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Sample records for individual episodic memory

  1. 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…

  2. 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.

  3. Cannabis-related episodic memory deficits and hippocampal morphological differences in healthy individuals and schizophrenia subjects.

    PubMed

    Smith, Matthew J; Cobia, Derin J; Reilly, James L; Gilman, Jodi M; Roberts, Andrea G; Alpert, Kathryn I; Wang, Lei; Breiter, Hans C; Csernansky, John G

    2015-09-01

    Cannabis use has been associated with episodic memory (EM) impairments and abnormal hippocampus morphology among both healthy individuals and schizophrenia subjects. Considering the hippocampus' role in EM, research is needed to evaluate the relationship between cannabis-related hippocampal morphology and EM among healthy and clinical groups. We examined differences in hippocampus morphology between control and schizophrenia subjects with and without a past (not current) cannabis use disorder (CUD). Subjects group-matched on demographics included 44 healthy controls (CON), 10 subjects with a CUD history (CON-CUD), 28 schizophrenia subjects with no history of substance use disorders (SCZ), and 15 schizophrenia subjects with a CUD history (SCZ-CUD). Large-deformation, high-dimensional brain mapping with MRI produced surface-based representations of the hippocampus that were compared across all four groups and correlated with EM and CUD history. Surface maps of the hippocampus were generated to visualize morphological differences. CON-CUD and SCZ-CUD were characterized by distinct cannabis-related hippocampal shape differences and parametric deficits in EM performance. Shape differences observed in CON-CUD were associated with poorer EM performance, while shape differences observed in SCZ-CUD were associated with a longer duration of CUD and shorter duration of CUD remission. A past history of CUD may be associated with notable differences in hippocampal morphology and EM impairments among adults with and without schizophrenia. Although the results may be compatible with a causal hypothesis, we must consider that the observed cannabis-related shape differences in the hippocampus could also be explained as biomarkers of a neurobiological susceptibility to poor memory or the effects of cannabis.

  4. The precuneus and hippocampus contribute to individual differences in the unfolding of spatial representations during episodic autobiographical memory.

    PubMed

    Hebscher, Melissa; Levine, Brian; Gilboa, Asaf

    2017-03-30

    Spatial information is a central aspect of episodic autobiographical memory (EAM). Space-based theories of memory, including cognitive map and scene construction models, posit that spatial reinstatement is a required process during early event recall. Spatial information can be represented from both allocentric (third-person) and egocentric (first-person) perspectives during EAM, with egocentric perspectives being important for mental imagery and supported by the precuneus. Individuals differ in their tendency to rely on allocentric or egocentric information, and in general, the subjective experience of remembering in EAM differs greatly across individuals. Here we examined individual differences in spatial aspects of EAM, how such differences influence the vividness and temporal order of recollection, and their anatomical correlates. We cued healthy young participants (n =63) with personally familiar locations and non-locations. We examined how cue type affects (i) retrieval dynamics and (ii) phenomenological aspects of remembering, and related behavioural performance to regional brain volumes (n =42). Participants tended to spontaneously recall spatial information early during recollection, even in the absence of spatial cues, and individuals with a stronger tendency to recall space first also displayed faster reaction times. Across participants, place-cued memories were re-experienced more vividly and were richer in detail than those cued by objects, but not more than those cued by familiar persons. Volumetric differences were associated with behavioural performance such that egocentric remembering was positively associated with precuneus volume. Hippocampal CA2/CA3 volumes were associated with the tendency to recall place-cued memories less effortfully. Consistent with scene construction theories, this study suggests that spatial information is reinstated early and contributes to the efficiency and phenomenology of EAM. However, early recall of spatial

  5. Gender differences in episodic memory.

    PubMed

    Herlitz, A; Nilsson, L G; Bäckman, L

    1997-11-01

    The relationship between gender and memory has been largely neglected by research, despite occasional studies reporting gender differences in episodic memory performance. The present study examined potential gender differences in episodic memory, semantic memory, primary memory, and priming. Five hundred thirty women and 470 men, randomly sampled from the city of Umeå, Sweden, 35-80 years of age, participated in the study. There were no differences between men and women with regard to age or education, or on a measure of global intellectual functioning. As has been demonstrated previously, men out performed women on a visuospatial task and women outperformed men on tests of verbal fluency. In addition, the results demonstrated that women consistently performed at a higher level than did men on the episodic memory tasks, although there were no differences between men and women on the tasks assessing semantic memory, primary memory, or priming. The women's higher level of performance on the episodic memory tasks could not be fully explained by their higher verbal ability.

  6. 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

  7. 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

  8. Individual Differences in Working Memory Capacity and Episodic Retrieval: Examining the Dynamics of Delayed and Continuous Distractor Free Recall

    ERIC Educational Resources Information Center

    Unsworth, Nash

    2007-01-01

    Two experiments explored the possibility that individual differences in working memory capacity (WMC) partially reflect differences in the size of the search set from which items are retrieved. High- and low-WMC individuals were tested in delayed (Experiment 1) and continuous distractor (Experiment 2) free recall with varying list lengths. Across…

  9. Predicting episodic memory formation for movie events

    PubMed Central

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

    2016-01-01

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

  10. 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…

  11. 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

  12. 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…

  13. Episodic Memory and Episodic Foresight in 3- and 5-Year-Old Children

    ERIC Educational Resources Information Center

    Hayne, Harlene; Gross, Julien; McNamee, Stephanie; Fitzgibbon, Olivia; Tustin, Karen

    2011-01-01

    In the present study, we examined the development of episodic memory and episodic foresight. Three- and 5-year-olds were interviewed individually using a personalised timeline that included photographs of them at different points in their life. After constructing the timeline with the experimenter, each child was asked to discuss a number of…

  14. Episodic memories predict adaptive value-based decision-making.

    PubMed

    Murty, Vishnu P; FeldmanHall, Oriel; Hunter, Lindsay E; Phelps, Elizabeth A; Davachi, Lila

    2016-05-01

    Prior research illustrates that memory can guide value-based decision-making. For example, previous work has implicated both working memory and procedural memory (i.e., reinforcement learning) in guiding choice. However, other types of memories, such as episodic memory, may also influence decision-making. Here we test the role for episodic memory-specifically item versus associative memory-in supporting value-based choice. Participants completed a task where they first learned the value associated with trial unique lotteries. After a short delay, they completed a decision-making task where they could choose to reengage with previously encountered lotteries, or new never before seen lotteries. Finally, participants completed a surprise memory test for the lotteries and their associated values. Results indicate that participants chose to reengage more often with lotteries that resulted in high versus low rewards. Critically, participants not only formed detailed, associative memories for the reward values coupled with individual lotteries, but also exhibited adaptive decision-making only when they had intact associative memory. We further found that the relationship between adaptive choice and associative memory generalized to more complex, ecologically valid choice behavior, such as social decision-making. However, individuals more strongly encode experiences of social violations-such as being treated unfairly, suggesting a bias for how individuals form associative memories within social contexts. Together, these findings provide an important integration of episodic memory and decision-making literatures to better understand key mechanisms supporting adaptive behavior.

  15. The case for episodic memory in animals.

    PubMed

    Dere, E; Kart-Teke, E; Huston, J P; De Souza Silva, M A

    2006-01-01

    The conscious recollection of unique personal experiences in terms of their details (what), their locale (where) and temporal occurrence (when) is known as episodic memory and is thought to require a 'self-concept', autonoetic awareness/conciousness, and the ability to subjectively sense time. It has long been held that episodic memory is unique to humans, because it was accepted that animals lack a 'self-concept', 'autonoetic awareness', and the ability to 'subjectively sense time'. These assumptions are now being questioned by behavioral evidence showing that various animal species indeed show behavioral manifestations of different features of episodic memory such as, e.g. 'metacognition', 'conscious recollection' of past events, 'temporal order memory', 'mental time travel' and have the capacity to remember personal experiences in terms of what happened, where and when. The aim of this review is to provide a comprehensive overview on the current progress in attempts to model different prerequisites and features of human episodic memory in animals and to identify possible neural substrates of animal episodic memory. The literature covered includes behavioral and physiological studies performed with different animal species, such as non-human primates, rodents, dolphins and birds. The search for episodic memory in animals has forced researchers to define objective behavioral criteria by which different features of episodic memory can be operationalized experimentally and assessed in both animals and humans. This is especially important because the current definition of episodic memory in terms of mentalistic constructs such as 'self', 'autonoetic awareness/consciousness', and 'subjectively sensed time', not only hinders animal research on the neurobiology of episodic memory but also research with healthy human subjects as well as neuropsychiatric patients with impaired language or in children with less-developed verbal abilities.

  16. Hippocampal place cells, context, and episodic memory.

    PubMed

    Smith, David M; Mizumori, Sheri J Y

    2006-01-01

    Although most observers agree that the hippocampus has a critical role in learning and memory, there remains considerable debate about the precise functional contribution of the hippocampus to these processes. Two of the most influential accounts hold that the primary function of the hippocampus is to generate cognitive maps and to mediate episodic memory processes. The well-documented spatial firing patterns (place fields) of hippocampal neurons in rodents, along with the spatial learning impairments observed with hippocampal damage support the cognitive mapping hypothesis. The amnesia for personally experienced events seen in humans with hippocampal damage and the data of animal models, which show severe memory deficits associated with hippocampal lesions, support the episodic memory account. Although an extensive literature supports each of these hypotheses, a specific contribution of place cells to episodic memory has not been clearly demonstrated. Recent data from our laboratory, together with previous findings, indicate that hippocampal place fields and neuronal responses to task-relevant stimuli are highly sensitive to the context, even when the contexts are defined by abstract task demands rather than the spatial geometry of the environment. On the basis of these findings, it is proposed that place fields reflect a more general context processing function of the hippocampus. Hippocampal context representations could serve to differentiate contexts and prime the relevant memories and behaviors. Since episodic memories, by definition, include information about the time and place where the episode occurred, contextual information is a necessary prerequisite for any episodic memory. Thus, place fields contribute importantly to episodic memory as part of the needed context representations. Additionally, recent findings indicate that hippocampal neurons differentiate contexts at progressively finer levels of detail, suggesting a hierarchical coding scheme which

  17. 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

  18. Stroke and Episodic Memory Disorders

    ERIC Educational Resources Information Center

    Lim, Chun; Alexander, Michael P.

    2009-01-01

    Memory impairments are common after stroke, and the anatomical basis for impairments may be quite variable. To determine the range of stroke-related memory impairment, we identified all case reports and group studies through the Medline database and the Science Citation Index. There is no hypothesis about memory that is unique to stroke, but there…

  19. 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

  20. Stroke and episodic memory disorders.

    PubMed

    Lim, Chun; Alexander, Michael P

    2009-12-01

    Memory impairments are common after stroke, and the anatomical basis for impairments may be quite variable. To determine the range of stroke-related memory impairment, we identified all case reports and group studies through the Medline database and the Science Citation Index. There is no hypothesis about memory that is unique to stroke, but there are several important facets of memory impairment after stroke: (1) Every node of the limbic system implicated in memory may be damaged by stroke but very rarely in isolation and the combination of amnesia with the associated deficits often illuminates additional aspects of memory functions. (2) Stroke produces amnesia by damage to critical convergence white matter connections of the limbic system, and stroke is the only etiology of amnesia that can delineate the entire pathway of memory and critical convergence points. (3) Stroke also impairs memory, without causing classical amnesia, by damaging brain regions responsible for cognitive processes, some modality specific and some more generally strategic, that are essential for normal learning and recall.

  1. Imagining the personal past: Episodic counterfactuals compared to episodic memories and episodic future projections.

    PubMed

    Özbek, Müge; Bohn, Annette; Berntsen, Dorthe

    2017-04-01

    Episodic counterfactuals are imagined events that could have happened, but did not happen, in a person's past. Such imagined past events are important aspects of mental life, affecting emotions, decisions, and behaviors. However, studies examining their phenomenological characteristics and content have been few. Here we introduced a new method to systematically compare self-generated episodic counterfactuals to self-generated episodic memories and future projections with regard to their phenomenological characteristics (e.g., imagery, emotional valence, and rehearsal) and content (e.g., reference to a cultural life script), and how these were affected by temporal distance (1 month, 1 year, 5+ years). The findings showed that the three types of events differed phenomenologically. First, episodic memories were remembered more easily, with more sensory details, and from a dominantly field perspective, as compared to both future projections and episodic counterfactuals. Second, episodic future projections were more positive, more voluntarily rehearsed, and more central to life story and identity than were both episodic memories and episodic counterfactuals. Third, episodic counterfactuals differed from both episodic memories and future projections by neither having the positivity bias of the future events nor the enhanced sensory details of the past events. Across all three event types, sensory details decreased, whereas importance, reference to a cultural life script, and centrality increased with increasing temporal distance. The findings show that imagined events are phenomenologically different from memories of experienced events, consistent with reality-monitoring theory, and that imagined future events are different from both actual and imagined past events, consistent with some theories of motivation.

  2. The Generalized Quantum Episodic Memory Model.

    PubMed

    Trueblood, Jennifer S; Hemmer, Pernille

    2016-12-21

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

  3. 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.

  4. Consolidation of temporal order in episodic memories

    PubMed Central

    Griessenberger, H.; Hoedlmoser, K.; Heib, D.P.J.; Lechinger, J.; Klimesch, W.; Schabus, M.

    2012-01-01

    Even though it is known that sleep benefits declarative memory consolidation, the role of sleep in the storage of temporal sequences has rarely been examined. Thus we explored the influence of sleep on temporal order in an episodic memory task followed by sleep or sleep deprivation. Thirty-four healthy subjects (17 men) aged between 19 and 28 years participated in the randomized, counterbalanced, between-subject design. Parameters of interests were NREM/REM cycles, spindle activity and spindle-related EEG power spectra. Participants of both groups (sleep group/sleep deprivation group) performed retrieval in the evening, morning and three days after the learning night. Results revealed that performance in temporal order memory significantly deteriorated over three days only in sleep deprived participants. Furthermore our data showed a positive relationship between the ratios of the (i) first NREM/REM cycle with more REM being associated with delayed temporal order recall. Most interestingly, data additionally indicated that (ii) memory enhancers in the sleep group show more fast spindle related alpha power at frontal electrode sites possibly indicating access to a yet to be consolidated memory trace. We suggest that distinct sleep mechanisms subserve different aspects of episodic memory and are jointly involved in sleep-dependent memory consolidation. PMID:22705480

  5. Cognitive dissonance resolution depends on episodic memory.

    PubMed

    Chammat, Mariam; Karoui, Imen El; Allali, Sébastien; Hagège, Joshua; Lehongre, Katia; Hasboun, Dominique; Baulac, Michel; Epelbaum, Stéphane; Michon, Agnès; Dubois, Bruno; Navarro, Vincent; Salti, Moti; Naccache, Lionel

    2017-01-23

    The notion that past choices affect preferences is one of the most influential concepts of social psychology since its first report in the 50 s, and its theorization within the cognitive dissonance framework. In the free-choice paradigm (FCP) after choosing between two similarly rated items, subjects reevaluate chosen items as more attractive and rejected items as less attractive. However the relations prevailing between episodic memory and choice-induced preference change (CIPC) remain highly debated: is this phenomenon dependent or independent from memory of past choices? We solve this theoretical debate by demonstrating that CIPC occurs exclusively for items which were correctly remembered as chosen or rejected during the choice stage. We used a combination of fMRI and intra-cranial electrophysiological recordings to reveal a modulation of left hippocampus activity, a hub of episodic memory retrieval, immediately before the occurrence of CIPC during item reevaluation. Finally, we show that contrarily to a previous influential report flawed by a statistical artifact, this phenomenon is absent in amnesic patients for forgotten items. These results demonstrate the dependence of cognitive dissonance on conscious episodic memory. This link between current preferences and previous choices suggests a homeostatic function of this regulative process, aiming at preserving subjective coherence.

  6. Cognitive dissonance resolution depends on episodic memory

    PubMed Central

    Chammat, Mariam; Karoui, Imen El; Allali, Sébastien; Hagège, Joshua; Lehongre, Katia; Hasboun, Dominique; Baulac, Michel; Epelbaum, Stéphane; Michon, Agnès; Dubois, Bruno; Navarro, Vincent; Salti, Moti; Naccache, Lionel

    2017-01-01

    The notion that past choices affect preferences is one of the most influential concepts of social psychology since its first report in the 50 s, and its theorization within the cognitive dissonance framework. In the free-choice paradigm (FCP) after choosing between two similarly rated items, subjects reevaluate chosen items as more attractive and rejected items as less attractive. However the relations prevailing between episodic memory and choice-induced preference change (CIPC) remain highly debated: is this phenomenon dependent or independent from memory of past choices? We solve this theoretical debate by demonstrating that CIPC occurs exclusively for items which were correctly remembered as chosen or rejected during the choice stage. We used a combination of fMRI and intra-cranial electrophysiological recordings to reveal a modulation of left hippocampus activity, a hub of episodic memory retrieval, immediately before the occurrence of CIPC during item reevaluation. Finally, we show that contrarily to a previous influential report flawed by a statistical artifact, this phenomenon is absent in amnesic patients for forgotten items. These results demonstrate the dependence of cognitive dissonance on conscious episodic memory. This link between current preferences and previous choices suggests a homeostatic function of this regulative process, aiming at preserving subjective coherence. PMID:28112261

  7. No association between CTNNBL1 and episodic memory performance.

    PubMed

    Liu, T; Li, S-C; Papenberg, G; Schröder, J; Roehr, J T; Nietfeld, W; Lindenberger, U; Bertram, L

    2014-09-30

    Polymorphisms in the gene encoding catenin-β-like 1 (CTNNBL1) were recently reported to be associated with verbal episodic memory performance--in particular, delayed verbal free recall assessed between 5 and 30 min after encoding--in a genome-wide association study on healthy young adults. To further examine the genetic effects of CTNNBL1, we tested for association between 455 single-nucleotide polymorphisms (SNPs) in or near CTNNBL1 and 14 measures of episodic memory performance from three different tasks in 1743 individuals. Probands were part of a population-based study of mentally healthy adult men and women, who were between 20 and 70 years old and were recruited as participants for the Berlin Aging Study II. Associations were assessed using linear regression analysis. Despite having sufficient power to detect the previously reported effect sizes, we found no evidence for statistically significant associations between the tested CTNNBL1 SNPs and any of the 14 measures of episodic memory. The previously reported effects of genetic polymorphisms in CTNNBL1 on episodic memory performance do not generalize to the broad range of tasks assessed in our cohort. If not altogether spurious, the effects may be limited to a very narrow phenotypic domain (that is, verbal delayed free recall between 5 and 30 min). More studies are needed to further clarify the role of CTNNBL1 in human memory.

  8. Sleep for preserving and transforming episodic memory.

    PubMed

    Inostroza, Marion; Born, Jan

    2013-07-08

    Sleep is known to support memory consolidation. Here we review evidence for an active system consolidation occurring during sleep. At the beginning of this process is sleep's ability to preserve episodic experiences preferentially encoded in hippocampal networks. Repeated neuronal reactivation of these representations during slow-wave sleep transforms episodic representations into long-term memories, redistributes them toward extrahippocampal networks, and qualitatively changes them to decontextualized schema-like representations. Electroencephalographic (EEG) oscillations regulate the underlying communication: Hippocampal sharp-wave ripples coalescing with thalamic spindles mediate the bottom-up transfer of reactivated memory information to extrahippocampal regions. Neocortical slow oscillations exert a supraordinate top-down control to synchronize hippocampal reactivations of specific memories to their excitable up-phase, thus allowing plastic changes in extrahippocampal regions. We propose that reactivations during sleep are a general mechanism underlying the abstraction of temporally stable invariants from a flow of input that is solely structured in time, thus representing a basic mechanism of memory formation.

  9. Reduced Hippocampal Functional Connectivity During Episodic Memory Retrieval in Autism.

    PubMed

    Cooper, Rose A; Richter, Franziska R; Bays, Paul M; Plaisted-Grant, Kate C; Baron-Cohen, Simon; Simons, Jon S

    2017-02-01

    Increasing recent research has sought to understand the recollection impairments experienced by individuals with autism spectrum disorder (ASD). Here, we tested whether these memory deficits reflect a reduction in the probability of retrieval success or in the precision of memory representations. We also used functional magnetic resonance imaging (fMRI) to study the neural mechanisms underlying memory encoding and retrieval in ASD, focusing particularly on the functional connectivity of core episodic memory networks. Adults with ASD and typical control participants completed a memory task that involved studying visual displays and subsequently using a continuous dial to recreate their appearance. The ASD group exhibited reduced retrieval success, but there was no evidence of a difference in retrieval precision. fMRI data revealed similar patterns of brain activity and functional connectivity during memory encoding in the 2 groups, though encoding-related lateral frontal activity predicted subsequent retrieval success only in the control group. During memory retrieval, the ASD group exhibited attenuated lateral frontal activity and substantially reduced hippocampal connectivity, particularly between hippocampus and regions of the fronto-parietal control network. These findings demonstrate notable differences in brain function during episodic memory retrieval in ASD and highlight the importance of functional connectivity to understanding recollection-related retrieval deficits in this population.

  10. 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

  11. III. NIH TOOLBOX COGNITION BATTERY (CB): MEASURING EPISODIC MEMORY

    PubMed Central

    Bauer, Patricia J.; Dikmen, Sureyya S.; Heaton, Robert K.; Mungas, Dan; Slotkin, Jerry; Beaumont, Jennifer L.

    2014-01-01

    One of the most significant domains of cognition is episodic memory, which allows for rapid acquisition and long-term storage of new information. For purposes of the NIH Toolbox, we devised a new test of episodic memory. The nonverbal NIH Toolbox Picture Sequence Memory Test (TPSMT) requires participants to reproduce the order of an arbitrarily ordered sequence of pictures presented on a computer. To adjust for ability, sequence length varies from 6 to 15 pictures. Multiple trials are administered to increase reliability. Pediatric data from the validation study revealed the TPSMT to be sensitive to age-related changes. The task also has high test– retest reliability and promising construct validity. Steps to further increase the sensitivity of the instrument to individual and age-related variability are described. PMID:23952201

  12. Anterograde Episodic Memory in Korsakoff Syndrome

    PubMed Central

    Fama, Rosemary; Pitel, Anne-Lise; Sullivan, Edith V.

    2016-01-01

    A profound anterograde memory deficit for information, regardless of the nature of the material, is the hallmark of Korsakoff syndrome, an amnesic condition resulting from severe thiamine (vitamin B1) deficiency. Since the late nineteenth century when the Russian physician, S. S. Korsakoff, initially described this syndrome associated with “polyneuropathy,” the observed global amnesia has been a primary focus of neuroscience and neuropsychology. In this review we highlight the historical studies that examined anterograde episodic memory processes in KS, present a timeline and evidence supporting the myriad theories proffered to account for this memory dysfunction, and summarize what is known about the neuroanatomical correlates and neural systems presumed affected in KS. Rigorous study of KS amnesia and associated memory disorders of other etiologies provide evidence for distinct mnemonic component processes and neural networks imperative for normal declarative and nondeclarative memory abilities and for mnemonic processes spared in KS, from whence emerged the appreciation that memory is not a unitary function. Debate continues regarding the qualitative and quantitative differences between KS and other amnesias and what brain regions and neural pathways are necessary and sufficient to produce KS amnesia. PMID:22644546

  13. 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…

  14. 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.

  15. Sex differences in episodic memory: minimal influence of estradiol.

    PubMed

    Yonker, Julie E; Eriksson, Elias; Nilsson, Lars Göran; Herlitz, Agneta

    2003-07-01

    Sex differences exist for several cognitive tasks and estrogen has been suggested to influence these differences. Eighteen men and 18 women were matched on age and estradiol level. Potential sex differences were assessed in episodic memory, semantic memory, verbal fluency, problem solving, and visuospatial ability. Significant sex differences, favoring women, were found for tasks assessing episodic memory. Correlations between estradiol level and cognitive performance were significant for face recognition in females. Since sex differences remained in verbal episodic memory tasks and face recognition despite matched levels of estradiol, circulating estradiol does not appear to be of paramount consequence for observed sex differences in episodic memory.

  16. 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…

  17. 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…

  18. False memories in highly superior autobiographical memory individuals

    PubMed Central

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

    2013-01-01

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

  19. False memories in highly superior autobiographical memory individuals.

    PubMed

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

    2013-12-24

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

  20. 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.

  1. Interaction between categorical knowledge and episodic memory across domains

    PubMed Central

    Hemmer, Pernille; Persaud, Kimele

    2014-01-01

    Categorical knowledge and episodic memory have traditionally been viewed as separate lines of inquiry. Here, we present a perspective on the interrelatedness of categorical knowledge and reconstruction from memory. We address three underlying questions: what knowledge do people bring to the task of remembering? How do people integrate that knowledge with episodic memory? Is this the optimal way for the memory system to work? In the review of five studies spanning four category domains (discrete, continuous, temporal, and linguistic), we evaluate the relative contribution and the structure of influence of categorical knowledge on long-term episodic memory. These studies suggest a robustness of peoples’ knowledge of the statistical regularities of the environment, and provide converging evidence of the quality and influence of category knowledge on reconstructive memory. Lastly, we argue that combining categorical knowledge and episodic memory is an efficient strategy of the memory system. PMID:24966848

  2. Episodic and Semantic Memory Contribute to Familiar and Novel Episodic Future Thinking

    PubMed Central

    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. PMID:27891106

  3. 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.

  4. Genetics of human episodic memory: dealing with complexity.

    PubMed

    Papassotiropoulos, Andreas; de Quervain, Dominique J-F

    2011-09-01

    Episodic memory is a polygenic behavioral trait with substantial heritability estimates. Despite its complexity, recent empirical evidence supports the notion that behavioral genetic studies of episodic memory might successfully identify trait-associated molecules and pathways. The development of high-throughput genotyping methods, of elaborated statistical analyses and of phenotypic assessment methods at the neural systems level will facilitate the reliable identification of novel memory-related genes. Importantly, a necessary crosstalk between behavioral genetic studies and investigation of causality by molecular genetic studies will ultimately pave the way towards the identification of biologically important, and hopefully druggable, genes and molecular pathways related to human episodic memory.

  5. Episodic and semantic memory in bilingual and monolingual children.

    PubMed

    Kormi-Nouri, Reza; Moniri, Sadegheh; Nilsson, Lars-Göran

    2003-02-01

    Although bilinguality has been reported to confer advantages upon children with respect to various cognitive abilities, much less is known about the relation between memory and bilinguality. In this study, 60 (30 girls and 30 boys) bilingual and 60 (30 girls and 30 boys) monolingual children in three age groups (mean ages 8.5, 10.5 and 12.5 years) were compared on episodic memory and semantic memory tasks. Episodic memory was assessed using subject-performed tasks (with real or imaginary objects) and verbal tasks, with retrieval by both free recall and cued recall. Semantic memory was assessed by word fluency tests. Positive effects of bilingualism were found on both episodic memory and semantic memory at all age levels. These findings suggest that bilingual children integrate and/or organize the information of two languages, and so bilingualism creates advantages in terms of cognitive abilities (including memory). Some sex differences were also found in episodic memory but not in semantic memory. This episodic memory difference was found with younger children.

  6. Atypical Neurophysiology Underlying Episodic and Semantic Memory in Adults with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Massand, Esha; Bowler, Dermot M.

    2015-01-01

    Individuals with autism spectrum disorder (ASD) show atypicalities in episodic memory (Boucher et al. in Psychological Bulletin, 138 (3), 458-496, 2012). We asked participants to recall the colours of a set of studied line drawings (episodic judgement), or to recognize line drawings alone (semantic judgement). Cycowicz et al. ("Journal of…

  7. Validation of a rodent model of episodic memory

    PubMed Central

    Zhou, Wenyi

    2011-01-01

    Episodic memory consists of representations of specific episodes that happened in the past. Modeling episodic memory in animals requires careful examination of alternative explanations of performance. Putative evidence of episodic-like memory may be based on encoding failure or expectations derived from well-learned semantic rules. In Experiment 1, rats were tested in a radial maze with study and test phases separated by a retention interval. The replenishment of chocolate (at its study-phase location) depended on two factors: time of day (morning vs. afternoon) and the presence or absence of chocolate pellets at the start of the test phase. Because replenishment could not be decoded until the test phase, rats were required to encode the study episode. Success in this task rules out encoding failure. In Experiment 2, two identical mazes in different rooms were used. Chocolate replenishment was trained in one room, and then they were asked to report about a recent event in a different room, where they had no expectation that the memory assessment would occur. Rats successfully answered the unexpected question, ruling out use of expectations derived from well-learned semantic rules. Our behavioral methods for modeling episodic memory may have broad application for assessments of genetic, neuroanatomical, neurochemical, and neurophysiological bases of both episodic memory and memory disorders such as those that occur in Alzheimer’s disease. PMID:21165663

  8. 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

  9. 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.

  10. 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

  11. 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.

  12. Vection Modulates Emotional Valence of Autobiographical Episodic Memories

    ERIC Educational Resources Information Center

    Seno, Takeharu; Kawabe, Takahiro; Ito, Hiroyuki; Sunaga, Shoji

    2013-01-01

    We examined whether illusory self-motion perception ("vection") induced by viewing upward and downward grating motion stimuli can alter the emotional valence of recollected autobiographical episodic memories. We found that participants recollected positive episodes more often while perceiving upward vection. However, when we tested a small moving…

  13. KIBRA gene polymorphism has no association with verbal or visual episodic memory performance

    PubMed Central

    Franks, Katherine H.; Summers, Mathew J.; Vickers, James C.

    2014-01-01

    Inter-individual variability in memory performance has been suggested to result, in part, from genetic differences in the coding of proteins involved in long-term potentiation (LTP). The present study examined the effect of a single-nucleotide polymorphism (SNP) in the KIBRA gene (rs17070145) on episodic memory performance, using multiple measures of verbal and visual episodic memory. A total of 256 female and 130 male healthy, older adults (mean age = 60.86 years) were recruited from the Tasmanian Healthy Brain Project (THBP), undergoing both neuropsychological and genetic testing. The current study showed no significant effect of the KIBRA polymorphism on performance on the Rey Auditory Verbal Learning Task, Logical Memory test, Paired Associates Learning test or Rey Complex Figure Task. The results suggest there is little to no functional significance of KIBRA genotype on episodic memory performance, regardless of modality. PMID:25339899

  14. Episodic memory in normal aging and Alzheimer disease: Insights from imaging and behavioral studies.

    PubMed

    Tromp, D; Dufour, A; Lithfous, S; Pebayle, T; Després, O

    2015-11-01

    Age-related cognitive changes often include difficulties in retrieving memories, particularly those that rely on personal experiences within their temporal and spatial contexts (i.e., episodic memories). This decline may vary depending on the studied phase (i.e., encoding, storage or retrieval), according to inter-individual differences, and whether we are talking about normal or pathological (e.g., Alzheimer disease; AD) aging. Such cognitive changes are associated with different structural and functional alterations in the human neural network that underpins episodic memory. The prefrontal cortex is the first structure to be affected by age, followed by the medial temporal lobe (MTL), the parietal cortex and the cerebellum. In AD, however, the modifications occur mainly in the MTL (hippocampus and adjacent structures) before spreading to the neocortex. In this review, we will present results that attempt to characterize normal and pathological cognitive aging at multiple levels by integrating structural, behavioral, inter-individual and neuroimaging measures of episodic memory.

  15. 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.

  16. Higher body mass index is associated with episodic memory deficits in young adults

    PubMed Central

    Cheke, Lucy G.; Simons, Jon S.; Clayton, Nicola S.

    2016-01-01

    Obesity has become an international health crisis. There is accumulating evidence that excess bodyweight is associated with changes to the structure and function of the brain and with a number of cognitive deficits. In particular, research suggests that obesity is associated with hippocampal and frontal lobe dysfunction, which would be predicted to impact memory. However, evidence for such memory impairment is currently limited. We hypothesised that higher body mass index (BMI) would be associated with reduced performance on a test of episodic memory that assesses not only content, but also context and feature integration. A total of 50 participants aged 18–35 years, with BMIs ranging from 18 to 51, were tested on a novel what–where–when style episodic memory test: the “Treasure-Hunt Task”. This test requires recollection of object, location, and temporal order information within the same paradigm, as well as testing the ability to integrate these features into a single event recollection. Higher BMI was associated with significantly lower performance on the what–where–when (WWW) memory task and all individual elements: object identification, location memory, and temporal order memory. After controlling for age, sex, and years in education, the effect of BMI on the individual what, where, and when tasks remained, while the WWW dropped below significance. This finding of episodic memory deficits in obesity is of concern given the emerging evidence for a role for episodic cognition in appetite regulation. PMID:26447832

  17. 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…

  18. CPEB3 is associated with human episodic memory.

    PubMed

    Vogler, Christian; Spalek, Klara; Aerni, Amanda; Demougin, Philippe; Müller, Ariane; Huynh, Kim-Dung; Papassotiropoulos, Andreas; de Quervain, Dominique J-F

    2009-01-01

    Cytoplasmic polyadenylation element-binding (CPEB) proteins are crucial for synaptic plasticity and memory in model organisms. A highly conserved, mammalian-specific short intronic sequence within CPEB3 has been identified as a ribozyme with self-cleavage properties. In humans, the ribozyme sequence is polymorphic and harbors a single nucleotide polymorphism that influences cleavage activity of the ribozyme. Here we show that this variation is related to performance in an episodic memory task and that the effect of the variation depends on the emotional valence of the presented material. Our data suggest a role for human CPEB3 in human episodic memory.

  19. A Reduction in Delay Discounting by Using Episodic Future Imagination and the Association with Episodic Memory Capacity

    PubMed Central

    Hu, Xiaochen; Kleinschmidt, Helena; Martin, Jason A.; Han, Ying; Thelen, Manuela; Meiberth, Dix; Jessen, Frank; Weber, Bernd

    2017-01-01

    Delay discounting (DD) refers to the phenomenon that individuals discount future consequences. Previous studies showed that future imagination reduces DD, which was mediated by functional connectivity between medial prefrontal valuation areas and a key region for episodic memory (hippocampus). Future imagination involves an initial period of construction and a later period of elaboration, with the more elaborative latter period recruiting more cortical regions. This study examined whether elaborative future imagination modulated DD, and if so, what are the underlying neural substrates. It was assumed that cortical areas contribute to the modulation effect during the later period of imagination. Since future imagination is supported by episodic memory capacity, we additionally hypothesize that the neural network underlying the modulation effect is related to individual episodic memory capacity. Twenty-two subjects received an extensive interview on personal future events, followed by an fMRI DD experiment with and without the need to perform elaborative future imagination simultaneously. Subjects' episodic memory capacity was also assessed. Behavioral results replicate previous findings of a reduced discount rate in the DD plus imagination condition compared to the DD only condition. The behavioral effect positively correlated with: (i) subjective value signal changes in midline brain structures during the initial imagination period; and (ii) signal changes in left prefrontoparietal areas during the later imagination period. Generalized psychophysiological interaction (gPPI) analyses reveal positive correlations between the behavioral effect and functional connectivity among the following areas: right anterior cingulate cortex (ACC) and left hippocampus; left inferior parietal cortex (IPC) and left hippocampus; and left IPC and bilateral occipital cortices. These changes in functional connectivity are also associated with episodic memory capacity. A hierarchical

  20. Preschool children's proto-episodic memory assessed by deferred imitation.

    PubMed

    Burns, Patrick; Russell, Charlotte; Russell, James

    2015-01-01

    In two experiments, both employing deferred imitation, we studied the developmental origins of episodic memory in two- to three-year-old children by adopting a "minimalist" view of episodic memory based on its What-When-Where ("WWW": spatiotemporal plus semantic) content. We argued that the temporal element within spatiotemporal should be the order/simultaneity of the event elements, but that it is not clear whether the spatial content should be egocentric or allocentric. We also argued that episodic recollection should be configural (tending towards all-or-nothing recall of the WWW elements). Our first deferred imitation experiment, using a two-dimensional (2D) display, produced superior-to-chance performance after 2.5 years but no evidence of configural memory. Moreover, performance did not differ from that on a What-What-What control task. Our second deferred imitation study required the children to reproduce actions on an object in a room, thereby affording layout-based spatial cues. In this case, not only was there superior-to-chance performance after 2.5 years but memory was also configural at both ages. We discuss the importance of allocentric spatial cues in episodic recall in early proto-episodic memory and reflect on the possible role of hippocampal development in this process.

  1. 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

  2. Episodic future thinking as a predictor of children's prospective memory.

    PubMed

    Nigro, Giovanna; Brandimonte, Maria A; Cicogna, PierCarla; Cosenza, Marina

    2014-11-01

    The primary goal of this study was to investigate the relationship among retrospective memory, episodic future thinking, and event-based prospective memory performance in preschool, first-grade, and second-grade children. A total of 160 children took part in the experiment. The study included participants from four age groups: 4-year-olds, 5-year-olds, 6-year-olds, and 7-year-olds. Participants were administered a recognition memory task, a task to test the ability to pre-experience future events, and an event-based prospective memory task. Data were submitted to correlational analyses, analyses of variance (ANOVAs), and logistic regression analyses. Results showed that, overall, all of these abilities improve with age and are significantly correlated with one another. However, when partialling out age and retrospective memory, episodic future thinking and prospective memory performance remained correlated. Logistic regression further showed that age and episodic future thinking abilities were significant predictors of prospective memory performance independent of retrospective memory abilities.

  3. 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

  4. 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.

  5. Aging Memories: Differential Decay of Episodic Memory Components

    ERIC Educational Resources Information Center

    Talamini, Lucia M.; Gorree, Eva

    2012-01-01

    Some memories about events can persist for decades, even a lifetime. However, recent memories incorporate rich sensory information, including knowledge on the spatial and temporal ordering of event features, while old memories typically lack this "filmic" quality. We suggest that this apparent change in the nature of memories may reflect a…

  6. Recognition of Famous Names Predicts Episodic Memory Decline in Cognitively Intact Elders

    PubMed Central

    Seidenberg, Michael; Kay, Christina; Woodard, John L.; Nielson, Kristy A.; Smith, J. Carson; Kandah, Cassandra; Guidotti Breting, Leslie M.; Novitski, Julia; Lancaster, Melissa; Matthews, Monica; Hantke, Nathan; Butts, Alissa; Rao, Stephen M.

    2013-01-01

    Objective: Semantic memory impairment is common in both Mild Cognitive Impairment (MCI) and early Alzheimer’s disease (AD), and the ability to recognize familiar people is particularly vulnerable. A time-limited temporal gradient (TG) in which well known people from decades earlier are better recalled than those learned recently is also reported in both AD and MCI. In this study, we hypothesized that the TG pattern on a famous name recognition task (FNRT) administered to cognitively intact elders would predict future episodic memory decline, and would also show a significant correlation with hippocampal volume. Methods: 78 healthy elders (ages 65-90) with normal cognition and episodic memory at baseline were administered a FNRT. Follow-up episodic memory testing 18 months later produced two groups: Declining (≥ 1 SD reduction in episodic memory) and Stable (< 1 SD). Results: The Declining group (N=27) recognized fewer recent famous names than the Stable group (N=51), while recognition for remote names was comparable. Baseline MRI volumes for both the left and right hippocampus was significantly smaller in the Declining group than the Stable group. Smaller baseline hippocampal volume was also significantly correlated with poorer performance for recent, but not remote famous names. Logistic regression analyses indicated that baseline TG performance was a significant predictor of group status (Declining versus Stable) independent of chronological age and APOE ε4 inheritance. Conclusions: Famous name recognition may serve as an early pre-clinical cognitive marker of episodic memory decline in older individuals. PMID:23688215

  7. A bird-brain view of episodic memory.

    PubMed

    Rattenborg, N C; Martinez-Gonzalez, D

    2011-09-12

    In humans, the hippocampus plays a critical role in the formation of episodic memories. Although non-human animals are unable to report whether they also re-experience past events, at least some birds and mammals exhibit 'episodic-like' memory characterized by an ability to recall what happened where and when. In mammals, the hippocampus interacts closely with virtually the entire neocortex to form episodic-like memories. The hippocampus receives highly processed information from high-order association areas, and thereby the rest of the neocortex. Distinct neurophysiological hippocampal rhythms (theta and sharp-wave ripples) coordinate activity between the hippocampus and high-order association areas during the encoding and retrieval of information contributing to episodic-like memories. Although recent studies have demonstrated that food hoarding birds are able to remember what food they hid where and when, neuroanatomical and neurophysiological studies suggest that there may be a fundamental difference between episodic-like memory in birds and mammals. In contrast to the mammalian hippocampus, the avian hippocampus only receives visual and olfactory input; most high-order association areas in the avian brain involved in performing functions similar to those performed by neocortical association areas do not project to the hippocampus or structures providing it with direct input. Consistent with this neuroanatomical difference, mammalian-like rhythms involved in communicating between the hippocampus and neocortical high-order association areas have not been found in birds. Collectively, this suggests that information contributing to episodic-like memory is more limited and processed in a different manner in birds when compared to mammals.

  8. Cortical thickness mediates the effect of β-amyloid on episodic memory

    PubMed Central

    Reed, Bruce R.; Wirth, Miranka; Haase, Claudia M.; Madison, Cindee M.; Ayakta, Nagehan; Mack, Wendy; Mungas, Dan; Chui, Helena C.; DeCarli, Charles; Weiner, Michael W.; Jagust, William J.

    2014-01-01

    Objective: To investigate the associations among β-amyloid (Aβ), cortical thickness, and episodic memory in a cohort of cognitively normal to mildly impaired individuals at increased risk of vascular disease. Methods: In 67 subjects specifically recruited to span a continuum of cognitive function and vascular risk, we measured brain Aβ deposition using [11C] Pittsburgh compound B–PET imaging and cortical thickness using MRI. Episodic memory was tested using a standardized composite score of verbal memory, and vascular risk was quantified using the Framingham Coronary Risk Profile index. Results: Increased Aβ was associated with cortical thinning, notably in frontoparietal regions. This relationship was strongest in persons with high Aβ deposition. Increased Aβ was also associated with lower episodic memory performance. Cortical thickness was found to mediate the relationship between Aβ and memory performance. While age had a marginal effect on these associations, the relationship between Aβ and cortical thickness was eliminated after controlling for vascular risk except when examined in only Pittsburgh compound B–positive subjects, in whom Aβ remained associated with thinner cortex in precuneus and occipital lobe. In addition, only the precuneus was found to mediate the relationship between Aβ and memory after controlling for vascular risk. Conclusion: These results suggest strong links among Aβ, cortical thickness, and memory. They highlight that, in individuals without dementia, vascular risk also contributes to cortical thickness and influences the relationships among Aβ, cortical thickness, and memory. PMID:24489134

  9. The representation of social interaction in episodic memory: a functional MRI study.

    PubMed

    Mano, Yoko; Sugiura, Motoaki; Tsukiura, Takashi; Chiao, Joan Y; Yomogida, Yukihito; Jeong, Hyeonjeong; Sekiguchi, Atsushi; Kawashima, Ryuta

    2011-08-01

    The representation of social interaction in episodic memory is a critical factor for the successful navigation of social relationships. In general, it is important to separate episodic memory during social interaction from episodic memory during the self-generation of action events. Different cortical representations have been associated with social interaction vs. self-generated episodic memory. Here we clarified the cortical representation of the effect of context (social vs. solitary) on episodic memory by comparing it with the generation effect (self vs. other) on episodic memory. Each participant learned words while engaged in a sentence generation and a reading task, and subsequently each participant was scanned with functional magnetic resonance imaging (fMRI) while they performed a recognition task using the words that had been learned. The experiment was comprised of four conditions and we looked at two situations that involved a social context and non-social (solitary) context task. In the learning session before entering the MRI, two participants collaborated in a social context either generating (social-contextual self-generation condition: SS) or reading (social-contextual other-generation condition: SO) a sequence of sentences alternately to construct a meaningful story narrative. In the non-social context, the participants generated (non-social-contextual self-generation condition: NS) or read (non-social-contextual other-generation condition: NO) a sequence of sentences individually. The stimuli for the recognition session consisted of learned words and novel words. Activation for social context retrieval was identified in the right medial prefrontal cortex (mPFC), and activation for self-generated retrieval was identified in the left mPFC and the left middle cingulate cortex. These results indicate that dissociable regions within the medial prefrontal cortices contribute to the processes involved in the representation of social interaction

  10. Autobiographical and episodic memory deficits in mild traumatic brain injury.

    PubMed

    Wammes, Jeffrey D; Good, Tyler J; Fernandes, Myra A

    2017-02-01

    Those who have suffered a concussion, otherwise known as a mild traumatic brain injury (mTBI), often complain of lingering memory problems. However, there is little evidence in the behavioral literature reliably demonstrating memory deficits. Thus, in the present study, cognitive profiles including measures of general executive functioning and processing speed, as well as episodic and semantic memory were collected in younger and older adult participants with or without a remote (>1year prior to testing) mTBI. We first investigated whether there were observable episodic and autobiographical memory impairments associated with mTBI within an otherwise healthy young group. Next, because previous work had demonstrated some overlap in patterns of behavioral impairment in normally aging adults and younger adults with a history of mTBI (e.g. Ozen, Fernandes, Clark, & Roy, 2015), we sought to determine whether these groups displayed similar cognitive profiles. Lastly, we conducted an exploratory analysis to test whether having suffered an mTBI might exacerbate age-related cognitive decline. Results showed the expected age-related decline in episodic memory performance, coupled with a relative preservation of semantic memory in older adults. Importantly, this pattern was also present in younger adults with a history of remote mTBI. No differences were observed across older adult groups based on mTBI status. Logistic regression analyses, using each measure in our battery as a predictor, successfully classified mTBI status in younger participants with a high degree of specificity (79.5%). These results indicate that those who have had an mTBI demonstrate a distinct cognitive signature, characterized by impairment in episodic and autobiographical memory, coupled with a relative preservation of semantic memory.

  11. Episodic Memory and Appetite Regulation in Humans

    PubMed Central

    Brunstrom, Jeffrey M.; Burn, Jeremy F.; Sell, Nicola R.; Collingwood, Jane M.; Rogers, Peter J.; Wilkinson, Laura L.; Hinton, Elanor C.; Maynard, Olivia M.; Ferriday, Danielle

    2012-01-01

    Psychological and neurobiological evidence implicates hippocampal-dependent memory processes in the control of hunger and food intake. In humans, these have been revealed in the hyperphagia that is associated with amnesia. However, it remains unclear whether ‘memory for recent eating’ plays a significant role in neurologically intact humans. In this study we isolated the extent to which memory for a recently consumed meal influences hunger and fullness over a three-hour period. Before lunch, half of our volunteers were shown 300 ml of soup and half were shown 500 ml. Orthogonal to this, half consumed 300 ml and half consumed 500 ml. This process yielded four separate groups (25 volunteers in each). Independent manipulation of the ‘actual’ and ‘perceived’ soup portion was achieved using a computer-controlled peristaltic pump. This was designed to either refill or draw soup from a soup bowl in a covert manner. Immediately after lunch, self-reported hunger was influenced by the actual and not the perceived amount of soup consumed. However, two and three hours after meal termination this pattern was reversed - hunger was predicted by the perceived amount and not the actual amount. Participants who thought they had consumed the larger 500-ml portion reported significantly less hunger. This was also associated with an increase in the ‘expected satiation’ of the soup 24-hours later. For the first time, this manipulation exposes the independent and important contribution of memory processes to satiety. Opportunities exist to capitalise on this finding to reduce energy intake in humans. PMID:23227200

  12. Episodic-Like Memory in a Gorilla: A Review and New Findings

    ERIC Educational Resources Information Center

    Schwartz, B.L.; Hoffman, M.L.; Evans, S.

