognitive and mental disorders. Here we explore the episodic-like capabilities of zebrafish (Danio rerio) in a previously established mammalian memory paradigm. We demonstrate that when zebrafish were presented with a familiar object in a familiar context but a novel location within that context, they spend more time in the novel quadrant. Thus, zebrafish display episodic-like memory as they remember what object they saw, where they saw it (quadrant location), and on which occasion (yellow or blue walls) it was presented.
Intake of Wild Blueberry Powder Improves Episodic-Like and Working Memory during Normal Aging in Mice.

PubMed

Beracochea, Daniel; Krazem, Ali; Henkouss, Nadia; Haccard, Guillaume; Roller, Marc; Fromentin, Emilie

2016-08-01

The number of Americans older than 65 years old is projected to more than double in the next 40 years. Cognitive changes associated to aging can affect an adult's day-to-day functioning. Among these cognitive changes, reasoning, episodic memory, working memory, and processing speed decline gradually over time. Early memory changes include a decline in both working and episodic memory. The aim of the present study was to determine whether chronic (up to 75 days) daily administration of wild blueberry extract or a wild blueberry full spectrum powder would help prevent memory failure associated with aging in tasks involving various forms of memory. Both blueberry ingredients were used in a study comparing young mice (6 months old) to aged mice (18 months old). At this age, mice exhibit memory decline due to aging, which is exacerbated first by a loss in working and contextual (episodic-like) memory. Contextual memory (episodic-like memory) was evaluated using the contextual serial discrimination test. Working and spatial memory were evaluated using the Morris-Water maze test and the sequential alternation test. Statistical analysis was performed using an ANOVA with the Bonferroni post-hoc test. Supplementation with wild blueberry full spectrum powder and wild blueberry extract resulted in significant improvement of contextual memory, while untreated aged mice experienced a decline in such memory. Only the wild blueberry full spectrum powder significantly contributed to an improvement of spatial and working memory versus untreated aged mice. These improvements of cognitive performance may be related to brain oxidative status, acetylcholinesterase activity, neuroprotection, or attenuation of immunoreactivity. Georg Thieme Verlag KG Stuttgart · New York.
The neural substrates of memory suppression: a FMRI exploration of directed forgetting.

PubMed

Bastin, Christine; Feyers, Dorothée; Majerus, Steve; Balteau, Evelyne; Degueldre, Christian; Luxen, André; Maquet, Pierre; Salmon, Eric; Collette, Fabienne

2012-01-01

The directed forgetting paradigm is frequently used to determine the ability to voluntarily suppress information. However, little is known about brain areas associated with information to forget. The present study used functional magnetic resonance imaging to determine brain activity during the encoding and retrieval phases of an item-method directed forgetting recognition task with neutral verbal material in order to apprehend all processing stages that information to forget and to remember undergoes. We hypothesized that regions supporting few selective processes, namely recollection and familiarity memory processes, working memory, inhibitory and selection processes should be differentially activated during the processing of to-be-remembered and to-be-forgotten items. Successful encoding and retrieval of items to remember engaged the entorhinal cortex, the hippocampus, the anterior medial prefrontal cortex, the left inferior parietal cortex, the posterior cingulate cortex and the precuneus; this set of regions is well known to support deep and associative encoding and retrieval processes in episodic memory. For items to forget, encoding was associated with higher activation in the right middle frontal and posterior parietal cortex, regions known to intervene in attentional control. Items to forget but nevertheless correctly recognized at retrieval yielded activation in the dorsomedial thalamus, associated with familiarity-based memory processes and in the posterior intraparietal sulcus and the anterior cingulate cortex, involved in attentional processes.

Some links on this page may take you to non-federal websites. Their policies may differ from this site.