    2005-01-01

    The current paper examines if gorillas (Gorilla gorilla gorilla) possess an episodic memory system. Episodic memory, in humans, is a neurocognitive system that stores information about the personal past. Unique to episodic memory is its palinscopic or past-focused orientation; most memory systems serve to provide the organism with up to date…

  13. Sex differences favoring women in verbal but not in visuospatial episodic memory.

    PubMed

    Lewin, C; Wolgers, G; Herlitz, A

    2001-04-01

    Sex differences favoring women have been found in a number of studies of episodic memory. This study examined sex differences in verbal, nonverbal, and visuospatial episodic memory tasks. Results showed that although women performed at a higher level on a composite verbal and nonverbal episodic memory score, men performed at a higher level on a composite score of episodic memory tasks requiring visuospatial processing. Thus, men can use their superior visuospatial abilities to excel in highly visuospatial episodic memory tasks, whereas women seem to excel in episodic memory tasks in which a verbalization of the material is possible.

  14. The Nature of Episodic Memory Deficits in MCI with and without Vascular Burden

    ERIC Educational Resources Information Center

    Villeneuve, Sylvia; Massoud, Fadi; Bocti, Christian; Gauthier, Serge; Belleville, Sylvie

    2011-01-01

    This study measured episodic memory deficits in individuals with mild cognitive impairment (MCI) as a function of their vascular burden. Vascular burden was determined clinically by computing the number of vascular risk factors and diseases and neuroradiologically by assessing the presence and severity of white matter lesions (WML). Strategic…

  15. The interaction of working memory performance and episodic memory formation in patients with Korsakoff's amnesia.

    PubMed

    van Geldorp, Bonnie; Bergmann, Heiko C; Robertson, Johanna; Wester, Arie J; Kessels, Roy P C

    2012-01-18

    Both neuroimaging work and studies investigating amnesic patients have shown involvement of the medial temporal lobe during working memory tasks, especially when multiple items or features have to be associated. However, so far no study has examined the relationship between working memory and subsequent episodic memory in patients using similar tasks. In this study, we compared patients with amnesia due to Korsakoff's syndrome (n=19) with healthy controls (n=18) on an associative working memory task followed by an unexpected subsequent episodic memory task. The computerized working memory task required participants to maintain two pairs of faces and houses for either short (3s) or long (6s) delays. Approximately 5 minutes after completion of the working memory task, an unexpected subsequent recognition task with a two-alternative forced choice paradigm was administered. By directly comparing working memory and subsequent episodic memory, we were able to examine long-term encoding processes that may take place after longer delays. As expected, patients performed at chance level on the episodic memory task. Interestingly, patients also showed significantly impaired working memory performance (p<.01), even at short delays. Longer delays did not result in better subsequent memory, indicating that they do not facilitate long-term encoding processes. Our results are discussed in relation to Baddeley's working memory model as the episodic buffer is assumed to be a short-term store for maintaining bound representations. In light of these results, the long-standing view that working memory and long-term memory are strictly dissociated may need to be revisited.

  16. Emotional intensity in episodic autobiographical memory and counterfactual thinking.

    PubMed

    Stanley, Matthew L; Parikh, Natasha; Stewart, Gregory W; De Brigard, Felipe

    2017-02-01

    Episodic counterfactual thoughts-imagined alternative ways in which personal past events might have occurred-are frequently accompanied by intense emotions. Here, participants recollected positive and negative autobiographical memories and then generated better and worse episodic counterfactual events from those memories. Our results suggest that the projected emotional intensity during the simulated remembered/imagined event is significantly higher than but typically positively related to the emotional intensity while remembering/imagining the event. Furthermore, repeatedly simulating counterfactual events heightened the emotional intensity felt while simulating the counterfactual event. Finally, for both the emotional intensity accompanying the experience of remembering/imagining and the projected emotional intensity during the simulated remembered/imagined event, the emotional intensity of negative memories was greater than the emotional intensity of upward counterfactuals generated from them but lower than the emotional intensity of downward counterfactuals generated from them. These findings are discussed in relation to clinical work and functional theories of counterfactual thinking.

  17. Preserved emotional memory modulation in first episode psychosis.

    PubMed

    Dieleman, Sieds; van der Veen, Frederik; van Beveren, Nico; Röder, Christian

    2015-03-30

    Although patients with schizophrenia have severe memory impairments and emotional deficits, studies investigating emotional memory modulation (EMM) in schizophrenia show contradictory results, possibly due to methodological differences and small group size. We investigated whether impaired EMM is already present in First Episode Psychosis (FEP) and whether impairments in EMM are task or stimulus dependent. Forty-five FEP and thirty-seven Healthy Control (HC) male participants matched for age performed visual and verbal short-term (immediate recall) and long-term (after 24h recognition) memory tasks with neutral, negative and positive stimuli. On all tasks overall memory performance for FEP was significantly below that of HC. Although EMM varied by task and type of stimulus, none of the tasks showed a difference in EMM between FEP and HC. There were no differences between FEP and HC in the way emotion modulates different memory domains. This could mean that EMM is spared in the early course of schizophrenia.

  18. Episodic Memory Retrieval Benefits from a Less Modular Brain Network Organization.

    PubMed

    Westphal, Andrew J; Wang, Siliang; Rissman, Jesse

    2017-03-29

    Most complex cognitive tasks require the coordinated interplay of multiple brain networks, but the act of retrieving an episodic memory may place especially heavy demands for communication between the frontoparietal control network (FPCN) and the default mode network (DMN), two networks that do not strongly interact with one another in many task contexts. We applied graph theoretical analysis to task-related fMRI functional connectivity data from 20 human participants and found that global brain modularity-a measure of network segregation-is markedly reduced during episodic memory retrieval relative to closely matched analogical reasoning and visuospatial perception tasks. Individual differences in modularity were correlated with memory task performance, such that lower modularity levels were associated with a lower false alarm rate. Moreover, the FPCN and DMN showed significantly elevated coupling with each other during the memory task, which correlated with the global reduction in brain modularity. Both networks also strengthened their functional connectivity with the hippocampus during the memory task. Together, these results provide a novel demonstration that reduced modularity is conducive to effective episodic retrieval, which requires close collaboration between goal-directed control processes supported by the FPCN and internally oriented self-referential processing supported by the DMN.SIGNIFICANCE STATEMENT Modularity, an index of the degree to which nodes of a complex system are organized into discrete communities, has emerged as an important construct in the characterization of brain connectivity dynamics. We provide novel evidence that the modularity of the human brain is reduced when individuals engage in episodic memory retrieval, relative to other cognitive tasks, and that this state of lower modularity is associated with improved memory performance. We propose a neural systems mechanism for this finding where the nodes of the frontoparietal control

  19. 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.

  20. Early remodeling of the neocortex upon episodic memory encoding.

    PubMed

    Bero, Adam W; Meng, Jia; Cho, Sukhee; Shen, Abra H; Canter, Rebecca G; Ericsson, Maria; Tsai, Li-Huei

    2014-08-12

    Understanding the mechanisms by which long-term memories are formed and stored in the brain represents a central aim of neuroscience. Prevailing theory suggests that long-term memory encoding involves early plasticity within hippocampal circuits, whereas reorganization of the neocortex is thought to occur weeks to months later to subserve remote memory storage. Here we report that long-term memory encoding can elicit early transcriptional, structural, and functional remodeling of the neocortex. Parallel studies using genome-wide RNA sequencing, ultrastructural imaging, and whole-cell recording in wild-type mice suggest that contextual fear conditioning initiates a transcriptional program in the medial prefrontal cortex (mPFC) that is accompanied by rapid expansion of the synaptic active zone and postsynaptic density, enhanced dendritic spine plasticity, and increased synaptic efficacy. To address the real-time contribution of the mPFC to long-term memory encoding, we performed temporally precise optogenetic inhibition of excitatory mPFC neurons during contextual fear conditioning. Using this approach, we found that real-time inhibition of the mPFC inhibited activation of the entorhinal-hippocampal circuit and impaired the formation of long-term associative memory. These findings suggest that encoding of long-term episodic memory is associated with early remodeling of neocortical circuits, identify the prefrontal cortex as a critical regulator of encoding-induced hippocampal activation and long-term memory formation, and have important implications for understanding memory processing in healthy and diseased brain states.

  1. Reactivation of Reward-Related Patterns from Single Past Episodes Supports Memory-Based Decision Making.

    PubMed

    Wimmer, G Elliott; Büchel, Christian

    2016-03-09

    Rewarding experiences exert a strong influence on later decision making. While decades of neuroscience research have shown how reinforcement gradually shapes preferences, decisions are often influenced by single past experiences. Surprisingly, relatively little is known about the influence of single learning episodes. Although recent work has proposed a role for episodes in decision making, it is largely unknown whether and how episodic experiences contribute to value-based decision making and how the values of single episodes are represented in the brain. In multiple behavioral experiments and an fMRI experiment, we tested whether and how rewarding episodes could support later decision making. Participants experienced episodes of high reward or low reward in conjunction with incidental, trial-unique neutral pictures. In a surprise test phase, we found that participants could indeed remember the associated level of reward, as evidenced by accurate source memory for value and preferences to re-engage with rewarded objects. Further, in a separate experiment, we found that high-reward objects shown as primes before a gambling task increased financial risk taking. Neurally, re-exposure to objects in the test phase led to significant reactivation of reward-related patterns. Importantly, individual variability in the strength of reactivation predicted value memory performance. Our results provide a novel demonstration that affect-related neural patterns are reactivated during later experience. Reactivation of value information represents a mechanism by which memory can guide decision making.

  2. 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

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

    2013-11-01

    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.

  3. No association between CTNNBL1 and episodic memory performance

    PubMed Central

    Liu, T; Li, S-C; Papenberg, G; Schröder, J; Roehr, J T; Nietfeld, W; Lindenberger, U; Bertram, L

    2014-01-01

    Polymorphisms in the gene encoding catenin-β-like 1 (CTNNBL1) were recently reported to be associated with verbal episodic memory performance—in particular, delayed verbal free recall assessed between 5 and 30 min after encoding—in a genome-wide association study on healthy young adults. To further examine the genetic effects of CTNNBL1, we tested for association between 455 single-nucleotide polymorphisms (SNPs) in or near CTNNBL1 and 14 measures of episodic memory performance from three different tasks in 1743 individuals. Probands were part of a population-based study of mentally healthy adult men and women, who were between 20 and 70 years old and were recruited as participants for the Berlin Aging Study II. Associations were assessed using linear regression analysis. Despite having sufficient power to detect the previously reported effect sizes, we found no evidence for statistically significant associations between the tested CTNNBL1 SNPs and any of the 14 measures of episodic memory. The previously reported effects of genetic polymorphisms in CTNNBL1 on episodic memory performance do not generalize to the broad range of tasks assessed in our cohort. If not altogether spurious, the effects may be limited to a very narrow phenotypic domain (that is, verbal delayed free recall between 5 and 30 min). More studies are needed to further clarify the role of CTNNBL1 in human memory. PMID:25268258

  4. 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…

  5. Sleep-Dependent Facilitation of Episodic Memory Details

    PubMed Central

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

    2011-01-01

    While a role for sleep in declarative memory processing is established, the qualitative nature of this consolidation benefit, and the physiological mechanisms mediating it, remain debated. Here, we investigate the impact of sleep physiology on characteristics of episodic memory using an item- (memory elements) and context- (contextual details associated with those elements) learning paradigm; the latter being especially dependent on the hippocampus. Following back-to-back encoding of two word lists, each associated with a different context, participants were assigned to either a Nap-group, who obtained a 120-min nap, or a No Nap-group. Six hours post-encoding, participants performed a recognition test involving item-memory and context-memory judgments. In contrast to item-memory, which demonstrated no between-group differences, a significant benefit in context-memory developed in the Nap-group, the extent of which correlated both with the amount of stage-2 NREM sleep and frontal fast sleep-spindles. Furthermore, a difference was observed on the basis of word-list order, with the sleep benefit and associated physiological correlations being selective for the second word-list, learned last (most proximal to sleep). These findings suggest that sleep may preferentially benefit contextual (hippocampal-dependent) aspects of memory, supported by sleep-spindle oscillations, and that the temporal order of initial learning differentially determines subsequent offline consolidation. PMID:22114672

  6. Brain computer interface to enhance episodic memory in human participants

    PubMed Central

    Burke, John F.; Merkow, Maxwell B.; Jacobs, Joshua; Kahana, Michael J.

    2015-01-01

    Recent research has revealed that neural oscillations in the theta (4–8 Hz) and alpha (9–14 Hz) bands are predictive of future success in memory encoding. Because these signals occur before the presentation of an upcoming stimulus, they are considered stimulus-independent in that they correlate with enhanced memory encoding independent of the item being encoded. Thus, such stimulus-independent activity has important implications for the neural mechanisms underlying episodic memory as well as the development of cognitive neural prosthetics. Here, we developed a brain computer interface (BCI) to test the ability of such pre-stimulus activity to modulate subsequent memory encoding. We recorded intracranial electroencephalography (iEEG) in neurosurgical patients as they performed a free recall memory task, and detected iEEG theta and alpha oscillations that correlated with optimal memory encoding. We then used these detected oscillatory changes to trigger the presentation of items in the free recall task. We found that item presentation contingent upon the presence of pre-stimulus theta and alpha oscillations modulated memory performance in more sessions than expected by chance. Our results suggest that an electrophysiological signal may be causally linked to a specific behavioral condition, and contingent stimulus presentation has the potential to modulate human memory encoding. PMID:25653605

  7. Dopamine and Consolidation of Episodic Memory: Timing is Everything.

    PubMed

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

    2015-10-01

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

  8. Dopamine and Consolidation of Episodic Memory: Timing Is Everything

    PubMed Central

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

    2016-01-01

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

  9. Protective effect of APOE epsilon 2 on intrinsic functional connectivity of the entorhinal cortex is associated with better episodic memory in elderly individuals with risk factors for Alzheimer's disease

    PubMed Central

    Chen, Jiu; Shu, Hao; Wang, Zan; Liu, Duan; Shi, Yongmei; Xu, Lin; Zhang, Zhijun

    2016-01-01

    The apolipoprotein E (APOE) ε4 allele associates with accelerating the conversion from amnestic mild cognitive impairment (aMCI) to Alzheimer's disease (AD), whereas the protectiveAPOEε2 allele appears to be against the disease. Moreover, entorhinal cortex (ERC) is one of the earliest brain regions of AD pathology that disrupts the formation of episodic memory. To investigate the effects of APOE ε2 and ε4alleles on functional connectivity (FC) of ERC and cognition in aMCI. Methods The FC analyses of ERC were performed in 83 aMCI (9 ε2-carrier, 44 ε3ε3, and 30 ε4-carrier) and 88 healthy controls (HC, 15 ε2-carrier, 40 ε3ε3, and 33 ε4-carrier). Multiple linear regression model was performed between the altered ERC connectivities and cognition. In the ERC network, aMCI with ε4-carriers showed decreased FC in the bilateral middle temporal gyrus (MTG), right precuneus, and right precentral gyrus (PreCG), while ε2-carriers showed increased FC in these regions (except the right PreCG) compared to HC. The altered FC between ERC and right MTG correlated with episodic memory performance in aMCI carried ε2 and ε4 alleles. These results suggest that the effects ofAPOEon the ERC network are closely linked to the role of this gene on AD risk, which aMCI with ε4-carriers can accelerate the pathological progression of network-based mechanisms while ε2-carriers may play a protective role in contributing to a compensatory mechanism. It further suggests that APOE can appear to directly affect the ERC-MTG neural pathway associated with the impairment of episodic memory in aMCI. PMID:27542235

  10. Significance of autobiographical episodes and spacing effects in incidental memory.

    PubMed

    Toyota, Hiroshi

    2013-10-01

    Participants were presented with target words on two occasions, and were asked each time to generate a memory of a past episode associated with the targets. Participants were also instructed to rate the importance (significance elaboration) or pleasantness of the pisode (pleasantness elaboration) in an orienting task, followed by an unexpect d recall test. Significance elaboration led to better recall than pleasantness elaboration, but only in the spaced presentation. The spaced presentation led to better tree recall than massed presentation with significance elaboration, but the difference between the two types of presentation was not observed with pleasantness elaboration. These results suggest that the significance of an episode is more critical than the pleasantness of an episode in determining the effectiveness of autobiographical elaboration in facilitating recall.

  11. Effects on incidental memory of affective tone in associated past and future episodes: influence of emotional intelligence.

    PubMed

    Toyota, Hiroshi

    2011-02-01

    The present study examined the effects of emotion elicited by episodes (past events or expected future events) and the relationship between individual differences in emotional intelligence and memory. Participants' emotional intelligence was assessed on the Japanese version of Emotional Skills and Competence Questionnaire. They rated the pleasantness of episodes they associated with targets, and then performed unexpected free recall tests. When the targets were associated with episodes that were past events, all participants recalled more of the targets associated with pleasant and unpleasant episodes than those associated with neutral episodes. However, when the targets were associated with episodes expected to occur in the future, only participants with higher emotional intelligence scores recalled more of the targets associated with pleasant and unpleasant episodes. The participants with lower emotional intelligence scores recalled the three target types with similar accuracy. These results were interpreted as showing that emotional intelligence is associated with the processing of targets associated with future episodes as retrieval cues.

  12. Common Genetic Variants on 6q24 Associated With Exceptional Episodic Memory Performance in the Elderly

    PubMed Central

    Barral, Sandra; Cosentino, Stephanie; Christensen, Kaare; Newman, Anne B.; Perls, Thomas T.; Province, Michael A.; Mayeux, Richard

    2015-01-01

    IMPORTANCE There aregenetic influences on memory ability as we age. but no specific genes have been identified. OBJECTIVE To use a cognitive endophenotype. exceptional episodic memory(EEM) performance. derived from nondemented offspring from the Long Life FamilyStudy(LLFS) to identify genetic variants that may be responsible for the high cognitive performance of LLFS participants and further replicate these variants using an additional 4006 nondemented individuals from 4 independent elderly cohorts DESIGN, SETTING, AND PARTICIPANTS A total of 467 LLFS participants from 18 families with 2 or more offspring that exhibited exceptional memory performance were used for genome-wide linkage analysis Adjusted multivariate linear analyses in the 40-megabase region encompassing the linkage peak were conducted using 4 independent replication data sets that included 4006 nondemented elderly individuals. Results of the individual replication cohorts were combined by meta-analysis MAIN OUTCOME MEASURE Episodic memory scores computed as the mean of the 2 standardized measures of Logical Memory IA and IIA RESULTS Heritability estimates indicated a significant genetic component for E EM (h2 = 0.21; SE = 0.09) Genome-wide linkage analysis revealed that EEM was linked to the 6q24 region (maximum logarithm of odds score, 3.64) Association analysis in LLFS families identified single-nucleotide polymorphisms (SNPs) nominally associated with EEM in the 40-megabase window encompassing the linkage peak Replication in one cohort identified a set of 26 SNPs associated with episodic memory (P ≤ 05) Meta-analysis of the 26 SNPs using the 4 independent replication cohorts found SN Ps rs9321334 and rs6902875 to be nominally significantly associated with episodic memory (P= .009 and P = .013. respectively). With meta-analysis restricted to individuals lacking an APOE ε4 allele. SNP rs6902875 became statistically significant (meta-analysis. P = 6.7 × 10−5) Haplotypeanalysis incorporating the

  13. 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.

  14. 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…

  15. Altered Episodic Memory in Introverted Young Adults Carrying the BDNFMet Allele

    PubMed Central

    Bombardier, Andreanne; Beauchemin, Maude; Gosselin, Nadia; Poirier, Judes; De Beaumont, Louis

    2016-01-01

    While most studies have been interested in the distinct, predisposing roles of the common BDNF Val66Met variant and extraversion personality traits on episodic memory, very few studies have looked at the synergistic effects of genetic and personality factors to account for cognitive variance. This is surprising considering recent reports challenging the long-held belief that the BDNFMet variant negatively impacts cognitive function. A total of 75 young healthy adults (26 of them carried at least one copy of the BDNFMet allele) took part in this study consisting of genetic profiling from saliva, personality assessment using the Revised NEO Personality Inventory (NEO PI-R) and a short battery of neuropsychological tests. An ANOVA revealed that BDNFMet carriers were significantly less extraverted than BDNFVal carriers (F1,73 = 9.54; p < 0.01; ηp2 = 0.126). Moreover, extraversion was found to significantly moderate the relationship between the BDNF genotype and episodic memory performance (p = 0.03). Subsequent correlational analyses yielded a strong and significant correlation (r = 0.542; p < 0.005) between introversion and delayed episodic memory specific to BDNFMet individuals. The present study suggests that introversion and the BDNFMet variant synergistically interact to reduce episodic memory performance in healthy, young adults. These findings reaffirm that a more accurate explanation of cognitive variance can be achieved by looking at the synergistic effects of genotype and phenotype factors. PMID:27845759

  16. The Multifold Relationship between Memory and Decision Making: An Individual-Differences Study

    ERIC Educational Resources Information Center

    Del Missier, Fabio; Mäntylä, Timo; Hansson, Patrik; Bruine de Bruin, Wändi; Parker, Andrew M.; Nilsson, Lars-Göran

    2013-01-01

    Several judgment and decision-making tasks are assumed to involve memory functions, but significant knowledge gaps on the memory processes underlying these tasks remain. In a study on 568 adults between 25 and 80 years of age, hypotheses were tested on the specific relationships between individual differences in working memory, episodic memory,…

  17. 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.

  18. Episodic Memory on the Path to Alzheimer’s Disease

    PubMed Central

    Gallagher, Michela; Koh, Ming Teng

    2011-01-01

    This review is focused on specific circuits of the medial temporal lobe that have become better understood in recent years for their computational properties contributing to episodic memory and to memory impairment associated with aging and other risk for AD. The layer II neurons in the entorhinal cortex and their targets in the dentate gyrus and CA3 region of hippocampus comprise a system that rapidly encodes representations that are distinct from prior memories. Frank neuron loss in the entorhinal cortex is specific for AD, and related structural and functional changes across the network comprised of the entorhinal cortex and the dentate/CA3 regions hold promise for predicting progression on the path to AD. PMID:22079495

  19. Transformed Neural Pattern Reinstatement during Episodic Memory Retrieval.

    PubMed

    Xiao, Xiaoqian; Dong, Qi; Gao, Jiahong; Men, Weiwei; Poldrack, Russell A; Xue, Gui

    2017-03-15

    Contemporary models of episodic memory posit that remembering involves the reenactment of encoding processes. Although encoding-retrieval similarity has been consistently reported and linked to memory success, the nature of neural pattern reinstatement is poorly understood. Using high-resolution fMRI on human subjects, our results obtained clear evidence for item-specific pattern reinstatement in the frontoparietal cortex, even when the encoding-retrieval pairs shared no perceptual similarity. No item-specific pattern reinstatement was found in the ventral visual cortex. Importantly, the brain regions and voxels carrying item-specific representation differed significantly between encoding and retrieval, and the item specificity for encoding-retrieval similarity was smaller than that for encoding or retrieval, suggesting different nature of representations between encoding and retrieval. Moreover, cross-region representational similarity analysis suggests that the encoded representation in the ventral visual cortex was reinstated in the frontoparietal cortex during retrieval. Together, these results suggest that, in addition to reinstatement of the originally encoded pattern in the brain regions that perform encoding processes, retrieval may also involve the reinstatement of a transformed representation of the encoded information. These results emphasize the constructive nature of memory retrieval that helps to serve important adaptive functions.SIGNIFICANCE STATEMENT Episodic memory enables humans to vividly reexperience past events, yet how this is achieved at the neural level is barely understood. A long-standing hypothesis posits that memory retrieval involves the faithful reinstatement of encoding-related activity. We tested this hypothesis by comparing the neural representations during encoding and retrieval. We found strong pattern reinstatement in the frontoparietal cortex, but not in the ventral visual cortex, that represents visual details. Critically

  20. Deeper processing is beneficial during episodic memory encoding for adults with Williams syndrome.

    PubMed

    Greer, Joanna; Hamiliton, Colin; Riby, Deborah M; Riby, Leigh M

    2014-07-01

    Previous research exploring declarative memory in Williams syndrome (WS) has revealed impairment in the processing of episodic information accompanied by a relative strength in semantic ability. The aim of the current study was to extend this literature by examining how relatively spared semantic memory may support episodic remembering. Using a level of processing paradigm, older adults with WS (aged 35-61 years) were compared to typical adults of the same chronological age and typically developing children matched for verbal ability. In the study phase, pictures were encoded using either a deep (decide if a picture belongs to a particular category) or shallow (perceptual based processing) memory strategy. Behavioural indices (reaction time and accuracy) at retrieval were suggestive of an overall difficulty in episodic memory for WS adults. Interestingly, however, semantic support was evident with a greater recall of items encoded with deep compared to shallow processing, indicative of an ability to employ semantic encoding strategies to maximise the strength of the memory trace created. Unlike individuals with autism who find semantic elaboration strategies problematic, the pattern of findings reported here suggests in those domains that are relatively impaired in WS, support can be recruited from relatively spared cognitive processes.

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

    PubMed

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

    2015-01-01

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

  2. The Emergence of Primary Anoetic Consciousness in Episodic Memory

    PubMed Central

    Vandekerckhove, Marie; Bulnes, Luis Carlo; Panksepp, Jaak

    2014-01-01

    Based on an interdisciplinary perspective, we discuss how primary-process, anoetic forms of consciousness emerge into higher forms of awareness such as knowledge-based episodic knowing and self-aware forms of higher-order consciousness like autonoetic awareness. Anoetic consciousness is defined as the rudimentary state of affective, homeostatic, and sensory-perceptual mental experiences. It can be considered as the autonomic flow of primary-process phenomenal experiences that reflects a fundamental form of first-person “self-experience,” a vastly underestimated primary form of phenomenal consciousness. We argue that this anoetic form of evolutionarily refined consciousness constitutes a critical antecedent that is foundational for all forms of knowledge acquisition via learning and memory, giving rise to a knowledge-based, or noetic, consciousness as well as higher forms of “awareness” or “knowing consciousness” that permits “time-travel” in the brain-mind. We summarize the conceptual advantages of such a multi-tiered neuroevolutionary approach to psychological issues, namely from genetically controlled primary (affective) and secondary (learning and memory), to higher tertiary (developmentally emergent) brain-mind processes, along with suggestions about how affective experiences become more cognitive and object-oriented, allowing the developmental creation of more subtle higher mental processes such as episodic memory which allows the possibility of autonoetic consciousness, namely looking forward and backward at one’s life and its possibilities within the “mind’s eye.” PMID:24427125

  3. Cognitive dissonance resolution is related to episodic memory.

    PubMed

    Salti, Moti; El Karoui, Imen; Maillet, Mathurin; Naccache, Lionel

    2014-01-01

    The notion that our past choices affect our future behavior is certainly one of the most influential concepts of social psychology since its first experimental report in the 50 s, and its initial theorization by Festinger within the "cognitive dissonance" framework. Using the free choice paradigm (FCP), it was shown that choosing between two similarly rated items made subjects reevaluate the chosen items as more attractive and the rejected items as less attractive. However, in 2010 a major work by Chen and Risen revealed a severe statistical flaw casting doubt on most previous studies. Izuma and colleagues (2010) supplemented the traditional FCP with original control conditions and concluded that the effect observed could not be solely attributed to this methodological flaw. In the present work we aimed at establishing the existence of genuine choice-induced preference change and characterizing this effect. To do so, we replicated Izuma et al.' study and added a new important control condition which was absent from the original study. Moreover, we added a memory test in order to measure the possible relation between episodic memory of choices and observed behavioral effects. In two experiments we provide experimental evidence supporting genuine choice-induced preference change obtained with FCP. We also contribute to the understanding of the phenomenon by showing that choice-induced preference change effects are strongly correlated with episodic memory.

  4. Cognitive Dissonance Resolution Is Related to Episodic Memory

    PubMed Central

    Maillet, Mathurin; Naccache, Lionel

    2014-01-01

    The notion that our past choices affect our future behavior is certainly one of the most influential concepts of social psychology since its first experimental report in the 50 s, and its initial theorization by Festinger within the “cognitive dissonance” framework. Using the free choice paradigm (FCP), it was shown that choosing between two similarly rated items made subjects reevaluate the chosen items as more attractive and the rejected items as less attractive. However, in 2010 a major work by Chen and Risen revealed a severe statistical flaw casting doubt on most previous studies. Izuma and colleagues (2010) supplemented the traditional FCP with original control conditions and concluded that the effect observed could not be solely attributed to this methodological flaw. In the present work we aimed at establishing the existence of genuine choice-induced preference change and characterizing this effect. To do so, we replicated Izuma et al.’ study and added a new important control condition which was absent from the original study. Moreover, we added a memory test in order to measure the possible relation between episodic memory of choices and observed behavioral effects. In two experiments we provide experimental evidence supporting genuine choice-induced preference change obtained with FCP. We also contribute to the understanding of the phenomenon by showing that choice-induced preference change effects are strongly correlated with episodic memory. PMID:25264950

  5. 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…

  6. Toward a model of cognitive insight in first-episode psychosis: verbal memory and hippocampal structure.

    PubMed

    Buchy, L; Czechowska, Y; Chochol, C; Malla, A; Joober, R; Pruessner, J; Lepage, M

    2010-09-01

    Our previous work has linked verbal learning and memory with cognitive insight, but not clinical insight, in individuals with a first-episode psychosis (FEP). The current study reassessed the neurocognitive basis of cognitive and clinical insight and explored their neural basis in 61 FEP patients. Cognitive insight was measured with the Beck Cognitive Insight Scale (BCIS) and clinical insight with the Scale to assess Unawareness of Mental Disorder (SUMD). Global measures for 7 domains of cognition were examined. Hippocampi were manually segmented in to 3 parts: the body, head, and tail. Verbal learning and memory significantly correlated with the BCIS composite index. Composite index scores were significantly associated with total left hippocampal (HC) volume; partial correlations, however, revealed that this relationship was attributable largely to verbal memory performance. The BCIS self-certainty subscale significantly and inversely correlated with bilateral HC volumes, and these associations were independent of verbal learning and memory performance. The BCIS self-reflectiveness subscale significantly correlated with verbal learning and memory but not with HC volume. No significant correlations emerged between the SUMD and verbal memory or HC volume. These results strengthen our previous assertion that in individuals with an FEP cognitive insight may rely on memory whereby current experiences are appraised based on previous ones. The HC may be a viable location among others for the brain system that underlies aspects of cognitive insight in individuals with an FEP.

  7. Individuals with episodic amnesia are not stuck in time.

    PubMed

    Craver, Carl F; Kwan, Donna; Steindam, Chloe; Rosenbaum, R Shayna

    2014-05-01

    The metaphor that individuals with episodic amnesia due to hippocampal damage are "stuck in time" persists in science, philosophy, and everyday life despite mounting evidence that episodic amnesia can spare many central aspects of temporal consciousness. Here we describe some of this evidence, focusing specifically on KC, one of the most thoroughly documented and severe cases of episodic amnesia on record. KC understands the concept of time, knows that it passes, and can orient himself with respect to his personal past and future. He expresses typical attitudes toward his past and future, and he is able to make future-regarding decisions. Theories claiming that the hippocampus plays an essential role in temporal consciousness need to be revised in light of these findings.

  8. 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),…

  9. 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…

  10. 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…

  11. 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…

  12. Recollection in an Episodic-Like Memory Task in the Rat

    ERIC Educational Resources Information Center

    Zinkivskay, Ann; Eacott, Madeline J.; Easton, Alexander

    2005-01-01

    Episodic memory in humans is the conscious recollection of a past event. Animal models of episodic-like memory assess the memory for "what" happened, "where" it happened, and either "when" it happened, or in "which" context it happened, although recollection on such tasks is often difficult to measure. Here we present the first evidence of…

  13. Generalization Through the Recurrent Interaction of Episodic Memories

    PubMed Central

    Kumaran, Dharshan; McClelland, James L.

    2012-01-01

    In this article, we present a perspective on the role of the hippocampal system in generalization, instantiated in a computational model called REMERGE (recurrency and episodic memory results in generalization). We expose a fundamental, but neglected, tension between prevailing computational theories that emphasize the function of the hippocampus in pattern separation (Marr, 1971; McClelland, McNaughton, & O'Reilly, 1995), and empirical support for its role in generalization and flexible relational memory (Cohen & Eichenbaum, 1993; Eichenbaum, 1999). Our account provides a means by which to resolve this conflict, by demonstrating that the basic representational scheme envisioned by complementary learning systems theory (McClelland et al., 1995), which relies upon orthogonalized codes in the hippocampus, is compatible with efficient generalization—as long as there is recurrence rather than unidirectional flow within the hippocampal circuit or, more widely, between the hippocampus and neocortex. We propose that recurrent similarity computation, a process that facilitates the discovery of higher-order relationships between a set of related experiences, expands the scope of classical exemplar-based models of memory (e.g., Nosofsky, 1984) and allows the hippocampus to support generalization through interactions that unfold within a dynamically created memory space. PMID:22775499

  14. Conscious Experience and Episodic Memory: Hippocampus at the Crossroads

    PubMed Central

    Behrendt, Ralf-Peter

    2013-01-01

    If an instance of conscious experience of the seemingly objective world around us could be regarded as a newly formed event memory, much as an instance of mental imagery has the content of a retrieved event memory, and if, therefore, the stream of conscious experience could be seen as evidence for ongoing formation of event memories that are linked into episodic memory sequences, then unitary conscious experience could be defined as a symbolic representation of the pattern of hippocampal neuronal firing that encodes an event memory – a theoretical stance that may shed light into the mind-body and binding problems in consciousness research. Exceedingly detailed symbols that describe patterns of activity rapidly self-organizing, at each cycle of the θ rhythm, in the hippocampus are instances of unitary conscious experience that jointly constitute the stream of consciousness. Integrating object information (derived from the ventral visual stream and orbitofrontal cortex) with contextual emotional information (from the anterior insula) and spatial environmental information (from the dorsal visual stream), the hippocampus rapidly forms event codes that have the informational content of objects embedded in an emotional and spatiotemporally extending context. Event codes, formed in the CA3-dentate network for the purpose of their memorization, are not only contextualized but also allocentric representations, similarly to conscious experiences of events and objects situated in a seemingly objective and observer-independent framework of phenomenal space and time. Conscious perception, creating the spatially and temporally extending world that we perceive around us, is likely to be evolutionarily related to more fleeting and seemingly internal forms of conscious experience, such as autobiographical memory recall, mental imagery, including goal anticipation, and to other forms of externalized conscious experience, namely dreaming and hallucinations; and evidence pointing

  15. Conscious experience and episodic memory: hippocampus at the crossroads.

    PubMed

    Behrendt, Ralf-Peter

    2013-01-01

    If an instance of conscious experience of the seemingly objective world around us could be regarded as a newly formed event memory, much as an instance of mental imagery has the content of a retrieved event memory, and if, therefore, the stream of conscious experience could be seen as evidence for ongoing formation of event memories that are linked into episodic memory sequences, then unitary conscious experience could be defined as a symbolic representation of the pattern of hippocampal neuronal firing that encodes an event memory - a theoretical stance that may shed light into the mind-body and binding problems in consciousness research. Exceedingly detailed symbols that describe patterns of activity rapidly self-organizing, at each cycle of the θ rhythm, in the hippocampus are instances of unitary conscious experience that jointly constitute the stream of consciousness. Integrating object information (derived from the ventral visual stream and orbitofrontal cortex) with contextual emotional information (from the anterior insula) and spatial environmental information (from the dorsal visual stream), the hippocampus rapidly forms event codes that have the informational content of objects embedded in an emotional and spatiotemporally extending context. Event codes, formed in the CA3-dentate network for the purpose of their memorization, are not only contextualized but also allocentric representations, similarly to conscious experiences of events and objects situated in a seemingly objective and observer-independent framework of phenomenal space and time. Conscious perception, creating the spatially and temporally extending world that we perceive around us, is likely to be evolutionarily related to more fleeting and seemingly internal forms of conscious experience, such as autobiographical memory recall, mental imagery, including goal anticipation, and to other forms of externalized conscious experience, namely dreaming and hallucinations; and evidence pointing to

  16. 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.

  17. Video Game Training Enhances Visuospatial Working Memory and Episodic Memory in Older Adults

    PubMed Central

    Toril, Pilar; Reales, José M.; Mayas, Julia; Ballesteros, Soledad

    2016-01-01

    In this longitudinal intervention study with experimental and control groups, we investigated the effects of video game training on the visuospatial working memory (WM) and episodic memory of healthy older adults. Participants were 19 volunteer older adults, who received 15 1-h video game training sessions with a series of video games selected from a commercial package (Lumosity), and a control group of 20 healthy older adults. The results showed that the performance of the trainees improved significantly in all the practiced video games. Most importantly, we found significant enhancements after training in the trained group and no change in the control group in two computerized tasks designed to assess visuospatial WM, namely the Corsi blocks task and the Jigsaw puzzle task. The episodic memory and short-term memory of the trainees also improved. Gains in some WM and episodic memory tasks were maintained during a 3-month follow-up period. These results suggest that the aging brain still retains some degree of plasticity, and that video game training might be an effective intervention tool to improve WM and other cognitive functions in older adults. PMID:27199723

  18. Video Game Training Enhances Visuospatial Working Memory and Episodic Memory in Older Adults.

    PubMed

    Toril, Pilar; Reales, José M; Mayas, Julia; Ballesteros, Soledad

    2016-01-01

    In this longitudinal intervention study with experimental and control groups, we investigated the effects of video game training on the visuospatial working memory (WM) and episodic memory of healthy older adults. Participants were 19 volunteer older adults, who received 15 1-h video game training sessions with a series of video games selected from a commercial package (Lumosity), and a control group of 20 healthy older adults. The results showed that the performance of the trainees improved significantly in all the practiced video games. Most importantly, we found significant enhancements after training in the trained group and no change in the control group in two computerized tasks designed to assess visuospatial WM, namely the Corsi blocks task and the Jigsaw puzzle task. The episodic memory and short-term memory of the trainees also improved. Gains in some WM and episodic memory tasks were maintained during a 3-month follow-up period. These results suggest that the aging brain still retains some degree of plasticity, and that video game training might be an effective intervention tool to improve WM and other cognitive functions in older adults.

  19. Spontaneous or intentional? Involuntary versus voluntary episodic memories in older and younger adults.

    PubMed

    Berntsen, Dorthe; Rasmussen, Anne S; Miles, Amanda N; Nielsen, Niels Peter; Ramsgaard, Stine B

    2017-03-01

    Involuntary episodic memories are memories of past events that come to mind with no preceding attempt of retrieval. Such memories have received little attention in relation to aging compared with voluntary episodic memories (i.e., intentionally retrieved memories of past events). It is well documented that older compared with younger adults have reduced access to episodic memories, when retrieval is voluntary, but little is known about their involuntary episodic recall. Recent evidence suggests that involuntary autobiographical memories are at least as frequent as voluntary autobiographical memories in daily life, but this research has been limited to younger adults. Here older and younger adults recorded involuntary and voluntary episodic memories in relation to a film of a simulated event (Study 1) and during a normal day in their lives (Study 2). Across both studies, no age differences were found regarding the frequency of involuntary episodic memories, whereas older adults showed slower (Study 1) and less frequent (Study 2) voluntary remembering compared with younger adults. The findings suggest that involuntary relative to voluntary episodic remembering is enhanced in older adults, consistent with reduced executive functioning and increased processing of task irrelevant information with aging. Involuntary episodic remembering may provide an adaptive compensation for reductions in strategic retrieval in later adulthood. (PsycINFO Database Record

  20. 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,…

  1. Are animacy effects in episodic memory independent of encoding instructions?

    PubMed

    Gelin, Margaux; Bugaiska, Aurélia; Méot, Alain; Bonin, Patrick

    2017-01-01

    The adaptive view of human memory [Nairne, J. S. 2010. Adaptive memory: Evolutionary constraints on remembering. In B. H. Ross (Ed.), The psychology of learning and motivation (Vol. 53 pp. 1-32). Burlington: Academic Press; Nairne, J. S., & Pandeirada, J. N. S. 2010a. Adaptive memory: Ancestral priorities and the mnemonic value of survival processing. Cognitive Psychology, 61, 1-22, 2010b; Memory functions. In The Corsini encyclopedia of psychology and behavioral science, (Vol 3, 4th ed. pp. 977-979). Hokoben, NJ: John Wiley & Sons] assumes that animates (e.g., baby, rabbit presented as words or pictures) are better remembered than inanimates (e.g., bottle, mountain) because animates are more important for fitness than inanimates. In four studies, we investigated whether the animacy effect in episodic memory (i.e., the better remembering of animates over inanimates) is independent of encoding instructions. Using both a factorial (Studies 1 and 3) and a multiple regression approach (Study 2), three studies tested whether certain contexts drive people to attend to inanimate more than to animate things (or the reverse), and therefore lead to differential animacy effects. The findings showed that animacy effects on recall performance were observed in the grassland-survival scenario used by Nairne, Thompson, and Pandeirada (2007. Adaptive memory: Survival processing enhances retention. Journal of Experimental Psychology: Learning, Memory, & Cognition, 33, 263-273) (Studies 1-3), when words were rated for their pleasantness (Study 2), and in explicit learning (Study 3). In the non-survival scenario of moving to a foreign land (Studies 1-2), animacy effects on recall rates were not reliable in Study 1, but were significant in Study 2, whereas these effects were reliable in the non-survival scenario of planning a trip as a tour guide (Study 3). A final (control) study (Study 4) was conducted to test specifically whether animacy effects are related to the more organised

  2. The parallel impact of episodic memory and episodic future thinking on food intake.

    PubMed

    Vartanian, Lenny R; Chen, William H; Reily, Natalie M; Castel, Alan D

    2016-06-01

    This research examined the effects of both episodic memory and episodic future thinking (EFT) on snack food intake. In Study 1, female participants (n = 158) were asked to recall their lunch from earlier in the day, to think about the dinner they planned to have later in the day, or to think about a non-food activity before taking part in a cookie taste test. Participants who recalled their lunch or who thought about their dinner ate less than did participants who thought about non-food activities. These effects were not explained by group differences in the hedonic value of the food. Study 2 examined whether the suppression effect observed in Study 1 was driven by a general health consciousness. Female participants (n = 74) were asked to think about their past or future exercise (or a non-exercise activity), but thinking about exercise had no impact on participants' cookie consumption. Overall, both thinking about past food intake and imagining future food intake had the same suppression effect on participants' current food intake, but further research is needed to determine the underlying mechanism.

  3. No Associations between Interindividual Differences in Sleep Parameters and Episodic Memory Consolidation

    PubMed Central

    Ackermann, Sandra; Hartmann, Francina; Papassotiropoulos, Andreas; de Quervain, Dominique J.F.; Rasch, Björn

    2015-01-01

    Study Objectives: Sleep and memory are stable and heritable traits that strongly differ between individuals. Sleep benefits memory consolidation, and the amount of slow wave sleep, sleep spindles, and rapid eye movement sleep have been repeatedly identified as reliable predictors for the amount of declarative and/or emotional memories retrieved after a consolidation period filled with sleep. These studies typically encompass small sample sizes, increasing the probability of overestimating the real association strength. In a large sample we tested whether individual differences in sleep are predictive for individual differences in memory for emotional and neutral pictures. Design: Between-subject design. Setting: Cognitive testing took place at the University of Basel, Switzerland. Sleep was recorded at participants' homes, using portable electroencephalograph-recording devices. Participants: Nine hundred-twenty-nine healthy young participants (mean age 22.48 ± 3.60 y standard deviation). Interventions: None. Measurements and results: In striking contrast to our expectations as well as numerous previous findings, we did not find any significant correlations between sleep and memory consolidation for pictorial stimuli. Conclusions: Our results indicate that individual differences in sleep are much less predictive for pictorial memory processes than previously assumed and suggest that previous studies using small sample sizes might have overestimated the association strength between sleep stage duration and pictorial memory performance. Future studies need to determine whether intraindividual differences rather than interindividual differences in sleep stage duration might be more predictive for the consolidation of emotional and neutral pictures during sleep. Citation: Ackermann S, Hartmann F, Papassotiropoulos A, de Quervain DJF, Rasch B. No associations between interindividual differences in sleep parameters and episodic memory consolidation. SLEEP 2015;38(6):951

  4. Episodic memory retrieval for story characters in high-functioning autism

    PubMed Central

    2013-01-01

    Background The objective of this study was to examine differences in episodic memory retrieval between individuals with autism spectrum disorder (ASD) and typically developing (TD) individuals. Previous studies have shown that personality similarities between readers and characters facilitated reading comprehension. Highly extraverted participants read stories featuring extraverted protagonists more easily and judged the outcomes of such stories more rapidly than did less extraverted participants. Similarly, highly neurotic participants judged the outcomes of stories with neurotic protagonists more rapidly than did participants with low levels of neuroticism. However, the impact of the similarity effect on memory retrieval remains unclear. This study tested our ‘similarity hypothesis’, namely that memory retrieval is enhanced when readers with ASD and TD readers read stories featuring protagonists with ASD and with characteristics associated with TD individuals, respectively. Methods Eighteen Japanese individuals (one female) with high-functioning ASD (aged 17 to 40 years) and 17 age- and intelligence quotient (IQ)-matched Japanese (one female) TD participants (aged 22 to 40 years) read 24 stories; 12 stories featured protagonists with ASD characteristics, and the other 12 featured TD protagonists. Participants read a single sentence at a time and pressed a spacebar to advance to the next sentence. After reading all 24 stories, they were asked to complete a recognition task about the target sentence in each story. Results To investigate episodic memory in ASD, we analyzed encoding based on the reading times for and readability of the stories and retrieval processes based on the accuracy of and response times for sentence recognition. Although the results showed no differences between ASD and TD groups in encoding processes, they did reveal inter-group differences in memory retrieval. Although individuals with ASD demonstrated the same level of accuracy as did

  5. 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…

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

    PubMed Central

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

    2015-01-01

    Objective HIV-associated deficits in verbal episodic memory are commonly associated with antiretroviral non-adherence; however, the specific aspects of memory functioning (e.g., encoding, consolidation, or retrieval) that underlie this established relationship are not well understood. Method This study evaluated verbal memory profiles of 202 HIV+ participants who underwent a 30-day electronic monitoring of antiretroviral adherence. Results At the group level, non-adherence was significantly associated with lower scores on immediate and delayed passage recall and word list learning. Retention and recognition of passages and word lists were not related to adherence. Participants were then classified as having either a normal verbal memory profile, a “subcortical” retrieval profile (i.e., impaired free recall with relatively spared recognition), or a “cortical” encoding profile (e.g., cued recall intrusions) based on the Massman et al. (1990) algorithm for the California Verbal Learning Test. HIV+ participants with a classic retrieval deficit had significantly greater odds of being non-adherent than participants with a normal or encoding profile. Conclusions These findings suggest that adherence to prescribed antiretroviral regimens may be particularly vulnerable to disruption in HIV+ individuals due to deficits in the complex process of efficiently accessing verbal episodic information with minimal cues. A stronger relationship between non-adherence and passage (vs. word list) recall was also found and may reflect the importance of contextual features in remembering to take medications. Targeted interventions for enhancing and supporting episodic memory retrieval processes may improve antiretroviral adherence and overall health outcomes among persons living with HIV. PMID:25781903

  7. 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

  8. Conjunction Illusions and Conjunction Fallacies in Episodic Memory

    PubMed Central

    Brainerd, C. J.; Holliday, R. E.; Nakamura, K.; Reyna, V. F.

    2014-01-01

    Recent research on the overdistribution principle implies that episodic memory is infected by conjunction illusions. These are instances in which an item that was presented in a single context (e.g., List 1) is falsely remembered as having been presented in multiple contexts (e.g., List 1 and List 2). Robust conjunction illusions were detected in source-monitoring designs in which conjunctive probes (Was bagpipe presented on List 1 and List 2?) were added to the traditional nonconjunctive probes (Was bagpipe presented on List 1?). In Experiment 1, the levels of those illusions were comparable to what would be expected on the basis of results from prior overdistribution experiments. In Experiments 2 and 3, conjunction illusions were neither eliminated nor reduced by a manipulation that should have had such effects if the illusions are by-products of subjective differences in retrieved memory support. Also, conjunction illusions sometimes rose to the level of conjunction fallacies: In certain conditions, subjects thought that items were more likely to have occurred in all the presentation contexts than in any single context, which is impossible. Two general approaches to explaining overdistribution, representational accounts and retrieval accounts, are considered. PMID:24911136

  9. Mood congruity and episodic memory in young children.

    PubMed

    Christodoulou, Joan; Burke, Deborah M

    2016-02-01

    Although mood congruity effects on episodic memory have been reported extensively in adults, they have not been reported for children younger than 10 years. The current research investigated mood congruity effects in story recall using an embodied approach to mood induction involving a facial manipulation task with 3- and 4-year-old children. Participants held a chopstick or a popsicle stick in their mouths in a way to either produce or inhibit a smile while they listened to a story featuring happy events for a happy character and sad events for a sad character. Children's mood ratings before and after mood induction indicated that mood became more positive in the smile condition, with no change in the no smile condition. Children in the smile condition, but not in the no smile condition, remembered more about the happy character than the sad character in the story. These results extend mood congruity effects to 3- and 4-year olds, suggesting that at this age representations of emotion interact with basic memory processes. Moreover, the efficacy of reenactment of sensorimotor components of emotion in modifying mood is consistent with embodied representation of emotion during early childhood.

  10. Positive and negative emotional contexts unevenly predict episodic memory.

    PubMed

    Martínez-Galindo, Joyce Graciela; Cansino, Selene

    2015-09-15

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

  11. 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…

  12. 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…

  13. Neural correlates of episodic memory: associative memory and confidence drive hippocampus activations.

    PubMed

    Kuchinke, Lars; Fritzemeier, Steffen; Hofmann, Markus J; Jacobs, Arthur M

    2013-10-01

    The present study used a study-test recognition memory task to examine the brain regions engaged in episodic and associative memory processes. Participants evaluated on a six-point rating scale how confident they were on whether or not an item was presented in a previous study phase. Neural activations for high- and low-confidence decisions were examined in old and new items at two levels of between-item-associations. Items had different amounts of associations within the stimulus set, while associations were defined by co-occurrence statistics. The medial frontal gyrus, the posterior cingulate gyrus, the superior temporal gyrus and the right hippocampus revealed U-shaped activation functions with greater activations for high-confidence OLD and NEW decisions. This was independent of the associative memory manipulation, which suggests that not episodic memory, but rather processes related to confidence account for the activation in these brain regions. In contrast, left hippocampus followed a different activation pattern that was modulated by the amount of associations. This provides evidence for the role of the left hippocampus in associative memory.

  14. When the future becomes the past: Differences in brain activation patterns for episodic memory and episodic future thinking.

    PubMed

    Weiler, Julia A; Suchan, Boris; Daum, Irene

    2010-10-15

    Episodic memory and episodic future thinking activate a network of overlapping brain regions, but little is known about the mechanism with which the brain separates the two processes. It was recently suggested that differential activity for memory and future thinking may be linked to differences in the phenomenal properties (e.g., richness of detail). Using functional magnetic resonance imaging in healthy subjects and a novel experimental design, we investigated the networks involved in the imagery of future and the recall of past events for the same target occasion, i.e. the Christmas and New Year's holidays, thereby keeping temporal distance and content similar across conditions. Although ratings of phenomenal characteristics were comparable for future thoughts and memories, differential activation patterns emerged. The right posterior hippocampus exhibited stronger memory-related activity during early event recall, and stronger future thought-related activity during late event imagination. Other regions, e.g., the precuneus and lateral prefrontal cortex, showed the reverse activation pattern with early future-associated and late past-associated activation. Memories compared to future thoughts were further related to stronger activation in several visual processing regions, which accords with a reactivation of the original perceptual experience. In conclusion, the results showed for the first time unique neural signatures for both memory and future thinking even in the absence of differences in phenomenal properties and suggested different time courses of brain activation for episodic memory and future thinking.

  15. 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.

  16. 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

  17. Frontotemporal Coherence and Executive Functions Contribute to Episodic Memory during Middle Childhood

    PubMed Central

    Blankenship, Tashauna L.; Bell, Martha Ann

    2016-01-01

    Contributions of differential behavioral (executive functions) and electrophysiological (frontal-temporal electroencephalogram or EEG coherence) measures to episodic memory performance were examined during middle childhood. Cognitive flexibility and right frontotemporal functional connectivity during encoding (F4/T8), as well as left frontotemporal functional connectivity during retrieval (Fp1/T7), contributed to episodic memory performance in a sample of 9–12 year olds. These results suggest that executive functions differentially influence episodic memory, as does left and right frontotemporal functional connectivity during different portions of the memory task. PMID:27043829

  18. 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

  19. Reinforcement Learning and Episodic Memory in Humans and Animals: An Integrative Framework.

    PubMed

    Gershman, Samuel J; Daw, Nathaniel D

    2017-01-03

    We review the psychology and neuroscience of reinforcement learning (RL), which has experienced significant progress in the past two decades, enabled by the comprehensive experimental study of simple learning and decision-making tasks. However, one challenge in the study of RL is computational: The simplicity of these tasks ignores important aspects of reinforcement learning in the real world: (a) State spaces are high-dimensional, continuous, and partially observable; this implies that (b) data are relatively sparse and, indeed, precisely the same situation may never be encountered twice; furthermore, (c) rewards depend on the long-term consequences of actions in ways that violate the classical assumptions that make RL tractable. A seemingly distinct challenge is that, cognitively, theories of RL have largely involved procedural and semantic memory, the way in which knowledge about action values or world models extracted gradually from many experiences can drive choice. This focus on semantic memory leaves out many aspects of memory, such as episodic memory, related to the traces of individual events. We suggest that these two challenges are related. The computational challenge can be dealt with, in part, by endowing RL systems with episodic memory, allowing them to (a) efficiently approximate value functions over complex state spaces, (b) learn with very little data, and (c) bridge long-term dependencies between actions and rewards. We review the computational theory underlying this proposal and the empirical evidence to support it. Our proposal suggests that the ubiquitous and diverse roles of memory in RL may function as part of an integrated learning system.

  20. Variation in Working Memory Capacity and Temporal-Contextual Retrieval from Episodic Memory

    ERIC Educational Resources Information Center

    Spillers, Gregory J.; Unsworth, Nash

    2011-01-01

    Unsworth and Engle (2007) recently proposed a model of working memory capacity characterized by, among other things, the ability to conduct a strategic, cue-dependent search of long-term memory. Although this ability has been found to mediate individual variation in a number of higher order cognitive tasks, the component processes involved remain…

  1. Mild Cognitive Impairment Is Not “Mild” at All in Altered Activation of Episodic Memory Brain Networks: Evidence from ALE Meta-Analysis

    PubMed Central

    Wang, Pengyun; Li, Juan; Li, Hui-Jie; Huo, Lijuan; Li, Rui

    2016-01-01

    The present study conducted a quantitative meta-analysis aiming at assessing consensus across the functional neuroimaging studies of episodic memory in individuals with amnestic mild cognitive impairment (aMCI) and elucidating consistent activation patterns. An activation likelihood estimation (ALE) was conducted on the functional neuroimaging studies of episodic encoding and retrieval in aMCI individuals published up to March 31, 2015. Analyses covered 24 studies, which yielded 770 distinct foci. Compared to healthy controls, aMCI individuals showed statistically significant consistent activation differences in a widespread episodic memory network, not only in the bilateral medial temporal lobe and prefrontal cortex, but also in the angular gyrus, precunes, posterior cingulate cortex, and even certain more basic structures. The present ALE meta-analysis revealed that the abnormal patterns of widespread episodic memory network indicated that individuals with aMCI may not be completely “mild” in nature. PMID:27872591

  2. Development in the Organization of Episodic Memories in Middle Childhood and Adolescence

    PubMed Central

    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. PMID:23874275

  3. 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.

  4. Mistakes as Stepping Stones: Effects of Errors on Episodic Memory among Younger and Older Adults

    ERIC Educational Resources Information Center

    Cyr, Andrée-Ann; Anderson, Nicole D.

    2015-01-01

    The memorial costs and benefits of trial-and-error learning have clear pedagogical implications for students, and increasing evidence shows that generating errors during episodic learning can improve memory among younger adults. Conversely, the aging literature has found that errors impair memory among healthy older adults and has advocated for…

  5. Computational Model-Based Prediction of Human Episodic Memory Performance Based on Eye Movements

    NASA Astrophysics Data System (ADS)

    Sato, Naoyuki; Yamaguchi, Yoko

    Subjects' episodic memory performance is not simply reflected by eye movements. We use a ‘theta phase coding’ model of the hippocampus to predict subjects' memory performance from their eye movements. Results demonstrate the ability of the model to predict subjects' memory performance. These studies provide a novel approach to computational modeling in the human-machine interface.

  6. Neural correlates of opposing effects of emotional distraction on working memory and episodic memory: an event-related FMRI investigation.

    PubMed

    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.

  7. Recovering and preventing loss of detailed memory: differential rates of forgetting for detail types in episodic memory

    PubMed Central

    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, while memory for central details is relatively spared. Given the sensitivity of memory to loss of details, the present study sought to investigate factors that mediate the forgetting of different types of information from naturalistic episodic memories in young healthy adults. The study investigated (1) time-dependent loss of “central” and “peripheral” details from episodic memories, (2) the effectiveness of cuing with reminders to reinstate memory details, and (3) the role of retrieval in preventing forgetting. Over the course of 7 d, memory for naturalistic events (film clips) underwent a time-dependent loss of peripheral details, while memory for central details (the core or gist of events) showed significantly less loss. Giving brief reminders of the clips just before retrieval reinstated memory for peripheral details, suggesting that loss of details is not always permanent, and may reflect both a storage and retrieval deficit. Furthermore, retrieving a memory shortly after it was encoded prevented loss of both central and peripheral details, thereby promoting retention over time. We consider the implications of these results for behavioral and neurobiological models of retention and forgetting. PMID:26773100

  8. Cross-cultural adaptation and validation of the episodic autobiographic memory interview for Brazilian Portuguese.

    PubMed

    Rodrigues, Guilherme R; Oliveira, Daniel S; Foss, Maria P; Takayanagui, Osvaldo M

    2015-08-01

    Episodic memory enables the storage of personal events with specific temporal and spatial details, and their retrieval through a sensory experience, usually visual, which is called autonoetic consciousness. While, in Brazil, several scales for the evaluation of anterograde episodic memory have been validated, there is not yet an instrument to assess the episodic autobiographical memory. The aim of this study is thus to make a cross-cultural adaptation and validation of the Episodic Autobiographic Memory Interview (EAMI) for Brazilian Portuguese. Altogether, 11 patients with Alzheimer's disease (AD) and 10 healthy controls (CTs) were evaluated. EAMI scores for AD patients were lower than those of CTs, and these scores also correlated positively with the Remember-Know coefficient. The intraclass correlation coefficient indicated a good inter-rater reliability. The Portuguese version of EAMI showed a good reliability and validity, which suggests that it is a useful tool for evaluation of autobiographical memory in Brazilian patients.

  9. 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.

  10. The "when" and the "where" of single-trial allocentric spatial memory performance in young children: Insights into the development of episodic memory.

    PubMed

    Ribordy Lambert, Farfalla; Lavenex, Pierre; Banta Lavenex, Pamela

    2017-03-01

    Allocentric spatial memory, "where" with respect to the surrounding environment, is one of the three fundamental components of episodic memory: what, where, when. Whereas basic allocentric spatial memory abilities are reliably observed in children after 2 years of age, coinciding with the offset of infantile amnesia, the resolution of allocentric spatial memory acquired over repeated trials improves from 2 to 4 years of age. Here, we first show that single-trial allocentric spatial memory performance improves in children from 3.5 to 7 years of age, during the typical period of childhood amnesia. Second, we show that large individual variation exists in children's performance at this age. Third, and most importantly, we show that improvements in single-trial allocentric spatial memory performance are due to an increasing ability to spatially and temporally separate locations and events. Such improvements in spatial and temporal processing abilities may contribute to the gradual offset of childhood amnesia.

  11. Neurofunctional correlates of environmental cognition: an FMRI study with images from episodic memory.

    PubMed

    Vedder, Aline; Smigielski, Lukasz; Gutyrchik, Evgeny; Bao, Yan; Blautzik, Janusch; Pöppel, Ernst; Zaytseva, Yuliya; Russell, Edmund

    2015-01-01

    This study capitalizes on individual episodic memories to investigate the question, how dif-ferent environments affect us on a neural level. Instead of using predefined environmental stimuli, this study relied on individual representations of beauty and pleasure. Drawing upon episodic memories we conducted two experiments. Healthy subjects imagined pleasant and non-pleasant environments, as well as beautiful and non-beautiful environments while neural activity was measured by using functional Magnetic Resonance Imaging. Although subjects found the different conditions equally simple to visualize, our results revealed more distribut-ed brain activations for non-pleasant and non-beautiful environments than for pleasant and beautiful environments. The additional regions activated in non-pleasant (left lateral prefrontal cortex) and non-beautiful environments (supplementary motor area, anterior cortical midline structures) are involved in self-regulation and top-down cognitive control. Taken together, the results show that perceptual experiences and emotional evaluations of environments within a positive and a negative frame of reference are based on distinct patterns of neural activity. We interpret the data in terms of a different cognitive and processing load placed by exposure to different environments. The results hint at the efficiency of subject-generated representations as stimulus material.

  12. Aspects of psychodynamic neuropsychiatry I: episodic memory, transference, and the oddball paradigm.

    PubMed

    Brockman, Richard

    2010-01-01

    Psychotherapy has, since the time of Freud, focused on the unconscious and dynamically repressed memory. This article explores a therapy where the focus is on what is known, on episodic memory. Episodic memory, along with semantic memory, is part of the declarative memory system. Episodic memory depends on frontal, parietal, as well as temporal lobe function. It is the system related to the encoding and recall of context-rich memory. While memory usually decays with time, powerfully encoded episodic memory may augment. This article explores the hypothesis that such augmentation is the result of conditioning and kindling. Augmented memory could lead to a powerful "top-down" focus of attention-such that one would perceive only what one had set out to perceive. The "oddball paradigm" is suggested as a route out of such a self-perpetuating system. A clinical example (a disguised composite of several clinical histories) is used to demonstrate how such an intensification of memory and attention came about as a result of the transference, and how the "oddball paradigm" was used as a way out of what had become a treatment stalemate.

  13. Episodic Memory Does Not Add Up: Verbatim-Gist Superposition Predicts Violations of the Additive Law of Probability

    PubMed Central

    Brainerd, C. J.; Wang, Zheng; Reyna, Valerie. F.; Nakamura, K.

    2015-01-01

    Fuzzy-trace theory’s assumptions about memory representation are cognitive examples of the familiar superposition property of physical quantum systems. When those assumptions are implemented in a formal quantum model (QEMc), they predict that episodic memory will violate the additive law of probability: If memory is tested for a partition of an item’s possible episodic states, the individual probabilities of remembering the item as belonging to each state must sum to more than 1. We detected this phenomenon using two standard designs, item false memory and source false memory. The quantum implementation of fuzzy-trace theory also predicts that violations of the additive law will vary in strength as a function of reliance on gist memory. That prediction, too, was confirmed via a series of manipulations (e.g., semantic relatedness, testing delay) that are thought to increase gist reliance. Surprisingly, an analysis of the underlying structure of violations of the additive law revealed that as a general rule, increases in remembering correct episodic states do not produce commensurate reductions in remembering incorrect states. PMID:26236091

  14. 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.

  15. Pulse Pressure Magnifies the Effect of COMT Val158Met on 15 Years Episodic Memory Trajectories

    PubMed Central

    Persson, Ninni; Lavebratt, Catharina; Sundström, Anna; Fischer, Håkan

    2016-01-01

    We investigated whether a physiological marker of cardiovascular health, pulse pressure (PP), and age magnified the effect of the functional COMT Val158Met (rs4680) polymorphism on 15-years cognitive trajectories [episodic memory (EM), visuospatial ability, and semantic memory] using data from 1585 non-demented adults from the Betula study. A multiple-group latent growth curve model was specified to gauge individual differences in change, and average trends therein. The allelic variants showed negligible differences across the cognitive markers in average trends. The older portion of the sample selectively age-magnified the effects of Val158Met on EM changes, resulting in greater decline in Val compared to homozygote Met carriers. This effect was attenuated by statistical control for PP. Further, PP moderated the effects of COMT on 15-years EM trajectories, resulting in greater decline in Val carriers, even after accounting for the confounding effects of sex, education, cardiovascular diseases (diabetes, stroke, and hypertension), and chronological age, controlled for practice gains. The effect was still present after excluding individuals with a history of cardiovascular diseases. The effects of cognitive change were not moderated by any other covariates. This report underscores the importance of addressing synergistic effects in normal cognitive aging, as the addition thereof may place healthy individuals at greater risk for memory decline. PMID:26973509

  16. 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

  17. 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.

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

    PubMed

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

    2014-11-01

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

  19. Complementary Role of Frontoparietal Activity and Cortical Pattern Similarity in Successful Episodic Memory Encoding

    PubMed Central

    Xue, Gui; Dong, Qi; Chen, Chuansheng; Lu, Zhong-Lin; Mumford, Jeanette A.; Poldrack, Russell A.

    2013-01-01

    One central goal in cognitive neuroscience of learning and memory is to characterize the neural processes that lead to long-lasting episodic memory. In addition to the stronger frontoparietal activity, greater category- or item-specific cortical representation during encoding, as measured by pattern similarity (PS), is also associated with better subsequent episodic memory. Nevertheless, it is unknown whether frontoparietal activity and cortical PS reflect distinct mechanisms. To address this issue, we reanalyzed previous data (Xue G, Dong Q, Chen C, Lu ZL, Mumford JA, Poldrack RA. 2010. Greater neural pattern similarity across repetitions is associated with better memory. Science. 330:97, Experiment 3) using a novel approach based on combined activation-based and information-based analyses. The results showed that across items, stronger frontoparietal activity was associated with greater PS in distributed brain regions, including those where the PS was predictive of better subsequent memory. Nevertheless, the item-specific PS was still associated with later episodic memory after controlling the effect of frontoparietal activity. Our results suggest that one possible mechanism of frontoparietal activity on episodic memory encoding is via enhancing PS, resulting in more unique and consistent input to the medial temporal lobe. In addition, they suggest that PS might index additional processes, such as pattern reinstatement as a result of study-phase retrieval, that contribute to episodic memory encoding. PMID:22645250

  20. Associative and Strategic Components of Episodic Memory: A Life-Span Dissociation

    ERIC Educational Resources Information Center

    Shing, Yee Lee; Werkle-Bergner, Markus; Li, Shu-Chen; Lindenberger, Ulman

    2008-01-01

    The authors investigated the strategic component (i.e., elaboration and organization of episodic features) and the associative component (i.e., binding processes) of episodic memory and their interactions in 4 age groups (10-12, 13-15, 20-25, and 70-75 years of age). On the basis of behavioral and neural evidence, the authors hypothesized that the…

  1. 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

  2. Prospective and Episodic Memory in Relation to Hippocampal Volume in Adults with Spina Bifida Myelomeningocele

    PubMed Central

    Treble-Barna, Amery; Juranek, Jenifer; Stuebing, Karla K.; Cirino, Paul T.; Dennis, Maureen; Fletcher, Jack M.

    2014-01-01

    The present study examined prospective and episodic memory in relation to age, functional independence, and hippocampal volume in younger to middle-aged adults with spina bifida myelomeningocele (SBM) and typically developing (TD) adults. Prospective and episodic memory, as well as hippocampal volume, were reduced in adults with SBM relative to TD adults. Neither memory performance nor hippocampal volume showed greater decrements in older adults. Lower hippocampal volume was associated with reduced prospective memory in adults with SBM, and this relation was specific to the hippocampus and not to a contrast structure, the amygdala. Prospective memory mediated the relation between hippocampal volume and functional independence in adults with SBM. The results add to emerging evidence for reduced memory function in adults with SBM, and provide quantitative evidence for compromised hippocampal macrostructure as a neural correlate of reduced memory in this population. PMID:25068670

  3. Distinct neural mechanisms underlie the success, precision, and vividness of episodic memory.

    PubMed

    Richter, Franziska R; Cooper, Rose A; Bays, Paul M; Simons, Jon S

    2016-10-25

    A network of brain regions have been linked with episodic memory retrieval, but limited progress has been made in identifying the contributions of distinct parts of the network. Here, we utilized continuous measures of retrieval to dissociate three components of episodic memory: retrieval success, precision, and vividness. In the fMRI scanner, participants encoded objects that varied continuously on three features: color, orientation, and location. Participants' memory was tested by having them recreate the appearance of the object features using a continuous dial, and continuous vividness judgments were recorded. Retrieval success, precision, and vividness were dissociable both behaviorally and neurally: successful versus unsuccessful retrieval was associated with hippocampal activity, retrieval precision scaled with activity in the angular gyrus, and vividness judgments tracked activity in the precuneus. The ability to dissociate these components of episodic memory reveals the benefit afforded by measuring memory on a continuous scale, allowing functional parcellation of the retrieval network.

  4. Stress administered prior to encoding impairs neutral but enhances emotional long-term episodic memories.

    PubMed

    Payne, Jessica D; Jackson, Eric D; Hoscheidt, Siobhan; Ryan, Lee; Jacobs, W Jake; Nadel, Lynn

    2007-12-01

    Stressful events frequently comprise both neutral and emotionally arousing information, yet the impact of stress on emotional and neutral events is still not fully understood. The hippocampus and frontal cortex have dense concentrations of receptors for stress hormones, such as cortisol, which at high levels can impair performance on hippocampally dependent memory tasks. Yet, the same stress hormones can facilitate memory for emotional information, which involves interactions between the hippocampus and amygdala. Here, we induced psychosocial stress prior to encoding and examined its long-term effects on memory for emotional and neutral episodes. The stress manipulation disrupted long-term memory for a neutral episode, but facilitated long-term memory for an equivalent emotional episode compared with a control condition. The stress manipulation also increased salivary cortisol, catecholamines as indicated by the presence of alpha-amylase, heart rate, and subjectively reported stress. Stressed subjects reported more false memories than nonstressed control subjects, and these false memories correlated positively with cortisol levels, providing evidence for a relationship between stress and false memory formation. Our results demonstrate that stress, when administered prior to encoding, produces different patterns of long-term remembering for neutral and emotional episodes. These differences likely emerge from differential actions of stress hormones on memory-relevant regions of the brain.

  5. From hippocampus to whole-brain: The role of integrative processing in episodic memory retrieval.

    PubMed

    Geib, Benjamin R; Stanley, Matthew L; Dennis, Nancy A; Woldorff, Marty G; Cabeza, Roberto

    2017-04-01

    Multivariate functional connectivity analyses of neuroimaging data have revealed the importance of complex, distributed interactions between disparate yet interdependent brain regions. Recent work has shown that topological properties of functional brain networks are associated with individual and group differences in cognitive performance, including in episodic memory. After constructing functional whole-brain networks derived from an event-related fMRI study of memory retrieval, we examined differences in functional brain network architecture between forgotten and remembered words. This study yielded three main findings. First, graph theory analyses showed that successfully remembering compared to forgetting was associated with significant changes in the connectivity profile of the left hippocampus and a corresponding increase in efficient communication with the rest of the brain. Second, bivariate functional connectivity analyses indicated stronger interactions between the left hippocampus and a retrieval assembly for remembered versus forgotten items. This assembly included the left precuneus, left caudate, bilateral supramarginal gyrus, and the bilateral dorsolateral superior frontal gyrus. Integrative properties of the retrieval assembly were greater for remembered than forgotten items. Third, whole-brain modularity analyses revealed that successful memory retrieval was marginally significantly associated with a less segregated modular architecture in the network. The magnitude of the decreases in modularity between remembered and forgotten conditions was related to memory performance. These findings indicate that increases in integrative properties at the nodal, retrieval assembly, and whole-brain topological levels facilitate memory retrieval, while also underscoring the potential of multivariate brain connectivity approaches for providing valuable new insights into the neural bases of memory processes. Hum Brain Mapp 38:2242-2259, 2017. © 2017 Wiley

  6. Effects of handedness & saccadic bilateral eye movements on the specificity of past autobiographical memory & episodic future thinking.

    PubMed

    Parker, Andrew; Parkin, Adam; Dagnall, Neil

    2017-03-25

    The present research investigated the effects of personal handedness and saccadic eye movements on the specificity of past autobiographical memory and episodic future thinking. Handedness and saccadic eye movements have been hypothesised to share a common functional basis in that both influence cognition through hemispheric interaction. The technique used to elicit autobiographical memory and episodic future thought involved a cued sentence completion procedure that allowed for the production of memories spanning the highly specific to the very general. Experiment 1 found that mixed-handed (vs. right handed) individuals generated more specific past autobiographical memories, but equivalent numbers of specific future predictions. Experiment 2 demonstrated that following 30s of bilateral (horizontal) saccades, more specific cognitions about both the past and future were generated. These findings extend previous research by showing that more distinct and episodic-like information pertaining to the self can be elicited by either mixed-handedness or eye movements. The results are discussed in relation to hemispheric interaction and top-down influences in the control of memory retrieval.

  7. Computational dissection of human episodic memory reveals mental process-specific genetic profiles.

    PubMed

    Luksys, Gediminas; Fastenrath, Matthias; Coynel, David; Freytag, Virginie; Gschwind, Leo; Heck, Angela; Jessen, Frank; Maier, Wolfgang; Milnik, Annette; Riedel-Heller, Steffi G; Scherer, Martin; Spalek, Klara; Vogler, Christian; Wagner, Michael; Wolfsgruber, Steffen; Papassotiropoulos, Andreas; de Quervain, Dominique J-F

    2015-09-01

    Episodic memory performance is the result of distinct mental processes, such as learning, memory maintenance, and emotional modulation of memory strength. Such processes can be effectively dissociated using computational models. Here we performed gene set enrichment analyses of model parameters estimated from the episodic memory performance of 1,765 healthy young adults. We report robust and replicated associations of the amine compound SLC (solute-carrier) transporters gene set with the learning rate, of the collagen formation and transmembrane receptor protein tyrosine kinase activity gene sets with the modulation of memory strength by negative emotional arousal, and of the L1 cell adhesion molecule (L1CAM) interactions gene set with the repetition-based memory improvement. Furthermore, in a large functional MRI sample of 795 subjects we found that the association between L1CAM interactions and memory maintenance revealed large clusters of differences in brain activity in frontal cortical areas. Our findings provide converging evidence that distinct genetic profiles underlie specific mental processes of human episodic memory. They also provide empirical support to previous theoretical and neurobiological studies linking specific neuromodulators to the learning rate and linking neural cell adhesion molecules to memory maintenance. Furthermore, our study suggests additional memory-related genetic pathways, which may contribute to a better understanding of the neurobiology of human memory.

  8. Computational dissection of human episodic memory reveals mental process-specific genetic profiles

    PubMed Central

    Luksys, Gediminas; Fastenrath, Matthias; Coynel, David; Freytag, Virginie; Gschwind, Leo; Heck, Angela; Jessen, Frank; Maier, Wolfgang; Milnik, Annette; Riedel-Heller, Steffi G.; Scherer, Martin; Spalek, Klara; Vogler, Christian; Wagner, Michael; Wolfsgruber, Steffen; Papassotiropoulos, Andreas; de Quervain, Dominique J.-F.

    2015-01-01

    Episodic memory performance is the result of distinct mental processes, such as learning, memory maintenance, and emotional modulation of memory strength. Such processes can be effectively dissociated using computational models. Here we performed gene set enrichment analyses of model parameters estimated from the episodic memory performance of 1,765 healthy young adults. We report robust and replicated associations of the amine compound SLC (solute-carrier) transporters gene set with the learning rate, of the collagen formation and transmembrane receptor protein tyrosine kinase activity gene sets with the modulation of memory strength by negative emotional arousal, and of the L1 cell adhesion molecule (L1CAM) interactions gene set with the repetition-based memory improvement. Furthermore, in a large functional MRI sample of 795 subjects we found that the association between L1CAM interactions and memory maintenance revealed large clusters of differences in brain activity in frontal cortical areas. Our findings provide converging evidence that distinct genetic profiles underlie specific mental processes of human episodic memory. They also provide empirical support to previous theoretical and neurobiological studies linking specific neuromodulators to the learning rate and linking neural cell adhesion molecules to memory maintenance. Furthermore, our study suggests additional memory-related genetic pathways, which may contribute to a better understanding of the neurobiology of human memory. PMID:26261317

  9. Retrieval from Episodic Memory: Neural Mechanisms of Interference Resolution

    ERIC Educational Resources Information Center

    Wimber, Maria; Rutschmann, Roland Marcus; Greenlee, Mark W.; Bauml, Karl-Heinz

    2009-01-01

    Selectively retrieving a target memory among related memories requires some degree of inhibitory control over interfering and competing memories, a process assumed to be supported by inhibitory mechanisms. Evidence from behavioral studies suggests that such inhibitory control can lead to subsequent forgetting of the interfering information, a…

  10. A Time and Place for Everything: Developmental Differences in the Building Blocks of Episodic Memory

    ERIC Educational Resources Information Center

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

    2016-01-01

    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…

  11. Two Rooms, Two Representations? Episodic-Like Memory in Toddlers and Preschoolers

    ERIC Educational Resources Information Center

    Newcombe, Nora S.; Balcomb, Frances; Ferrara, Katrina; Hansen, Melissa; Koski, Jessica

    2014-01-01

    Episodic memory involves binding together what-where-when associations. In three experiments, we tested the development of memory for such contextual associations in a naturalistic setting. Children searched for toys in two rooms with two different experimenters; each room contained two identical sets of four containers, but arranged differently.…

  12. The Relationship between Theory of Mind and Episodic Memory: Evidence for the Development of Autonoetic Consciousness.

    ERIC Educational Resources Information Center

    Naito, Mika

    2003-01-01

    Links between theory of mind and episodic memory involving autonoetic consciousness were investigated in Japanese 4- to 6-year-olds. After age was controlled for, most theory of mind abilities showed no interrelations. Own and others' belief understandings on deceptive appearance tasks were solely related to source memory. Results suggest that…

  13. The Effects of Spatial Contextual Familiarity on Remembered Scenes, Episodic Memories, and Imagined Future Events

    ERIC Educational Resources Information Center

    Robin, Jessica; Moscovitch, Morris

    2014-01-01

    Several recent studies have explored the effect of contextual familiarity on remembered and imagined events. The aim of this study was to examine the extent of this effect by comparing the effect of cuing spatial memories, episodic memories, and imagined future events with spatial contextual cues of varying levels of familiarity. We used…

  14. A Simple Neural Network Model of the Hippocampus Suggesting Its Pathfinding Role in Episodic Memory Retrieval

    ERIC Educational Resources Information Center

    Samsonovich, Alexei V.; Ascoli, Giorgio A.

    2005-01-01

    The goal of this work is to extend the theoretical understanding of the relationship between hippocampal spatial and memory functions to the level of neurophysiological mechanisms underlying spatial navigation and episodic memory retrieval. The proposed unifying theory describes both phenomena within a unique framework, as based on one and the…

  15. Why Am I Remembering This Now? Predicting the Occurrence of Involuntary (Spontaneous) Episodic Memories

    ERIC Educational Resources Information Center

    Berntsen, Dorthe; Staugaard, Soren Rislov; Sorensen, Louise Maria Torp

    2013-01-01

    Involuntary episodic memories are memories of events that come to mind spontaneously, that is, with no preceding retrieval attempts. They are common in daily life and observed in a range of clinical disorders in the form of negative, intrusive recollections or flashbacks. However, little is known about their underlying mechanisms. Here we report a…

  16. Resting-state fMRI evidence for early episodic memory consolidation: effects of age.

    PubMed

    Kukolja, Juraj; Göreci, D Yasemin; Onur, Özgür A; Riedl, Valentin; Fink, Gereon R

    2016-09-01

    Aging-related episodic memory decline is often attributed to insufficient encoding of new information, although the underlying neural processes remain elusive. We here tested the hypothesis that impaired memory consolidation contributes to aging-related memory decline. To this end, we used resting state functional magnetic resonance imaging in healthy young and older adults and investigated neural network connectivity underlying episodic memory consolidation and the effects of aging thereon. During postencoding rest, connectivity increased in subregions of temporobasal and temporo-occipital networks but decreased in a precuneal network. These connectivity changes predicted subsequent memory performance thereby constituting functional correlates of early memory consolidation. Furthermore, these consolidation-related regional connectivity changes partially overlapped with encoding-related neural activity changes, suggesting a close relationship between encoding- and consolidation-related activity. Older when compared to young participants failed to increase connectivity in the right lingual gyrus as part of an extended default mode network during consolidation, thereby providing a functional correlate for spatial contextual memory deficits. In conclusion, results are consistent with previous reports of persistent activity in regions mediating memory encoding as a core mechanism underlying episodic memory consolidation. Our data extend previous findings suggesting that aging-related memory decline results from a reduction of consolidation processes.

  17. 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

  18. The multifold relationship between memory and decision making: an individual-differences study.

    PubMed

    Del Missier, Fabio; Mäntylä, Timo; Hansson, Patrik; Bruine de Bruin, Wändi; Parker, Andrew M; Nilsson, Lars-Göran

    2013-09-01

    Several judgment and decision-making tasks are assumed to involve memory functions, but significant knowledge gaps on the memory processes underlying these tasks remain. In a study on 568 adults between 25 and 80 years of age, hypotheses were tested on the specific relationships between individual differences in working memory, episodic memory, and semantic memory, respectively, and 6 main components of decision-making competence. In line with the hypotheses, working memory was positively related with the more cognitively demanding tasks (Resistance to Framing, Applying Decision Rules, and Under/Overconfidence), whereas episodic memory was positively associated with a more experience-based judgment task (Recognizing Social Norms). Furthermore, semantic memory was positively related with 2 more knowledge-based decision-making tasks (Consistency in Risk Perception and Resistance to Sunk Costs). Finally, the age-related decline observed in some of the decision-making tasks was (partially or totally) mediated by the age-related decline in working memory or episodic memory. These findings are discussed in relation to the functional roles fulfilled by different memory processes in judgment and decision-making tasks.

  19. Self-Serving Episodic Memory Biases: Findings in the Repressive Coping Style

    PubMed Central

    Alston, Lauren L.; Kratchmer, Carissa; Jeznach, Anna; Bartlett, Nathan T.; Davidson, Patrick S. R.; Fujiwara, Esther

    2013-01-01

    Individuals with a repressive coping style self-report low anxiety, but show high defensiveness and high physiological arousal. Repressors have impoverished negative autobiographical memories and are better able to suppress memory for negatively valenced and self-related laboratory materials when asked to do so. Research on spontaneous forgetting of negative information in repressors suggests that they show significant forgetting of negative items, but only after a delay. Unknown is whether increased forgetting after a delay is potentiated by self-relevance. Here we asked in three experiments whether repressors would show reduced episodic memories for negative self-relevant information when tested immediately versus after a 2-day delay. We predicted that repressors would show an exaggerated reduction in recall of negative self-relevant memories after a delay, at least without anew priming of this information. We tested a total of 300 participants (experiment 1: N = 95, experiment 2: N = 106; experiment 3: N = 99) of four types: repressors, high-anxious (HA), low-anxious, and defensive HA individuals. Participants judged positive and negative adjectives with regard to self-descriptiveness, serving as incidental encoding. Surprise free-recall was conducted immediately after encoding (experiment 1), after a 2-day delay (experiment 2), or after a 2-day delay following priming via a lexical decision task (experiment 3). In experiment 1, repressors showed a bias against negative self-relevant words in immediate recall. Such a bias was neither observed in delayed recall without priming nor in delayed recall with priming. Thus, counter to our hypothesis, negative information that was initially judged as self-relevant was not forgotten at a higher rate after a delay in repressors. We suggest that repressors may reinterpret initially negative information in a more positive light after a delay, and therefore no longer experience the need to bias their recall after

  20. Episodic, but not semantic, autobiographical memory is reduced in amnestic mild cognitive impairment

    PubMed Central

    Murphy, Kelly J.; Troyer, Angela K.; Levine, Brian; Moscovitch, Morris

    2008-01-01

    Amnestic mild cognitive impairment (aMCI) is characterized by decline in anterograde memory as measured by the ability to learn and remember new information. We investigated whether retrograde memory for autobiographical information was affected by aMCI. Eighteen control (age 66–84 years) and 17 aMCI (age 66–84 years) participants described a personal event from each of five periods across the lifespan. These events were transcribed and scored according to procedures that separate episodic (specific happenings) from semantic (general knowledge) elements of autobiographical memory. Although both groups generated protocols of similar length, the composition of autobiographical recall differentiated the groups. The aMCI group protocols were characterized by reduced episodic and increased semantic information relative to the control group. Both groups showed a similar pattern of recall across time periods, with no evidence that the aMCI group had more difficulty recalling recent, rather than remote, life events. These results indicate that episodic and semantic autobiographical memories are differentially affected by the early brain changes associated with aMCI. Reduced autobiographical episodic memories in aMCI may be the result of medial-temporal-lobe dysfunction, consistent with multiple trace theory, or alternatively, could be related to dysfunction of a wider related network of neocortical structures. In contrast, the preservation of autobiographical semantic memories in aMCI suggests neural systems, such as lateral temporal cortex, that support these memories, may remain relatively intact. PMID:18675285

  1. Property content guides children's memory for social learning episodes.

    PubMed

    Riggs, Anne E; Kalish, Charles W; Alibali, Martha W

    2014-05-01

    How do children's interpretations of the generality of learning episodes affect what they encode? In the present studies, we investigated the hypothesis that children encode distinct aspects of learning episodes containing generalizable and non-generalizable properties. Two studies with preschool (N=50) and young school-aged children (N=49) reveal that their encoding is contingent on the generalizability of the property they are learning. Children remembered generalizable properties (e.g., morphological or normative properties) more than non-generalizable properties (e.g., historical events or preferences). Conversely, they remembered category exemplars associated with non-generalizable properties more than category exemplars associated with generalizable properties. The findings highlight the utility of remembering distinct aspects of social learning episodes for children's future generalization.

  2. Hippocampal Contributions to the Large-Scale Episodic Memory Network Predict Vivid Visual Memories.

    PubMed

    Geib, Benjamin R; Stanley, Matthew L; Wing, Erik A; Laurienti, Paul J; Cabeza, Roberto

    2017-01-01

    A common approach in memory research is to isolate the function(s) of individual brain regions, such as the hippocampus, without addressing how those regions interact with the larger network. To investigate the properties of the hippocampus embedded within large-scale networks, we used functional magnetic resonance imaging and graph theory to characterize complex hippocampal interactions during the active retrieval of vivid versus dim visual memories. The study yielded 4 main findings. First, the right hippocampus displayed greater communication efficiency with the network (shorter path length) and became a more convergent structure for information integration (higher centrality measures) for vivid than dim memories. Second, vivid minus dim differences in our graph theory measures of interest were greater in magnitude for the right hippocampus than for any other region in the 90-region network. Moreover, the right hippocampus significantly reorganized its set of direct connections from dim to vivid memory retrieval. Finally, beyond the hippocampus, communication throughout the whole-brain network was more efficient (shorter global path length) for vivid than dim memories. In sum, our findings illustrate how multivariate network analyses can be used to investigate the roles of specific regions within the large-scale network, while also accounting for global network changes.

  3. High field structural MRI reveals specific episodic memory correlates in the subfields of the hippocampus.

    PubMed

    Travis, S G; Huang, Y; Fujiwara, E; Radomski, A; Olsen, F; Carter, R; Seres, P; Malykhin, N V

    2014-01-01

    The involvement of the hippocampus (HC) in episodic memory is well accepted; however it is unclear how each subfield within the HC contributes to memory function. Recent magnetic resonance imaging (MRI) studies suggest differential involvement of hippocampal subfields and subregions in episodic memory. However, most structural MRI studies have examined the HC subfields within a single subregion of the HC and used specialised experimental memory paradigms. The purpose of the present study was to determine the association between volumes of HC subfields throughout the entire HC structure and performance on standard neuropsychological memory tests in a young, healthy population. We recruited 34 healthy participants under the age of 50. MRI data was acquired with a fast spin echo (FSE) sequence yielding a 0.52×0.68×1.0 mm(3) native resolution. The HC subfields - the cornu ammonis 1-3 (CA), dentate gyrus (DG), and subiculum (SUB) - were segmented manually within three hippocampal subregions using a previously defined protocol. Participants were administered the Wechsler Memory Scale, 4th edition (WMS-IV) to assess performance in episodic memory using verbal (Logical Memory, LM) and visual (Designs, DE; visual-spatial memory, DE-Spatial; visual-content memory, DE-Content) memory subtests. Working memory subtests (Spatial Addition, SA; and Symbol Span, SSP) were included as well. Working memory was not associated with any HC volumes. Volumes of the DG were correlated with verbal memory (LM) and visual-spatial memory (DE-Spatial). Posterior CA volumes correlated with both visual-spatial and visual-object memory (DE-Spatial, DE-Content). In general, anterior subregion volumes (HC head) correlated with verbal memory, while some anterior and many posterior HC subregion volumes (body and tail) correlated with visual memory scores (DE-Spatial, DE-Content). In addition, while verbal memory showed left-lateralized associations with HC volumes, visual memory was associated with

  4. 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

  5. Episodic memory encoding interferes with reward learning and decreases striatal prediction errors.

    PubMed

    Wimmer, G Elliott; Braun, Erin Kendall; Daw, Nathaniel D; Shohamy, Daphna

    2014-11-05

    Learning is essential for adaptive decision making. The striatum and its dopaminergic inputs are known to support incremental reward-based learning, while the hippocampus is known to support encoding of single events (episodic memory). Although traditionally studied separately, in even simple experiences, these two types of learning are likely to co-occur and may interact. Here we sought to understand the nature of this interaction by examining how incremental reward learning is related to concurrent episodic memory encoding. During the experiment, human participants made choices between two options (colored squares), each associated with a drifting probability of reward, with the goal of earning as much money as possible. Incidental, trial-unique object pictures, unrelated to the choice, were overlaid on each option. The next day, participants were given a surprise memory test for these pictures. We found that better episodic memory was related to a decreased influence of recent reward experience on choice, both within and across participants. fMRI analyses further revealed that during learning the canonical striatal reward prediction error signal was significantly weaker when episodic memory was stronger. This decrease in reward prediction error signals in the striatum was associated with enhanced functional connectivity between the hippocampus and striatum at the time of choice. Our results suggest a mechanism by which memory encoding may compete for striatal processing and provide insight into how interactions between different forms of learning guide reward-based decision making.

  6. Theta and High-Frequency Activity Mark Spontaneous Recall of Episodic Memories

    PubMed Central

    Burke, John F.; Sharan, Ashwini D.; Sperling, Michael R.; Ramayya, Ashwin G.; Evans, James J.; Healey, M. Karl; Beck, Erin N.; Davis, Kathryn A.; Lucas, Timothy H.

    2014-01-01

    Humans possess the remarkable ability to search their memory, allowing specific past episodes to be re-experienced spontaneously. Here, we administered a free recall test to 114 neurosurgical patients and used intracranial theta and high-frequency activity (HFA) to identify the spatiotemporal pattern of neural activity underlying spontaneous episodic retrieval. We found that retrieval evolved in three electrophysiological stages composed of: (1) early theta oscillations in the right temporal cortex, (2) increased HFA in the left hemisphere including the medial temporal lobe (MTL), left inferior frontal gyrus, as well as the ventrolateral temporal cortex, and (3) motor/language activation during vocalization of the retrieved item. Of these responses, increased HFA in the left MTL predicted recall performance. These results suggest that spontaneous recall of verbal episodic memories involves a spatiotemporal pattern of spectral changes across the brain; however, high-frequency activity in the left MTL represents a final common pathway of episodic retrieval. PMID:25143616

  7. Naringin and Rutin Alleviates Episodic Memory Deficits in Two Differentially Challenged Object Recognition Tasks

    PubMed Central

    Ramalingayya, Grandhi Venkata; Nampoothiri, Madhavan; Nayak, Pawan G.; Kishore, Anoop; Shenoy, Rekha R.; Mallikarjuna Rao, Chamallamudi; Nandakumar, Krishnadas

    2016-01-01

    Background: Cognitive decline or dementia is a debilitating problem of neurological disorders such as Alzheimer's and Parkinson's disease, including special conditions like chemobrain. Dietary flavonoids proved to be efficacious in delaying the incidence of neurodegenerative diseases. Two such flavonoids, naringin (NAR) and rutin (RUT) were reported to have neuroprotective potential with beneficial effects on spatial and emotional memories in particular. However, the efficacy of these flavonoids is poorly understood on episodic memory, which comprises an important form of autobiographical memory. Objective: This study objective is to evaluate NAR and RUT to reverse time-delay-induced long-term and scopolamine-induced short-term episodic memory deficits in Wistar rats. Materials and Methods: We have evaluated both short-term and long-term episodic memory forms using novel object recognition task. Open field paradigm was used to assess locomotor activity for any confounding influence on memory assessment. Donepezil was used as positive control and was effective in both models at 1 mg/kg, i.p. Results: Animals treated with NAR and RUT at 50 and 100 mg/kg, p.o. spent significantly more time exploring novel object compared to familiar one, whereas control animals spent almost equal time with both objects in choice trial. NAR and RUT dose-dependently increased recognition and discriminative indices in time-induced long-term as well as scopolamine-induced short-term episodic memory deficit models without interfering with the locomotor activity. Conclusion: We conclude that, NAR and RUT averted both short- and long-term episodic memory deficits in Wistar rats, which may be potential interventions for neurodegenerative diseases as well as chemobrain condition. SUMMARY Incidence of Alzheimer's disease is increasing globally and the current therapy is only symptomatic. Curative treatment is a major lacuna. NAR and RUT are natural flavonoids proven for their pleiotropic

  8. Sleep, Memory, and Aging: The Link Between Slow-Wave Sleep and Episodic Memory Changes from Younger to Older Adults

    PubMed Central

    Scullin, Michael K.

    2012-01-01

    In younger adults, recently learned episodic memories are reactivated and consolidated during slow-wave sleep (SWS). Interestingly, SWS declines across the lifespan but little research has examined whether sleep-dependent memory consolidation occurs in older adults. In the present study, younger adults and healthy older adults encoded word pairs in the morning or evening and then returned following a sleep or no-sleep interval. Sleep stage scoring was obtained using a home sleep-stage monitoring system. In the younger adult group, there was a positive correlation between word retention and amount of SWS. In contrast, the older adults demonstrated no significant positive correlations, but one significant negative correlation, between memory and SWS. These findings suggest that the link between episodic memory and SWS that is typically observed in younger adults may be weakened or otherwise changed in the healthy elderly. PMID:22708533

  9. Using semantic memory to boost 'episodic' recall in a case of developmental amnesia.

    PubMed

    Brandt, Karen R; Gardiner, John M; Vargha-Khadem, Faraneh; Baddeley, Alan D; Mishkin, Mortimer

    2006-07-17

    We report two experiments that investigated factors that might boost 'episodic' recall for Jon, a developmental amnesic whose episodic memory is gravely impaired but whose semantic memory seems relatively normal. Experiment 1 showed that Jon's recall improved following a semantic study task compared with a non-semantic study task, as well as following four repeated study trials compared with only one. Experiment 2 additionally revealed that Jon's recall improved after acting compared with reading action phrases at study, but only if the phrases were well integrated semantically. The results provide some support for the hypothesis that Jon's 'episodic' recall depends on the extent to which he is able to retrieve events using semantic memory.

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

    PubMed

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

    2014-10-01

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

  11. The benefits of staying active in old age: physical activity counteracts the negative influence of PICALM, BIN1, and CLU risk alleles on episodic memory functioning.

    PubMed

    Ferencz, Beata; Laukka, Erika J; Welmer, Anna-Karin; Kalpouzos, Grégoria; Angleman, Sara; Keller, Lina; Graff, Caroline; Lövdén, Martin; Bäckman, Lars

    2014-06-01

    PICALM, BIN1, CLU, and APOE are top candidate genes for Alzheimer's disease, and they influence episodic memory performance in old age. Physical activity, however, has been shown to protect against age-related decline and counteract genetic influences on cognition. The aims of this study were to assess whether (a) a genetic risk constellation of PICALM, BIN1, and CLU polymorphisms influences cognitive performance in old age; and (b) if physical activity moderates this effect. Data from the SNAC-K population-based study were used, including 2,480 individuals (age range = 60 to 100 years) free of dementia at baseline and at 3- to 6-year follow-ups. Tasks assessing episodic memory, perceptual speed, knowledge, and verbal fluency were administered. Physical activity was measured using self-reports. Individuals who had engaged in frequent health- or fitness-enhancing activities within the past year were compared with those who were inactive. Genetic risk scores were computed based on an integration of risk alleles for PICALM (rs3851179 G allele, rs541458 T allele), BIN1 (rs744373 G allele), and CLU (rs11136000 T allele). High genetic risk was associated with reduced episodic memory performance, controlling for age, education, vascular risk factors, chronic diseases, activities of daily living, and APOE gene status. Critically, physical activity attenuated the effects of genetic risk on episodic memory. Our findings suggest that participants with high genetic risk who maintain a physically active lifestyle show selective benefits in episodic memory performance.

  12. Creativity and Memory: Effects of an Episodic-Specificity Induction on Divergent Thinking.

    PubMed

    Madore, Kevin P; Addis, Donna Rose; Schacter, Daniel L

    2015-09-01

    People produce more episodic details when imagining future events and solving means-end problems after receiving an episodic-specificity induction-brief training in recollecting details of a recent event-than after receiving a control induction not focused on episodic retrieval. Here we show for the first time that an episodic-specificity induction also enhances divergent creative thinking. In Experiment 1, participants exhibited a selective boost on a divergent-thinking task (generating unusual uses of common objects) after a specificity induction compared with a control induction; by contrast, performance following the two inductions was similar on an object association task thought to involve little divergent thinking. In Experiment 2, we replicated the specificity-induction effect on divergent thinking using a different control induction, and also found that participants performed similarly on a convergent-thinking task following the two inductions. These experiments provide novel evidence that episodic memory is involved in divergent creative thinking.

  13. Creativity and Memory: Effects of an Episodic Specificity Induction on Divergent Thinking

    PubMed Central

    Madore, Kevin P.; Addis, Donna Rose; Schacter, Daniel L.

    2015-01-01

    After receiving an episodic specificity induction - brief training in recollecting details of a recent event - people produce more episodic details when imagining future events and solving means-end problems than after receiving a control induction not focused on episodic retrieval. Here we show for the first time that an episodic specificity induction also enhances divergent creative thinking. In Experiment 1, participants exhibited a selective boost on a divergent thinking task that involves generating unusual uses of common objects after a specificity induction compared with a control induction; by contrast, performance was similar on an object association task thought to involve little divergent thinking. In Experiment 2, we replicated the specificity induction effect on divergent thinking using a different control induction, and also found that participants performed similarly on a convergent thinking task following both inductions. These experiments provide novel evidence that episodic memory is involved in divergent creative thinking. PMID:26205963

  14. Pre-Service Teachers' Episodic Memories of Classroom Management

    ERIC Educational Resources Information Center

    Balli, Sandra J.

    2011-01-01

    This study focused on past excellent teachers' classroom management strategies from the perspective of 148 pre-service teachers. The purpose of the study was to examine how pre-service teachers' memories reflect classroom management models that are typically taught in teacher education coursework prior to their study of those models, as well as to…

  15. A Negative Effect of Repetition in Episodic Memory

    ERIC Educational Resources Information Center

    Peterson, Daniel J.; Mulligan, Neil W.

    2012-01-01

    One of the foundational principles of human memory is that repetition (i.e., being presented with a stimulus multiple times) improves recall. In the current study a group of participants who studied a list of cue-target pairs twice recalled fewer targets than a group who studied the pairs only once, a negative repetition effect. Such a…

  16. Usefulness of an Integrated Analysis of Different Memory Tasks to Predict the Progression from Mild Cognitive Impairment to Alzheimer's Disease: The Episodic Memory Score (EMS).

    PubMed

    Marra, Camillo; Gainotti, Guido; Fadda, Lucia; Perri, Roberta; Lacidogna, Giordano; Scaricamazza, Eugenia; Piccininni, Chiara; Quaranta, Davide

    2016-01-01

    Taking into the account both the severity and the consistency of performances obtained on memory tests by patients with amnestic mild cognitive impairment (aMCI) could improve the power to predict their progression to Alzheimer's disease. For this purpose, we constructed the Episodic Memory Score (EMS), which is obtained by subdividing in tertiles performances obtained at baseline in verbal (RAVLT) and visual episodic memory (Rey-Osterrieth Figure-delayed recall) and giving a score ranging from 1 (worst result) to 3 (best result) to results falling within each tertile. The EMS was computed for each patient by summing the tertile score obtained on each memory task, so that the total score ranged from 4 (worst performance) to 12 (best performance). The aMCI sample consisted of 198 subjects who completed the two-year follow-up, at the end of which 55 subjects had converted to dementia. The mean EMS score obtained by aMCI converters was significantly lower than that of aMCI-stable patients. In detecting conversion to dementia, the comparison between EMS and individual memory scores obtained at baseline was made by computing ROC curves, and estimating the respective area under the curve (AUC). The EMS had a larger AUC than the individual memory scores. At baseline aMCI converters performed worse than non-converters not only on memory tasks, but also on executive functions tasks. However, in a multiple variables logistic regression analysis in which all scores showing statistically significant differences between aMCI-converters and aMCI-stable were entered, the EMS was the only reliable predictor of progression from aMCI to dementia.

  17. 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.

  18. Episodic sequence memory is supported by a theta-gamma phase code

    PubMed Central

    Heusser, Andrew C.; Poeppel, David; Ezzyat, Youssef; Davachi, Lila

    2016-01-01

    The meaning we derive from our experiences is not a simple static extraction of the elements, but is largely based on the order in which those elements occur. Models propose that sequence encoding is supported by interactions between high and low frequency oscillations, such that elements within an experience are represented by neural cell assemblies firing at higher frequencies (i.e. gamma) and sequential order is coded by the specific timing of firing with respect to a lower frequency oscillation (i.e. theta). During episodic sequence memory formation in humans, we provide evidence that items in different sequence positions exhibit relatively greater gamma power along distinct phases of a theta oscillation. Furthermore, this segregation is related to successful temporal order memory. These results provide compelling evidence that memory for order, a core component of an episodic memory, capitalizes on the ubiquitous physiological mechanism of theta-gamma phase-amplitude coupling. PMID:27571010

  19. The episodicity of verbal reports of personally significant autobiographical memories: vividness correlates with narrative text quality more than with detailedness or memory specificity.

    PubMed

    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.

  20. Effects of eating rate on satiety: A role for episodic memory?

    PubMed Central

    Ferriday, Danielle; Bosworth, Matthew L.; Lai, Samantha; Godinot, Nicolas; Martin, Nathalie; Martin, Ashley A.; Rogers, Peter J.; Brunstrom, Jeffrey M.

    2015-01-01

    Eating slowly is associated with a lower body mass index. However, the underlying mechanism is poorly understood. Here, our objective was to determine whether eating a meal at a slow rate improves episodic memory for the meal and promotes satiety. Participants (N = 40) consumed a 400 ml portion of tomato soup at either a fast (1.97 ml/s) or a slow (0.50 ml/s) rate. Appetite ratings were elicited at baseline and at the end of the meal (satiation). Satiety was assessed using; i) an ad libitum biscuit ‘taste test’ (3 h after the meal) and ii) appetite ratings (collected 2 h after the meal and after the ad libitum snack). Finally, to evaluate episodic memory for the meal, participants self-served the volume of soup that they believed they had consumed earlier (portion size memory) and completed a rating of memory ‘vividness’. Participants who consumed the soup slowly reported a greater increase in fullness, both at the end of the meal and during the inter-meal interval. However, we found little effect of eating rate on subsequent ad libitum snack intake. Importantly, after 3 h, participants who ate the soup slowly remembered eating a larger portion. These findings show that eating slowly promotes self-reported satiation and satiety. For the first time, they also suggest that eating rate influences portion size memory. However, eating slowly did not affect ratings of memory vividness and we found little evidence for a relationship between episodic memory and satiety. Therefore, we are unable to conclude that episodic memory mediates effects of eating rate on satiety. PMID:26143189

  1. Effects of eating rate on satiety: A role for episodic memory?

    PubMed

    Ferriday, Danielle; Bosworth, Matthew L; Lai, Samantha; Godinot, Nicolas; Martin, Nathalie; Martin, Ashley A; Rogers, Peter J; Brunstrom, Jeffrey M

    2015-12-01

    Eating slowly is associated with a lower body mass index. However, the underlying mechanism is poorly understood. Here, our objective was to determine whether eating a meal at a slow rate improves episodic memory for the meal and promotes satiety. Participants (N=40) consumed a 400ml portion of tomato soup at either a fast (1.97ml/s) or a slow (0.50ml/s) rate. Appetite ratings were elicited at baseline and at the end of the meal (satiation). Satiety was assessed using; i) an ad libitum biscuit 'taste test' (3h after the meal) and ii) appetite ratings (collected 2h after the meal and after the ad libitum snack). Finally, to evaluate episodic memory for the meal, participants self-served the volume of soup that they believed they had consumed earlier (portion size memory) and completed a rating of memory 'vividness'. Participants who consumed the soup slowly reported a greater increase in fullness, both at the end of the meal and during the inter-meal interval. However, we found little effect of eating rate on subsequent ad libitum snack intake. Importantly, after 3h, participants who ate the soup slowly remembered eating a larger portion. These findings show that eating slowly promotes self-reported satiation and satiety. For the first time, they also suggest that eating rate influences portion size memory. However, eating slowly did not affect ratings of memory vividness and we found little evidence for a relationship between episodic memory and satiety. Therefore, we are unable to conclude that episodic memory mediates effects of eating rate on satiety.

  2. A simple neural network model of the hippocampus suggesting its pathfinding role in episodic memory retrieval.

    PubMed

    Samsonovich, Alexei V; Ascoli, Giorgio A

    2005-01-01

    The goal of this work is to extend the theoretical understanding of the relationship between hippocampal spatial and memory functions to the level of neurophysiological mechanisms underlying spatial navigation and episodic memory retrieval. The proposed unifying theory describes both phenomena within a unique framework, as based on one and the same pathfinding function of the hippocampus. We propose a mechanism of reconstruction of the context of experience involving a search for a nearly shortest path in the space of remembered contexts. To analyze this concept in detail, we define a simple connectionist model consistent with available rodent and human neurophysiological data. Numerical study of the model begins with the spatial domain as a simple analogy for more complex phenomena. It is demonstrated how a nearly shortest path is quickly found in a familiar environment. We prove numerically that associative learning during sharp waves can account for the necessary properties of hippocampal place cells. Computational study of the model is extended to other cognitive paradigms, with the main focus on episodic memory retrieval. We show that the ability to find a correct path may be vital for successful retrieval. The model robustly exhibits the pathfinding capacity within a wide range of several factors, including its memory load (up to 30,000 abstract contexts), the number of episodes that become associated with potential target contexts, and the level of dynamical noise. We offer several testable critical predictions in both spatial and memory domains to validate the theory. Our results suggest that (1) the pathfinding function of the hippocampus, in addition to its associative and memory indexing functions, may be vital for retrieval of certain episodic memories, and (2) the hippocampal spatial navigation function could be a precursor of its memory function.

  3. A simple neural network model of the hippocampus suggesting its pathfinding role in episodic memory retrieval

    PubMed Central

    Samsonovich, Alexei V.; Ascoli, Giorgio A.

    2005-01-01

    The goal of this work is to extend the theoretical understanding of the relationship between hippocampal spatial and memory functions to the level of neurophysiological mechanisms underlying spatial navigation and episodic memory retrieval. The proposed unifying theory describes both phenomena within a unique framework, as based on one and the same pathfinding function of the hippocampus. We propose a mechanism of reconstruction of the context of experience involving a search for a nearly shortest path in the space of remembered contexts. To analyze this concept in detail, we define a simple connectionist model consistent with available rodent and human neurophysiological data. Numerical study of the model begins with the spatial domain as a simple analogy for more complex phenomena. It is demonstrated how a nearly shortest path is quickly found in a familiar environment. We prove numerically that associative learning during sharp waves can account for the necessary properties of hippocampal place cells. Computational study of the model is extended to other cognitive paradigms, with the main focus on episodic memory retrieval. We show that the ability to find a correct path may be vital for successful retrieval. The model robustly exhibits the pathfinding capacity within a wide range of several factors, including its memory load (up to 30,000 abstract contexts), the number of episodes that become associated with potential target contexts, and the level of dynamical noise. We offer several testable critical predictions in both spatial and memory domains to validate the theory. Our results suggest that (1) the pathfinding function of the hippocampus, in addition to its associative and memory indexing functions, may be vital for retrieval of certain episodic memories, and (2) the hippocampal spatial navigation function could be a precursor of its memory function. PMID:15774943

  4. Self and social functions: individual autobiographical memory and collective narrative.

    PubMed

    Nelson, Katherine

    2003-03-01

    The personal functions of autobiographical memory build on the basic biological functions of memory common to most mammals that, however, do not have the kind of episodic memories that compose human autobiographical memory according to present theory. The thesis here is that personal autobiographical memory is functionally and structurally related to the use of cultural myths and social narratives, and that the relative emphasis put on the self in different cultural and social contexts influences the form and function of autobiographical memory and the need for developing a uniquely personal life narrative in those contexts. Historical and cross-cultural trends revealed in psychological and literary research are invoked to support this thesis.

  5. The Nature of Individual Differences in Working Memory Capacity: Active Maintenance in Primary Memory and Controlled Search from Secondary Memory

    ERIC Educational Resources Information Center

    Unsworth, Nash; Engle, Randall W.

    2007-01-01

    Studies examining individual differences in working memory capacity have suggested that individuals with low working memory capacities demonstrate impaired performance on a variety of attention and memory tasks compared with individuals with high working memory capacities. This working memory limitation can be conceived of as arising from 2…

  6. Does virtual reality have a future for the study of episodic memory in aging?

    PubMed

    Abichou, Kouloud; La Corte, Valentina; Piolino, Pascale

    2017-03-01

    Episodic memory is the memory of personally lived events located in time and space, it shapes our identity and allows us to project ourselves into the past and the future. This form of memory is vulnerable to the effects of age and its alteration, hindering the autonomy of the subjects, can predict the evolution towards neurodegenerative disorders. Hence, a better understanding of this type of memory is a priority in the field of public health. Actually, traditional neuropsychological tools are often decontextualized, using simplistic situations that did not require the mobilization of all the characteristics of episodic memory, thus they just offer a partial measure of this complex mnemonic capacity. Nowadays, the virtual reality (VR) is a tool allowing the immersion of subjects in simulations of real situations, rich in spatial and temporal naturalistic contexts. Due to its many characteristics, the VR allows to solve several limitations of the traditional tests. The purpose of this review is to expose studies that investigated episodic memory in normal and Alzheimer's disease using VR in order to address its relevance as a new tool in the future practice of neuropsychology of aging.

  7. Dopamine D2 receptor availability is linked to hippocampal–caudate functional connectivity and episodic memory

    PubMed Central

    Nyberg, Lars; Karalija, Nina; Salami, Alireza; Andersson, Micael; Wåhlin, Anders; Kaboovand, Neda; Köhncke, Ylva; Axelsson, Jan; Rieckmann, Anna; Papenberg, Goran; Garrett, Douglas D.; Riklund, Katrine; Lövdén, Martin; Bäckman, Lars

    2016-01-01

    D1 and D2 dopamine receptors (D1DRs and D2DRs) may contribute differently to various aspects of memory and cognition. The D1DR system has been linked to functions supported by the prefrontal cortex. By contrast, the role of the D2DR system is less clear, although it has been hypothesized that D2DRs make a specific contribution to hippocampus-based cognitive functions. Here we present results from 181 healthy adults between 64 and 68 y of age who underwent comprehensive assessment of episodic memory, working memory, and processing speed, along with MRI and D2DR assessment with [11C]raclopride and PET. Caudate D2DR availability was positively associated with episodic memory but not with working memory or speed. Whole-brain analyses further revealed a relation between hippocampal D2DR availability and episodic memory. Hippocampal and caudate D2DR availability were interrelated, and functional MRI-based resting-state functional connectivity between the ventral caudate and medial temporal cortex increased as a function of caudate D2DR availability. Collectively, these findings indicate that D2DRs make a specific contribution to hippocampus-based cognition by influencing striatal and hippocampal regions, and their interactions. PMID:27339132

  8. The influence of Markov decision process structure on the possible strategic use of working memory and episodic memory.

    PubMed

    Zilli, Eric A; Hasselmo, Michael E

    2008-07-23

    Researchers use a variety of behavioral tasks to analyze the effect of biological manipulations on memory function. This research will benefit from a systematic mathematical method for analyzing memory demands in behavioral tasks. In the framework of reinforcement learning theory, these tasks can be mathematically described as partially-observable Markov decision processes. While a wealth of evidence collected over the past 15 years relates the basal ganglia to the reinforcement learning framework, only recently has much attention been paid to including psychological concepts such as working memory or episodic memory in these models. This paper presents an analysis that provides a quantitative description of memory states sufficient for correct choices at specific decision points. Using information from the mathematical structure of the task descriptions, we derive measures that indicate whether working memory (for one or more cues) or episodic memory can provide strategically useful information to an agent. In particular, the analysis determines which observed states must be maintained in or retrieved from memory to perform these specific tasks. We demonstrate the analysis on three simplified tasks as well as eight more complex memory tasks drawn from the animal and human literature (two alternation tasks, two sequence disambiguation tasks, two non-matching tasks, the 2-back task, and the 1-2-AX task). The results of these analyses agree with results from quantitative simulations of the task reported in previous publications and provide simple indications of the memory demands of the tasks which can require far less computation than a full simulation of the task. This may provide a basis for a quantitative behavioral stoichiometry of memory tasks.

  9. 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.

  10. 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

  11. Protective Role of Educational Level on Episodic Memory Aging: An Event-Related Potential Study

    ERIC Educational Resources Information Center

    Angel, Lucie; Fay, Severine; Bouazzaoui, Badiaa; Baudouin, Alexia; Isingrini, Michel

    2010-01-01

    The aim of the present experiment was to investigate whether educational level could modulate the effect of aging on episodic memory and on the electrophysiological correlates of retrieval success. Participants were divided into four groups based on age (young vs. older) and educational level (high vs. low), with 14 participants in each group.…

  12. Interrelations between Subjective Health and Episodic Memory Change in Swedish and Canadian Samples of Older Adults

    ERIC Educational Resources Information Center

    Wahlin, Ake; Maitland, Scott B.; Backman, Lars; Dixon, Roger A.

    2003-01-01

    Recent research has documented associations between subjective health ratings and objective indicators of disease and death. Less is known about relations between subjective health ratings and level of cognitive performance in older adults. In this study, we explored whether subjective health ratings are related to episodic memory performance,…

  13. Generalization through the Recurrent Interaction of Episodic Memories: A Model of the Hippocampal System

    ERIC Educational Resources Information Center

    Kumaran, Dharshan; McClelland, James L.

    2012-01-01

    In this article, we present a perspective on the role of the hippocampal system in generalization, instantiated in a computational model called REMERGE (recurrency and episodic memory results in generalization). We expose a fundamental, but neglected, tension between prevailing computational theories that emphasize the function of the hippocampus…

  14. Integrating Incremental Learning and Episodic Memory Models of the Hippocampal Region

    ERIC Educational Resources Information Center

    Meeter, M.; Myers, C. E.; Gluck, M. A.

    2005-01-01

    By integrating previous computational models of corticohippocampal function, the authors develop and test a unified theory of the neural substrates of familiarity, recollection, and classical conditioning. This approach integrates models from 2 traditions of hippocampal modeling, those of episodic memory and incremental learning, by drawing on an…

  15. Do Different Tests of Episodic Memory Produce Consistent Results in Human Adults?

    ERIC Educational Resources Information Center

    Cheke, Lucy G.; Clayton, Nicola S.

    2013-01-01

    A number of different philosophical, theoretical, and empirical perspectives on episodic memory have led to the development of very different tests with which to assess it. Although these tests putatively assess the same psychological capacity, they have rarely been directly compared. Here, a sample of undergraduates was tested on three different…

  16. 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…

  17. 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…

  18. Binge drinking during adolescence and young adulthood is associated with deficits in verbal episodic memory.

    PubMed

    Carbia, Carina; Cadaveira, Fernando; Caamaño-Isorna, Francisco; Rodríguez-Holguín, Socorro; Corral, Montse

    2017-01-01

    Binge drinking (BD), a harmful pattern of alcohol consumption, is common during adolescence. Young adults with alcohol use disorders exhibit hippocampal alterations and episodic memory deficits. However, it is not known how these difficulties progress in community BD adolescents. Our objective was to analyze the relationship between BD trajectory and verbal episodic memory during the developmental period spanning from adolescence and to early adulthood. An initial sample of 155 male and female first-year university students with no other risk factors were followed over six years. Participants were classified as stable non-BDs, stable BDs and ex-BDs according to the third AUDIT item. At baseline, participants comprised 36 ♂/ 40 ♀ non-BDs (18.58 years), 40 ♂/ 39 ♀ BDs (18.87 years), and at the third follow-up, they comprised 8 ♂/ 8 ♀ stable non-BDs (25.49 years), 2 ♂/ 2 ♀ stable BDs (25.40) and 8 ♂/ 12 ♀ ex-BDs (24.97 years). Episodic memory was assessed four times with the Logical Memory subtest (WMS-III) and the Rey Auditory Verbal Learning Test (RAVLT). Generalized linear mixed models were applied. The results showed that, relative to non-BDs, stable BDs presented difficulties in immediate and delayed recall in the Logical Memory subtest. These difficulties remained stable over time. The short-term ex-BDs continued to display difficulties in immediate and delayed recall in the Logical Memory subtest, but long-term ex-BDs did not. The effects were not influenced by age of alcohol onset, frequency of cannabis use, tobacco use or psychopathological distress. In conclusion, BD during adolescence and young adulthood is associated with episodic memory deficits. Abandoning the BD pattern may lead to partial recovery. These findings are consistent with the vulnerability of the adolescent hippocampus to the neurotoxic effects of alcohol.

  19. A Prefrontal-Hippocampal Comparator for Goal-Directed Behavior: The Intentional Self and Episodic Memory

    PubMed Central

    Numan, Robert

    2015-01-01

    The hypothesis of this article is that the interactions between the prefrontal cortex and the hippocampus play a critical role in the modulation of goal-directed self-action and the strengthening of episodic memories. We describe various theories that model a comparator function for the hippocampus, and then elaborate the empirical evidence that supports these theories. One theory which describes a prefrontal-hippocampal comparator for voluntary action is emphasized. Action plans are essential for successful goal-directed behavior, and are elaborated by the prefrontal cortex. When an action plan is initiated, the prefrontal cortex transmits an efference copy (or corollary discharge) to the hippocampus where it is stored as a working memory for the action plan (which includes the expected outcomes of the action plan). The hippocampus then serves as a response intention-response outcome working memory comparator. Hippocampal comparator function is enabled by the hippocampal theta rhythm allowing the hippocampus to compare expected action outcomes to actual action outcomes. If the expected and actual outcomes match, the hippocampus transmits a signal to prefrontal cortex which strengthens or consolidates the action plan. If a mismatch occurs, the hippocampus transmits an error signal to the prefrontal cortex which facilitates a reformulation of the action plan, fostering behavioral flexibility and memory updating. The corollary discharge provides the self-referential component to the episodic memory, affording the personal and subjective experience of what behavior was carried out, when it was carried out, and in what context (where) it occurred. Such a perspective can be applied to episodic memory in humans, and episodic-like memory in non-human animal species. PMID:26635567

  20. A Prefrontal-Hippocampal Comparator for Goal-Directed Behavior: The Intentional Self and Episodic Memory.

    PubMed

    Numan, Robert

    2015-01-01

    The hypothesis of this article is that the interactions between the prefrontal cortex and the hippocampus play a critical role in the modulation of goal-directed self-action and the strengthening of episodic memories. We describe various theories that model a comparator function for the hippocampus, and then elaborate the empirical evidence that supports these theories. One theory which describes a prefrontal-hippocampal comparator for voluntary action is emphasized. Action plans are essential for successful goal-directed behavior, and are elaborated by the prefrontal cortex. When an action plan is initiated, the prefrontal cortex transmits an efference copy (or corollary discharge) to the hippocampus where it is stored as a working memory for the action plan (which includes the expected outcomes of the action plan). The hippocampus then serves as a response intention-response outcome working memory comparator. Hippocampal comparator function is enabled by the hippocampal theta rhythm allowing the hippocampus to compare expected action outcomes to actual action outcomes. If the expected and actual outcomes match, the hippocampus transmits a signal to prefrontal cortex which strengthens or consolidates the action plan. If a mismatch occurs, the hippocampus transmits an error signal to the prefrontal cortex which facilitates a reformulation of the action plan, fostering behavioral flexibility and memory updating. The corollary discharge provides the self-referential component to the episodic memory, affording the personal and subjective experience of what behavior was carried out, when it was carried out, and in what context (where) it occurred. Such a perspective can be applied to episodic memory in humans, and episodic-like memory in non-human animal species.

  1. Binge drinking during adolescence and young adulthood is associated with deficits in verbal episodic memory

    PubMed Central

    Cadaveira, Fernando; Caamaño-Isorna, Francisco; Rodríguez-Holguín, Socorro

    2017-01-01

    Binge drinking (BD), a harmful pattern of alcohol consumption, is common during adolescence. Young adults with alcohol use disorders exhibit hippocampal alterations and episodic memory deficits. However, it is not known how these difficulties progress in community BD adolescents. Our objective was to analyze the relationship between BD trajectory and verbal episodic memory during the developmental period spanning from adolescence and to early adulthood. An initial sample of 155 male and female first-year university students with no other risk factors were followed over six years. Participants were classified as stable non-BDs, stable BDs and ex-BDs according to the third AUDIT item. At baseline, participants comprised 36 ♂/ 40 ♀ non-BDs (18.58 years), 40 ♂/ 39 ♀ BDs (18.87 years), and at the third follow-up, they comprised 8 ♂/ 8 ♀ stable non-BDs (25.49 years), 2 ♂/ 2 ♀ stable BDs (25.40) and 8 ♂/ 12 ♀ ex-BDs (24.97 years). Episodic memory was assessed four times with the Logical Memory subtest (WMS-III) and the Rey Auditory Verbal Learning Test (RAVLT). Generalized linear mixed models were applied. The results showed that, relative to non-BDs, stable BDs presented difficulties in immediate and delayed recall in the Logical Memory subtest. These difficulties remained stable over time. The short-term ex-BDs continued to display difficulties in immediate and delayed recall in the Logical Memory subtest, but long-term ex-BDs did not. The effects were not influenced by age of alcohol onset, frequency of cannabis use, tobacco use or psychopathological distress. In conclusion, BD during adolescence and young adulthood is associated with episodic memory deficits. Abandoning the BD pattern may lead to partial recovery. These findings are consistent with the vulnerability of the adolescent hippocampus to the neurotoxic effects of alcohol. PMID:28152062

  2. Episodic memory in transient global amnesia: encoding, storage, or retrieval deficit?

    PubMed Central

    Eustache, F.; Desgranges, B.; Laville, P.; Guillery, B.; Lalevee, C.; Schaeffer, S.; de la Sayette, V.; Iglesias, S.; Baron, J.; Viader, F.

    1999-01-01

    OBJECTIVES—To assess episodic memory (especially anterograde amnesia) during the acute phase of transient global amnesia to differentiate an encoding, a storage, or a retrieval deficit.
METHODS—In three patients, whose amnestic episode fulfilled all current criteria for transient global amnesia, a neuropsychological protocol was administered which included a word learning task derived from the Grober and Buschke's procedure.
RESULTS—In one patient, the results suggested an encoding deficit, and in two others, a storage deficit.
CONCLUSIONS—The encoding/storage impairment concerning anterograde amnesia documented in our patients stands in clear contrast with the impairment in retrieval which must underly the retrograde amnesia that also characterises transient global amnesia. This dissociation in turn favours the idea of a functional independence among the cognitive mechanisms that subserve episodic memory.

 PMID:10071092

  3. Effects of cortisol on the laterality of the neural correlates of episodic memory.

    PubMed

    Alhaj, Hamid A; Massey, Anna E; McAllister-Williams, R Hamish

    2008-10-01

    Alterations in the laterality of cortical activity have been shown in depressive illnesses. One possible pathophysiological mechanism for this is an effect of corticosteroids. We have previously demonstrated that endogenous cortisol concentrations correlate with the asymmetry of cortical activity related to episodic memory in healthy subjects and depressed patients. To further-examine whether this is due to a causal effect of cortisol on the laterality of episodic memory, we studied the effect of exogenous administration of cortisol in healthy subjects. Twenty-three right-handed healthy male volunteers were tested in a double-blind cross-over study. Event-related potentials (ERPs) were recorded during an episodic memory task following a four-day course of 160mg/day cortisol or placebo. Low-resolution brain electromagnetic tomography (LORETA) was used to identify brain regions involved in the neurocognitive task. Cortisol levels were measured in saliva samples. ERP and LORETA analysis following placebo demonstrated significant left parahippocampal activation associated with successful retrieval. Cortisol led to a decrease in the mean early frontal ERP voltage and an increase in the late right ERP voltage. LORETA suggested this to be due to a significant increased late activation of the right superior frontal gyrus. There was no significant effect of cortisol on episodic memory performance. This study suggests that exogenous cortisol leads to more positive-going waveforms over the right than the left hemisphere, possibly due to increased monitoring of the products of retrieval. The results support the hypothesis of causal effects of cortisol on the laterality of cortical activity occurring during an episodic memory task.

  4. Development of episodic and autobiographical memory: The importance of remembering forgetting.

    PubMed

    Bauer, Patricia J

    2015-12-01

    Some memories of the events of our lives have a long shelf-life-they remain accessible to recollection even after long delays. Yet many other of our experiences are forgotten, sometimes very soon after they take place. In spite of the prevalence of forgetting, theories of the development of episodic and autobiographical memory largely ignore it as a potential source of variance in explanation of age-related variability in long-term recall. They focus instead on what may be viewed as positive developmental changes, that is, changes that result in improvements in the quality of memory representations that are formed. The purpose of this review is to highlight the role of forgetting as an important variable in understanding the development of episodic and autobiographical memory. Forgetting processes are implicated as a source of variability in long-term recall due to the protracted course of development of the neural substrate responsible for transformation of fleeting experiences into memory traces that can be integrated into long-term stores and retrieved at later points in time. It is logical to assume that while the substrate is developing, neural processing is relatively inefficient and ineffective, resulting in loss of information from memory (i.e., forgetting). For this reason, focus on developmental increases in the quality of representations of past events and experiences will tell only a part of the story of how memory develops. A more complete account is afforded when we also consider changes in forgetting.

  5. Development of episodic and autobiographical memory: The importance of remembering forgetting

    PubMed Central

    Bauer, Patricia J.

    2015-01-01

    Some memories of the events of our lives have a long shelf-life—they remain accessible to recollection even after long delays. Yet many other of our experiences are forgotten, sometimes very soon after they take place. In spite of the prevalence of forgetting, theories of the development of episodic and autobiographical memory largely ignore it as a potential source of variance in explanation of age-related variability in long-term recall. They focus instead on what may be viewed as positive developmental changes, that is, changes that result in improvements in the quality of memory representations that are formed. The purpose of this review is to highlight the role of forgetting as an important variable in understanding the development of episodic and autobiographical memory. Forgetting processes are implicated as a source of variability in long-term recall due to the protracted course of development of the neural substrate responsible for transformation of fleeting experiences into memory traces that can be integrated into long-term stores and retrieved at later points in time. It is logical to assume that while the substrate is developing, neural processing is relatively inefficient and ineffective, resulting in loss of information from memory (i.e., forgetting). For this reason, focus on developmental increases in the quality of representations of past events and experiences will tell only a part of the story of how memory develops. A more complete account is afforded when we also consider changes in forgetting. PMID:26644633

  6. CE verbal episodic memory impairment in schizophrenia: a comparison with frontal lobe lesion patients.

    PubMed

    Christensen, Bruce K; Patrick, Regan E; Stuss, Donald T; Gillingham, Susan; Zipursky, Robert B

    2013-01-01

    Schizophrenia (SCZ)-related verbal memory impairment is hypothesized to be mediated, in part, by frontal lobe (FTL) dysfunction. However, little research has contrasted the performance of SCZ patients with that of patients exhibiting circumscribed frontal lesions. The current study compared verbal episodic memory in patients with SCZ and focal FTL lesions (left frontal, LF; right frontal, RF; and bi-frontal, BF) on a four-trial list learning task consisting of three lists of varying semantic organizational structure. Each dependent variable was examined at two levels: scores collapsed across all four trials and learning scores (i.e., trial 4-trial 1). Performance deficits were observed in each patient group across most dependent measures at both levels. Regarding patient group differences, SCZ patients outperformed LF/BF patients (i.e., either learning scores or scores collapsed across trial) on free recall, primacy, primary memory, secondary memory, and subjective organization, whereas they only outperformed RF patients on the semantically blocked list on recency and primary memory. Collectively, these results indicate that the pattern of memory performance is largely similar between patients with SCZ and those with RF lesions. These data support tentative arguments that verbal episodic memory deficits in SCZ may be mediated by frontal dysfunction in the right hemisphere.

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

    PubMed

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

    2010-01-01

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

  8. Distinct neural mechanisms underlie the success, precision, and vividness of episodic memory

    PubMed Central

    Richter, Franziska R; Cooper, Rose A; Bays, Paul M; Simons, Jon S

    2016-01-01

    A network of brain regions have been linked with episodic memory retrieval, but limited progress has been made in identifying the contributions of distinct parts of the network. Here, we utilized continuous measures of retrieval to dissociate three components of episodic memory: retrieval success, precision, and vividness. In the fMRI scanner, participants encoded objects that varied continuously on three features: color, orientation, and location. Participants’ memory was tested by having them recreate the appearance of the object features using a continuous dial, and continuous vividness judgments were recorded. Retrieval success, precision, and vividness were dissociable both behaviorally and neurally: successful versus unsuccessful retrieval was associated with hippocampal activity, retrieval precision scaled with activity in the angular gyrus, and vividness judgments tracked activity in the precuneus. The ability to dissociate these components of episodic memory reveals the benefit afforded by measuring memory on a continuous scale, allowing functional parcellation of the retrieval network. DOI: http://dx.doi.org/10.7554/eLife.18260.001 PMID:27776631

  9. Narrative organisation at encoding facilitated children's long-term episodic memory.

    PubMed

    Wang, Qi; Bui, Van-Kim; Song, Qingfang

    2015-01-01

    This study examined the effect of narrative organisation at encoding on long-term episodic memory in a sample of five- to seven-year-old children (N = 113). At an initial interview, children were asked to narrate a story from a picture book. Six months later, they were interviewed again and asked to recall the story and answer a series of direct questions about the story. Children who initially encoded more information in narrative and produced more complete, complex, cohesive and coherent narratives remembered the story in greater detail and accuracy following the six-month interval, independent of age and verbal skills. The relation between narrative organisation and memory was consistent across culture and gender. These findings provide new insight into the critical role of narrative in episodic memory.

  10. Episodic-like memory trace in awake replay of hippocampal place cell activity sequences.

    PubMed

    Takahashi, Susumu

    2015-10-20

    Episodic memory retrieval of events at a specific place and time is effective for future planning. Sequential reactivation of the hippocampal place cells along familiar paths while the animal pauses is well suited to such a memory retrieval process. It is, however, unknown whether this awake replay represents events occurring along the path. Using a subtask switching protocol in which the animal experienced three subtasks as 'what' information in a maze, I here show that the replay represents a trial type, consisting of path and subtask, in terms of neuronal firing timings and rates. The actual trial type to be rewarded could only be reliably predicted from replays that occurred at the decision point. This trial-type representation implies that not only 'where and when' but also 'what' information is contained in the replay. This result supports the view that awake replay is an episodic-like memory retrieval process.

  11. The Effects of Acute Stress on Episodic Memory: A Meta-Analysis and Integrative Review.

    PubMed

    Shields, Grant S; Sazma, Matthew A; McCullough, Andrew M; Yonelinas, Andrew P

    2017-04-03

    A growing body of research has indicated that acute stress can critically impact memory. However, there are a number of inconsistencies in the literature, and important questions remain regarding the conditions under which stress effects emerge as well as basic questions about how stress impacts different phases of memory. In this meta-analysis, we examined 113 independent studies in humans with 6,216 participants that explored effects of stress on encoding, postencoding, retrieval, or postreactivation phases of episodic memory. The results indicated that when stress occurred prior to or during encoding it impaired memory, unless both the delay between the stressor and encoding was very short and the study materials were directly related to the stressor, in which case stress improved encoding. In contrast, postencoding stress improved memory unless the stressor occurred in a different physical context than the study materials. When stress occurred just prior to or during retrieval, memory was impaired, and these effects were larger for emotionally valenced materials than neutral materials. Although stress consistently increased cortisol, the magnitude of the cortisol response was not related to the effects of stress on memory. Nonetheless, the effects of stress on memory were generally reduced in magnitude for women taking hormonal contraceptives. These analyses indicate that stress disrupts some episodic memory processes while enhancing others, and that the effects of stress are modulated by a number of critical factors. These results provide important constraints on current theories of stress and memory, and point to new questions for future research. (PsycINFO Database Record

  12. Theta oscillations at encoding mediate the context-dependent nature of human episodic memory.

    PubMed

    Staudigl, Tobias; Hanslmayr, Simon

    2013-06-17

    Human episodic memory is highly context dependent. Therefore, retrieval benefits when a memory is recalled in the same context compared to a different context. This implies that items and contexts are bound together during encoding, such that the reinstatement of the initial context at test improves retrieval. Animal studies suggest that theta oscillations and theta-to-gamma cross-frequency coupling modulate such item-context binding, but direct evidence from humans is scarce. We investigated this issue by manipulating the overlap of contextual features between encoding and retrieval. Participants studied words superimposed on movie clips and were later tested by presenting the word with either the same or a different movie. The results show that memory performance and the oscillatory correlates of memory formation crucially depend on the overlap of the context between encoding and test. When the context matched, high theta power during encoding was related to successful recognition, whereas the opposite pattern emerged in the context-mismatch condition. In addition, cross-frequency coupling analysis revealed a context-dependent theta-to-gamma memory effect specifically in the left hippocampus. These results reveal for the first time that context-dependent episodic memory effects are mediated by theta oscillatory activity.

  13. 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

  14. Assessing the role of memory in preschoolers' performance on episodic foresight tasks.

    PubMed

    Atance, Cristina M; Sommerville, Jessica A

    2014-01-01

    A total of 48 preschoolers (ages 3, 4, and 5) received four tasks modelled after prior work designed to assess the development of "episodic foresight". For each task, children encountered a problem in one room and, after a brief delay, were given the opportunity in a second room to select an item to solve the problem. Importantly, after selecting an item, children were queried about their memory for the problem. Age-related changes were found both in children's ability to select the correct item and their ability to remember the problem. However, when we controlled for children's memory for the problem, there were no longer significant age-related changes on the item choice measure. These findings suggest that age-related changes in children's performance on these tasks are driven by improvements in children's memory versus improvements in children's future-oriented thinking or "foresight" per se. Our results have important implications for how best to structure tasks to measure children's episodic foresight, and also for the relative role of memory in this task and in episodic foresight more broadly.

  15. Pauses During Autobiographical Discourse Reflect Episodic Memory Processes in Early Alzheimer's Disease.

    PubMed

    Pistono, Aurélie; Jucla, Mélanie; Barbeau, Emmanuel J; Saint-Aubert, Laure; Lemesle, Béatrice; Calvet, Benjamin; Köpke, Barbara; Puel, Michèle; Pariente, Jérémie

    2016-01-01

    There is a large body of research on discourse production in Alzheimer's disease (AD). Some studies have focused on pause production, revealing that patients make extensive use of pauses during speech. This has been attributed to lexical retrieval difficulties, but pausing may also reflect other forms of cognitive impairment as it increases with cognitive load. The aim of the present study was to analyze autobiographical discourse impairment in AD from a broad perspective, looking at pausing behavior (frequency, duration, and location). Our first objective was to characterize discourse changes in mild cognitive impairment (MCI) due to AD. Our second objective was to determine the cognitive and neuroanatomical correlates of these changes. Fifteen patients with MCI due to AD and 15 matched cognitively normal controls underwent an ecological episodic memory task, a full neuropsychological assessment, and a 3D T1-weighted MRI scans. Autobiographical discourse collected from the ecological episodic memory task was recorded, transcribed, and analyzed, focusing on pausing. Intergroup comparisons showed that although patients did not produce more pauses than controls overall, they did make more between-utterance pauses. The number of these specific pauses was positively correlated with patients' episodic memory performance. Furthermore, neuroimaging analysis showed that, in the patient group, their use was negatively correlated with frontopolar area (BA 10) grey matter density. This region may therefore play an important role in the planning of autobiographical discourse production. These findings demonstrate that pauses in early AD may reflect a compensatory mechanism for improving mental time travel and memory retrieval.

  16. 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.

  17. Modafinil administration improves working memory in methamphetamine-dependent individuals who demonstrate baseline impairment.

    PubMed

    Kalechstein, Ari D; De La Garza, Richard; Newton, Thomas F

    2010-01-01

    Modafinil improves working memory in healthy subjects and individuals diagnosed with schizophrenia and Attention Deficit/Hyperactivity Disorder, though the effects of modafinil have not been evaluated on working memory in methamphetamine-dependent subjects. This double-blind, placebo-controlled study evaluated whether a daily dose of 400 mg of modafinil, administered over three consecutive days, would enhance performance on a measure of working memory relative to test performance at baseline and following 3 days of placebo administration in 11 methamphetamine addicted, nontreatment-seeking volunteers. The results revealed that participants demonstrating relatively poor performance on the third day of a 3-day washout period (ie, at baseline), showed significant improvement on measures of working memory, but not on measures of episodic memory or information processing speed. In contrast, for participants demonstrating relatively high performance at baseline, modafinil administration did not affect test scores. The findings provide an initial indication that modafinil can reverse methamphetamine-associated impairments in working memory.

  18. Sex differences in HIV effects on visual memory among substance-dependent individuals.

    PubMed

    Keutmann, Michael K; Gonzalez, Raul; Maki, Pauline M; Rubin, Leah H; Vassileva, Jasmin; Martin, Eileen M

    2016-11-13

    HIV's effects on episodic memory have not been compared systematically between male and female substance-dependent individuals. We administered the Brief Visuospatial Memory Test-Revised (BVMT-R) to 280 substance-dependent HIV+ and HIV- men and women. Groups were comparable on demographic, substance use, and comorbid characteristics. There were no significant main effects of sex or HIV serostatus on BVMT-R performance, but HIV+ women performed significantly more poorly on delayed recall. This effect was most prominent among cocaine-dependent HIV+ women. Our findings are consistent with recent speculation that memory impairment may be more common among HIV+ women, particularly those with a history of cocaine dependence.

  19. 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.

  20. 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.

  1. 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

  2. Developmental Changes in Memory-Related Linguistic Skills and Their Relationship to Episodic Recall in Children

    PubMed Central

    Uehara, Izumi

    2015-01-01

    This longitudinal study of nine children examined two issues concerning infantile amnesia: the time at which memories for events experienced before the age of 3–4 years disappear from consciousness and whether this timing of memory loss is related to the development of specific aspects of episodic and autobiographical memory. This study followed children from infancy to early childhood and examined the central role of three verbal–cognitive milestones related to autobiographical memory: the age at which children begin to report autobiographical memories using the past tense (Milestone 1); the age at which they begin to verbally acknowledge past events (Milestone 2); and the age at which they begin to spontaneously use memory-related verbs (Milestone 3). As expected, memories of events that occurred before 3–4 years of age were affected by infantile amnesia. Achievement of these milestones followed almost the same developmental progression: Milestone 1 (1 year; 10 months (1;10) to 3 years; 4 months (3;4)) was followed by Milestones 2 (3;1 to 4;0) and 3 (3;5 to 4;4). Milestone 2 was typically related to the onset of infantile amnesia, whereas Milestone 1 occurred during the period for which the children became amnesic as they aged. These data suggest that linguistic meta-cognitive awareness of personal memory is the key feature in infantile amnesia. PMID:26331479

  3. Insights from neuropsychology: pinpointing the role of the posterior parietal cortex in episodic and working memory.

    PubMed

    Berryhill, Marian E

    2012-01-01

    The role of posterior parietal cortex (PPC) in various forms of memory is a current topic of interest in the broader field of cognitive neuroscience. This large cortical region has been linked with a wide range of mnemonic functions affecting each stage of memory processing: encoding, maintenance, and retrieval. Yet, the precise role of the PPC in memory remains mysterious and controversial. Progress in understanding PPC function will require researchers to incorporate findings in a convergent manner from multiple experimental techniques rather than emphasizing a particular type of data. To facilitate this process, here, we review findings from the human neuropsychological research and examine the consequences to memory following PPC damage. Recent patient-based research findings have investigated two typically disconnected fields: working memory (WM) and episodic memory. The findings from patient participants with unilateral and bilateral PPC lesions performing diverse experimental paradigms are summarized. These findings are then related to findings from other techniques including neurostimulation (TMS and tDCS) and the influential and more abundant functional neuroimaging literature. We then review the strengths and weaknesses of hypotheses proposed to account for PPC function in these forms of memory. Finally, we address what missing evidence is needed to clarify the role(s) of the PPC in memory.

  4. Insights from neuropsychology: pinpointing the role of the posterior parietal cortex in episodic and working memory

    PubMed Central

    Berryhill, Marian E.

    2012-01-01

    The role of posterior parietal cortex (PPC) in various forms of memory is a current topic of interest in the broader field of cognitive neuroscience. This large cortical region has been linked with a wide range of mnemonic functions affecting each stage of memory processing: encoding, maintenance, and retrieval. Yet, the precise role of the PPC in memory remains mysterious and controversial. Progress in understanding PPC function will require researchers to incorporate findings in a convergent manner from multiple experimental techniques rather than emphasizing a particular type of data. To facilitate this process, here, we review findings from the human neuropsychological research and examine the consequences to memory following PPC damage. Recent patient-based research findings have investigated two typically disconnected fields: working memory (WM) and episodic memory. The findings from patient participants with unilateral and bilateral PPC lesions performing diverse experimental paradigms are summarized. These findings are then related to findings from other techniques including neurostimulation (TMS and tDCS) and the influential and more abundant functional neuroimaging literature. We then review the strengths and weaknesses of hypotheses proposed to account for PPC function in these forms of memory. Finally, we address what missing evidence is needed to clarify the role(s) of the PPC in memory. PMID:22701406

  5. Prospective memory, personality, and individual differences.

    PubMed

    Uttl, Bob; White, Carmela A; Wong Gonzalez, Daniela; McDouall, Joanna; Leonard, Carrie A

    2013-01-01

    A number of studies investigating the relationship between personality and prospective memory (ProM) have appeared during the last decade. However, a review of these studies reveals little consistency in their findings and conclusions. To clarify the relationship between ProM and personality, we conducted two studies: a meta-analysis of prior research investigating the relationships between ProM and personality, and a study with 378 participants examining the relationships between ProM, personality, verbal intelligence, and retrospective memory. Our review of prior research revealed great variability in the measures used to assess ProM, and in the methodological quality of prior research; these two factors may partially explain inconsistent findings in the literature. Overall, the meta-analysis revealed very weak correlations (rs ranging from 0.09 to 0.10) between ProM and three of the Big Five factors: Openness, Conscientiousness, and Agreeableness. Our experimental study showed that ProM performance was related to individual differences such as verbal intelligence as well as to personality factors and that the relationship between ProM and personality factors depends on the ProM subdomain. In combination, the two studies suggest that ProM performance is relatively weakly related to personality factors and more strongly related to individual differences in cognitive factors.

  6. Deconstructing the effect of self-directed study on episodic memory.

    PubMed

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

    2014-11-01

    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 isolated 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 a participant was 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 they highlight the need to consider the range of cognitive control processes involved in and influenced by self-directed study.

  7. A neural framework for organization and flexible utilization of episodic memory in cumulatively learning baby humanoids.

    PubMed

    Mohan, Vishwanathan; Sandini, Giulio; Morasso, Pietro

    2014-12-01

    Cumulatively developing robots offer a unique opportunity to reenact the constant interplay between neural mechanisms related to learning, memory, prospection, and abstraction from the perspective of an integrated system that acts, learns, remembers, reasons, and makes mistakes. Situated within such interplay lie some of the computationally elusive and fundamental aspects of cognitive behavior: the ability to recall and flexibly exploit diverse experiences of one's past in the context of the present to realize goals, simulate the future, and keep learning further. This article is an adventurous exploration in this direction using a simple engaging scenario of how the humanoid iCub learns to construct the tallest possible stack given an arbitrary set of objects to play with. The learning takes place cumulatively, with the robot interacting with different objects (some previously experienced, some novel) in an open-ended fashion. Since the solution itself depends on what objects are available in the "now," multiple episodes of past experiences have to be remembered and creatively integrated in the context of the present to be successful. Starting from zero, where the robot knows nothing, we explore the computational basis of organization episodic memory in a cumulatively learning humanoid and address (1) how relevant past experiences can be reconstructed based on the present context, (2) how multiple stored episodic memories compete to survive in the neural space and not be forgotten, (3) how remembered past experiences can be combined with explorative actions to learn something new, and (4) how multiple remembered experiences can be recombined to generate novel behaviors (without exploration). Through the resulting behaviors of the robot as it builds, breaks, learns, and remembers, we emphasize that mechanisms of episodic memory are fundamental design features necessary to enable the survival of autonomous robots in a real world where neither everything can be known

  8. Autobiographical memory and episodic future thinking after moderate to severe traumatic brain injury.

    PubMed

    Rasmussen, Katrine W; Berntsen, Dorthe

    2014-03-01

    Converging evidence suggests that autobiographical memory and episodic future thinking share a common neurocognitive basis. Although previous research has shown that traumatic brain injury (TBI) can impair the ability to remember the personal past, episodic future thinking has not previously been systematically examined within this population. In this study, we examined the ability to remember events in the personal past and the ability to imagine possible events in the personal future in a sample of moderate-to-severe TBI patients. We present data on nine patients and nine healthy controls, who were asked to report a series of events that had happened to them in the past and a series of events that might happen to them in the future. Transcriptions were scored according to a reliable system for categorizing internal (episodic) and external (semantic) information. For each event described, participants also completed two modified Autobiographical Memory Questionnaire items to assess self-reported phenomenal qualities associated with remembering and imagining. In addition, TBI patients underwent neuropsychological assessment. Results revealed that TBI patients recalled/imagined proportionally fewer episodic event-specific details for both past and future events compared to healthy controls (η²(p) = 0.78). In contrast, there were no group differences in ratings of phenomenal characteristics. These results are discussed in relation to theories suggesting that remembering and imagining the future are the expression of the same underlying neurocognitive system.

  9. Acute stress and episodic memory retrieval: neurobiological mechanisms and behavioral consequences.

    PubMed

    Gagnon, Stephanie A; Wagner, Anthony D

    2016-04-01

    Episodic retrieval allows people to access memories from the past to guide current thoughts and decisions. In many real-world situations, retrieval occurs under conditions of acute stress, either elicited by the retrieval task or driven by other, unrelated concerns. Memory under such conditions may be hindered, as acute stress initiates a cascade of neuromodulatory changes that can impair episodic retrieval. Here, we review emerging evidence showing that dissociable stress systems interact over time, influencing neural function. In addition to the adverse effects of stress on hippocampal-dependent retrieval, we consider how stress biases attention and prefrontal cortical function, which could further affect controlled retrieval processes. Finally, we consider recent data indicating that stress at retrieval increases activity in a network of brain regions that enable reflexive, rapid responding to upcoming threats, while transiently taking offline regions supporting flexible, goal-directed thinking. Given the ubiquity of episodic memory retrieval in everyday life, it is critical to understand the theoretical and applied implications of acute stress. The present review highlights the progress that has been made, along with important open questions.

  10. Did the popsicle melt? Preschoolers' performance in an episodic-like memory task.

    PubMed

    Martin-Ordas, Gema; Atance, Cristina M; Caza, Julian

    2017-02-16

    Episodic memory has been tested in non-human animals using depletion paradigms that assess recollection for the "what", "where" and "when" (i.e., how long ago). This paradigm has not been used with human children, yet doing so would provide another means to explore their episodic memory development. Using a depletion paradigm, preschool-aged children were presented in two trials with a preferred food that was only edible after a short interval and a less-preferred food that was edible after the short and long intervals. Younger (mean = 40 months) and older (mean = 65 months) children tended to choose their preferred food after the short intervals, but did not switch to selecting their less-preferred food after the long intervals. Importantly, their choices did not differ with age. Although older children better remembered "what", "where", and "what is where" than did younger children, neither age group successfully estimated "how long ago" an event occurred. Finally, both age groups spontaneously recalled information about Trial 1. We also analysed the relation between the different measures used in the study but no clear patterns emerged. Results are discussed with respect to the cognitive mechanisms necessary to succeed in depletion paradigms and the measurement of episodic memory more broadly.

  11. Terminal decline of episodic memory and perceptual speed in a biracial population.

    PubMed

    Wilson, Robert S; Rajan, Kumar B; Barnes, Lisa L; Jansen, Willemijn; Amofa, Priscilla; Weuve, Jennifer; Evans, Denis A

    2017-03-23

    We compared trajectories of terminal cognitive decline in older Black (n = 3372) and White (n = 1756) persons from a defined population who completed tests of episodic memory and perceptual speed at 3-year intervals for up to 18 years. During a mean of 9.9 years of observation, 1608 Black persons and 902 White persons died. Preterminal decline of episodic memory did not differ by race. Terminal episodic memory decline began earlier in Black persons (mean of 4.3 years before death) than in White persons (mean = 3.9 years) and progressed more slowly. By contrast, terminal decline of perceptual speed began earlier in White persons (mean = 5.0 years) than in Black persons (mean = 4.5 years). Rate of perceptual speed decline was more rapid in White persons than in Black persons in both the preterminal and terminal periods. The results indicate that terminal cognitive decline occurs in Black persons but suggest that the rate of cognitive decline during the terminal period is less rapid in Black persons than in White persons.

  12. Traumatic stress is linked to a deficit in associative episodic memory.

    PubMed

    Guez, Jonathan; Naveh-Benjamin, Moshe; Yankovsky, Yan; Cohen, Jonathan; Shiber, Asher; Shalev, Hadar

    2011-06-01

    Individuals with posttraumatic stress disorder (PTSD) are haunted by persistent memories of the trauma, but ironically are impaired in memories of daily life. The current set of 4 experiments compared new learning and memory of emotionally neutral content in 2 groups of patients and aged- and education-matched controls: 20 patients diagnosed with chronic posttraumatic stress disorder (C-PTSD) and 20 patients diagnosed with acute stress disorder (ASD). In all experiments, participants studied a list of stimuli pairs (words or pictures) and were then tested for their memory of the items, or for the association between items in each pair. Results indicated that both types of patients showed associative memory impairment compared to a control group, although their item memory performance was relatively intact. Potential mechanisms underlying such associative memory deficits in posttraumatic patients are discussed.

  13. Keeping track of time: evidence for episodic-like memory in great apes.

    PubMed

    Martin-Ordas, Gema; Haun, Daniel; Colmenares, Fernando; Call, Josep

    2010-03-01

    Episodic memory, as defined by Tulving, can be described in terms of behavioural elements (what, where and when information) but it is also accompanied by an awareness of one's past (chronesthesia) and a subjective conscious experience (autonoetic awareness). Recent experiments have shown that corvids and rodents recall the where, what and when of an event. This capability has been called episodic-like memory because it only fulfils the behavioural criteria for episodic memory. We tested seven chimpanzees, three orangutans and two bonobos of various ages by adapting two paradigms, originally developed by Clayton and colleagues to test scrub jays. In Experiment 1, subjects were fed preferred but perishable food (frozen juice) and less preferred but non-perishable food (grape). After the food items were hidden, subjects could choose one of them either after 5 min or 1 h. The frozen juice was still available after 5 min but melted after 1 h and became unobtainable. Apes chose the frozen juice significantly more after 5 min and the grape after 1 h. In Experiment 2, subjects faced two baiting events happening at different times, yet they formed an integrated memory for the location and time of the baiting event for particular food items. We also included a memory task that required no temporal encoding. Our results showed that apes remember in an integrated fashion what, where and when (i.e., how long ago) an event happened; that is, apes distinguished between different events in which the same food items were hidden in different places at different times. The temporal control of their choices was not dependent on the familiarity of the platforms where the food was hidden. Chimpanzees' and bonobos' performance in the temporal encoding task was age-dependent, following an inverted U-shaped distribution. The age had no effect on the performance of the subjects in the task that required no temporal encoding.

  14. 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

  15. 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.

  16. 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,…

  17. 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.

  18. 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

  19. 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.

  20. How Semantic and Episodic Memory Contribute to Autobiographical Memory. Commentary on Burt

    ERIC Educational Resources Information Center

    Tendolkar, Indira

    2008-01-01

    In his article, Chris Burt focuses on the relationship between time and autobiographical memory. The question Burt puts forward is whether temporal markers in reports on autobiographic memories reflect specific temporal information or result from rather complex cognitive processing of time-relevant knowledge. The aspect of time is inherent to the…

  1. The Sensory Nature of Episodic Memory: Sensory Priming Effects Due to Memory Trace Activation

    ERIC Educational Resources Information Center

    Brunel, Lionel; Labeye, Elodie; Lesourd, Mathieu; Versace, Remy

    2009-01-01

    The aim of this study was to provide evidence that memory and perceptual processing are underpinned by the same mechanisms. Specifically, the authors conducted 3 experiments that emphasized the sensory aspect of memory traces. They examined their predictions with a short-term priming paradigm based on 2 distinct phases: a learning phase consisting…

  2. Delineating the Effect of Semantic Congruency on Episodic Memory: The Role of Integration and Relatedness

    PubMed Central

    Bein, Oded; Livneh, Neta; Reggev, Niv; Gilead, Michael; Goshen-Gottstein, Yonatan; Maril, Anat

    2015-01-01

    A fundamental challenge in the study of learning and memory is to understand the role of existing knowledge in the encoding and retrieval of new episodic information. The importance of prior knowledge in memory is demonstrated in the congruency effect—the robust finding wherein participants display better memory for items that are compatible, rather than incompatible, with their pre-existing semantic knowledge. Despite its robustness, the mechanism underlying this effect is not well understood. In four studies, we provide evidence that demonstrates the privileged explanatory power of the elaboration-integration account over alternative hypotheses. Furthermore, we question the implicit assumption that the congruency effect pertains to the truthfulness/sensibility of a subject-predicate proposition, and show that congruency is a function of semantic relatedness between item and context words. PMID:25695759

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

    PubMed

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

    2017-04-01

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

  4. Temporal contexts: filling the gap between episodic memory and associative learning.

    PubMed

    Matute, Helena; Lipp, Ottmar V; Vadillo, Miguel A; Humphreys, Michael S

    2011-11-01

    People can create temporal contexts, or episodes, and stimuli that belong to the same context can later be used to retrieve the memory of other events that occurred at the same time. This can occur in the absence of direct contingency and contiguity between the events, which poses a challenge to associative theories of learning and memory. Because this is a learning and memory problem, we propose an integrated approach. Theories of temporal contexts developed in the memory tradition provide interesting predictions that we test using the methods of associative learning to assess their generality and applicability to different settings and dependent variables. In 4 experiments, the integration of these 2 areas allows us to show that (a) participants spontaneously create temporal contexts in the absence of explicit instructions; (b) cues can be used to retrieve an old temporal context and the information associated with other cues that were trained in that context; and (c) the memory of a retrieved temporal context can be updated with information from the current situation that does not fit well with the retrieved memory, thereby helping participants to best adapt their behavior to the future changes of the environment.

  5. Pauses During Autobiographical Discourse Reflect Episodic Memory Processes in Early Alzheimer’s Disease

    PubMed Central

    Pistono, Aurélie; Jucla, Mélanie; Barbeau, Emmanuel J.; Saint-Aubert, Laure; Lemesle, Béatrice; Calvet, Benjamin; Köpke, Barbara; Puel, Michèle; Pariente, Jérémie

    2015-01-01

    There is a large body of research on discourse production in Alzheimer’s disease (AD). Some studies have focused on pause production, revealing that patients make extensive use of pauses during speech. This has been attributed to lexical retrieval difficulties, but pausing may also reflect other forms of cognitive impairment as it increases with cognitive load. The aim of the present study was to analyze autobiographical discourse impairment in AD from a broad perspective, looking at pausing behavior (frequency, duration, and location). Our first objective was to characterize discourse changes in mild cognitive impairment (MCI) due to AD. Our second objective was to determine the cognitive and neuroanatomical correlates of these changes. Fifteen patients with MCI due to AD and 15 matched cognitively normal controls underwent an ecological episodic memory task, a full neuropsychological assessment, and a 3D T1-weighted MRI scans. Autobiographical discourse collected from the ecological episodic memory task was recorded, transcribed, and analyzed, focusing on pausing. Intergroup comparisons showed that although patients did not produce more pauses than controls overall, they did make more between-utterance pauses. The number of these specific pauses was positively correlated with patients’ episodic memory performance. Furthermore, neuroimaging analysis showed that, in the patient group, their use was negatively correlated with frontopolar area (BA 10) grey matter density. This region may therefore play an important role in the planning of autobiographical discourse production. These findings demonstrate that pauses in early AD may reflect a compensatory mechanism for improving mental time travel and memory retrieval. PMID:26757034

  6. Working Memory Capacity: An Individual Differences Approach.

    DTIC Science & Technology

    1988-02-11

    a % - AV ~ ~ 2 a . a’* - Working memory capacity -54- Experiment 5 Some researchers (e.g, Klapp , et al. (1983) and Brainerd and Kingma (1984, 1985...Psychological Review. 85,363-394. Klapp , S. T., Marshbum, E. A & Lester, P. T. (1983). Short term memory does not Involve the ’Worklng memory,* of

  7. 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.

  8. Segregating cognitive functions within hippocampal formation: a quantitative meta-analysis on spatial navigation and episodic memory.

    PubMed

    Kühn, Simone; Gallinat, Jürgen

    2014-04-01

    The most important cognitive domains where hippocampal formation is crucially involved are navigation and memory. Some evidence suggests that different hippocampal subregions mediate these domains. However, a quantitative meta-analysis on neuroimaging studies of spatial navigation versus memory is lacking. By means of activation likelihood estimation (ALE), we investigate concurrence of brain regions activated during spatial navigation encoding and retrieval as well as during episodic memory encoding and retrieval tasks in humans. During encoding in spatial navigation, activity was located in more posterior regions of the hippocampal formation, whereas episodic memory encoding was located in more anterior regions. Retrieval in spatial navigation was more strongly lateralized to the right compared to episodic memory retrieval. Within studies on spatial navigation retrieval, immediate recall was located more posterior and delayed recall more anterior. Overlap between concurrence of activation in spatial navigation and episodic memory was rather limited in comparison to uniquely involved regions. This argues in favor of two distinct networks, one for spatial navigation the other for episodic memory within the hippocampal formation.

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

    PubMed

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

    2010-05-01

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

  10. Functional heterogeneity in posterior parietal cortex across attention and episodic memory retrieval.

    PubMed

    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.

  11. Episodic-like memory trace in awake replay of hippocampal place cell activity sequences

    PubMed Central

    Takahashi, Susumu

    2015-01-01

    Episodic memory retrieval of events at a specific place and time is effective for future planning. Sequential reactivation of the hippocampal place cells along familiar paths while the animal pauses is well suited to such a memory retrieval process. It is, however, unknown whether this awake replay represents events occurring along the path. Using a subtask switching protocol in which the animal experienced three subtasks as ‘what’ information in a maze, I here show that the replay represents a trial type, consisting of path and subtask, in terms of neuronal firing timings and rates. The actual trial type to be rewarded could only be reliably predicted from replays that occurred at the decision point. This trial-type representation implies that not only ‘where and when’ but also ‘what’ information is contained in the replay. This result supports the view that awake replay is an episodic-like memory retrieval process. DOI: http://dx.doi.org/10.7554/eLife.08105.001 PMID:26481131

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

    PubMed

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

    2011-02-01

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

  13. Time decay of object, place and temporal order memory in a paradigm assessing simultaneously episodic-like memory components in mice.

    PubMed

    Belblidia, Hassina; Abdelouadoud, Abdelmalek; Jozet-Alves, Christelle; Dumas, Hélène; Freret, Thomas; Leger, Marianne; Schumann-Bard, Pascale

    2015-06-01

    A common trait of numerous memory disorders is the impairment of episodic memory. Episodic memory is a delay-dependant memory, especially associating three components, the "what", "where" and "when" of a unique event. To investigate underlying mechanisms of such memory, several tests, mainly based on object exploration behaviour, have been set up in rodents. Recently, a three-trial object recognition task has been proposed to evaluate simultaneously the different components of episodic-like memory in rodents. However, to date, the time course of each memory component in this paradigm is not known. We characterised here the time course of memory decay in adult mice during the three-trial object recognition task, with inter-trial interval (ITI) ranging from 1h to 4h. We found that, with 1h and 2h, but not 4h ITI, mice spent more time to explore the displaced "old object" relative to the displaced "recent object", reflecting memory for "what and when". Concomitantly, animals exhibited more exploration time for the displaced "old object" relative to the stationary "old object", reflecting memory for "what and where". These results provide strong evidence that mice establish an integrated memory for unique experience consisting of the "what", "where" and "when" that can persist until 2h ITI.

  14. Final report for the endowment of simulator agents with human-like episodic memory LDRD.

    SciTech Connect

    Speed, Ann Elizabeth; Lippitt, Carl Edward; Thomas, Edward Victor; Xavier, Patrick Gordon; Forsythe, Christi A.; Schaller, Mark J.; Schoenwald, David Alan

    2003-12-01

    This report documents work undertaken to endow the cognitive framework currently under development at Sandia National Laboratories with a human-like memory for specific life episodes. Capabilities have been demonstrated within the context of three separate problem areas. The first year of the project developed a capability whereby simulated robots were able to utilize a record of shared experience to perform surveillance of a building to detect a source of smoke. The second year focused on simulations of social interactions providing a queriable record of interactions such that a time series of events could be constructed and reconstructed. The third year addressed tools to promote desktop productivity, creating a capability to query episodic logs in real time allowing the model of a user to build on itself based on observations of the user's behavior.

  15. Effect of Anserine/Carnosine Supplementation on Verbal Episodic Memory in Elderly People

    PubMed Central

    Hisatsune, Tatsuhiro; Kaneko, Jun; Kurashige, Hiroki; Cao, Yuan; Satsu, Hideo; Totsuka, Mamoru; Katakura, Yoshinori; Imabayashi, Etsuko; Matsuda, Hiroshi

    2015-01-01

    Our goal in this study was to determine whether or not anserine/carnosine supplementation (ACS) is capable of preserving cognitive function of elderly people. In a double-blind randomized controlled trial, volunteers were randomly assigned to an ACS or placebo group at a 1:1 ratio. The ACS group took 1.0 g of an anserine/carnosine (3:1) formula daily for 3 months. Participants were evaluated by psychological tests before and after the 3-month supplementation period. Thirty-nine healthy elderly volunteers (60–78 years old) completed the follow-up tests. Among the tests, delayed recall verbal memory assessed by the Wechsler Memory Scale-Logical Memory showed significant preservation in the ACS group, compared to the placebo group (p = 0.0128). Blood analysis revealed a decreased secretion of inflammatory cytokines, including CCL-2 and IL-8, in the ACS group. MRI analysis using arterial spin labeling showed a suppression in the age-related decline in brain blood flow in the posterior cingulate cortex area in the ACS group, compared to the placebo group (p = 0.0248). In another randomized controlled trial, delayed recall verbal memory showed significant preservation in the ACS group, compared to the placebo group (p = 0.0202). These results collectively suggest that ACS may preserve verbal episodic memory and brain perfusion in elderly people, although further study is needed. PMID:26682691

  16. Individual Motivations and Characteristics Associated with Bystander Intervention during Bullying Episodes among Children and Youth

    ERIC Educational Resources Information Center

    Cappadocia, M. Catherine; Pepler, Debra; Cummings, Joanne G.; Craig, Wendy

    2012-01-01

    The aim of the current study was to explore bystander experiences during bullying episodes among children and youth attending a residential summer camp by investigating rates of witnessing and intervention, as well as individual motivations and characteristics associated with bystander intervention. The majority of children had witnessed bullying…

  17. The effect of childhood bilingualism on episodic and semantic memory tasks.

    PubMed

    Kormi-Nouri, Reza; Shojaei, Razie-Sadat; Moniri, Sadegheh; Gholami, Ali-Reza; Moradi, Ali-Reza; Akbari-Zardkhaneh, Saeed; Nilsson, Lars-Göran

    2008-04-01

    Kormi-Nouri, Moniri and Nilsson (2003) demonstrated that Swedish-Persian bilingual children recalled at a higher level than Swedish monolingual children, when they were tested using Swedish materials. The present study was designed to examine the bilingual advantage of children who use different languages in their everyday life but have the same cultural background and live in their communities in the same way as monolingual children. In four experiments, 488 monolingual and bilingual children were compared with regard to episodic and semantic memory tasks. In experiments 1 and 2 there were 144 boys and 144 girls in three school groups (aged 9-10 years, 13-14 years and 16-17 years) and in three language groups (Persian monolingual, Turkish-Persian bilingual, and Kurdish-Persian bilingual). In experiments 3 and 4, there were 200 male students in two school groups (aged 9-10 years and 16-17 years) and in two language groups (Persian monolingual and Turkish-Persian bilingual). In the episodic memory task, children learned sentences (experiments 1-3) and words (Experiment 4). Letter and category fluency tests were used as measures of semantic memory. To change cognitive demands in memory tasks, in Experiment 1, the integration of nouns and verbs within sentences was manipulated by the level of association between verb and noun in each sentence. At retrieval, a recognition test was used. In experiments 2 and 3, the organization between sentences was manipulated at encoding in Experiment 2 and at both encoding and retrieval in Experiment 3 through the use of categories among the objects. At retrieval, free recall or cued recall tests were employed. In Experiment 4, the bilingual children were tested with regard to both their first and their second language. In all four experiments, a positive effect of bilingualism was found on episodic and semantic memory tasks; the effect was more pronounced for older than younger children. The bilingual advantage was not affected by

  18. 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

    2017-04-03

    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.

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

    ERIC Educational Resources Information Center

    Furman, Orit; Mendelsohn, Avi; Dudai, Yadin

    2012-01-01

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

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

    ERIC Educational Resources Information Center

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

    2011-01-01

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

  1. When You've Seen One, Have You Seen Them All? Children's Memory for General and Specific Learning Episodes

    ERIC Educational Resources Information Center

    Riggs, Anne E.; Kalish, Charles W.; Alibali, Martha W.

    2014-01-01

    In any learning situation, children must decide the level of generality with which to encode information. Cues to generality may affect children's memory for different components of a learning episode. In this research, we investigated whether 1 cue to generality, generic language, affects children's memory for information about social categories…

  2. Alzheimer's disease can spare local metacognition despite global anosognosia: revisiting the confidence-accuracy relationship in episodic memory.

    PubMed

    Gallo, David A; Cramer, Stefanie J; Wong, Jessica T; Bennett, David A

    2012-07-01

    Alzheimer's disease (AD) can impair metacognition in addition to more basic cognitive functions like memory. However, while global metacognitive inaccuracies are well documented (i.e., low deficit awareness, or anosognosia), the evidence is mixed regarding the effects of AD on local or task-based metacognitive judgments. Here we investigated local metacognition with respect to the confidence-accuracy relationship in episodic memory (i.e., metamemory). AD and control participants studied pictures of common objects and their verbal labels, and then took forced-choice picture recollection tests using the verbal labels as retrieval cues. We found that item-based confidence judgments discriminated between accurate and inaccurate recollection responses in both groups, implicating relatively spared metamemory in AD. By contrast, there was evidence for global metacognitive deficiencies, as AD participants underestimated the severity of their everyday problems compared to an informant's assessment. Within the AD group, individual differences in global metacognition were related to recollection accuracy, and global metacognition for everyday memory problems was related to task-based metacognitive accuracy. These findings suggest that AD can spare the confidence-accuracy relationship in recollection tasks, and that global and local metacognition measures tap overlapping neuropsychological processes.

  3. Alzheimer’s Disease Can Spare Local Metacognition Despite Global Anosognosia: Revisiting the Confidence-Accuracy Relationship in Episodic Memory

    PubMed Central

    Gallo, David A.; Cramer, Stefanie J.; Wong, Jessica T.; Bennett, David A.

    2012-01-01

    Alzheimer’s Disease (AD) can impair metacognition in addition to more basic cognitive functions like memory. However, while global metacognitive inaccuracies are well documented (i.e., low deficit awareness, or anosognosia), the evidence is mixed regarding the effects of AD on local or task-based metacognitive judgments. Here we investigated local metacognition with respect to the confidence-accuracy relationship in episodic memory (i.e., metamemory). AD and control participants studied pictures of common objects and their verbal labels, and then took forced-choice picture recollection tests using the verbal labels as retrieval cues. We found that item-based confidence judgments discriminated between accurate and inaccurate recollection responses in both groups, implicating relatively spared metamemory in AD. By contrast, there was evidence for global metacognitive deficiencies, as AD participants underestimated the severity of their everyday problems compared to an informant’s assessment. Within the AD group, individual differences in global metacognition were related to recollection accuracy, and global metacognition for everyday memory problems was related to task-based metacognitive accuracy. These findings suggest that AD can spare the confidence-accuracy relationship in recollection tasks, and that global and local metacognition measures tap overlapping neuropsychological processes. PMID:22722068

  4. Episodic memory loss is related to hippocampal-mediated beta-amyloid deposition in elderly subjects.

    PubMed

    Mormino, E C; Kluth, J T; Madison, C M; Rabinovici, G D; Baker, S L; Miller, B L; Koeppe, R A; Mathis, C A; Weiner, M W; Jagust, W J

    2009-05-01

    Although beta-amyloid (Abeta) plaques are a primary diagnostic criterion for Alzheimer's disease, this pathology is commonly observed in the brains of non-demented older individuals. To explore the importance of this pathology in the absence of dementia, we compared levels of amyloid deposition (via 'Pittsburgh Compound-B' (PIB) positron emission tomography (PET) imaging) to hippocampus volume (HV) and episodic memory (EM) in three groups: (i) normal controls (NC) from the Berkeley Aging Cohort (BAC NC, n = 20); (ii) normal controls (NC) from the Alzheimer's disease neuroimaging initiative (ADNI NC, n = 17); and (iii) PIB+ mild cognitive impairment subjects from the ADNI (ADNI PIB+ MCI, n = 39). Age, gender and education were controlled for in each statistical model, and HV was adjusted for intracranial volume (aHV). In BAC NC, elevated PIB uptake was significantly associated with smaller aHV (P = 0.0016) and worse EM (P = 0.0086). Within ADNI NC, elevated PIB uptake was significantly associated with smaller aHV (P = 0.047) but not EM (P = 0.60); within ADNI PIB+ MCI, elevated PIB uptake was significantly associated with both smaller aHV (P = 0.00070) and worse EM (P = 0.046). To further understand these relationships, a recursive regression procedure was conducted within all ADNI NC and PIB+ MCI subjects (n = 56) to test the hypothesis that HV mediates the relationship between Abeta and EM. Significant correlations were found between PIB index and EM (P = 0.0044), PIB index and aHV (P < 0.0001), as well as between aHV and EM (P < 0.0001). When both aHV and PIB were included in the same model to predict EM, aHV remained significant (P = 0.0015) whereas PIB index was no longer significantly associated with EM (P = 0.50). These results are consistent with a model in which Abeta deposition, hippocampal atrophy, and EM occur sequentially in elderly subjects, with Abeta deposition as the primary event in this cascade. This pattern suggests that declining EM in older

  5. Prediction of the period of psychotic episode in individual schizophrenics by simulation-data construction approach.

    PubMed

    Huang, Chun-Jung; Wang, Hsiao-Fan; Chiu, Hsien-Jane; Lan, Tsuo-Hung; Hu, Tsung-Ming; Loh, El-Wui

    2010-10-01

    Although schizophrenia can be treated, most patients still experience inevitable psychotic episodes from time to time. Precautious actions can be taken if the next onset can be predicted. However, sufficient information is always lacking in the clinical scenario. A possible solution is to use the virtual data generated from limited of original data. Data construction method (DCM) has been shown to generate the virtual felt earthquake data effectively and used in the prediction of further events. Here we investigated the performance of DCM in deriving the membership functions and discrete-event simulations (DES) in predicting the period embracing the initiation and termination time-points of the next psychotic episode of 35 individual schizophrenic patients. The results showed that 21 subjects had a success of simulations (RSS) ≥70%. Further analysis demonstrated that the co-morbidity of coronary heart diseases (CHD), risks of CHD, and the frequency of previous psychotic episodes increased the RSS.

  6. Executive Functions Are Employed to Process Episodic and Relational Memories in Children With Autism Spectrum Disorders

    PubMed Central

    2013-01-01

    Objective: Long-term memory functioning in autism spectrum disorders (ASDs) is marked by a characteristic pattern of impairments and strengths. Individuals with ASD show impairment in memory tasks that require the processing of relational and contextual information, but spared performance on tasks requiring more item-based, acontextual processing. Two experiments investigated the cognitive mechanisms underlying this memory profile. Method: A sample of 14 children with a diagnosis of high-functioning ASD (age: M = 12.2 years), and a matched control group of 14 typically developing (TD) children (age: M = 12.1 years), participated in a range of behavioral memory tasks in which we measured both relational and item-based memory abilities. They also completed a battery of executive function measures. Results: The ASD group showed specific deficits in relational memory, but spared or superior performance in item-based memory, across all tasks. Importantly, for ASD children, executive ability was significantly correlated with relational memory but not with item-based memory. No such relationship was present in the control group. This suggests that children with ASD atypically employed effortful, executive strategies to retrieve relational (but not item-specific) information, whereas TD children appeared to use more automatic processes. Conclusions: The relational memory impairment in ASD may result from a specific impairment in automatic associative retrieval processes with an increased reliance on effortful and strategic retrieval processes. Our findings allow specific neural predictions to be made regarding the interactive functioning of the hippocampus, prefrontal cortex, and posterior parietal cortex in ASD as a neural network supporting relational memory processing. PMID:24245930

  7. Fornix microstructure and memory performance is associated with altered neural connectivity during episodic recognition

    PubMed Central

    Ly, Martina; Adluru, Nagesh; Destiche, Daniel J.; Lu, Sharon Y.; Oh, Jennifer M.; Hoscheidt, Siobhan M.; Alexander, Andrew L.; Okonkwo, Ozioma C.; Rowley, Howard A.; Sager, Mark A.; Johnson, Sterling C.; Bendlin, Barbara B.

    2015-01-01

    Objective The purpose of this study was to assess whether age-related differences in white matter microstructure are associated with altered task-related connectivity during episodic recognition. Method Using functional magnetic resonance imaging and diffusion tensor imaging from 282 cognitively healthy middle-to-late aged adults enrolled in the Wisconsin Registry for Alzheimer's Prevention, we investigated whether fractional anisotropy (FA) within white matter regions known to decline with age was associated with task-related connectivity within the recognition network. Results There was a positive relationship between fornix FA and memory performance, both of which negatively correlated with age. Psychophysiological interaction analyses revealed that higher fornix FA was associated with increased task-related connectivity amongst the hippocampus, caudate, precuneus, middle occipital gyrus, and middle frontal gyrus. In addition, better task performance was associated with increased task-related connectivity between the posterior cingulate gyrus, middle frontal gyrus, cuneus, and hippocampus. Conclusions The findings indicate that age has a negative effect on white matter microstructure, which in turn has a negative impact on memory performance. However, fornix microstructure did not significantly mediate the effect of age on performance. Interestingly, dynamic functional connectivity was associated with better memory performance. The results of the psychophysiological interaction analysis further revealed that alterations in fornix microstructure explain–at least in part–connectivity among cortical regions in the recognition memory network. Our results may further elucidate the relationship between structural connectivity, neural function, and cognition. PMID:26888616

  8. 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

  9. Role of Aging and Hippocampus in Time-Place Learning: Link to Episodic-Like Memory?

    PubMed Central

    Mulder, C. K.; Gerkema, M. P.; Van der Zee, E. A.

    2016-01-01

    Introduction: With time-place learning (TPL), animals link an event with the spatial location and the time of day (TOD). The what–where–when TPL components make the task putatively episodic-like in nature. Animals use an internal sense of time to master TPL, which is circadian system based. Finding indications for a role of the hippocampus and (early) aging-sensitivity in TPL would strengthen the episodic-like memory nature of the paradigm. Methods: Previously, we used C57Bl/6 mice for our TPL research. Here, we used CD1 mice which are less hippocampal-driven and age faster compared to C57Bl/6 mice. To demonstrate the low degree of hippocampal-driven performance in CD1 mice, a cross maze was used. The spontaneous alternation test was used to score spatial working memory in CD1 mice at four different age categories (young (3–6 months), middle-aged (7–11 months), aged (12–18 months) and old (>19 months). TPL performance of middle-aged and aged CD1 mice was tested in a setup with either two or three time points per day (2-arm or 3-arm TPL task). Immunostainings were applied on brains of young and middle-aged C57Bl/6 mice that had successfully mastered the 3-arm TPL task. Results: In contrast to C57Bl/6 mice, middle-aged and aged CD1 mice were less hippocampus-driven and failed to master the 3-arm TPL task. They could, however, master the 2-arm TPL task primarily via an ordinal (non-circadian) timing system. c-Fos, CRY2, vasopressin (AVP), and phosphorylated cAMP response element-binding protein (pCREB) were investigated. We found no differences at the level of the suprachiasmatic nucleus (SCN; circadian master clock), whereas CRY2 expression was increased in the hippocampal dentate gyrus (DG). The most pronounced difference between TPL trained and control mice was found in c-Fos expression in the paraventricular thalamic nucleus, a circadian system relay station. Conclusions: These results further indicate a key role of CRY proteins in TPL and confirm the

  10. 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

  11. To boost or to CRUNCH? Effect of effortful encoding on episodic memory in older adults is dependent on executive functioning

    PubMed Central

    Fu, Li; Maes, Joseph H. R.; Kessels, Roy P. C.; Daselaar, Sander M.

    2017-01-01

    It is essential to develop effective interventions aimed at ameliorating age-related cognitive decline. Previous studies found that effortful encoding benefits episodic memory in older adults. However, to date it is unclear whether this benefit is different for individuals with strong versus weak executive functioning (EF). Fifty-one older adults were recruited and divided into low (N = 26) and high (N = 25) functioning groups, based on their EF capacity. All participants performed a semantic and a perceptual incidental encoding task. Each encoding task was performed under four difficulty levels to establish different effort levels. Encoding was followed by a recognition task. Results showed that the high EF group benefitted from increased effort in both tasks. However, the low EF group only showed a beneficial effect under low levels of effort. Results are consistent with the Compensation-Related Utilization of Neural Circuits Hypothesis (CRUNCH) and suggest that future research directed at developing efficient memory strategies to reduce negative cognitive aging effects should take individual cognitive differences among older adults into account, such as differences in EF. PMID:28328979

  12. Domain-general signals in the cingulo-opercular network for visuospatial attention and episodic memory.

    PubMed

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

    2014-03-01

    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 behaviorally 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 pFC, 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 frontoparietal 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.

  13. Memory strengthening by a real-life episode during reconsolidation: an outcome of water deprivation via brain angiotensin II.

    PubMed

    Frenkel, Lia; Maldonado, Héctor; Delorenzi, Alejandro

    2005-10-01

    A considerable body of evidence reveals that consolidated memories, recalled by a reminder, enter into a new vulnerability phase during which they are susceptible to disruption again. Consistently, reconsolidation was shown by the amnesic effects induced by administration of consolidation blockers after memory labilization. To shed light on the functional value of reconsolidation, we explored whether an endogenous process activated during a concurrent real-life experience improved this memory phase. Reconsolidation of long-term contextual memory has been well documented in the crab Chasmagnathus. Previously we showed that angiotensin II facilitates memory consolidation. Moreover, water deprivation increases brain angiotensin and improves memory consolidation and retrieval through angiotensin II receptors. Here, we tested whether concurrent water deprivation improves reconsolidation via endogenous angiotensin and therefore strengthens memory. We show that memory reconsolidation, induced by training context re-exposure, is facilitated by a concurrent episode of water deprivation, which induces a raise in endogenous brain angiotensin II. Positive modulation is expressed by full memory retention, despite a weak training, 24 or 72 but not 4 h after memory reactivation. This is the first evidence that memory can be positively modulated during reconsolidation through an identified endogenous process triggered during a real-life episode. We propose that the functional value for reconsolidation would be to make possible a change in memory strength by the influence of a concurrent experience. Reconsolidation improvement would lead to memory re-evaluation, not by altering memory content but by modifying the behaviour as an outcome of changing the hierarchy of the memories that control it.

  14. Event Congruency Enhances Episodic Memory Encoding through Semantic Elaboration and Relational Binding

    PubMed Central

    Staresina, Bernhard P.; Gray, James C.

    2009-01-01

    Behavioral research consistently shows that congruous events, that is, events whose constituent elements match along some specific dimension, are better remembered than incongruous events. Although it has been speculated that this “congruency subsequent memory effect” (cSME) results from enhanced semantic elaboration, empirical evidence for this account is lacking. Here, we report a set of behavioral and neuroimaging experiments demonstrating that congruous events engage regions along the left inferior frontal gyrus (LIFG)—consistently related to semantic elaboration—to a significantly greater degree than incongruous events, providing evidence in favor of this hypothesis. Critically, we additionally report 3 novel findings in relation to event congruency: First, congruous events yield superior memory not only for a given study item but also for associated source details. Second, the cSME is evident not only for events that matched a semantic context but also for those that matched a subjective aesthetic schema. Finally, functional magnetic resonance imaging brain/behavior correlation analysis reveals a strong link between 1) across-subject variation in the magnitude of the cSME and 2) differential right hippocampal activation, suggesting that episodic memory for congruous events is effectively bolstered by the extent to which semantic associations are generated and relationally integrated via LIFG-hippocampal–encoding mechanisms. PMID:18820289

  15. Age and active navigation effects on episodic memory: A virtual reality study.

    PubMed

    Sauzéon, Hélène; N'Kaoua, Bernard; Arvind Pala, Prashant; Taillade, Mathieu; Guitton, Pascal

    2016-02-01

    We investigated the navigation-related age effects on learning, proactive interference semantic clustering, recognition hits, and false recognitions in a naturalistic situation using a virtual apartment-based task. We also examined the neuropsychological correlates (executive functioning [EF] and episodic memory) of navigation-related age effects on memory. Younger and older adults either actively navigated or passively followed the computer-guided tour of an apartment. The results indicated that active navigation increased recognition hits compared with passive navigation, but it did not influence other memory measures (learning, proactive interference, and semantic clustering) to a similar extent in either age group. Furthermore, active navigation helped to reduce false recognitions in younger adults but increased those made by older adults. This differential effect of active navigation for younger and older adults was accounted for by EF score. Like for the subject-performed task effects, the effects from the navigation manipulation were well accounted for by item-specific/relational processing distinction, and they were also consistent with a source monitoring deficit in older adults.

  16. Frequency and predictors of self-reported prospective memory complaints in individuals infected with HIV.

    PubMed

    Woods, Steven Paul; Carey, Catherine L; Moran, Lisa M; Dawson, Matthew S; Letendre, Scott L; Grant, Igor

    2007-02-01

    Failures of episodic retrospective memory (RetM) are among the most frequently reported cognitive complaints endorsed by individuals living with HIV infection. The present study sought to examine the nature, frequency, and determinants of self-reported complaints of prospective memory (ProM) in HIV, which is a singly dissociable and ecologically relevant aspect of episodic memory involving the execution of future intentions. Seventy-five HIV seropositive individuals and 60 seronegative volunteers were administered the Prospective and Retrospective Memory Questionnaire (PMRQ) as part of extensive neuropsychological, psychiatric, and medical research assessments. The HIV sample endorsed more frequent ProM complaints in daily life than the seronegative group, particularly on items requiring self-initiated cue detection and retrieval. Within both study groups, ProM complaints were significantly more frequent than RetM complaints. Although the HIV sample was impaired relative to the seronegative group on an objective, performance-based ProM test, self-reported ProM complaints did not correspond to actual ProM abilities. However, greater frequency of self-reported ProM complaints was moderately associated with increased fatigue, as well as with symptoms of anxiety and depression. Consistent with prior research on RetM in HIV, results indicate that affective distress contributes to a metamemory deficit for HIV-associated ProM impairment, which highlights the potential importance of assessing both self-reported and performance-based ProM in clinical and research neuroAIDS evaluations.

  17. Memory for Self-Performed Actions in Individuals with Asperger Syndrome

    PubMed Central

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

    2010-01-01

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

  18. Elevated levels of serum cholesterol are associated with better performance on tasks of episodic memory.

    PubMed

    Leritz, Elizabeth C; McGlinchey, Regina E; Salat, David H; Milberg, William P

    2016-04-01

    We examined how serum cholesterol, an established risk factor for cerebrovascular disease (CVD), relates to cognitive function in healthy middle-older aged individuals with no neurologic or CVD history. A complete lipid panel was obtained from a cohort of one hundred twenty individuals, ages 43-85, who also underwent a comprehensive neuropsychological examination. In order to reduce the number of variables and empirically identify broad cognitive domains, scores from neuropsychological tests were submitted into a factor analysis. This analysis revealed three explainable factors: Memory, Executive Function and Memory/Language. Three separate hierarchical multiple regression analyses were conducted using individual cholesterol metrics (total cholesterol, low density lipoprotein; LDL, high density lipoprotein; HDL, and triglycerides), as well as age, education, medication status (lipid lowering agents), ApoE status, and additional risk factors for CVD to predict neuropsychological function. The Memory Factor was predicted by a combination of age, LDL, and triglyceride levels; both age and triglycerides were negatively associated with factor score, while LDL levels revealed a positive relationship. Both the Executive and Memory/Language factor were only explained by education, whereby more years were associated with better performance. These results provide evidence that individual cholesterol lipoproteins and triglycerides may differentially impact cognitive function, over and above other common CVD risk factors and ApoE status. Our findings demonstrate the importance of consideration of vascular risk factors, such as cholesterol, in studies of cognitive aging.

  19. Do memory-impaired individuals report stable attitudes?

    PubMed

    Haddock, Geoffrey; Newson, Margaret; Haworth, Judy

    2011-06-01

    This research explored whether individuals diagnosed with probable Alzheimer's disease report stable attitudes. Two groups of participants (16 memory-impaired individuals with dementia and 16 matched controls without memory impairment) were presented with photos of various common objects and asked to indicate their attitude towards each object. Participants completed this task on two occasions, separated by 1 week. The results of the experiment revealed that memory-impaired individuals showed significant stability across time in their attitudes, although their level of attitude stability was less pronounced than that demonstrated by the matched controls. Theoretical and applied implications of the results are discussed.

  20. Age-Related Reduction of the Confidence-Accuracy Relationship in Episodic Memory: Effects of Recollection Quality and Retrieval Monitoring

    PubMed Central

    Wong, Jessica T.; Cramer, Stefanie J.; Gallo, David A.

    2012-01-01

    We investigated age-related reductions in episodic metamemory accuracy. Participants studied pictures and words in different colors, and then took forced-choice recollection tests. These tests required recollection of the earlier presentation color, holding familiarity of the response options constant. Metamemory accuracy was assessed for each participant by comparing recollection test accuracy to corresponding confidence judgments. We found that recollection test accuracy was greater in younger than older adults, and also for pictures than font color. Metamemory accuracy tracked each of these recollection differences, as well as individual differences in recollection test accuracy within each age group, suggesting that recollection ability affects metamemory accuracy. Critically, the age-related impairment in metamemory accuracy persisted even when the groups were matched on recollection test accuracy, suggesting that metamemory declines were not entirely due to differences in recollection frequency or quantity, but that differences in recollection quality and/or monitoring also played a role. We also found that age-related impairments in recollection and metamemory accuracy were equivalent for pictures and font colors. This result contrasted with previous false recognition findings, which predicted that older adults would be differentially impaired when monitoring memory for less distinctive memories. These and other results suggest that age-related reductions in metamemory accuracy are not entirely attributable to false recognition effects, but also depend heavily on deficient recollection and/or monitoring of specific details associated with studied stimuli. PMID:22449027

  1. The role of movement representation in episodic memory for actions: A study of patients with apraxia.

    PubMed

    Masumoto, Kouhei; Shirakawa, Masayuki; Higashiyama, Takeshi; Yokoyama, Kazumasa

    2015-01-01

    In attempting to memorize a sentence about an action, such as "Pick up the glass," performing the action (motor encoding) results in better memory performance than simply memorizing the words (verbal encoding). Such enhancement of memory is known as the enactment effect. Several theories have been proposed to explain this phenomenon using concepts such as physical motor information associated with speed, form, amplitude of movement and/or movement representations involved in movement imaging, knowledge on manipulating tools, and spatial relationships in the enactment effect. However, there have been no cognitive neuropsychological studies investigating whether the enactment effect is crucially influenced by physical motor information or movement representations. To clarify this issue, we compared healthy adult control participants with two different types of apraxia patients. One patient with left hemisphere lesions caused by cerebral infarction had a disability involving multiple movement representations. The other patient showed symptoms of corticobasal syndrome and was not able to benefit from feedback on the accuracy of her motor movements during enactment. Participants memorized action sentences via either verbal or motor encoding and responded to recall and recognition tests. Results indicated that the patient with the movement representation deficits exhibited worse memory performance than the other patient or control participants following both verbal and motor encoding. Although the enactment effect was present during recall in both patients, the effect was not observed for recognition in the patient with severe movement representation deficits. These results suggest that movement representations are involved in encoding episodic memories of action. Moreover, the role of movement representations appears to depend on the form of retrieval that is being used.

  2. Low Perceived Control as a Risk Factor for Episodic Memory: The Mediational Role of Anxiety and Task Interference

    PubMed Central

    Lachman, Margie E.; Agrigoroaei, Stefan

    2011-01-01

    Low perceived control is considered a risk factor for poor cognitive functioning, but the mechanisms are unclear. The goal of this study was to analyze anxiety and task interference as sequential mediators of the association between control beliefs and episodic memory. Cognitive-specific control beliefs were assessed prior to the lab session. State anxiety was assessed in the lab followed by a word list recall task. The frequency of intrusive thoughts during the memory task was reported by the participants as a measure of task interference after the completion of the cognitive testing. The results for 152 participants aged 22 to 84 years supported the predicted three-path mediation model. Lower levels of control beliefs were associated with higher state anxiety, which in turn affected episodic memory performance by increasing the likelihood of task interference, with age, sex, and verbal abilities as covariates. The implications of the results for developing interventions to improve memory performance are considered. PMID:21918911

  3. A categorical recall strategy does not explain animacy effects in episodic memory.

    PubMed

    VanArsdall, Joshua E; Nairne, James S; Pandeirada, Josefa N S; Cogdill, Mindi

    2017-04-01

    Animate stimuli are better remembered than matched inanimate stimuli in free recall. Three experiments tested the hypothesis that animacy advantages are due to a more efficient use of a categorical retrieval cue. Experiment 1 developed an "embedded list" procedure that was designed to disrupt participants' ability to perceive category structure at encoding; a strong animacy effect remained. Experiments 2 and 3 employed animate and inanimate word lists consisting of tightly constrained categories (four-footed animals and furniture). Experiment 2 failed to find an animacy advantage when the categorical structure was readily apparent, but the advantage returned in Experiment 3 when the embedded list procedure was employed using the same target words. These results provide strong evidence against an organizational account of the animacy effect, indicating that the animacy effect in episodic memory is probably due to item-specific factors related to animacy.

  4. The late negative episodic memory effect: the effect of recapitulating study details at test.

    PubMed

    Friedman, David; Cycowicz, Yael M; Bersick, Michael

    2005-05-01

    An hypothesis concerning mnemonic function suggests that perceptual details of previously experienced episodes are retrieved from the cortices that initially processed that information during the encoding phase. Cycowicz et al. [Cycowicz, Y.M., Friedman, D. and Snodgrass, J.G., Remembering the color of objects: an ERP investigation of source memory, Cereb Cortex, 11 (2001) 322-334.] have interpreted the presence of a late negative episodic memory (EM) effect, maximal over parieto-occipital scalp, as a brain signature of the search for and/or retrieval/evaluation of the specific perceptual source-specifying attributes (i.e., color) of pictures in the visual cortical regions that were recruited during the encoding of that information. The present study assessed the validity of this hypothesis. Twelve participants studied pictures outlined in red or green and were subsequently tested with inclusion (i.e., item; old or new regardless of color) and exclusion (i.e., source; same color, different color/new judgments) tasks. In both, old pictures were presented either in the same color as at study or in the alternate color. A late negative, parieto-occipital EM effect was of much larger amplitude in the source compared to the item task. It was of similar magnitude to correctly recognized pictures whose colors were identical at study and test relative to those whose colors changed, and was not modulated by the success or failure of the source retrieval. These data run counter to the initial hypothesis that the late negative EM effect reflects the search for and/or retrieval of specific perceptual attributes such as color. Rather, the late negative EM effect may reflect the search for and/or retrieval/evaluation of more general source-specifying information in the cortical regions that initially processed the stimuli.

  5. A model of episodic memory: mental time travel along encoded trajectories using grid cells.

    PubMed

    Hasselmo, Michael E

    2009-11-01

    The definition of episodic memory includes the concept of mental time travel: the ability to re-experience a previously experienced trajectory through continuous dimensions of space and time, and to recall specific events or stimuli along this trajectory. Lesions of the hippocampus and entorhinal cortex impair human episodic memory function and impair rat performance in tasks that could be solved by retrieval of trajectories. Recent physiological data suggests a novel model for encoding and retrieval of trajectories, and for associating specific stimuli with specific positions along the trajectory. During encoding in the model, external input drives the activity of head direction cells. Entorhinal grid cells integrate the head direction input to update an internal representation of location, and drive hippocampal place cells. Trajectories are encoded by Hebbian modification of excitatory synaptic connections between hippocampal place cells and head direction cells driven by external action. Associations are also formed between hippocampal cells and sensory stimuli. During retrieval, a sensory input cue activates hippocampal cells that drive head direction activity via previously modified synapses. Persistent spiking of head direction cells maintains the direction and speed of the action, updating the activity of entorhinal grid cells that thereby further update place cell activity. Additional cells, termed arc length cells, provide coding of trajectory segments based on the one-dimensional arc length from the context of prior actions or states, overcoming ambiguity where the overlap of trajectory segments causes multiple head directions to be associated with one place. These mechanisms allow retrieval of complex, self-crossing trajectories as continuous curves through space and time.

  6. Episodic future thinking: the role of working memory and inhibition on age-related differences.

    PubMed

    Zavagnin, Michela; De Beni, Rossana; Borella, Erika; Carretti, Barbara

    2016-02-01

    The ability to remember past events and imagine future events (episodic future thinking-EFT) has been shown to decline with aging. However, only few studies have analyzed the cognitive mechanisms involved in EFT in both young and older adults. The present study examined the role of working memory and inhibition on age-related differences between young and older adults in EFT, in response to short sentences reflecting common events, some of which were repeated in both conditions (past and future). Thirty-seven young and 36 older adults completed an adapted version of the autobiographical interview, in which sentences were presented. Results showed that processing resources explained a significant part of the variance in the amount of details; in particular, inhibition explained the amount of external details produced in the future condition. In addition, using sentences, the older group did not differ from the young adults in terms of the proportion of internal details recalled in the past condition, whereas they produced a lower proportion of internal details in the future condition. The effect of using structured material was reinforced by repeating some sentences in the past. Further, only older adults rated the remembered episodes as more emotionally salient and relevant than the imagined ones. Age-related differences between young and older adults in EFT appear to depend on the type of material used, on basic mechanisms of cognition, and are characterized by both quantitative and qualitative differences.

  7. Cerebral White Matter Lesions and Affective Episodes Correlate in Male Individuals with Bipolar Disorder

    PubMed Central

    Birner, Armin; Seiler, Stephan; Lackner, Nina; Bengesser, Susanne A.; Queissner, Robert; Fellendorf, Frederike T.; Platzer, Martina; Ropele, Stefan; Enzinger, Christian; Schwingenschuh, Petra; Mangge, Harald; Pirpamer, Lukas; Deutschmann, Hannes; McIntyre, Roger S.; Kapfhammer, Hans-Peter; Reininghaus, Bernd; Reininghaus, Eva Z.

    2015-01-01

    Background Cerebral white matter lesions (WML) have been found in normal aging, vascular disease and several neuropsychiatric conditions. Correlations of WML with clinical parameters in BD have been described, but not with the number of affective episodes, illness duration, age of onset and Body Mass Index in a well characterized group of euthymic bipolar adults. Herein, we aimed to evaluate the associations between bipolar course of illness parameters and WML measured with volumetric analysis. Methods In a cross-sectional study 100 euthymic individuals with BD as well as 54 healthy controls (HC) were enrolled to undergo brain magnetic resonance imaging using 3T including a FLAIR sequence for volumetric assessment of WML-load using FSL-software. Additionally, clinical characteristics and psychometric measures including Structured Clinical Interview according to DSM-IV, Hamilton-Depression, Young Mania Rating Scale and Beck’s Depression Inventory were evaluated. Results Individuals with BD had significantly more (F = 3.968, p < .05) WML (Mdn = 3710mm3; IQR = 2961mm3) than HC (Mdn = 2185mm3; IQR = 1665mm3). BD men (Mdn = 4095mm3; IQR = 3295mm3) and BD women (Mdn = 3032mm3; IQR = 2816mm3) did not significantly differ as to the WML-load or the number and type of risk factors for WML. However, in men only, the number of manic/hypomanic episodes (r = 0.72; p < .001) as well as depressive episodes (r = 0.51; p < .001) correlated positively with WML-load. Conclusions WML-load strongly correlated with the number of manic episodes in male BD patients, suggesting that men might be more vulnerable to mania in the context of cerebral white matter changes. PMID:26252714

  8. Specific impairment of "what-where-when" episodic-like memory in experimental models of temporal lobe epilepsy.

    PubMed

    Inostroza, Marion; Brotons-Mas, Jorge R; Laurent, François; Cid, Elena; de la Prida, Liset Menendez

    2013-11-06

    Episodic memory deficit is a common cognitive disorder in human temporal lobe epilepsy (TLE). However, no animal model of TLE has been shown to specifically replicate this cognitive dysfunction, which has limited its translational appeal. Here, using a task that tests for nonverbal correlates of episodic-like memory in rats, we show that kainate-treated TLE rats exhibit a selective impairment of the "what-where-when" memory while preserving other forms of hippocampal-dependent memories. Assisted by multisite silicon probes, we recorded from the dorsal hippocampus of behaving animals to control for seizure-related factors and to look for electrophysiological signatures of cognitive impairment. Analyses of hippocampal local field potentials showed that both the power of theta rhythm and its coordination across CA1 and the DG-measured as theta coherence and phase locking-were selectively disrupted. This disruption represented a basal condition of the chronic epileptic hippocampus that was linked to different features of memory impairment. Theta power was more correlated with the spatial than with the temporal component of the task, while measures of theta coordination correlated with the temporal component. We conclude that episodic-like memory, as tested in the what-where-when task, is specifically affected in experimental TLE and that the impairment of hippocampal theta activity might be central to this dysfunction.

  9. Dynamic changes in prefrontal cortex involvement during verbal episodic memory formation.

    PubMed

    Galli, Giulia; Feurra, Matteo; Pavone, Enea Francesco; Sirota, Miroslav; Rossi, Simone

    2017-02-24

    During encoding, the neural activity immediately before or during an event can predict whether that event will be later remembered. The contribution of brain activity immediately after an event to memory formation is however less known. Here, we used repetitive Transcranial Magnetic Stimulation (rTMS) to investigate the temporal dynamics of episodic memory encoding with a focus on post-stimulus time intervals. At encoding, rTMS was applied during the online processing of the word, at its offset, or 100, 200, 300 or 400ms thereafter. rTMS was delivered to the left ventrolateral (VLPFC) or dorsolateral prefrontal cortex (DLPFC). VLPFC rTMS during the first few hundreds of milliseconds after word offset disrupted subsequent recognition accuracy. We did not observe effects of DLPFC rTMS at any time point. These results suggest that encoding-related VLPFC engagement starts at a relatively late processing stage, and may reflect brain processes related to the offset of the stimulus.

  10. Streptococcal Immunity Is Constrained by Lack of Immunological Memory following a Single Episode of Pyoderma

    PubMed Central

    Pandey, Manisha; Ozberk, Victoria; Calcutt, Ainslie; Langshaw, Emma; Powell, Jessica; Rivera-Hernandez, Tania; Philips, Zachary; Batzloff, Michael R.; Good, Michael F.

    2016-01-01

    The immunobiology underlying the slow acquisition of skin immunity to group A streptococci (GAS), is not understood, but attributed to specific virulence factors impeding innate immunity and significant antigenic diversity of the type-specific M-protein, hindering acquired immunity. We used a number of epidemiologically distinct GAS strains to model the development of acquired immunity. We show that infection leads to antibody responses to the serotype-specific determinants on the M-protein and profound protective immunity; however, memory B cells do not develop and immunity is rapidly lost. Furthermore, antibodies do not develop to a conserved M-protein epitope that is able to induce immunity following vaccination. However, if re-infected with the same strain within three weeks, enduring immunity and memory B-cells (MBCs) to type-specific epitopes do develop. Such MBCs can adoptively transfer protection to naïve recipients. Thus, highly protective M-protein-specific MBCs may never develop following a single episode of pyoderma, contributing to the slow acquisition of immunity and to streptococcal endemicity in at-risk populations. PMID:28027314

  11. Relation between Olfactory Dysfunction and Episodic Verbal Memory in Early Parkinson’s Disease

    PubMed Central

    HANOĞLU, Lütfü; HAKYEMEZ, Hüsniye Aylin; ÖZER, Feriha; ÖZBEN, Serkan; DEMİRCİ, Sema; OĞUZ AKARSU, Emel

    2014-01-01

    Introduction Olfactory dysfunction is an early and common symptom in idiopathic Parkinson’s disease (IPD). Recently, the relation between olfactory dysfunction and cognitive loss in IPD has been reported. In our study, we aimed to investigate the relation between olfactory dysfunction and cognitive impairments in early IPD related with this theory. Methods In this study, we included 28 patients with stage 1 and stage 2 IPD according to the Hoehn-Yahr (H-Y) scale and 19 healthy participants. The University of Pennsylvania Smell Identification Test (UPSIT) was performed for evaluating olfactory function. For cognitive investigation in participants, the clock drawing test, Stroop test, verbal fluency test, Benton face recognition test (BFR), Benton line judgment orientation test (BLO), and Auditory Verbal Learning Test (AVLT) were performed. Results We found significantly lower UPSIT scores in the patient group compared to controls (p=.018). In the neuropsychological investigation, only Stroop test and BLOT test scores were significantly lower in the patient group compared to controls (p=.003, p=.002, respectively). We found a negative correlation between UPSIT scores and Stroop time (p=.033) and Stroop error (p=.037) and a positive correlation between UPSIT scores and SBST long-term memory scores (p=.016) in patients. Conclusion In our study, we found mild cognitive impairment related with visuospatial and executive functions in early-stage IPD compared to controls. But, in the patient group, we detected a different impairment pattern of memory and frontal functions that correlated with hyposmia. This different pattern might be indicating a subgroup of IPD characterized by low performance in episodic verbal memory, with accompanying olfactory dysfunction in the early stage.

  12. Effects of Enactment in Episodic Memory: A Pilot Virtual Reality Study with Young and Elderly Adults

    PubMed Central

    Jebara, Najate; Orriols, Eric; Zaoui, Mohamed; Berthoz, Alain; Piolino, Pascale

    2014-01-01

    None of the previous studies on aging have tested the influence of action with respect to the degree of interaction with the environment (active or passive navigation) and the source of itinerary choice (self or externally imposed), on episodic memory (EM) encoding. The aim of this pilot study was to explore the influence of these factors on feature binding (the association between what, where, and when) in EM and on the subjective sense of remembering. Navigation in a virtual city was performed by 64 young and 64 older adults in one of four modes of exploration: (1) passive condition where participants were immersed as passengers of a virtual car [no interaction, no itinerary control (IC)], (2) IC (the subject chose the itinerary, but did not drive the car), (3) low, or (4) high navigation control (the subject just moved the car on rails or drove the car with a steering-wheel and a gas pedal on a fixed itinerary, respectively). The task was to memorize as many events encountered in the virtual environment as possible along with their factual (what), spatial (where), and temporal (when) details, and then to perform immediate and delayed memory tests. An age-related decline was evidenced for immediate and delayed feature binding. Compared to passive and high navigation conditions, and regardless of age-groups, feature binding was enhanced by low navigation and IC conditions. The subjective sense of remembering was boosted by the IC in older adults. Memory performance following high navigation was specifically linked to variability in executive functions. The present findings suggest that the decision of the itinerary is beneficial to boost EM in aging, although it does not eliminate age-related deficits. Active navigation can also enhance EM when it is not too demanding for subjects’ cognitive resources. PMID:25566069

  13. Default network activation during episodic and semantic memory retrieval: A selective meta-analytic comparison.

    PubMed

    Kim, Hongkeun

    2016-01-08

    It remains unclear whether and to what extent the default network subregions involved in episodic memory (EM) and semantic memory (SM) processes overlap or are separated from one another. This study addresses this issue through a controlled meta-analysis of functional neuroimaging studies involving healthy participants. Various EM and SM task paradigms differ widely in the extent of default network involvement. Therefore, the issue at hand cannot be properly addressed without some control for this factor. In this regard, this study employs a two-stage analysis: a preliminary meta-analysis to select EM and SM task paradigms that recruit relatively extensive default network regions and a main analysis to compare the selected task paradigms. Based on a within-EM comparison, the default network contributed more to recollection/familiarity effects than to old/new effects, and based on a within-SM comparison, it contributed more to word/pseudoword effects than to semantic/phonological effects. According to a direct comparison of recollection/familiarity and word/pseudoword effects, each involving a range of default network regions, there were more overlaps than separations in default network subregions involved in these two effects. More specifically, overlaps included the bilateral posterior cingulate/retrosplenial cortex, left inferior parietal lobule, and left anteromedial prefrontal regions, whereas separations included only the hippocampal formation and the parahippocampal cortex region, which was unique to recollection/familiarity effects. These results indicate that EM and SM retrieval processes involving strong memory signals recruit extensive and largely overlapping default network regions and differ mainly in distinct contributions of hippocampus and parahippocampal regions to EM retrieval.

  14. Transcutaneous vagus nerve stimulation boosts associative memory in older individuals.

    PubMed

    Jacobs, Heidi I L; Riphagen, Joost M; Razat, Chantalle M; Wiese, Svenja; Sack, Alexander T

    2015-05-01

    Direct vagus nerve stimulation (dVNS) is known to improve mood, epilepsy, and memory. Memory improvements have been observed in Alzheimer's disease patients after long-term stimulation. The potential of transcutaneous vagus nerve stimulation (tVNS), a noninvasive alternative to dVNS, to alter memory performance remains unknown. We aimed to investigate the effect of a single-session tVNS on associative memory performance in healthy older individuals. To investigate this, we performed a single-blind sham-controlled randomized crossover pilot study in healthy older individuals (n = 30, 50% female). During the stimulation or sham condition, participants performed an associative face-name memory task. tVNS enhanced the number of hits of the memory task, compared with the sham condition. This effect was specific to the experimental task. Participants reported few side effects. We conclude that tVNS is a promising neuromodulatory technique to improve associative memory performance in older individuals, even after a single session. More research is necessary to investigate its underlying neural mechanisms, the impact of varying stimulation parameters, and its applicability in patients with cognitive decline.

  15. Contrasting Prefrontal Cortex Contributions to Episodic Memory Dysfunction in Behavioural Variant Frontotemporal Dementia and Alzheimer’s Disease

    PubMed Central

    Wong, Stephanie; Flanagan, Emma; Savage, Greg; Hodges, John R.; Hornberger, Michael

    2014-01-01

    Recent evidence has questioned the integrity of episodic memory in behavioural variant frontotemporal dementia (bvFTD), where recall performance is impaired to the same extent as in Alzheimer’s disease (AD). While these deficits appear to be mediated by divergent patterns of brain atrophy, there is evidence to suggest that certain prefrontal regions are implicated across both patient groups. In this study we sought to further elucidate the dorsolateral (DLPFC) and ventromedial (VMPFC) prefrontal contributions to episodic memory impairment in bvFTD and AD. Performance on episodic memory tasks and neuropsychological measures typically tapping into either DLPFC or VMPFC functions was assessed in 22 bvFTD, 32 AD patients and 35 age- and education-matched controls. Behaviourally, patient groups did not differ on measures of episodic memory recall or DLPFC-mediated executive functions. BvFTD patients were significantly more impaired on measures of VMPFC-mediated executive functions. Composite measures of the recall, DLPFC and VMPFC task scores were covaried against the T1 MRI scans of all participants to identify regions of atrophy correlating with performance on these tasks. Imaging analysis showed that impaired recall performance is associated with divergent patterns of PFC atrophy in bvFTD and AD. Whereas in bvFTD, PFC atrophy covariates for recall encompassed both DLPFC and VMPFC regions, only the DLPFC was implicated in AD. Our results suggest that episodic memory deficits in bvFTD and AD are underpinned by divergent prefrontal mechanisms. Moreover, we argue that these differences are not adequately captured by existing neuropsychological measures. PMID:24505314

  16. Individualized Theory of Mind (iToM): When Memory Modulates Empathy

    PubMed Central

    Ciaramelli, Elisa; Bernardi, Francesco; Moscovitch, Morris

    2013-01-01

    Functional neuroimaging studies have noted that brain regions supporting theory of mind (ToM) overlap remarkably with those underlying episodic memory, suggesting a link between the two processes. The present study shows that memory for others’ past experiences modulates significantly our appraisal of, and reaction to, what is happening to them currently. Participants read the life story of two characters; one had experienced a long series of love-related failures, the other a long series of work-related failures. In a later faux pas recognition task, participants reported more empathy for the character unlucky in love in love-related faux pas scenarios, and for the character unlucky at work in work-related faux pas scenarios. The memory-based modulation of empathy correlated with the number of details remembered from the characters’ life story. These results suggest that individuals use memory for other people’s past experiences to simulate how they feel in similar situations they are currently facing. The integration of ToM and memory processes allows adjusting mental state inferences to fit unique social targets, constructing an individualized ToM. PMID:23378839

  17. Subchronic glucocorticoid receptor inhibition rescues early episodic memory and synaptic plasticity deficits in a mouse model of Alzheimer's disease.

    PubMed

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

    2015-06-01

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

  18. Telomere Length and CCL11 Levels are Associated With Gray Matter Volume and Episodic Memory Performance in Schizophrenia: Evidence of Pathological Accelerated Aging.

    PubMed

    Czepielewski, Leticia Sanguinetti; Massuda, Raffael; Panizzutti, Bruna; Grun, Lucas Kich; Barbé-Tuana, Florencia María; Teixeira, Antonio Lucio; Barch, Deanna M; Gama, Clarissa S

    2017-02-22

    Schizophrenia (SZ) is associated with increased somatic morbidity and mortality, in addition to cognitive impairments similar to those seen in normal aging, which may suggest that pathological accelerated aging occurs in SZ. Therefore, we aim to evaluate the relationships of age, telomere length (TL), and CCL11 (aging and inflammatory biomarkers, respectively), gray matter (GM) volume and episodic memory performance in individuals with SZ compared to healthy controls (HC). One hundred twelve participants (48 SZ and 64 HC) underwent clinical and memory assessments, structural MRI, and had their peripheral blood drawn for biomarkers analysis. Comparisons of group means and correlations were performed. Participants with SZ had decreased TL and GM volume, increased CCL11, and worse memory performance compared to HC. In SZ, shorter TL was related to increased CCL11, and both biomarkers were related to reduced GM volume, all of which were related to worse memory performance. Older age was only associated with reduced GM, but longer duration of illness was related with all the aforementioned variables. Younger age of disease onset was associated with increased CCL11 levels and worse memory performance. In HC, there were no significant correlations except between memory and GM. Our results are consistent with the hypothesis of accelerated aging in SZ. These results may indicate that it is not age itself, but the impact of the disease associated with a pathological accelerated aging that leads to impaired outcomes in SZ.

  19. Neural mechanisms underlying the reward-related enhancement of motivation when remembering episodic memories with high difficulty.

    PubMed

    Shigemune, Yayoi; Tsukiura, Takashi; Nouchi, Rui; Kambara, Toshimune; Kawashima, Ryuta

    2017-04-04

    The motivation to receive rewards enhances episodic memories, and the motivation is modulated by task difficulty. In episodic retrieval, however, functional neuroimaging evidence regarding the motivation that mediates interactions between reward and task difficulty is scarce. The present fMRI study investigated this issue. During encoding performed without fMRI, participants encoded Japanese words using either deep or shallow strategies, which led to variation in difficulty level during subsequent retrieval. During retrieval with fMRI, participants recognized the target words in either high or low monetary reward conditions. In the behavioral results, a reward-related enhancement of memory was found only when the memory retrieval was difficult, and the rewarding effect on subjective motivation was greater in the retrieval of memories with high difficulty than those with low difficulty. The fMRI data showed that reward-related increases in the activation of the substantia nigra/ventral tegmental area (SN/VTA), medial temporal lobe (MTL), dorsomedial prefrontal cortex (dmPFC), and dorsolateral prefrontal cortex (dlPFC) were greater during the retrieval of memories with high difficulty than those with low difficulty. Furthermore, reward-related enhancement of functional connectivity between the SN/VTA and MTL and between the SN/VTA and dmPFC during the retrieval of memories with high difficulty was significantly correlated with reward-related increases of retrieval accuracy and subjective motivation. The reward-related enhancement of episodic retrieval and retrieval-related motivation could be most effective when the level of retrieval difficulty is optimized. Such reward-related enhancement of memory and motivation could be modulated by a network including the reward-related SN/VTA, motivation-related dmPFC, and memory-related MTL. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

  20. 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

    2017-04-07

    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.

  1. Dual origins of measured phase-amplitude coupling reveal distinct neural mechanisms underlying episodic memory in the human cortex.

    PubMed

    Vaz, Alex P; Yaffe, Robert B; Wittig, John H; Inati, Sara K; Zaghloul, Kareem A

    2017-03-01

    Phase-amplitude coupling (PAC) is hypothesized to coordinate neural activity, but its role in successful memory formation in the human cortex is unknown. Measures of PAC are difficult to interpret, however. Both increases and decreases in PAC have been linked to memory encoding, and PAC may arise due to different neural mechanisms. Here, we use a waveform analysis to examine PAC in the human cortex as participants with intracranial electrodes performed a paired associates memory task. We found that successful memory formation exhibited significant decreases in left temporal lobe and prefrontal cortical PAC, and these two regions exhibited changes in PAC within different frequency bands. Two underlying neural mechanisms, nested oscillations and sharp waveforms, were responsible for the changes in these regions. Our data therefore suggest that decreases in measured cortical PAC during episodic memory reflect two distinct underlying mechanisms that are anatomically segregated in the human brain.

  2. Memory Awareness for Faces in Individuals with Autism

    ERIC Educational Resources Information Center

    Wilkinson, Desiree A.; Best, Catherine A.; Minshew, Nancy J.; Strauss, Mark S.

    2010-01-01

    Little is known regarding metacognition in individuals with autism. Specifically, it is unclear how individuals with autism think about their own mental states. The current study assessed memory awareness during a facial recognition task. High-functioning children (M = 13.1 years, n = 18) and adults (M = 27.5 years, n = 16) with autism matched…

  3. Episodic memory and self-reference via semantic autobiographical memory: insights from an fMRI study in younger and older adults

    PubMed Central

    Kalenzaga, Sandrine; Sperduti, Marco; Anssens, Adèle; Martinelli, Penelope; Devauchelle, Anne-Dominique; Gallarda, Thierry; Delhommeau, Marion; Lion, Stéphanie; Amado, Isabelle; Krebs, Marie-Odile; Oppenheim, Catherine; Piolino, Pascale

    2015-01-01

    Self-referential processing relies mainly on the medial prefrontal cortex (MPFC) and enhances memory encoding (i.e., Self-Reference Effect, SRE) as it improves the accuracy and richness of remembering in both young and older adults. However, studies on age-related changes in the neural correlates of the SRE on the subjective (i.e., autonoetic consciousness) and the objective (i.e., source memory) qualitative features of episodic memory are lacking. In the present fMRI study, we compared the effects of a self-related (semantic autobiographical memory task) and a non self-related (general semantic memory task) encoding condition on subsequent episodic memory retrieval. We investigated encoding-related activity during each condition in two groups of 19 younger and 16 older adults. Behaviorally, the SRE improved subjective memory performance in both groups but objective memory only in young adults. At the neural level, a direct comparison between self-related and non self-related conditions revealed that SRE mainly activated the cortical midline system, especially the MPFC, in both groups. Additionally, in older adults and regardless of the condition, greater activity was found in a fronto-parietal network. Overall, correlations were noted between source memory performance and activity in the MPFC (irrespective of age) and visual areas (mediated by age). Thus, the present findings expand evidence of the role of the MPFC in self-referential processing in the context of source memory benefit in both young and older adults using incidental encoding via semantic autobiographical memory. However, our finding suggests that its role is less effective in aging. PMID:25628546

  4. A trade-off between local and distributed information processing associated with remote episodic versus semantic memory.

    PubMed

    Heisz, Jennifer J; Vakorin, Vasily; Ross, Bernhard; Levine, Brian; McIntosh, Anthony R

    2014-01-01

    Episodic memory and semantic memory produce very different subjective experiences yet rely on overlapping networks of brain regions for processing. Traditional approaches for characterizing functional brain networks emphasize static states of function and thus are blind to the dynamic information processing within and across brain regions. This study used information theoretic measures of entropy to quantify changes in the complexity of the brain's response as measured by magnetoencephalography while participants listened to audio recordings describing past personal episodic and general semantic events. Personal episodic recordings evoked richer subjective mnemonic experiences and more complex brain responses than general semantic recordings. Critically, we observed a trade-off between the relative contribution of local versus distributed entropy, such that personal episodic recordings produced relatively more local entropy whereas general semantic recordings produced relatively more distributed entropy. Changes in the relative contributions of local and distributed entropy to the total complexity of the system provides a potential mechanism that allows the same network of brain regions to represent cognitive information as either specific episodes or more general semantic knowledge.

  5. Stroop effects from newly learned color words: effects of memory consolidation and episodic context.

    PubMed

    Geukes, Sebastian; Gaskell, M Gareth; Zwitserlood, Pienie

    2015-01-01

    The Stroop task is an excellent tool to test whether reading a word automatically activates its associated meaning, and it has been widely used in mono- and bilingual contexts. Despite of its ubiquity, the task has not yet been employed to test the automaticity of recently established word-concept links in novel-word-learning studies, under strict experimental control of learning and testing conditions. In three experiments, we thus paired novel words with native language (German) color words via lexical association and subsequently tested these words in a manual version of the Stroop task. Two crucial findings emerged: When novel word Stroop trials appeared intermixed among native-word trials, the novel-word Stroop effect was observed immediately after the learning phase. If no native color words were present in a Stroop block, the novel-word Stroop effect only emerged 24 h later. These results suggest that the automatic availability of a novel word's meaning depends either on supportive context from the learning episode and/or on sufficient time for memory consolidation. We discuss how these results can be reconciled with the complementary learning systems account of word learning.

  6. The relationship between prospective memory and episodic future thinking in younger and older adulthood.

    PubMed

    Terrett, Gill; Rose, Nathan S; Henry, Julie D; Bailey, Phoebe E; Altgassen, Mareike; Phillips, Louise H; Kliegel, Matthias; Rendell, Peter G

    2016-01-01

    Episodic future thinking (EFT), the ability to project into the future to "preexperience" an event, and prospective memory (PM), remembering to perform an intended action, are both examples of future-oriented cognition. Recently it has been suggested that EFT might contribute to PM performance but to date few studies have examined the relationship between these two capacities. The aim of the present study was to investigate the nature and specificity of this relationship, as well as whether it varies with age. Participants were 125 younger and 125 older adults who completed measures of EFT and PM. Significant, positive correlations between EFT and PM were identified in both age groups. Furthermore, EFT ability accounted for significant unique variance in the young adults, suggesting that it may make a specific contribution to PM function. Within the older adult group, EFT did not uniquely contribute to PM, possibly indicating a reduced capacity to utilize EFT, or the use of compensatory strategies. This study is the first to provide systematic evidence for an association between variation in EFT and PM abilities in both younger and older adulthood and shows that the nature of this association varies as a function of age.

  7. Associations between basal cortisol levels and memory retrieval in healthy young individuals.

    PubMed

    Ackermann, Sandra; Hartmann, Francina; Papassotiropoulos, Andreas; de Quervain, Dominique J F; Rasch, Björn

    2013-11-01

    Cortisol is known to affect memory processes. On the one hand, stress-induced or pharmacologically induced elevations of cortisol levels enhance memory consolidation. On the other hand, such experimentally induced elevations of cortisol levels have been shown to impair memory retrieval. However, the effects of individual differences in basal cortisol levels on memory processes remain largely unknown. Here we tested whether individual differences in cortisol levels predict picture learning and recall in a large sample. A total of 1225 healthy young women and men viewed two different sets of emotional and neutral pictures on two consecutive days. Both sets were recalled after a short delay (10 min). On Day 2, the pictures seen on Day 1 were additionally recalled, resulting in a long-delay (20 hr) recall condition. Cortisol levels were measured three times on Days 1 and 2 via saliva samples before encoding, between encoding and recall as well as after recall testing. We show that stronger decreases in cortisol levels during retrieval testing were associated with better recall performance of pictures, regardless of emotional valence of the pictures or length of the retention interval (i.e., 10 min vs. 20 hr). In contrast, average cortisol levels during retrieval were not related to picture recall. Remarkably during encoding, individual differences in average cortisol levels as well as changes in cortisol did not predict memory recall. Our results support previous findings indicating that higher cortisol levels during retrieval testing hinders recall of episodic memories and extend this view onto interindividual changes in basal cortisol levels.

  8. Characteristics of prospective memory deficits in HIV-seropositive substance-dependent individuals: preliminary observations.

    PubMed

    Martin, Eileen M; Nixon, Heather; Pitrak, David L; Weddington, William; Rains, Niles A; Nunnally, Gerald; Grbesic, Silvana; Gonzalez, Raul; Jacobus, Joanna; Bechara, Antoine

    2007-07-01

    The construct of "prospective memory" (PM) refers to a type of episodic memory for a future intention or "remembering what one must do." This function has been proposed as a candidate mechanism underlying behaviors of critical importance in HIV disease, including adherence with medication regimens and continued engagement in risk behavior. We administered tasks of time-based and event-based prospective memory and control tasks of retrospective and working memory to 31 HIV-seropositive and 35 HIV-seronegative substance-dependent individuals (SDIs). We found that compared with HIV- controls HIV+ participants showed deficits in time-based but not event-based PM. Retrospective, but not working, memory performance correlated significantly with time-based PM performance. In addition, performance on the time-based PM task was a significant predictor of scores on a self-report measure of risky sexual and injection practices. These preliminary data provide new and unique findings regarding the components of executive function mediated by prefrontal cortical systems that are impaired among HIV+ SDIs and their relevance to "real-world" behaviors.

  9. Self-Imagining Enhances Recognition Memory in Memory-Impaired Individuals with Neurological Damage

    PubMed Central

    Grilli, Matthew D.; Glisky, Elizabeth L.

    2010-01-01

    Objective The ability to imagine an elaborative event from a personal perspective relies on a number of cognitive processes that may potentially enhance subsequent memory for the event, including visual imagery, semantic elaboration, emotional processing, and self-referential processing. In an effort to find a novel strategy for enhancing memory in memory-impaired individuals with neurological damage, the present study investigated the mnemonic benefit of a method we refer to as “self-imagining” – or the imagining of an event from a realistic, personal perspective. Method Fourteen individuals with neurologically-based memory deficits and fourteen healthy control participants intentionally encoded neutral and emotional sentences under three instructions: structural-baseline processing, semantic processing, and self-imagining. Results Findings revealed a robust “self-imagination effect” as self-imagination enhanced recognition memory relative to deep semantic elaboration in both memory-impaired individuals, F (1, 13) = 32.11, p < .001, η2 = .71, and healthy controls, F (1, 13) = 5.57, p < .05, η2 = .30. In addition, results indicated that mnemonic benefits of self-imagination were not limited by severity of the memory disorder nor were they related to self-reported vividness of visual imagery, semantic processing, or emotional content of the materials. Conclusions The findings suggest that the self-imagination effect may depend on unique mnemonic mechanisms possibly related to self-referential processing, and that imagining an event from a personal perspective makes that event particularly memorable even for those individuals with severe memory deficits. Self-imagining may thus provide an effective rehabilitation strategy for individuals with memory impairment. PMID:20873930

  10. "When did I learn and when shall I act?": The developmental relationship between episodic future thinking and memory.

    PubMed

    Naito, Mika; Suzuki, Toshiko

    2011-08-01

    This study investigated the development of the ability to reflect on one's personal past and future. A total of 64 4- to 6-year-olds received tasks of delayed self-recognition, source memory, delay of gratification, and a newly developed task of future-oriented action timing. Although children's performance on delayed self-recognition, source memory, and action timing improved with age, their performance on delay of gratification did not. Children's errors in source memory and action timing were solely and strongly associated with each other in older children (5-6years) even after controlling for age and verbal ability. Results are discussed in terms of mental time travel underlying episodic memory and future thinking that includes both the projection of oneself into the past and future and the appreciation of events' temporal relations.

  11. Uncinate fasciculus microstructure and verbal episodic memory in amyotrophic lateral sclerosis: a diffusion tensor imaging and neuropsychological study.

    PubMed

    Christidi, Foteini; Zalonis, Ioannis; Kyriazi, Stavroula; Rentzos, Michalis; Karavasilis, Efstratios; Wilde, Elisabeth A; Evdokimidis, Ioannis

    2014-12-01

    The present study evaluates the integrity of uncinate fasciculus (UF) and the association between UF microstructure and verbal episodic memory (as one of the cognitive functions linked to UF) in non-demented patients with amyotrophic lateral sclerosis (ALS) using diffusion tensor imaging (DTI). We studied 21 patients with ALS and 11 healthy, demographically-comparable volunteers. Fractional anisotropy, apparent diffusion coefficient, axial and radial diffusivity were the DTI metrics examined. Episodic memory was evaluated with Babcock Story Recall Test and Rey Auditory Verbal Learning Test (RAVLT) for patients; measures of immediate and delayed recall and retention for both tests and sum of words recalled through five learning trials for RAVLT were considered. Patients with ALS showed significant bilateral reduction of axial diffusivity in the UF as compared to controls. Furthermore, there were several significant relations between various DTI metrics (mostly in left hemisphere) and memory measures (specifically for the RAVLT). UF microstructural changes may contribute to ALS-related memory impairment, with word-list learning performance relying more upon the integrity of frontal and temporal connections than memory components associated with story recall.

  12. Difficulties in Working Memory Updating in Individuals with Intellectual Disability

    ERIC Educational Resources Information Center

    Carretti, B.; Belacchi, C.; Cornoldi, C.

    2010-01-01

    Background: Despite the critical role attributed to working memory (WM) updating for executive functions and fluid intelligence, no research has yet been carried out on its specific role in the vital case of fluid intelligence weakness, represented by individuals with intellectual disability (ID). Furthermore, the relationship between updating and…

  13. Individual Differences in Memory: Theory, Data, and Educational Implications

    ERIC Educational Resources Information Center

    Royer, James M.; And Others

    1978-01-01

    Individual differences in memory can be studied from two theoretical perspectives: Reappearance Theory or Constructive Theory. To test the Constructive Theory, two experiments examined the retention of high and low ability students. The results of both experiments supported the hypothesis that learners who acquire information rapidly also display…

  14. Abnormal insula functional network is associated with episodic memory decline in amnestic mild cognitive impairment.

    PubMed

    Xie, Chunming; Bai, Feng; Yu, Hui; Shi, Yongmei; Yuan, Yonggui; Chen, Gang; Li, Wenjun; Chen, Guangyu; Zhang, Zhijun; Li, Shi-Jiang

    2012-10-15

    dorsolateral prefrontal cortex, dorsomedial prefrontal cortex, and anterior temporal pole was found. Furthermore, the disrupted intrinsic connectivity was associated with episodic memory (EM) deficits in the aMCI patients and not in the CN subjects. These findings demonstrated that the functional integration of the insula networks plays an important role in the EM process. They provided new insight into the neural mechanism underlying the memory deficits in aMCI patients.

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

    PubMed Central

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

    2015-01-01

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

  16. Prefrontal dysconnectivity links to working memory deficit in first-episode schizophrenia.

    PubMed

    Fang, Xiaojing; Wang, Yulin; Cheng, Luqi; Zhang, Yuanchao; Zhou, Yuan; Wu, Shihao; Huang, Huan; Zou, Jilin; Chen, Cheng; Chen, Jun; Wang, Huiling; Jiang, Tianzi

    2017-03-13

    Working memory (WM) deficit is a core feature of schizophrenia and is characterized by abnormal functional integration in the prefrontal cortex, including the dorsolateral prefrontal cortex (dLPFC), dorsal anterior cingulate cortex (dACC), and ventrolateral prefrontal cortex (vLPFC). However, the specific mechanism by which the abnormal neuronal circuits that involve these brain regions contribute to this deficit is still unclear. Therefore, this study focused on these regions and sought to answer which abnormal causal relationships in these regions can be linked to impaired WM in schizophrenia. We used spectral dynamic causal modeling to estimate directed (effective) connectivity between these regions based on resting-state functional magnetic resonance imaging data from healthy control (HC) subjects and patients with first-episode schizophrenia (FES). By comparing these effective connections in the controls and patients, we found that the effective connectivity from the dACC to the dLPFC and from the right dLPFC to the left vLPFC was weaker in the FES group than in the HC group. Furthermore, these effective connections displayed a positive correlation with WM performance in the HCs. However, in the FES patients, the effective connectivity from the dACC to the dLPFC was not correlated with WM performance, and the effective connectivity from the right dLPFC to the left vLPFC was negatively correlated with WM performance. These results could be explained by an aberrant top-down mechanism of WM processing and provide new evidence for the dysconnectivity hypothesis of schizophrenia.

  17. Effects of Episodic Future Thinking and Self-Projection on Children's Prospective Memory Performance.

    PubMed

    Kretschmer-Trendowicz, Anett; Ellis, Judith A; Altgassen, Mareike

    2016-01-01

    The present study is the first to investigate the benefits of episodic future thinking (EFT) at encoding on prospective memory (PM) in preschool (age: M = 66.34 months, SD = 3.28) and primary school children (age: M = 88.36 months, SD = 3.12). A second aim was to examine if self-projection influences the possible effects of EFT instructions. PM was assessed using a standard PM paradigm in children with a picture-naming task as the ongoing activity in which the PM task was embedded. Further, two first- and two second-order ToM tasks were administered as indicator of children's self-projection abilities. Forty-one preschoolers and 39 school-aged children were recruited. Half of the participants in each age group were instructed to use EFT as a strategy to encode the PM task, while the others received standard PM instructions. Results revealed a significant age effect, with school-aged children significantly outperforming preschoolers and a significant effect of encoding condition with overall better performance when receiving EFT instructions compared to the standard encoding condition. Even though the interaction between age group and encoding condition was not significant, planned comparisons revealed first evidence that compared to the younger age group, older children's PM benefitted more from EFT instructions during intention encoding. Moreover, results showed that although self-projection had a significant impact on PM performance, it did not influence the effects of EFT instructions. Overall, results indicate that children can use EFT encoding strategies to improve their PM performance once EFT abilities are sufficiently developed. Further, they provide first evidence that in addition to executive functions, which have already been shown to influence the development of PM across childhood, self-projection seems to be another key mechanism underlying this development.

  18. Effects of Episodic Future Thinking and Self-Projection on Children’s Prospective Memory Performance

    PubMed Central

    Kretschmer-Trendowicz, Anett; Ellis, Judith A.; Altgassen, Mareike

    2016-01-01

    The present study is the first to investigate the benefits of episodic future thinking (EFT) at encoding on prospective memory (PM) in preschool (age: M = 66.34 months, SD = 3.28) and primary school children (age: M = 88.36 months, SD = 3.12). A second aim was to examine if self-projection influences the possible effects of EFT instructions. PM was assessed using a standard PM paradigm in children with a picture-naming task as the ongoing activity in which the PM task was embedded. Further, two first- and two second-order ToM tasks were administered as indicator of children’s self-projection abilities. Forty-one preschoolers and 39 school-aged children were recruited. Half of the participants in each age group were instructed to use EFT as a strategy to encode the PM task, while the others received standard PM instructions. Results revealed a significant age effect, with school-aged children significantly outperforming preschoolers and a significant effect of encoding condition with overall better performance when receiving EFT instructions compared to the standard encoding condition. Even though the interaction between age group and encoding condition was not significant, planned comparisons revealed first evidence that compared to the younger age group, older children’s PM benefitted more from EFT instructions during intention encoding. Moreover, results showed that although self-projection had a significant impact on PM performance, it did not influence the effects of EFT instructions. Overall, results indicate that children can use EFT encoding strategies to improve their PM performance once EFT abilities are sufficiently developed. Further, they provide first evidence that in addition to executive functions, which have already been shown to influence the development of PM across childhood, self-projection seems to be another key mechanism underlying this development. PMID:27355645

  19. Coding of Stimuli by Animals: Retrospection, Prospection, Episodic Memory and Future Planning

    ERIC Educational Resources Information Center

    Zentall, Thomas R.

    2010-01-01

    When animals code stimuli for later retrieval they can either code them in terms of the stimulus presented (as a retrospective memory) or in terms of the response or outcome anticipated (as a prospective memory). Although retrospective memory is typically assumed (as in the form of a memory trace), evidence of prospective coding has been found…

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

    PubMed Central

    Poth, Christian H.; Schneider, Werner X.

    2016-01-01

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

  1. Rapid Encoding of New Memories by Individual Neurons in the Human Brain.

    PubMed

    Ison, Matias J; Quian Quiroga, Rodrigo; Fried, Itzhak

    2015-07-01

    The creation of memories about real-life episodes requires rapid neuronal changes that may appear after a single occurrence of an event. How is such demand met by neurons in the medial temporal lobe (MTL), which plays a fundamental role in episodic memory formation? We recorded the activity of MTL neurons in neurosurgical patients while they learned new associations. Pairs of unrelated pictures, one of a person and another of a place, were used to construct a meaningful association modeling the episodic memory of meeting a person in a particular place. We found that a large proportion of responsive MTL neurons expanded their selectivity to encode these specific associations within a few trials: cells initially responsive to one picture started firing to the associated one but not to others. Our results provide a plausible neural substrate for the inception of associations, which are crucial for the formation of episodic memories.

  2. Rapid Encoding of New Memories by Individual Neurons in the Human Brain

    PubMed Central

    Ison, Matias J.; Quian Quiroga, Rodrigo; Fried, Itzhak

    2015-01-01

    Summary The creation of memories about real-life episodes requires rapid neuronal changes that may appear after a single occurrence of an event. How is such demand met by neurons in the medial temporal lobe (MTL), which plays a fundamental role in episodic memory formation? We recorded the activity of MTL neurons in neurosurgical patients while they learned new associations. Pairs of unrelated pictures, one of a person and another of a place, were used to construct a meaningful association modeling the episodic memory of meeting a person in a particular place. We found that a large proportion of responsive MTL neurons expanded their selectivity to encode these specific associations within a few trials: cells initially responsive to one picture started firing to the associated one but not to others. Our results provide a plausible neural substrate for the inception of associations, which are crucial for the formation of episodic memories. PMID:26139375

  3. Gray Matter Abnormalities in Temporal Lobe Epilepsy: Relationships with Resting-State Functional Connectivity and Episodic Memory Performance

    PubMed Central

    Doucet, Gaelle E.; He, Xiaosong; Sperling, Michael; Sharan, Ashwini; Tracy, Joseph I.

    2016-01-01

    Temporal lobe epilepsy (TLE) affects multiple brain regions through evidence from both structural (gray matter; GM) and functional connectivity (FC) studies. We tested whether these structural abnormalities were associated with FC abnormalities, and assessed the ability of these measures to explain episodic memory impairments in this population. A resting-state and T1 sequences were acquired on 94 (45 with mesial temporal pathology) TLE patients and 50 controls, using magnetic resonance imaging (MRI) technique. A voxel-based morphometry analysis was computed to determine the GM volume differences between groups (right, left TLE, controls). Resting-state FC between the abnormal GM volume regions was computed, and compared between groups. Finally, we investigated the relation between EM, GM and FC findings. Patients with and without temporal pathology were analyzed separately. The results revealed reduced GM volume in multiple regions in the patients relative to the controls. Using FC, we found the abnormal GM regions did not display abnormal functional connectivity. Lastly, we found in left TLE patients, verbal episodic memory was associated with abnormal left posterior hippocampus volume, while in right TLE, non-verbal episodic memory was better predicted by resting-state FC measures. This study investigated TLE abnormalities using a multi-modal approach combining GM, FC and neurocognitive measures. We did not find that the GM abnormalities were functionally or abnormally connected during an inter-ictal resting state, which may reflect a weak sensitivity of functional connectivity to the epileptic network. We provided evidence that verbal and non-verbal episodic memory in left and right TLE patients may have distinct relationships with structural and functional measures. Lastly, we provide data suggesting that in the setting of occult, non-lesional right TLE pathology, a coupling of structural and functional abnormalities in extra-temporal/non-ictal regions is

  4. Theta/gamma networks with slow NMDA channels learn sequences and encode episodic memory: role of NMDA channels in recall.

    PubMed

    Jensen, O; Lisman, J E

    1996-01-01

    This paper examines the role of slow N-methyl-D-aspartate (NMDA) channels (deactivation approximately 150 msec) in networks that multiplex different memories in different gamma subcycles of a low frequency theta oscillation. The NMDA channels are in the synapses of recurrent collaterals and govern synaptic modification in accord with known physiological properties. Because slow NMDA channels have a time constant that spans several gamma cycles, synaptic connections will form between cells that represent different memories. This enables brain structures that have slow NMDA channels to store heteroassociative sequence information in long-term memory. Recall of this stored sequence information can be initiated by presentation of initial elements of the sequence. The remaining sequence is then recalled at a rate of one memory every gamma cycle. A new role for the NMDA channel suggested by our finding is that recall at gamma frequency works well if slow NMDA channels provide the dominant component of the EPSP at the synapse of recurrent collaterals: The slow onset of these channels and their long duration allows the firing of one memory during one gamma cycle to trigger the next memory during the subsequent gamma cycle. An interesting feature of the readout mechanism is that the activation of a given memory is due to cumulative input from multiple previous memories in the stored sequence, not just the previous one. The network thus stores sequence information in a doubly redundant way: Activation of a memory depends on the strength of synaptic inputs from multiple cells of multiple previous memories. The cumulative property of sequence storage has support from the psychophysical literature. Cumulative learning also provides a solution to the disambiguation problem that occurs when different sequences have a region of overlap. In a final set of simulations, we show how coupling an autoassociative network to a heteroassociative network allows the storage of episodic

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

    PubMed

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

    2017-01-01

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

  6. NMDA Signaling in CA1 Mediates Selectively the Spatial Component of Episodic Memory

    ERIC Educational Resources Information Center

    Place, Ryan; Lykken, Christy; Beer, Zachery; Suh, Junghyup; McHugh, Thomas J.; Tonegawa, Susumu; Eichenbaum, Howard; Sauvage, Magdalena M.

    2012-01-01

    Recent studies focusing on the memory for temporal order have reported that CA1 plays a critical role in the memory for the sequences of events, in addition to its well-described role in spatial navigation. In contrast, CA3 was found to principally contribute to the memory for the association of items with spatial or contextual information in…

  7. 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.

  8. Hearing Loss Is Negatively Related to Episodic and Semantic Long-Term Memory but Not to Short-Term Memory

    ERIC Educational Resources Information Center

    Ronnberg, Jerker; Danielsson, Henrik; Rudner, Mary; Arlinger, Stig; Sternang, Ola; Wahlin, Ake; Nilsson, Lars-Goran

    2011-01-01

    Purpose: To test the relationship between degree of hearing loss and different memory systems in hearing aid users. Method: 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…

  9. Episodic Long-Term Memory of Spoken Discourse Masked by Speech: What Is the Role for Working Memory Capacity?

    ERIC Educational Resources Information Center

    Sorqvist, Patrik; Ronnberg, Jerker

    2012-01-01

    Purpose: To investigate whether working memory capacity (WMC) modulates the effects of to-be-ignored speech on the memory of materials conveyed by to-be-attended speech. Method: Two tasks (reading span, Daneman & Carpenter, 1980; Ronnberg et al., 2008; and size-comparison span, Sorqvist, Ljungberg, & Ljung, 2010) were used to measure individual…

  10. Evidence for the differential salience of disgust and fear in episodic memory.

    PubMed

    Chapman, Hanah A; Johannes, Kristen; Poppenk, Jordan L; Moscovitch, Morris; Anderson, Adam K

    2013-11-01

    Studies of emotional memory typically focus on the memory-enhancing effects of emotional dimensions such as arousal and valence. However, it is unclear to what extent different emotional categories could have distinct effects on memory over and above these dimensional influences. We tested this possibility by investigating the impact of two negative, highly arousing, and withdrawal-related emotions-disgust and fear--on attention and subsequent memory. To index differential attention during encoding, participants performed a speeded line discrimination task (LDT) while viewing disgusting and fearful photographs of similar valence and arousal, which were assessed for later memory. LDT performance was slower, and subsequent recall and recognition were greater, for disgusting compared to both fearful and neutral images. Disgust enhancement of memory remained significant even when controlling for attention at encoding and for arousal, visual salience, and conceptual distinctiveness. Receiver-operating curve analyses indicated that disgust enhancement of memory was due to increased sensitivity, rather than response bias. Thus, disgust appears to have a special salience in memory relative to certain other emotions, suggesting that a purely dimensional model of emotional influences on cognition is inadequate to account for their effects. We speculate that disgust enhancement of memory could arise from an origin in conditioned taste aversion, a highly enduring form of implicit memory.

  11. The Dorsolateral Prefrontal Cortex Plays a Role in Self-Initiated Elaborative Cognitive Processing during Episodic Memory Encoding: rTMS Evidence

    PubMed Central

    Hawco, Colin; Berlim, Marcelo T.; Lepage, Martin

    2013-01-01

    During episodic memory encoding, elaborative cognitive processing can improve later recall or recognition. While multiple studies examined the neural correlates of encoding strategies, few studies have explicitly focused on the self-initiation of elaborative encoding. Repetitive transcranial magnetic stimulation (rTMS), a method which can transiently disrupt neural activity, was administered during an associative encoding task. rTMS was either applied to the left dorsolateral prefrontal cortex (DLPFC) or to the vertex (a control region not involved in memory encoding) during presentation of pairs of words. Pairs could be semantically related or not related. Two encoding instructions were given, either cueing participants to analyze semantic relationships (cued condition), or to memorize the pair without any specific strategy cues (the self-initiated condition). Participants filled out a questionnaire regarding their use of memory strategies and performed a cued-recall task. We hypothesized that if the DLPFC plays a role in the self-initiation of elaborative encoding we would observe a reduction in memory performance in the self-initiated condition, particularly for related. We found a significant correlation between the effects of rTMS and strategy use, only in the self-initiated condition with related pairs. High strategy users showed reduced performance following DLPFC stimulation, while low strategy users tended to show increased recall following DLPFC stimulation during encoding. These results suggest the left DLPFC may be involved in the self-initiation of memory strategy use, and individuals may utilize different neural networks depending on their use of encoding strategies. PMID:24040072

  12. A case-control study of sex differences in strategic processing and episodic memory in obsessive-compulsive disorder.

    PubMed

    Segalàs, Cinto; Alonso, Pino; Labad, Javier; Real, Eva; Pertusa, Alberto; Jaurrieta, Nuria; Jiménez-Murcia, Susana; Menchón, José Manuel; Vallejo, Julio

    2010-01-01

    Although clinical and genetic data for obsessive-compulsive disorder (OCD) support the hypothesis of sexual dimorphism, the neuropsychological findings remain inconclusive. The aim of our study was to determine whether there are differences in cognitive performance between men and women with OCD as compared with healthy controls (HCs). A neuropsychological battery was administered to 50 patients with OCD (31 men and 19 women) and 50 HCs matched by sex, age, and educational level with patients. We evaluated intelligence, attention, episodic memory, and use of organizational strategies during encoding of verbal and nonverbal information. Male patients scored worse than controls did in measures of nonverbal memory tasks, whereas the cognitive performance of women with OCD was consistent with that of their HC counterparts. These results suggest a distinct pattern of cognitive dysfunction specific to the patients' sex.

  13. Differentiation and Response Bias in Episodic Memory: Evidence from Reaction Time Distributions

    ERIC Educational Resources Information Center

    Criss, Amy H.

    2010-01-01

    In differentiation models, the processes of encoding and retrieval produce an increase in the distribution of memory strength for targets and a decrease in the distribution of memory strength for foils as the amount of encoding increases. This produces an increase in the hit rate and decrease in the false-alarm rate for a strongly encoded compared…

  14. Recall of Remote Episodic Memories Can Appear Deficient because of a Gist-Based Retrieval Orientation

    ERIC Educational Resources Information Center

    Rudoy, John D.; Weintraub, Sandra; Paller, Ken A.

    2009-01-01

    Determining whether patients with amnesia can succeed in remembering their distant past has pivotal implications for theories of memory storage. However, various factors influence recall. We speculated that some patients with anterograde amnesia adopt a gist-based retrieval orientation for memories from all time periods, thereby exaggerating…

  15. Slow-Theta-to-Gamma Phase–Amplitude Coupling in Human Hippocampus Supports the Formation of New Episodic Memories

    PubMed Central

    Lega, Bradley; Burke, John; Jacobs, Joshua; Kahana, Michael J.

    2016-01-01

    Phase–amplitude coupling (PAC) has been proposed as a neural mechanism for coordinating information processing across brain regions. Here we sought to characterize PAC in the human hippocampus, and in temporal and frontal cortices, during the formation of new episodic memories. Intracranial recordings taken as 56 neurosurgical patients studied and recalled lists of words revealed significant hippocampal PAC, with slow-theta activity (2.5–5 Hz) modulating gamma band activity (34–130 Hz). Furthermore, a significant number of hippocampal electrodes exhibited greater PAC during successful than unsuccessful encoding, with the gamma activity at these sites coupled to the trough of the slow-theta oscillation. These same conditions facilitate LTP in animal models, providing a possible mechanism of action for this effect in human memory. Uniquely in the hippocampus, phase preference during item encoding exhibited a biphasic pattern. Overall, our findings help translate between the patterns identified during basic memory tasks in animals and those present during complex human memory encoding. We discuss the unique properties of human hippocampal PAC and how our findings relate to influential theories of information processing based on theta–gamma interactions. PMID:25316340

  16. Fornix as an imaging marker for episodic memory deficits in healthy aging and in various neurological disorders

    PubMed Central

    Douet, Vanessa; Chang, Linda

    2015-01-01

    The fornix is a part of the limbic system and constitutes the major efferent and afferent white matter tracts from the hippocampi. The underdevelopment of or injuries to the fornix are strongly associated with memory deficits. Its role in memory impairments was suggested long ago with cases of surgical forniceal transections. However, recent advances in brain imaging techniques, such as diffusion tensor imaging, have revealed that macrostructural and microstructural abnormalities of the fornix correlated highly with declarative and episodic memory performance. This structure appears to provide a robust and early imaging predictor for memory deficits not only in neurodegenerative and neuroinflammatory diseases, such as Alzheimer's disease and multiple sclerosis, but also in schizophrenia and psychiatric disorders, and during neurodevelopment and “typical” aging. The objective of the manuscript is to present a systematic review regarding published brain imaging research on the fornix, including the development of its tracts, its role in various neurological diseases, and its relationship to neurocognitive performance in human studies. PMID:25642186

  17. 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

    2016-05-27

    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.

  18. The effect of background music on episodic memory and autonomic responses: listening to emotionally touching music enhances facial memory capacity

    PubMed Central

    Mado Proverbio, C.A. Alice; Lozano Nasi, Valentina; Alessandra Arcari, Laura; De Benedetto, Francesco; Guardamagna, Matteo; Gazzola, Martina; Zani, Alberto

    2015-01-01

    The aim of this study was to investigate how background auditory processing can affect other perceptual and cognitive processes as a function of stimulus content, style and emotional nature. Previous studies have offered contrasting evidence, and it has been recently shown that listening to music negatively affected concurrent mental processing in the elderly but not in young adults. To further investigate this matter, the effect of listening to music vs. listening to the sound of rain or silence was examined by administering an old/new face memory task (involving 448 unknown faces) to a group of 54 non-musician university students. Heart rate and diastolic and systolic blood pressure were measured during an explicit face study session that was followed by a memory test. The results indicated that more efficient and faster recall of faces occurred under conditions of silence or when participants were listening to emotionally touching music. Whereas auditory background (e.g., rain or joyful music) interfered with memory encoding, listening to emotionally touching music improved memory and significantly increased heart rate. It is hypothesized that touching music is able to modify the visual perception of faces by binding facial properties with auditory and emotionally charged information (music), which may therefore result in deeper memory encoding. PMID:26469712

  19. The effect of background music on episodic memory and autonomic responses: listening to emotionally touching music enhances facial memory capacity.

    PubMed

    Proverbio, Alice Mado; Mado Proverbio, C A Alice; Lozano Nasi, Valentina; Alessandra Arcari, Laura; De Benedetto, Francesco; Guardamagna, Matteo; Gazzola, Martina; Zani, Alberto

    2015-10-15

    The aim of this study was to investigate how background auditory processing can affect other perceptual and cognitive processes as a function of stimulus content, style and emotional nature. Previous studies have offered contrasting evidence, and it has been recently shown that listening to music negatively affected concurrent mental processing in the elderly but not in young adults. To further investigate this matter, the effect of listening to music vs. listening to the sound of rain or silence was examined by administering an old/new face memory task (involving 448 unknown faces) to a group of 54 non-musician university students. Heart rate and diastolic and systolic blood pressure were measured during an explicit face study session that was followed by a memory test. The results indicated that more efficient and faster recall of faces occurred under conditions of silence or when participants were listening to emotionally touching music. Whereas auditory background (e.g., rain or joyful music) interfered with memory encoding, listening to emotionally touching music improved memory and significantly increased heart rate. It is hypothesized that touching music is able to modify the visual perception of faces by binding facial properties with auditory and emotionally charged information (music), which may therefore result in deeper memory encoding.

  20. Children's Binding of What-Where-When-"Who" in Episodic Memory: Identifying Oneself in the Past

    ERIC Educational Resources Information Center

    Burns, Patrick; Russell, James; Russell, Charlotte

    2016-01-01

    It is usually accepted that the binding of what, where, and when is a central component of young children's and animals' nonconceptual episodic abilities. We argue that additionally binding self-in-past (what-where-when-"who") adds a crucial conceptual requirement, and we ask when it becomes possible and what its cognitive correlates…

  1. Within-person Changes in Individual Symptoms of Depression Predict Subsequent Depressive Episodes in Adolescents: A Prospective Study

    PubMed Central

    Kouros, Chrystyna D.; Morris, Matthew C.; Garber, Judy

    2015-01-01

    The current longitudinal study examined which individual symptoms of depression uniquely predicted a subsequent Major Depressive Episode (MDE) in adolescents, and whether these relations differed by sex. Adolescents (N=240) were first interviewed in grade 6 (M=11.86 years old; SD = 0.56; 54% female; 81.5% Caucasian) and then annually through grade 12 regarding their individual symptoms of depression as well as the occurrence of MDEs. Individual symptoms of depression were assessed with the Children’s Depression Rating Scale-Revised (CDRS-R) and depressive episodes were assessed with the Longitudinal Interval Follow-up Evaluation (LIFE). Results showed that within-person changes in sleep problems and low self-esteem/excessive guilt positively predicted an increased likelihood of an MDE for both boys and girls. Significant sex differences also were found. Within-person changes in anhedonia predicted an increased likelihood of a subsequent MDE among boys, whereas irritability predicted a decreased likelihood of a future MDE among boys, and concentration difficulties predicted a decreased likelihood of an MDE in girls. These results identified individual depressive symptoms that predicted subsequent depressive episodes in male and female adolescents, and may be used to guide the early detection, treatment, and prevention of depressive disorders in youth. PMID:26105209

  2. Source Memory Rehabilitation: A Review Toward Recommendations for Setting Up a Strategy Training Aimed at the "What, Where, and When" of Episodic Retrieval.

    PubMed

    El Haj, Mohamad; Kessels, Roy P C; Allain, Philippe

    2016-01-01

    Source memory is a core component of episodic recall as it allows for the reconstruction of contextual details characterizing the acquisition of episodic events. Unlike episodic memory, little is known about source memory rehabilitation. Our review addresses this issue by emphasizing several strategies as useful tools in source memory rehabilitation programs. Four main strategies are likely to improve source recall in amnesic patients-namely, (a) contextual cueing, (b) unitization, (c) errorless learning, and (d) executive function programs. The rationale behind our suggestion is that: (a) reinstating contextual cues during retrieval can serve as retrieval cues and enhance source memory; (b) unitization as an encoding process allows for the integration of several pieces of contextual information into a new single entity; (c) errorless learning may prevent patients from making errors during source learning; and (d) as source memory deteriorations have been classically attributed to executive dysfunction, the rehabilitation of the latter ability is likely to maintain the former ability. Besides these four strategies, our review suggests several additional rehabilitation techniques such as the vanishing cues and spaced retrieval methods. Another additional strategy is the use of electronic devices. By gathering these strategies, our review provides a helpful guideline for clinicians dealing with source memory impairments. Our review further highlights the lack of randomized and controlled studies in the field of source memory rehabilitation.

  3. Impairments in Episodic-Autobiographical Memory and Emotional and Social Information Processing in CADASIL during Mid-Adulthood

    PubMed Central

    Staniloiu, Angelica; Woermann, Friedrich G.; Markowitsch, Hans J.

    2014-01-01

    Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) – is the most common genetic source of vascular dementia in adults, being caused by a mutation in NOTCH3 gene. Spontaneous de novo mutations may occur, but their frequency is largely unknown. Ischemic strokes and cognitive impairments are the most frequent manifestations, but seizures affect up to 10% of the patients. Herein, we describe a 47-year-old male scholar with a genetically confirmed diagnosis of CADASIL (Arg133Cys mutation in the NOTCH3 gene) and a seemingly negative family history of CADASIL illness, who was investigated with a comprehensive neuropsychological testing battery and neuroimaging methods. The patient demonstrated on one hand severe and accelerated deteriorations in multiple cognitive domains such as concentration, long-term memory (including the episodic-autobiographical memory domain), problem solving, cognitive flexibility and planning, affect recognition, discrimination and matching, and social cognition (theory of mind). Some of these impairments were even captured by abbreviated instruments for investigating suspicion of dementia. On the other hand the patient still possessed high crystallized (verbal) intelligence and a capacity to put forth a façade of well-preserved intellectual functioning. Although no definite conclusions can be drawn from a single case study, our findings point to the presence of additional cognitive changes in CADASIL in middle adulthood, in particular to impairments in the episodic-autobiographical memory domain and social information processing (e.g., social cognition). Whether these identified impairments are related to the patient’s specific phenotype or to an ascertainment bias (e.g., a paucity of studies investigating these cognitive functions) requires elucidation by larger scale research. PMID:25009481

  4. Brain regions involved in subprocesses of small-space episodic object-location memory: a systematic review of lesion and functional neuroimaging studies.

    PubMed

    Zimmermann, Kathrin; Eschen, Anne

    2017-04-01

    Object-location memory (OLM) enables us to keep track of the locations of objects in our environment. The neurocognitive model of OLM (Postma, A., Kessels, R. P. C., & Van Asselen, M. (2004). The neuropsychology of object-location memory. In G. L. Allen (Ed.), Human spatial memory: Remembering where (pp. 143-160). Mahwah, NJ: Lawrence Erlbaum, Postma, A., Kessels, R. P. C., & Van Asselen, M. (2008). How the brain remembers and forgets where things are: The neurocognition of object-location memory. Neuroscience & Biobehavioral Reviews, 32, 1339-1345. doi: 10.1016/j.neubiorev.2008.05.001 ) proposes that distinct brain regions are specialised for different subprocesses of OLM (object processing, location processing, and object-location binding; categorical and coordinate OLM; egocentric and allocentric OLM). It was based mainly on findings from lesion studies. However, recent episodic memory studies point to a contribution of additional or different brain regions to object and location processing within episodic OLM. To evaluate and update the neurocognitive model of OLM, we therefore conducted a systematic literature search for lesion as well as functional neuroimaging studies contrasting small-space episodic OLM with object memory or location memory. We identified 10 relevant lesion studies and 8 relevant functional neuroimaging studies. We could confirm some of the proposals of the neurocognitive model of OLM, but also differing hypotheses from episodic memory research, about which brain regions are involved in the different subprocesses of small-space episodic OLM. In addition, we were able to identify new brain regions as well as important research gaps.

  5. Fish oil and treadmill exercise have age-dependent effects on episodic memory and oxidative state of the hippocampus.

    PubMed

    Macêdo, Patrícia Fortes Cavalcanti de; de Melo, Janatar Stella Vasconcelos; Costa, Laís Alves Ribeiro; Braz, Glauber Rudá F; de Sousa, Shirley M; Lagranha, Cláudia J; Hornsby, Manuella Batista-de-Oliveira

    2017-01-09

    There is a growing interest to better understand how lifestyle choices can improve memory functions. Treadmill exercise and long-chain n-3 polyunsaturated fatty acids found in fish oil are able to stimulate hippocampal antioxidant defenses and improve memory. The aim was to test whether fish oil and exercise can improve rat's performance on memory tasks and optimize hippocampal antioxidant state in an age-dependent manner. Therefore, young and adult rats were exercised and received fish oil during 4 weeks. The exercise was performed for 30 min/day, with the speed gradually increasing from the first to the last week. Afterwards, episodic memory was measured by the recognition of object identity and spatial location. Hippocampal oxidative state was investigated with the levels of malondialdehyde (MDA), carbonyls content, antioxidant enzymatic activity (superoxide dismutase (SOD), catalase (CAT)), and antioxidant nonenzymatic activity (reduced glutathione, sulfhydryl content). The adult rats treated with fish oil and exercise (FO&EX) were able to recognize object's shape and placement; however, FO&EX young rats had impaired spatial recognition (p < 0.05). The FO&EX young rats did not have reduced MDA or carbonyl content, though either fish oil or exercise reduced MDA (p < 0.05) and carbonyl levels (p < 0.01). Exercise increased SOD (p < 0.001) and CAT activities (p < 0.05), and fish oil enhanced SOD activity (p < 0.05) in young rats. At adulthood, exercise increased MDA levels (p < 0.05), and FO&EX reduced MDA (p < 0.001). Finally, exercise and fish oil improved nonenzymatic antioxidant defense (p < 0.05) only in adult rats. Results support age-dependent effects of fish oil and exercise on memory and oxidative state of the hippocampus during either neurodevelopment or adulthood.

  6. Synchronous and Asynchronous Theta and Gamma Activity during Episodic Memory Formation

    PubMed Central

    Burke, John F.; Zaghloul, Kareem A.; Jacobs, Joshua; Williams, Ryan B.; Sperling, Michael R.; Sharan, Ashwini D.; Kahana, Michael J.

    2013-01-01

    To test the hypothesis that neural oscillations synchronize to mediate memory encoding, we analyzed electrocorticographic recordings taken as 68 human neurosurgical patients studied and subsequently recalled lists of common words. To the extent that changes in spectral power reflect synchronous oscillations, we would expect those power changes to be accompanied by increases in phase synchrony between the region of interest and neighboring brain areas. Contrary to the hypothesized role of synchronous gamma oscillations in memory formation, we found that many key regions that showed power increases during successful memory encoding also exhibited decreases in global synchrony. Similarly, cortical theta activity that decreases during memory encoding exhibits both increased and decreased global synchrony depending on region and stage of encoding. We suggest that network synchrony analyses, as used here, can help to distinguish between two major types of spectral modulations: (1) those that reflect synchronous engagement of regional neurons with neighboring brain areas, and (2) those that reflect either asynchronous modulations of neural activity or local synchrony accompanied by global disengagement from neighboring regions. We show that these two kinds of spectral modulations have distinct spatiotemporal profiles during memory encoding. PMID:23283342

  7. Comparison of semantic and episodic memory BOLD fMRI activation in predicting cognitive decline in older adults

    PubMed Central

    Hantke, Nathan; Nielson, Kristy A.; Woodard, John L.; Guidotti Breting, Leslie M.; Butts, Alissa; Seidenberg, Michael; Smith, J. Carson; Durgerian, Sally; Lancaster, Melissa; Matthews, Monica; Sugarman, Michael A.; Rao, Stephen M.

    2013-01-01

    Previous studies suggest that task-activated fMRI can predict future cognitive decline among healthy older adults. The present fMRI study examined the relative sensitivity of semantic memory (SM) versus episodic memory (EM) activation tasks for predicting cognitive decline. Seventy-eight cognitively intact elders underwent neuropsychological testing at entry and after an 18-month interval, with participants classified as cognitively “Stable” or “Declining” based on ≥1.0 SD decline in performance. Baseline fMRI scanning involved SM (famous name discrimination) and EM (name recognition) tasks. SM and EM fMRI activation, along with APOE ε4 status, served as predictors of cognitive outcome using a logistic regression analysis. Twenty-seven (34.6%) participants were classified as Declining and 51 (65.4%) as Stable. APOE ε4 status alone significantly predicted cognitive decline (R2 = .106; C index = .642). Addition of SM activation significantly improved prediction accuracy (R2 = .285; C index = .787), whereas the addition of EM did not (R2 = .212; C index = .711). In combination with APOE status, SM task activation predicts future cognitive decline better than EM activation. These results have implications for use of fMRI in prevention clinical trials involving the identification of persons at-risk for age-associated memory loss and Alzheimer’s disease. PMID:23199565

  8. The future is now: comparing the effect of episodic future thinking on impulsivity in lean and obese individuals.

    PubMed

    Daniel, Tinuke Oluyomi; Stanton, Christina M; Epstein, Leonard H

    2013-12-01

    The choice of small immediate rewards as opposed to larger delayed rewards, or delay discounting, is an important dimension of impulsive decision making. The inability to delay gratification is related to obesity, as well as other maladaptive behaviors such as substance abuse, problem drinking, smoking, pathological gambling, and risky HIV behaviors. One way to reduce delay discounting (DD) may be to use prospective imagery in the form of episodic future thinking (EFT) during inter-temporal decision making. We have recently shown that EFT reduces DD and ad libitum energy intake in obese individuals. However, no studies have examined whether the magnitude of the EFT effect differs between lean and overweight/obese individuals. We conducted a within-subject design experiment to compare the efficacy of EFT versus a control task in reducing DD between lean (N=24) and overweight/obese (N=24) women. Participants attended two sessions in which they engaged in either EFT or control episodic thinking during a DD task. We also examined whether individual differences such as trait time perspective, behavioral inhibition or behavioral activation moderated the EFT effect on DD. Results showed EFT reduced DD similarly for lean and overweight/obese individuals. The EFT effect was moderated by behavioral activation. This suggests EFT is just as effective in reducing impulsive decision making in obese individuals as it is in lean individuals and may be useful in reducing other impulsive obesity related behaviors.

  9. The future is now: Comparing the effect of episodic future thinking on impulsivity in lean and obese individuals

    PubMed Central

    Daniel, Tinuke Oluyomi; Stanton, Christina M.; Epstein, Leonard H.

    2014-01-01

    The choice of small immediate rewards as opposed to larger delayed rewards, or delay discounting, is an important dimension of impulsive decision making. The inability to delay gratification is related to obesity, as well as other maladaptive behaviors such as substance abuse, problem drinking, smoking, pathological gambling, and risky HIV behaviors. One way to reduce delay discounting (DD) may be to use prospective imagery in the form of episodic future thinking (EFT) during inter-temporal decision making. We have recently shown that EFT reduces DD and ad libitum energy intake in obese individuals. However, no studies have examined whether the magnitude of the EFT effect differs between lean and overweight/obese individuals. We conducted a within-subject design experiment to compare the efficacy of EFT versus a control task in reducing DD between lean (N = 24) and overweight/obese (N = 24) women. Participants attended two sessions in which they engaged in either EFT or control episodic thinking during a DD task. We also examined whether individual differences such as trait time perspective, behavioral inhibition or behavioral activation moderated the EFT effect on DD. Results showed EFT reduced DD similarly for lean and overweight/obese individuals. The EFT effect was moderated by behavioral activation. This suggests EFT is just as effective in reducing impulsive decision making in obese individuals as it is in lean individuals and may be useful in reducing other impulsive obesity related behaviors. PMID:23917063

  10. Dissociable mechanisms underlying individual differences in visual working memory capacity.

    PubMed

    Gulbinaite, Rasa; Johnson, Addie; de Jong, Ritske; Morey, Candice C; van Rijn, Hedderik

    2014-10-01

    Individuals scoring relatively high on measures of working memory tend to be more proficient at controlling attention to minimize the effect of distracting information. It is currently unknown whether such superior attention control abilities are mediated by stronger suppression of irrelevant information, enhancement of relevant information, or both. Here we used steady-state visual evoked potentials (SSVEPs) with the Eriksen flanker task to track simultaneously the attention to relevant and irrelevant information by tagging target and distractors with different frequencies. This design allowed us to dissociate attentional biasing of perceptual processing (via SSVEPs) and stimulus processing in the frontal cognitive control network (via time-frequency analyses of EEG data). We show that while preparing for the upcoming stimulus, high- and low-WMC individuals use different strategies: High-WMC individuals show attentional suppression of the irrelevant stimuli, whereas low-WMC individuals demonstrate attentional enhancement of the relevant stimuli. Moreover, behavioral performance was predicted by trial-to-trial fluctuations in strength of distractor-suppression for high-WMC participants. We found no evidence for WMC-related differences in cognitive control network functioning, as measured by midfrontal theta-band power. Taken together, these findings suggest that early suppression of irrelevant information is a key underlying neural mechanism by which superior attention control abilities are implemented.

  11. Impact of Sex and Menopausal Status on Episodic Memory Circuitry in Early Midlife

    PubMed Central

    Weiss, Blair K.; Makris, Nikos; Whitfield-Gabrieli, Sue; Buka, Stephen L.; Klibanski, Anne

    2016-01-01

    Cognitive neuroscience of aging studies traditionally target participants age 65 and older. However, epidemiological surveys show that many women report increased forgetfulness earlier in the aging process, as they transition to menopause. In this population-based fMRI study, we stepped back by over a decade to characterize the changes in memory circuitry that occur in early midlife, as a function of sex and women's reproductive stage. Participants (N = 200; age range, 45–55) performed a verbal encoding task during fMRI scanning. Reproductive histories and serologic evaluations were used to determine menopausal status. Results revealed a pronounced impact of reproductive stage on task-evoked hippocampal responses, despite minimal difference in chronological age. Next, we examined the impact of sex and reproductive stage on functional connectivity across task-related brain regions. Postmenopausal women showed enhanced bilateral hippocampal connectivity relative to premenopausal and perimenopausal women. Across women, lower 17β-estradiol concentrations were related to more pronounced alterations in hippocampal connectivity and poorer performance on a subsequent memory retrieval task, strongly implicating sex steroids in the regulation of this circuitry. Finally, subgroup analyses revealed that high-performing postmenopausal women (relative to low and middle performers) exhibited a pattern of brain activity akin to premenopausal women. Together, these findings underscore the importance of considering reproductive stage, not simply chronological age, to identify neuronal and cognitive changes that unfold in the middle decades of life. In keeping with preclinical studies, these human findings suggest that the decline in ovarian estradiol production during menopause plays a significant role in shaping memory circuitry. SIGNIFICANCE STATEMENT Maintaining intact memory function with age is one of the greatest public health challenges of our time, and women have an

  12. Cognitive Association Formation in Episodic Memory: Evidence from Event-Related Potentials

    ERIC Educational Resources Information Center

    Kim, Alice S. N.; Vallesi, Antonino; Picton, Terence W.; Tulving, Endel

    2009-01-01

    The present study focused on the processes underlying cognitive association formation by investigating subsequent memory effects. Event-related potentials were recorded as participants studied pairs of words, presented one word at a time, for later recall. The findings showed that a frontal-positive late wave (LW), which occurred 1-1.6 s after the…

  13. Tactile short-term memory in sensory-deprived individuals.

    PubMed

    Papagno, Costanza; Minniti, Giovanna; Mattavelli, Giulia C; Mantovan, Lara; Cecchetto, Carlo

    2017-02-01

    To verify whether loosing a sense or two has consequences on a spared sensory modality, namely touch, and whether these consequences depend on practice or are biologically determined, we investigated 13 deafblind participants, 16 deaf participants, 15 blind participants, and 13 matched normally sighted and hearing controls on a tactile short-term memory task, using checkerboard matrices of increasing length in which half of the squares were made up of a rough texture and half of a smooth one. Time of execution of a fixed matrix, number of correctly reproduced matrices, largest matrix correctly reproduced and tactile span were recorded. The three groups of sensory-deprived individuals did not differ in any measure, while blind and deaf participants outscored controls in all parameters except time of execution; the difference approached significance for deafblind people compared to controls only in one measure, namely correctly reproduced matrices. In blind and deafblind participants, performance negatively correlated with age of Braille acquisition, the older being the subject when acquiring Braille, the lower the performance, suggesting that practice plays a role. However, the fact that deaf participants, who did not share tactile experience, performed similarly to blind participants and significantly better than controls highlights that practice cannot be the only contribution to better tactile memory.

  14. Individual Differences in Memory Search and Their Relation to Intelligence

    PubMed Central

    Healey, M. Karl; Crutchley, Patrick; Kahana, Michael J.

    2014-01-01

    Attempts to understand why memory predicts intelligence have not fully leveraged state-of-the-art measures of recall dynamics. Using data from a multi–session free recall study we examine individual differences in measures of recall initiation and post–initiation transitions. We identify four sources of variation: a recency factor reflecting variation in the tendency to initiate recall from an item near the end of the list, a primacy factor reflecting a tendency to initiate from the beginning of the list, a temporal factor corresponding to transitions mediated by temporal associations, and a semantic factor corresponding to semantically–mediated transitions. Together these four factors account for 83% of the variability in overall recall accuracy, suggesting they provide a nearly complete picture of recall dynamics. We also show that these sources of variability account for over 80% of the variance shared between memory and intelligence. The temporal association factor was the most influential in predicting both recall accuracy and intelligence. We outline a theory of how controlled drift of temporal context may be critical across a range of cognitive activities. PMID:24730719

  15. Collaboration can improve individual recognition memory: evidence from immediate and delayed tests.

    PubMed

    Rajaram, Suparna; Pereira-Pasarin, Luciane P

    2007-02-01

    In two experiments, we tested the effects of collaboration on individual recognition memory. In Experiment 1, participants studied pictures and words either for meaning or for surface properties and made recognition memory judgments individually either following group discussion among 3 members (collaborative condition) or in the absence of discussion (noncollaborative condition). Levels of processing and picture superiority effects were replicated, and collaboration significantly increased individual recognition memory. Experiment 2 replicated this positive effect and showed that even though memory sensitivity declined at longer delays (48 h and 1 week), collaboration continued to exert a positive influence. These findings show that (1) consensus is not necessary for producing benefits of collaboration on individual recognition, (2) collaborative facilitation on individual memory is robust, and (3) collaboration enhances individual memory further if conditions predispose individual accuracy in the absence of collaboration.

  16. Auditory working memory predicts individual differences in absolute pitch learning.

    PubMed

    Van Hedger, Stephen C; Heald, Shannon L M; Koch, Rachelle; Nusbaum, Howard C

    2015-07-01

    Absolute pitch (AP) is typically defined as the ability to label an isolated tone as a musical note in the absence of a reference tone. At first glance the acquisition of AP note categories seems like a perceptual learning task, since individuals must assign a category label to a stimulus based on a single perceptual dimension (pitch) while ignoring other perceptual dimensions (e.g., loudness, octave, instrument). AP, however, is rarely discussed in terms of domain-general perceptual learning mechanisms. This is because AP is typically assumed to depend on a critical period of development, in which early exposure to pitches and musical labels is thought to be necessary for the development of AP precluding the possibility of adult acquisition of AP. Despite this view of AP, several previous studies have found evidence that absolute pitch category learning is, to an extent, trainable in a post-critical period adult population, even if the performance typically achieved by this population is below the performance of a "true" AP possessor. The current studies attempt to understand the individual differences in learning to categorize notes using absolute pitch cues by testing a specific prediction regarding cognitive capacity related to categorization - to what extent does an individual's general auditory working memory capacity (WMC) predict the success of absolute pitch category acquisition. Since WMC has been shown to predict performance on a wide variety of other perceptual and category learning tasks, we predict that individuals with higher WMC should be better at learning absolute pitch note categories than individuals with lower WMC. Across two studies, we demonstrate that auditory WMC predicts the efficacy of learning absolute pitch note categories. These results suggest that a higher general auditory WMC might underlie the formation of absolute pitch categories for post-critical period adults. Implications for understanding the mechanisms that underlie the

  17. Human intracranial high-frequency activity maps episodic memory formation in space and time

    PubMed Central

    Burke, John F.; Long, Nicole M.; Zaghloul, Kareem A.; Sharan, Ashwini D.; Sperling, Michael R.; Kahana, Michael J.

    2013-01-01

    Noninvasive neuroimaging studies have revealed a network of brain regions that activate during human memory encoding; however, the relative timing of such activations remains unknown. Here we used intracranially recorded high-frequency activity (HFA) to first identify regions that activate during successful encoding. Then, we leveraged the high-temporal precision of HFA to investigate the timing of such activations. We found that memory encoding invokes two spatiotemporally distinct activations: early increases in HFA that involve the ventral visual pathway as well as the medial temporal lobe and late increases in HFA that involve the left inferior frontal gyrus, left posterior parietal cortex and left ventrolateral temporal cortex. We speculate that these activations reflect higher-order visual processing and top-down modulation of attention/semantic information, respectively. PMID:23827329

  18. Factors Affecting Two Types of Memory Specificity: Particularization of Episodes and Details

    PubMed Central

    Granhag, Pär Anders; Strömwall, Leif A.

    2016-01-01

    Memory for repeated events is relevant to legal investigations about repeated occurrences. We investigated how two measures of specificity (number of events referred to and amount of detail reported about the events) were influenced by interviewees’ age, number of experienced events, interviewer, perceived unpleasantness, and memory rehearsal. Transcribed narratives consisting of over 40.000 utterances from 95 dental patients, and the corresponding dental records, were studied. Amount of detail was measured by categorizing the utterances as generic, specific, or specific-extended. We found that the two measures were affected differently by all five factors. For instance, number of experienced events positively influenced number of referred events but had no effect on amount of detail provided about the events. We make suggestions for future research and encourage reanalysis of the present data set and reuse of the material. PMID:27851775

  19. Getting a Grip on Memory: Unilateral Hand Clenching Alters Episodic Recall

    DTIC Science & Technology

    2013-04-24

    Electroencephalographic ( EEG ) measures demonstrate that a mere 90 seconds of left hand clenching increases right hemisphere activity, and similar right...However, to our knowledge no research has examined cognition , and in particular memory processing, as a function of hemispheric activation induced via...contraction of hand muscles. Cortex 30: 247–254. 5. Davidson RJ (2002) Anxiety and affective style : Role of prefrontal cortex and amygdala. Biol Psychiatry

  20. Metacognitive profiles in individuals with a first episode of psychosis and their relation to social functioning and perceived social support.

    PubMed

    Massé, Marjolaine; Lecomte, Tania

    2015-08-01

    Poorer metacognitive abilities are recognized as strong predictors of social functioning deficits in individuals with schizophrenia, but have not been studied in relation to perceived social support. Furthermore, traditional measures of metacognition fail to consider ecological aspects such as the interaction between thinking of one's own or other's mind, and mastery. As a constellation, these abilities may influence domains of social functioning and perceived social support differently. Therefore, this study aimed to establish whether distinct metacognitive profiles exist within a population of individuals with a first psychotic episode, and to determine how such profiles influence individual domains of social functioning and perceived social support. Participants (n=50) were recruited from two early psychosis outpatient clinics in Montreal, Canada. Demographic information, social functioning and perceived social support were measured using self-reported questionnaires, and metacognition was scored from the transcripts of a semi-structured interview designed to avoid leading responses. Cluster analysis revealed three distinct metacognitive profiles: (1) overall better abilities; (2) poor abilities on thinking of one's own and other's mind, but better mastery; and (3) overall poorer abilities. Analyses showed significant differences between profiles only for self-reported intimacy and independent living abilities, with the second profile showing better abilities than the third. Profiles did not simply represent consistently higher or lower functioning across subscales. Although mastery was predictive of social functioning, the ability to think in an increasingly complex manner of one's self and others did not seem to improve functioning in individuals with a first episode of psychosis.

  1. Hippocampal sharp wave‐ripple: A cognitive biomarker for episodic memory and planning

    PubMed Central

    2015-01-01

    ABSTRACT Sharp wave ripples (SPW‐Rs) represent the most synchronous population pattern in the mammalian brain. Their excitatory output affects a wide area of the cortex and several subcortical nuclei. SPW‐Rs occur during “off‐line” states of the brain, associated with consummatory behaviors and non‐REM sleep, and are influenced by numerous neurotransmitters and neuromodulators. They arise from the excitatory recurrent system of the CA3 region and the SPW‐induced excitation brings about a fast network oscillation (ripple) in CA1. The spike content of SPW‐Rs is temporally and spatially coordinated by a consortium of interneurons to replay fragments of waking neuronal sequences in a compressed format. SPW‐Rs assist in transferring this compressed hippocampal representation to distributed circuits to support memory consolidation; selective disruption of SPW‐Rs interferes with memory. Recently acquired and pre‐existing information are combined during SPW‐R replay to influence decisions, plan actions and, potentially, allow for creative thoughts. In addition to the widely studied contribution to memory, SPW‐Rs may also affect endocrine function via activation of hypothalamic circuits. Alteration of the physiological mechanisms supporting SPW‐Rs leads to their pathological conversion, “p‐ripples,” which are a marker of epileptogenic tissue and can be observed in rodent models of schizophrenia and Alzheimer's Disease. Mechanisms for SPW‐R genesis and function are discussed in this review. © 2015 The Authors Hippocampus Published by Wiley Periodicals, Inc. PMID:26135716

  2. Hippocampal sharp wave-ripple: A cognitive biomarker for episodic memory and planning.

    PubMed

    Buzsáki, György

    2015-10-01

    Sharp wave ripples (SPW-Rs) represent the most synchronous population pattern in the mammalian brain. Their excitatory output affects a wide area of the cortex and several subcortical nuclei. SPW-Rs occur during "off-line" states of the brain, associated with consummatory behaviors and non-REM sleep, and are influenced by numerous neurotransmitters and neuromodulators. They arise from the excitatory recurrent system of the CA3 region and the SPW-induced excitation brings about a fast network oscillation (ripple) in CA1. The spike content of SPW-Rs is temporally and spatially coordinated by a consortium of interneurons to replay fragments of waking neuronal sequences in a compressed format. SPW-Rs assist in transferring this compressed hippocampal representation to distributed circuits to support memory consolidation; selective disruption of SPW-Rs interferes with memory. Recently acquired and pre-existing information are combined during SPW-R replay to influence decisions, plan actions and, potentially, allow for creative thoughts. In addition to the widely studied contribution to memory, SPW-Rs may also affect endocrine function via activation of hypothalamic circuits. Alteration of the physiological mechanisms supporting SPW-Rs leads to their pathological conversion, "p-ripples," which are a marker of epileptogenic tissue and can be observed in rodent models of schizophrenia and Alzheimer's Disease. Mechanisms for SPW-R genesis and function are discussed in this review.

  3. Knowing what from where: Hippocampal connectivity with temporoparietal cortex at rest is linked to individual differences in semantic and topographic memory.

    PubMed

    Sormaz, Mladen; Jefferies, Elizabeth; Bernhardt, Boris C; Karapanagiotidis, Theodoros; Mollo, Giovanna; Bernasconi, Neda; Bernasconi, Andrea; Hartley, Tom; Smallwood, Jonathan

    2017-02-28

    The hippocampus contributes to episodic, spatial and semantic aspects of memory, yet individual differences within and between these functions are not well-understood. In 136 healthy individuals, we investigated whether these differences reflect variation in the strength of connections between functionally-specialised segments of the hippocampus and diverse cortical regions that participate in different aspects of memory. Better topographical memory was associated with stronger connectivity between lingual gyrus and left anterior, rather than posterior, hippocampus. Better semantic memory was associated with increased connectivity between the intracalcarine/cuneus and left, rather than right, posterior hippocampus. Notably, we observed a double dissociation between semantic and topographical memory: better semantic memory was associated with stronger connectivity between left temporoparietal cortex and left anterior hippocampus, while better topographic memory was linked to stronger connectivity with right anterior hippocampus. Together these data support a division-of-labour account of hippocampal functioning: at the population level, differences in connectivity across the hippocampus reflect functional specialisation for different facets of memory, while variation in these connectivity patterns across individuals is associated with differences in the capacity to retrieve different types of information. In particular, within-hemisphere connectivity between hippocampus and left temporoparietal cortex supports conceptual processing at the expense of spatial ability.

  4. Overgeneral autobiographical memory at baseline predicts depressive symptoms at follow-up in patients with first-episode depression.

    PubMed

    Liu, Yansong; Zhang, Fuquan; Wang, Zhiqiang; Cao, Leiming; Wang, Jun; Na, Aiguo; Sun, Yujun; Zhao, Xudong

    2016-09-30

    Previous studies have shown that overgeneral autobiographical memory (OGM) is a characteristic of depression. However, there are no studies to explore the association between baseline OGM and depressive symptoms at follow-up in patients with first-episode depression (FE). This study investigated whether baseline OGM predicts depressive symptoms at follow-up in patients with FE. We recruited 125 patients with FE. The participants were divided into remitted group and non-remitted group according to the severity of their depression at 12 months follow-up. The measures consisted of the 17-item Hamilton Depression Rating Scale, Ruminative Response Scale, and Autobiographical Memory Test. Hierarchical linear regression analyses and bootstrap mediation analyses were conducted. The results showed that non-remitted patients had more OGM at baseline. Baseline OGM predicted depressive symptoms at follow-up in patients with FE. Rumination mediated the relationship between baseline OGM and depressive symptoms at follow-up. Our findings highlight OGM as a vulnerability factor involved in the maintenance of depression in patients with FE.

  5. How Do the Different Components of Episodic Memory Develop? Role of Executive Functions and Short-Term Feature-Binding Abilities

    ERIC Educational Resources Information Center

    Picard, Laurence; Cousin, Sidonie; Guillery-Girard, Berenere; Eustache, Francis; Piolino, Pascale

    2012-01-01

    This study investigated the development of all 3 components of episodic memory (EM), as defined by Tulving, namely, core factual content, spatial context, and temporal context. To this end, a novel, ecologically valid test was administered to 109 participants aged 4-16 years. Results showed that each EM component develops at a different rate.…

  6. Older individuals with HIV infection have greater memory deficits than younger individuals

    PubMed Central

    Tan, IL; Smith, BR; Hammond, E; Vronbrock-Roosa, H; Creighton, JA; Selnes, OA; McArthur, JC; Sacktor, N

    2013-01-01

    Objectives The prevalence of HIV-associated neurocognitive disorder (HAND) remains persistently high in the era of combination anti-retroviral therapy (cART). We aimed to characterize the pattern of neurocognitive dysfunction in older subjects with HAND, in particular amnestic versus non-amnestic impairment. Methods 106 subjects from the Johns Hopkins University NIMH Clinical Outcomes cohort underwent standardized neuropsychological (NP) testing between November 2006 and June 2010. We examined performance in seven cognitive domains (memory, attention, speed of processing, visuospatial, language, motor and executive). Older subjects were defined as age > 50 years at the time of NP testing. Subjects were diagnosed with HAND according to established criteria, and dichotomized into amnestic cognitive impairment or non-amnestic cognitive impairment, with deficit defined as z-scores < −1.5 for the verbal and non-verbal memory domains. Results There were 32 older subjects with a mean age (SD) of 54.2 (2.8) years, and 74 younger subjects, 43.7 (4.3) years. Older age was associated with a 4.8 fold higher odds of memory deficits, adjusted for potential confounders (p=0.035) identified a priori. With age modeled as a continuous covariate, every 1-year increase in age was associated with a 1.11 fold higher odds of memory deficit (p=0.05). Conclusion There was a higher proportion of amnestic cognitive impairment among older subjects than younger subjects with HIV infection. Neurodegenerative processes other than those directly due to HIV may be increasingly important as individuals with chronic HIV infection and HAND survive into older age. PMID:24078559

  7. White Matter Integrity in Genetic High-Risk Individuals and First-Episode Schizophrenia Patients: Similarities and Disassociations

    PubMed Central

    Zhou, Yifang; Liu, Jie; Driesen, Naomi; Womer, Fay; Chen, Kaiyuan; Wang, Ye; Jiang, Xiaowei; Zhou, Qian; Bai, Chuan; Wang, Dahai

    2017-01-01

    White matter (WM) neuroimaging studies have shown varied findings at different stages of schizophrenia (SZ). Understanding these variations may elucidate distinct markers of genetic vulnerability and conversion to psychosis. To examine the similarities and differences in WM connectivity between those at-risk for and in early stages of SZ, a cross-sectional diffusion tensor imaging study of 48 individuals diagnosed with first-episode SZ (FE-SZ), 37 nonpsychotic individuals at a high genetic risk of SZ (GHR-SZ), and 67 healthy controls (HC) was conducted. Decreased fractional anisotropy (FA) in the corpus callosum (CC), anterior cingulum (AC), and uncinate fasciculus (UF) was observed in both the GHR-SZ and FE-SZ groups, while decreased FAs in the superior longitudinal fasciculus (SLF) and the fornix were only seen in the FE-SZ participants. Additionally, both GHR-SZ and FE-SZ showed worse executive performance than HC. The left SLF III FA was significantly positively correlated with hallucinations, and right SLF II was positively correlated with thought disorder. The presence of shared WM deficits in both FE-SZ and GHR-SZ individuals may reflect the genetic liability to SZ, while the disparate FA changes in the FE-SZ group may represent symptom-generating circuitry that mediates perceptual and cognitive disturbances of SZ and ultimately culminates in the onset of psychotic episodes.

  8. Feeling-of-knowing in episodic memory in patients with Parkinson's disease with various motor symptoms.

    PubMed

    Yu, Rwei-Ling; Wu, Ruey-Meei; Tai, Chun-Hwei; Lin, Chin-Hsien; Hua, Mau-Sun

    2010-06-15

    The aim of this study was to examine metamemory in patients with Parkinson's disease (PD) with different dominant motor symptoms. This is a prospective case-control study. Fifty-five PD patients [25 patients with tremor-dominant (TD) motor symptoms and 30 patients with akinetic and rigidity-dominant (ARD) motor symptoms] and 30 normal controls were studied. The two patient groups were similar in terms of age, level of education, disease duration, and disease severity. Metamemory was measured using the experimental metamemory task [feeling-of-knowing (FOK) paradigm]. In addition, memory and executive functions were determined using detailed cognitive tests. In comparison with normal subjects and TD patients, ARD patients exhibited impaired FOK accuracy (P = 0.007). Furthermore, correlation analysis revealed an intergroup differential pattern, which indicated that FOK accuracy was primarily related to memory ability in ARD patients and executive function in TD patients. Our results provide evidence of impaired metamemory in the early stages of PD with ARD rather than TD motor symptoms. These findings might be useful for designing specific medical care strategies for ARD patients. Further studies are needed to determine whether impaired metamemory is an early predictor for brain alteration in PD patients.

  9. A neoHebbian framework for episodic memory; role of dopamine-dependent late LTP

    PubMed Central

    Grace, Anthony A.; Duzel, Emrah

    2011-01-01

    According to the Hebb rule, the change in the strength of a synapse depends only on the local interaction of presynaptic and postsynaptic events. Studies at many types of synapses indicate that the early phase of long-term potentiation (LTP) has Hebbian properties. However, it is now clear that the Hebb rule does not account for late LTP; this requires an additional signal that is non-local. For novel information and motivational events such as rewards, this signal at hippocampal CA1 synapses is mediated by the neuromodulator, dopamine. In this Review, we discuss recent experimental findings that support the view that this “neoHebbian” framework can account for memory behavior in a variety of learning situations. PMID:21851992

  10. The slow forgetting of emotional episodic memories: An emotional binding account

    PubMed Central

    Yonelinas, Andrew P.; Ritchey, Maureen

    2015-01-01

    Emotional events are remembered better than neutral events, and this emotion advantage becomes particularly pronounced over time. The time dependent effects of emotion impact recollection rather than familiarity-based recognition, and they influence recollection of item-specific details rather than contextual details. Moreover, the amygdala, but not the hippocampus, is critical in producing these effects. Time-dependent effects of emotion have been attributed to an emotional consolidation process whereby the amygdala gradually facilitates the storage of emotional memories by other medial temporal lobe regions. However, here we propose that these effects can be better understood by an emotional binding account whereby the amygdala mediates the recollection of item-emotion bindings that are forgotten more slowly than item-context bindings supported by the hippocampus. PMID:25836045

  11. Predicting episodic memory performance using different biomarkers: results from Argentina-Alzheimer’s Disease Neuroimaging Initiative

    PubMed Central

    Russo, María Julieta; Cohen, Gabriela; Chrem Mendez, Patricio; Campos, Jorge; Nahas, Federico E; Surace, Ezequiel I; Vazquez, Silvia; Gustafson, Deborah; Guinjoan, Salvador; Allegri, Ricardo F; Sevlever, Gustavo

    2016-01-01

    Purpose Argentina-Alzheimer’s Disease Neuroimaging Initiative (Arg-ADNI) is the first ADNI study to be performed in Latin America at a medical center with the appropriate infrastructure. Our objective was to describe baseline characteristics and to examine whether biomarkers related to Alzheimer’s disease (AD) physiopathology were associated with worse memory performance. Patients and methods Fifteen controls and 28 mild cognitive impairment and 13 AD dementia subjects were included. For Arg-ADNI, all biomarker parameters and neuropsychological tests of ADNI-II were adopted. Results of positron emission tomography (PET) with fluorodeoxyglucose and 11C-Pittsburgh compound-B (PIB-PET) were available from all participants. Cerebrospinal fluid biomarker results were available from 39 subjects. Results A total of 56 participants were included and underwent baseline evaluation. The three groups were similar with respect to years of education and sex, and they differed in age (F=5.10, P=0.01). Mean scores for the baseline measurements of the neuropsychological evaluation differed significantly among the three groups at P<0.001, showing a continuum in their neuropsychological performance. No significant correlations were found between the principal measures (long-delay recall, C-Pittsburgh compound-B scan, left hippocampal volume, and APOEε4) and either age, sex, or education (P>0.1). Baseline amyloid deposition and left hippocampal volume separated the three diagnostic groups and correlated with the memory performance (P<0.001). Conclusion Cross-sectional analysis of baseline data revealed links between cognition, structural changes, and biomarkers. Follow-up of a larger and more representative cohort, particularly analyzing cerebrospinal fluid and brain biomarkers, will allow better characterization of AD in our country. PMID:27695331

  12. Immunological memory to hyperphosphorylated tau in asymptomatic individuals.

    PubMed

    Pascual, Gabriel; Wadia, Jehangir S; Zhu, Xueyong; Keogh, Elissa; Kükrer, Başak; van Ameijde, Jeroen; Inganäs, Hanna; Siregar, Berdien; Perdok, Gerrard; Diefenbach, Otto; Nahar, Tariq; Sprengers, Imke; Koldijk, Martin H; der Linden, Els C Brinkman-van; Peferoen, Laura A; Zhang, Heng; Yu, Wenli; Li, Xinyi; Wagner, Michelle; Moreno, Veronica; Kim, Julie; Costa, Martha; West, Kiana; Fulton, Zara; Chammas, Lucy; Luckashenak, Nancy; Fletcher, Lauren; Holland, Trevin; Arnold, Carrie; Anthony Williamson, R; Hoozemans, Jeroen J; Apetri, Adrian; Bard, Frederique; Wilson, Ian A; Koudstaal, Wouter; Goudsmit, Jaap

    2017-05-01

    Several reports have described the presence of antibodies against Alzheimer's disease-associated hyperphosphorylated forms of tau in serum of healthy individuals. To characterize the specificities that can be found, we interrogated peripheral IgG(+) memory B cells from asymptomatic blood donors for reactivity to a panel of phosphorylated tau peptides using a single-cell screening assay. Antibody sequences were recovered, cloned, and expressed as full-length IgGs. In total, 52 somatically mutated tau-binding antibodies were identified, corresponding to 35 unique clonal families. Forty-one of these antibodies recognize epitopes in the proline-rich and C-terminal domains, and binding of 26 of these antibodies is strictly phosphorylation dependent. Thirteen antibodies showed inhibitory activity in a P301S lysate seeded in vitro tau aggregation assay. Two such antibodies, CBTAU-7.1 and CBTAU-22.1, which bind to the proline-rich and C-terminal regions of tau, respectively, were characterized in more detail. CBTAU-7.1 recognizes an epitope that is similar to that of murine anti-PHF antibody AT8, but has different phospho requirements. Both CBTAU-7.1 and CBTAU-22.1 detect pathological tau deposits in post-mortem brain tissue. CBTAU-7.1 reveals a similar IHC distribution pattern as AT8, immunostaining (pre)tangles, threads, and neuritic plaques. CBTAU-22.1 shows selective detection of neurofibrillary changes by IHC. Taken together, these results suggest the presence of an ongoing antigen-driven immune response against tau in healthy individuals. The wide range of specificities to tau suggests that the human immune repertoire may contain antibodies that can serve as biomarkers or be exploited for therapy.

  13. Investigating trajectories of social recovery in individuals with first-episode psychosis: a latent class growth analysis

    PubMed Central

    Hodgekins, Jo; Birchwood, Max; Christopher, Rose; Marshall, Max; Coker, Sian; Everard, Linda; Lester, Helen; Jones, Peter; Amos, Tim; Singh, Swaran; Sharma, Vimal; Freemantle, Nick; Fowler, David

    2015-01-01

    Background Social disability is a hallmark of severe mental illness yet individual differences and factors predicting outcome are largely unknown. Aim To explore trajectories and predictors of social recovery following a first episode of psychosis (FEP). Method A sample of 764 individuals with FEP were assessed on entry into early intervention in psychosis (EIP) services and followed up over 12 months. Social recovery profiles were examined using latent class growth analysis. Results Three types of social recovery profile were identified: Low Stable (66%), Moderate-Increasing (27%), and High-Decreasing (7%). Poor social recovery was predicted by male gender, ethnic minority status, younger age at onset of psychosis, increased negative symptoms, and poor premorbid adjustment. Conclusions Social disability is prevalent in FEP, although distinct recovery profiles are evident. Where social disability is present on entry into EIP services it can remain stable, highlighting a need for targeted intervention. PMID:26294371

  14. Working Memory Capacity and Categorization: Individual Differences and Modeling

    ERIC Educational Resources Information Center

    Lewandowsky, Stephan

    2011-01-01

    Working memory is crucial for many higher-level cognitive functions, ranging from mental arithmetic to reasoning and problem solving. Likewise, the ability to learn and categorize novel concepts forms an indispensable part of human cognition. However, very little is known about the relationship between working memory and categorization, and…

  15. Early Memories of Individuals on the Autism Spectrum Assessed Using Online Self-Reports

    PubMed Central

    Zamoscik, Vera; Mier, Daniela; Schmidt, Stephanie N. L.; Kirsch, Peter

    2016-01-01

    “When I was one and a half years old, I was on a ferry lying on red seats” – while several autobiographical accounts by people with autism reveal vivid memories of early childhood, the vast amount of experimental investigations found deficits in personal autobiographic memory in autism. To assess this contradiction empirically, we implemented an online questionnaire on early childhood events to compare people on the autism spectrum (AS) and non-autistic people with respect to their earliest autobiographical episodic memories and the earliest semantic know event as told by another person. Results indicate that people on the AS do not differ from non-autistic people in the age of their earliest know events but remember events from an earlier age in childhood and with more sensory details, contradicting the assumption of an overall deficit in personal episodic memory in autism. Furthermore, our results emphasize the supporting influence of language for memory formation and give evidence for an important role of sensory features in memories of people on the AS. PMID:27199786

  16. Individual Differences in Susceptibility to False Memory in the Deese-Roediger-McDermott Paradigm

    ERIC Educational Resources Information Center

    Watson, Jason M.; Bunting, Michael F.; Poole, Bradley J.; Conway, Andrew R. A.

    2005-01-01

    The authors addressed whether individual differences in the working memory capacity (WMC) of young adults influence susceptibility to false memories for nonpresented critical words in the Deese-Roediger-McDermott associative list paradigm. The results of 2 experiments indicated that individuals with greater WMC recalled fewer critical words than…

  17. Longitudinal changes in prospective memory and their clinical correlates at 1-year follow-up in first-episode schizophrenia

    PubMed Central

    Ungvari, Gabor S.; Ng, Chee H.; Zhou, Yan; Zhang, Liang; Zhou, Jingjing; Shum, David H. K.; Man, David; Liu, Deng-Tang; Li, Jun; Xiang, Yu-Tao

    2017-01-01

    This study aimed to investigate prospective memory (PM) and the association with clinical factors at 1-year follow-up in first-episode schizophrenia (FES). Thirty-two FES patients recruited from a university-affiliated psychiatric hospital in Beijing and 17 healthy community controls (HCs) were included. Time- and event-based PM (TBPM and EBPM) performances were measured with the Chinese version of the Cambridge Prospective Memory Test (C-CAMPROMPT) at baseline and at one-year follow-up. A number of other neurocognitive tests were also administered. Remission was determined at the endpoint according to the PANSS score ≤ 3 for selected items. Repeated measures analysis of variance revealed a significant interaction between time (baseline vs. endpoint) and group (FES vs. HCs) for EBPM (F(1, 44) = 8.8, p = 0.005) and for all neurocognitive components. Paired samples t-tests showed significant improvement in EBPM in FES (13.1±3.7 vs. 10.3±4.8; t = 3.065, p = 0.004), compared to HCs (15.7±3.6 vs. 16.5±2.3; t = -1.248, p = 0.230). A remission rate of 59.4% was found in the FES group. Analysis of covariance revealed that remitters performed significantly better on EBPM (14.9±2.6 vs. 10.4±3.6; F(1, 25) = 12.2, p = 0.002) than non-remitters at study endpoint. The association between EBPM and 12-month clinical improvement in FES suggests that EBPM may be a potential neurocognitive marker for the effectiveness of standard pharmacotherapy. Furthermore, the findings also imply that PM may not be strictly a trait-related endophenotype as indicated in previous studies. PMID:28245266

  18. Developmental changes in the engagement of episodic retrieval processes and their relationship with working memory during the period of middle childhood.

    PubMed

    Rhodes, Sinéad M; Murphy, Derek; Hancock, Peter J B

    2011-11-01

    We examined the development of children's engagement of the episodic retrieval processes of recollection and familiarity and their relationship with working memory (WM). Ninety-six children (24 in four groups aged 8, 9, 10, and 11 years) and 24 adults performed an episodic memory (EM) task involving old/new, remember/know (R/K), and source memory judgements and numerous WM tasks that assessed verbal and spatial components of WM and delayed short-term memory (STM). Developmental changes were observed in EM with younger children (8-, 9-, 10-year-olds) making fewer remember responses than 11-year-olds and adults while 11-year-olds did not differ from adults. Only children aged 10 years plus showed a relationship between EM and WM. EM was related to verbal executive WM in 10- and 11-year-old children suggesting that children at this stage use verbal strategies to aid EM. In contrast, EM was related to spatial executive WM in adults. The engagement of episodic retrieval processes appears to be selectively related to executive components of verbal and spatial WM, the pattern of which differs in children and adults.

  19. Subtle hippocampal deformities in breast cancer survivors with reduced episodic memory and self-reported cognitive concerns.

    PubMed

    Apple, Alexandra C; Ryals, Anthony J; Alpert, Kathryn I; Wagner, Lynne I; Shih, Pei-An; Dokucu, Mehmet; Cella, David; Penedo, Frank J; Voss, Joel L; Wang, Lei

    2017-01-01

    Cancer survivors have lingering cognitive problems, however the anatomical basis for these problems has yet to be fully elucidated. Clinical studies as well as animal models of chemotherapy have pinpointed cell and volume loss to the hippocampus, however, few studies have performed shape analysis of the hippocampus on cancer survivors. This study used high-dimensional deformation mapping analysis to test whether localized hippocampal deformation differs in breast cancer survivors who received adjuvant chemotherapy coupled with hormone blockade therapy, and if deformation was related to subjective self-reported concerns and cognitive performance. 3 T MRI images were acquired from 16 pre-menopausal breast cancer survivors and 18 healthy controls without a history of cancer. Breast cancer survivors had undergone chemotherapy within the eighteen months prior to the study, and were receiving estrogen-blockade therapy at the time of the study. Automated high-dimensional deformation mapping was used to compare localized hippocampal deformation differences between groups. Self-reported subjective concerns were assessed using Neuro-QOL Cognitive Function assessment, whereas cognitive performance was evaluated using the NIH Toolbox Cognition Battery. Relative to healthy controls, cancer survivors showed significantly more inward hippocampal deformation, worse self-reported cognitive functioning, and inferior episodic memory test score. This study is the first of its kind to examine the relationship between hippocampal deformity and cognitive impairment in cancer survivors.

  20. Daily Carnosine and Anserine Supplementation Alters Verbal Episodic Memory and Resting State Network Connectivity in Healthy Elderly Adults

    PubMed Central

    Rokicki, Jaroslav; Li, Lucia; Imabayashi, Etsuko; Kaneko, Jun; Hisatsune, Tatsuhiro; Matsuda, Hiroshi

    2015-01-01

    Carnosine and anserine are strong antioxidants, previously demonstrated to reduce cognitive decline in animal studies. We aimed to investigate their cognitive and neurophysiological effects, using functional MRI, on humans. Thirty-one healthy participants (age 40–78, 10 male/21 female) were recruited to a double-blind placebo-controlled study. Participants were assigned to twice-daily doses of imidazole dipeptide formula (n = 14), containing 500 mg (carnosine/anserine, ratio 1/3) or an identical placebo (n = 17). Functional MRI and neuropsychological assessments were carried out at baseline and after 3 months of supplementation. We analyzed resting state functional connectivity with the FSL fMRI analysis package. There were no differences in neuropsychological scores between the groups at baseline. After 3 months of supplementation, the carnosine/anserine group had better verbal episodic memory performance and decreased connectivity in the default mode network, the posterior cingulate cortex and the right fronto parietal network, as compared with the placebo group. Furthermore, there was a correlation between the extents of cognitive and neuroimaging changes. These results suggest that daily carnosine/anserine supplementation can impact cognitive function and that network connectivity changes are associated with its effects. PMID:26640437

  1. Individual Differences in Learning Talker Categories: The Role of Working Memory

    PubMed Central

    Levi, Susannah V.

    2016-01-01

    The current study explores the question of how an auditory category is learned by having school-age listeners learn to categorize speech not in terms of linguistic categories, but instead in terms of talker categories (i.e., who is talking). Findings from visual-category learning indicate that working memory skills affect learning, but the literature is equivocal: sometimes better working memory is advantageous, and sometimes not. The current study examined the role of different components of working memory to test which component skills benefit, and which hinder, learning talker categories. Results revealed that the short-term storage component positively predicted learning, but that the Central Executive and Episodic Buffer negatively predicted learning. As with visual categories, better working memory is not always an advantage. PMID:25721393

  2. Strategy difficulty effects in young and older adults' episodic memory are modulated by inter-stimulus intervals and executive control processes.

    PubMed

    Burger, Lucile; Uittenhove, Kim; Lemaire, Patrick; Taconnat, Laurence

    2017-04-01

    Efficient execution of strategies is crucial to memory performance and to age-related differences in this performance. Relative strategy complexity influences memory performance and aging effects on memory. Here, we aimed to further our understanding of the effects of relative strategy complexity by looking at the role of cognitive control functions and the time-course of the effects of relative strategy complexity. Thus, we manipulated inter-stimulus intervals (ISI) and assessed executive functions. Results showed that (a) performance as a function of the relative strategy difficulty of the current and previous trial was modulated by ISI, (b) these effects were modulated by inhibition capacities, and (c) significant age differences were found in the way ISI modulates relative strategy difficulty. These findings have important implications for understanding the relationships between aging, executive control, and strategy execution in episodic memory.

  3. Temporal Context Memory in High-Functioning Autism

    ERIC Educational Resources Information Center

    Gras-Vincendon, Agnes; Mottron, Laurent; Salame, Pierre; Bursztejn, Claude; Danion, Jean-Marie

    2007-01-01

    Episodic memory, i.e. memory for specific episodes situated in space and time, seems impaired in individuals with autism. According to weak central coherence theory, individuals with autism have general difficulty connecting contextual and item information which then impairs their capacity to memorize information in context. This study…

  4. Main effects and interactions of cerebral hemispheres, gender, and age in the calculation of volumes and asymmetries of selected structures of episodic memory

    PubMed Central

    Ramirez-Carmona, Rocio; Garcia-Lazaro, Haydee Guadalupe; Dominguez-Corrales, Brenda; Aguilar-Castañeda, Erika; Roldan-Valadez, Ernesto

    2016-01-01

    Summary The aim of this study was to clarify the influence of anatomical (cerebral hemisphere) and demographic (age and gender) variables on the gray matter (GM) volumes and volumetric asymmetry indices (VAIs) of selected structures involved in episodic memory. A cross-sectional study was performed in 47 healthy volunteers. Neuropsychological evaluation revealed similar IQs across the sample. Using SPM-based software, brain segmentation, labeling and volume measurements of the hippocampus, amygdala, middle temporal gyrus and parahippocampal gyrus were performed in each cerebral hemisphere. A two-way between-groups multivariate analysis of covariance (MANCOVA) was applied to GM volumes and VAIs. The main effects of gender and cerebral hemisphere on GM volumes were significant (p < .001), while there was no significant interaction effect between gender and cerebral hemisphere. VAI measurements showed a non-significant effect of gender, but a significant influence of age (p = .015). The linear model of interactions and main effects explained 33% of the variance influencing the GM volume quantification. While cerebral hemisphere and gender were found to affect the volumes of brain structures involved in episodic memory, the calculation of VAIs was affected only by age. A comprehensive understanding of the main effects and interaction effects of cerebral hemisphere, gender and age on the volumes and asymmetries of structures related to episodic memory might help neurologists, psychiatrists, geriatricians and other neuroscientists in the study of degenerative brain diseases. PMID:28072386

  5. Main effects and interactions of cerebral hemispheres, gender, and age in the calculation of volumes and asymmetries of selected structures of episodic memory.

    PubMed

    Ramirez-Carmona, Rocio; Garcia-Lazaro, Haydee Guadalupe; Dominguez-Corrales, Brenda; Aguilar-Castañeda, Erika; Roldan-Valadez, Ernesto

    The aim of this study was to clarify the influence of anatomical (cerebral hemisphere) and demographic (age and gender) variables on the gray matter (GM) volumes and volumetric asymmetry indices (VAIs) of selected structures involved in episodic memory. A cross-sectional study was performed in 47 healthy volunteers. Neuropsychological evaluation revealed similar IQs across the sample. Using SPM-based software, brain segmentation, labeling and volume measurements of the hippocampus, amygdala, middle temporal gyrus and parahippocampal gyrus were performed in each cerebral hemisphere. A two-way between-groups multivariate analysis of covariance (MANCOVA) was applied to GM volumes and VAIs. The main effects of gender and cerebral hemisphere on GM volumes were significant (p < .001), while there was no significant interaction effect between gender and cerebral hemisphere. VAI measurements showed a nonsignificant effect of gender, but a significant influence of age (p = .015). The linear model of interactions and main effects explained 33% of the variance influencing the GM volume quantification. While cerebral hemisphere and gender were found to affect the volumes of brain structures involved in episodic memory, the calculation of VAIs was affected only by age. A comprehensive understanding of the main effects and interaction effects of cerebral hemisphere, gender and age on the volumes and asymmetries of structures related to episodic memory might help neurologists, psychiatrists, geriatricians and other neuroscientists in the study of degenerative brain diseases.

  6. Individual Differences in Learning and Memory. Final Report.

    ERIC Educational Resources Information Center

    Wimer, Richard E.

    A battery of behavioral tests yielding 79 measures, many of which were presumably related to learning and memory, was administered to house mice of seven inbred strains. An analysis of the factorial structure indicated that the two principal and most pervasive factors underlying performance on the battery involved the initiation and maintenance of…

  7. Individual Differences in the Effects of Retrieval from Long-Term Memory

    ERIC Educational Resources Information Center

    Brewer, Gene A.; Unsworth, Nash

    2012-01-01

    The current study examined individual differences in the effects of retrieval from long-term memory (i.e., the testing effect). The effects of retrieving from memory make tested information more accessible for future retrieval attempts. Despite the broad applied ramifications of such a potent memorization technique there is a paucity of research…

  8. Variation in Cognitive Failures: An Individual Differences Investigation of Everyday Attention and Memory Failures

    ERIC Educational Resources Information Center

    Unsworth, Nash; Brewer, Gene A.; Spillers, Gregory J.

    2012-01-01

    The present study examined individual differences in everyday cognitive failures assessed by diaries. A large sample of participants completed various cognitive ability measures in the laboratory. Furthermore, a subset of these participants also recorded everyday cognitive failures (attention, retrospective memory, and prospective memory failures)…

  9. Multimedia Learning and Individual Differences: Mediating the Effects of Working Memory Capacity with Segmentation

    ERIC Educational Resources Information Center

    Lusk, Danielle L.; Evans, Amber D.; Jeffrey, Thomas R.; Palmer, Keith R.; Wikstrom, Chris S.; Doolittle, Peter E.

    2009-01-01

    Research in multimedia learning lacks an emphasis on individual difference variables, such as working memory capacity (WMC). The effects of WMC and the segmentation of multimedia instruction were examined by assessing the recall and application of low (n = 66) and high (n = 67) working memory capacity students randomly assigned to either a…

  10. The Relation between Navigation Strategy and Associative Memory: An Individual Differences Approach

    ERIC Educational Resources Information Center

    Ngo, Chi T.; Weisberg, Steven M.; Newcombe, Nora S.; Olson, Ingrid R.

    2016-01-01

    Although the hippocampus is implicated in both spatial navigation and associative memory, very little is known about whether individual differences in the 2 domains covary. People who prefer to navigate using a hippocampal-dependent place strategy may show better performance on associative memory tasks than those who prefer a caudate-dependent…

  11. Working Memory Capacity and Mobile Multimedia Learning Environments: Individual Differences in Learning While Mobile

    ERIC Educational Resources Information Center

    Doolittle, Peter E.; Mariano, Gina J.

    2008-01-01

    The present study examined the effects of individual differences in working memory capacity (WMC) on learning from an historical inquiry multimedia tutorial in stationary versus mobile learning environments using a portable digital media player (i.e., iPod). Students with low (n = 44) and high (n = 40) working memory capacity, as measured by the…

  12. Working Memory and Mathematics: A Review of Developmental, Individual Difference, and Cognitive Approaches

    ERIC Educational Resources Information Center

    Raghubar, Kimberly P.; Barnes, Marcia A.; Hecht, Steven A.

    2010-01-01

    Working memory refers to a mental workspace, involved in controlling, regulating, and actively maintaining relevant information to accomplish complex cognitive tasks (e.g. mathematical processing). Despite the potential relevance of a relation between working memory and math for understanding developmental and individual differences in…

  13. Collective memory: collaborative and individual processes in remembering.

    PubMed

    Weldon, M S; Bellinger, K D

    1997-09-01

    Two experiments compared collaborative and individual recall. In Experiment 1, participants encoded pictures and words with a deep or shallow processing task, then recalled them twice either individually or collaboratively. Collaborative groups recalled more than individuals, but less than nominal groups (pooled individuals), thus exhibiting collaborative inhibition. However, group recall appeared to be more stable over time than individual recall. Groups and individuals both showed a picture-superiority effect, a level-of-processing effect, and hypermnesia. In Experiment 2, participants recalled the story "War of the Ghosts" (from F. C. Bartlett, 1932), and again collaborative groups recalled more than individuals, but less than nominal groups. Both the individual and collaborative recalls were highly organized. There was evidence that the collaborative groups tended to rely on the best individual to a greater extent in story than in list recall. Possible social and cognitive mechanisms are considered.

  14. The potent M1 receptor allosteric agonist GSK1034702 improves episodic memory in humans in the nicotine abstinence model of cognitive dysfunction.

    PubMed

    Nathan, Pradeep J; Watson, Jeannette; Lund, Jesper; Davies, Ceri H; Peters, Gary; Dodds, Chris M; Swirski, Bridget; Lawrence, Philip; Bentley, Graham D; O'Neill, Barry V; Robertson, Jon; Watson, Stephen; Jones, Gareth A; Maruff, Paul; Croft, Rodney J; Laruelle, Marc; Bullmore, Edward T

    2013-05-01

    Episodic memory deficits are a core feature of neurodegenerative disorders. Muscarinic M(1) receptors play a critical role in modulating learning and memory and are highly expressed in the hippocampus. We examined the effect of GSK1034702, a potent M(1) receptor allosteric agonist, on cognitive function, and in particular episodic memory, in healthy smokers using the nicotine abstinence model of cognitive dysfunction. The study utilized a randomized, double-blind, placebo-controlled, cross-over design in which 20 male nicotine abstained smokers were tested following single doses of placebo, 4 and 8 mg GSK1034702. Compared to the baseline (nicotine on-state), nicotine abstinence showed statistical significance in reducing immediate (p=0.019) and delayed (p=0.02) recall. GSK1034702 (8 mg) significantly attenuated (i.e. improved) immediate recall (p=0.014) but not delayed recall. None of the other cognitive domains was modulated by either nicotine abstinence or GSK1034702. These findings suggest that stimulating M(1) receptor mediated neurotransmission in humans with GSK1034702 improves memory encoding potentially by modulating hippocampal function. Hence, selective M(1) receptor allosteric agonists may have therapeutic benefits in disorders of impaired learning including Alzheimer's disease.

  15. The formation of novel social category conjunctions in working memory: A possible role for the episodic buffer?

    PubMed

    Hutter, Russell R C; Allen, Richard J; Wood, Chantelle

    2016-01-01

    Recent research (e.g., Hutter, Crisp, Humphreys, Waters, & Moffit; Siebler) has confirmed that combining novel social categories involves two stages (e.g., Hampton; Hastie, Schroeder, & Weber). Furthermore, it is also evident that following stage 1 (constituent additivity), the second stage in these models involves cognitively effortful complex reasoning. However, while current theory and research has addressed how category conjunctions are initially represented to some degree, it is not clear precisely where we first combine or bind existing social constituent categories. For example, how and where do we compose and temporarily store a coherent representation of an individual who shares membership of "female" and "blacksmith" categories? In this article, we consider how the revised multi-component model of working memory (Baddeley) can assist in resolving the representational limitations in the extant two-stage theoretical models. This is a new approach to understanding how novel conjunctions form new bound "composite" representations.

  16. Hue-specific colour memory impairment in an individual with intact colour perception and colour naming.

    PubMed

    Jakobson, L S; Pearson, P M; Robertson, B

    2008-01-15

    Cases of hue-selective dyschomatopsias, together with the results of recent optical imaging studies [Xiao, Y., Casti, A. R. R., Xiao, J., & Kaplan, E. (2006). A spatially organized representation of colour in macaque primary visual cortex. Perception, 35, ECVP Abstract Supplement; Xiao, Y., Wang, Y., & Felleman, D. J. (2003). A spatially organized representation of colour in macaque cortical area V2. Nature, 421, 535-539], have provided support for the idea that different colours are processed in spatially distinct regions of extrastriate cortex. In the present report, we provide evidence suggesting that a similar, but distinct, map may exist for representations of colour in memory. This evidence comes from observations of a young woman (QP) who demonstrates an isolated deficit in colour memory secondary to a concussive episode. Despite having normal colour perception and colour naming skills, and above-average memory skills in other domains, QP's ability to recall visually encoded colour information over short retention intervals is dramatically impaired. Her long-term memory for colour and her colour imagery skills are also abnormal. Surprisingly, however, these impairments are not seen with all hues; specifically, her ability to remember or imagine blue shades is spared. This interesting case contributes to the literature suggesting that colour perception, naming, and memory can be clinically dissociated, and provides insights into the organization of colour information in memory.

  17. The development of strategy use in elementary school children: working memory and individual differences.

    PubMed

    Imbo, Ineke; Vandierendonck, André

    2007-04-01

    The current study tested the development of working memory involvement in children's arithmetic strategy selection and strategy efficiency. To this end, an experiment in which the dual-task method and the choice/no-choice method were combined was administered to 10- to 12-year-olds. Working memory was needed in retrieval, transformation, and counting strategies, but the ratio between available working memory resources and arithmetic task demands changed across development. More frequent retrieval use, more efficient memory retrieval, and more efficient counting processes reduced the working memory requirements. Strategy efficiency and strategy selection were also modified by individual differences such as processing speed, arithmetic skill, gender, and math anxiety. Short-term memory capacity, in contrast, was not related to children's strategy selection or strategy efficiency.

  18. Picturing neuroscience research through a human rights lens: imaging first-episode schizophrenic treatment-naive individuals.

    PubMed

    Eijkholt, Marleen; Anderson, James A; Illes, Judy

    2012-01-01

    In this paper we examine imaging research involving first-episode schizophrenic treatment-naive individuals (FESTNIs) through a legal human rights lens; in particular, the lens of the Additional Protocol to the Convention on Human Rights and Biomedicine Concerning Biomedical Research. We identify a number of ethical and legal hot spots highlighted by the Protocol, and offer a series of recommendations designed to ensure the human rights compatibility of this research. Subsequently, we argue that the lack of reporting on design elements related to ethical concerns frustrates commitments at the heart of the human rights approach, namely, transparency and openness to international scrutiny. To redress this problem, we introduce two norms for the first time: ethical transparency, and ethical reproducibility. When concluding, we offer a set of reporting guidelines designed to operationalize these norms in the context of imaging research involving FESTNIs. Though we will not make this case here, we believe that parallel reporting guidelines should be incorporated into other areas of research involving human subjects.

  19. Memory specificity and mindfulness jointly moderate the effect of reflective pondering on depressive symptoms in individuals with a history of recurrent depression.

    PubMed

    Brennan, Kate; Barnhofer, Thorsten; Crane, Catherine; Duggan, Danielle; Williams, J Mark G

    2015-05-01

    In previously depressed individuals, reflective thinking may easily get derailed and lead to detrimental effects. This study investigated the conditions in which such thinking is, or is not, adaptive. Levels of mindfulness and autobiographical memory specificity were assessed as potential moderators of the relationship between reflective thinking and depressive symptoms. Two hundred seventy-four individuals with a history of three or more previous episodes of depression completed self-report measures of depressive symptoms, rumination-including subscales for reflection and brooding-and mindfulness, as well as an autobiographical memory task to assess memory specificity. In those low in both mindfulness and memory specificity, higher levels of reflection were related to more depressive symptoms, whereas in all other groups higher levels of reflection were related to fewer depressive symptoms. The results demonstrate that the relation between reflective pondering and depressive symptoms varies depending on individual state or trait factors. In previously depressed individuals, the cognitive problem-solving aspect of reflection may be easily hampered when tendencies toward unspecific processing are increased, and awareness of mental processes such as self-judgment and reactivity is decreased.

  20. COGNITION-EMOTION INTERACTIONS ARE MODULATED BY WORKING MEMORY CAPACITY IN INDIVIDUALS WITH SCHIZOPHRENIA

    PubMed Central

    Strauss, Gregory P.; Lee, Bern G.; Waltz, James A.; Robinson, Benjamin M.; Brown, Jaime K.; Gold, James M.

    2012-01-01

    Prior research provides evidence for aberrant cognition-emotion interactions in schizophrenia. In the current study, we aimed to extend these findings by administering the “distractor devaluation” task to 40 individuals with schizophrenia and 32 demographically matched healthy controls. The task consisted of a simple visual search task for neutral faces, followed by an evaluative response made for one of the search items (or a novel item) to determine whether prior attentional selection results in a devaluation of a previously unattended stimulus. We also manipulated working memory demands by preceding the search array with a memory array that required subjects to hold 0, 1, or 2 items in working memory while performing the search array and devaluation task, to determine whether the normative process by which attentional states influence evaluative response is limited by working memory capacity. Results indicated that individuals with schizophrenia demonstrated the typical distractor devaluation effect at working memory load 0, suggesting intact evaluative response. However, the devaluation effect was absent at working memory loads of 1 and 2, suggesting that normal evaluative responses can be abolished in people with schizophrenia when working memory capacity is exceeded. Thus, findings provide further evidence for normal evaluative response in schizophrenia, but clarify that these normal experiences may not hold when working memory demands are too high. PMID:22968207

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

    PubMed

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

    2017-05-01

    Cannabinoid-mediated memory impairment is a concern in cannabinoid-based therapies. Caffeine exacerbates cannabinoid CB1 receptor (CB1R)-induced memory deficits through an adenosine A1 receptor-mediated mechanism. We now evaluated how chronic or acute blockade of adenosine A2A receptors (A2ARs) affects long-term episodic memory deficits induced by a single injection of a selective CB1R agonist. Long-term episodic memory was assessed by the novel object recognition (NOR) test. Mice received an intraperitoneal (i.p.) injection of the CB1/CB2 receptor agonist WIN 55,212-2 (1 mg/kg) immediately after the NOR training, being tested for novelty recognition 24 h later. Anxiety levels were assessed by the Elevated Plus Maze test, immediately after the NOR. Mice were also tested for exploratory behaviour at the Open Field. For chronic A2AR blockade, KW-6002 (istradefylline) (3 mg/kg/day) was administered orally for 30 days; acute blockade of A2ARs was assessed by i.p. injection of SCH 58261 (1 mg/kg) administered either together with WIN 55,212-2 or only 30 min before the NOR test phase. The involvement of CB1Rs was assessed by using the CB1R antagonist, AM251 (3 mg/kg, i.p.). WIN 55,212-2 caused a disruption in NOR, an action absent in mice also receiving AM251, KW-6002 or SCH 58261 during the encoding/consolidation phase; SCH 58251 was ineffective if present during retrieval only. No effects were detected in the Elevated Plus maze or Open Field Test. The finding that CB1R-mediated memory disruption is prevented by antagonism of adenosine A2ARs, highlights a possibility to prevent cognitive side effects when therapeutic application of CB1R drugs is desired.

  2. Caudate nucleus-dependent response strategies in a virtual navigation task are associated with lower basal cortisol and impaired episodic memory.

    PubMed

    Bohbot, Véronique D; Gupta, Melini; Banner, Harrison; Dahmani, Louisa

    2011-09-01

    The present research examined the relationship between endogenous glucocorticoids, navigational strategies in a virtual navigation task, and performance on standard neuropsychological assessments of memory. Healthy young adult participants (N=66, mean age: 21.7) were tested on the 4 on 8 virtual maze (4/8 VM) and standard neuropsychological tests such as the Rey-Osterrieth Complex Figure (RO) and the Rey Auditory Verbal Learning Task (RAVLT), which measure episodic memory. The 4/8 VM differentiates between navigational strategies, where participants either use a hippocampal-dependent spatial strategy by building relationships between landmarks, or a caudate nucleus-dependent stimulus-response strategy by automatizing a pattern of open and closed arms to learn the location of objects within the maze. Degree of stress was assessed by administering the Perceived Stress Scale (PSS) questionnaire. Cortisol samples were taken on two consecutive days upon waking, 30 min after waking, at 11 am, 4 pm, and 9 pm. There was a significant difference in basal levels of cortisol between spatial and response learners. Interestingly, response learners had significantly lower cortisol levels throughout the day. The two groups did not differ in terms of perceived stress as measured with the PSS questionnaire. Moreover, there was no significant correlation between PSS scores and salivary cortisol levels, indicating that the higher cortisol levels in the spatial group were not associated with greater perceived stress. In addition, participants who spontaneously used a spatial strategy performed significantly better on the RAVLT and RO. These data indicate that the cortisol levels in the spatial group may be optimal in terms of episodic memory performance whereas the cortisol levels in the response group may be associated with poorer memory. These results are suggestive of an inverted U-shaped curve describing the effects of basal levels of circulating cortisol on memory in young adults.

  3. Learning and memory in individuals with agenesis of the corpus callosum.

    PubMed

    Paul, Lynn K; Erickson, Roger L; Hartman, Jo Ann; Brown, Warren S

    2016-06-01

    Damage to long white matter pathways in the cerebral cortex is known to affect memory capacity. However, the specific contribution of interhemispheric connectivity in memory functioning is only beginning to become understood. The present study examined verbal and visual memory processing in individuals with agenesis of the corpus callosum (AgCC) using the Wechsler Memory Scale-Third Edition (WMS-III; Wechsler, 1997b). Thirty participants with AgCC (FSIQ >78) were compared against 30 healthy age and IQ matched controls on auditory/verbal (Logical Memory, Verbal Paired Associates) and visual (Visual Reproduction, Faces) memory subtests. Performance was worse in AgCC than controls on immediate and delayed verbal recall for rote word pairs and on delayed recall of faces, as well as on percent recall for these tasks. Immediate recall for thematic information from stories was also worse in AgCC, but groups did not differ on memory for details from narratives or on recall for thematic information following a time delay. Groups also did not differ on memory for abstract figures or immediate recall of faces. On all subtests, individuals with AgCC had greater frequency of clinically significant impairments than predicted by the normal distribution. Results suggest less efficient overall verbal and visual learning and memory with relative weaknesses processing verbal pairs and delayed recall for faces. These findings suggest that the corpus callosum facilitates more efficient learning and recall for both verbal and visual information, that individuals with AgCC may benefit from receiving verbal information within semantic context, and that known deficits in facial processing in individuals with AgCC may contribute to their impairments in recall for faces.

  4. Veridical and False Pictorial Memory in Individuals with and without Mental Retardation

    ERIC Educational Resources Information Center

    Carlin, Michael T.; Toglia, Michael P.; Wakeford, Yvonne; Jakway, Allison; Sullivan, Kate; Hasel, Lisa

    2008-01-01

    Veridical and false pictorial recognition were assessed in individuals with mental retardation; groups were matched for MA and CA. Pictures were viewed in either a generative or static format at acquisition. The individuals with mental retardation and those in the MA-matched group had higher rates of false memories for critical items and lower hit…

  5. Visuospatial Support for Verbal Short-Term Memory in Individuals with Down Syndrome

    ERIC Educational Resources Information Center

    Duarte, Cintia Perez; Covre, Priscila; Braga, Ana Claudia; de Macedo, Elizeu Coutinho

    2011-01-01

    Individuals with Down syndrome (DS) tend to have impaired verbal short-term memory (STM), which persists even when visual support is provided for carrying out verbal tasks. Objective: The current study aims to investigate whether visuospatial support, rather than just visual, can compensate for verbal STM deficits in these individuals. The…

  6. Individual differences in memory and executive function abilities during normal aging.

    PubMed

    Mejia, S; Pineda, D; Alvarez, L M; Ardila, A

    1998-09-01

    The purpose of this study was to analyze the effects of some individual variables on memory and executive function test performance in normal aging individuals. Sixty subjects (21 males and 39 females), with a mean age of 69.66 (SD = 7.09) were selected. The following neuropsychological tests were selected. The following neuropsychological tests were administered: Associative Learning and Logical Memory from the Wechsler Memory Scale (WMS) (Wechsler, 1945), Associative Memory with Semantic Enhancement Test (AMSET) (Pineda, Galeano and Giraldo, 1991), Wisconsin Card Sorting Test (WSCT) (Heaton, 1981), and Verbal Fluency (phonologic and semantic). The effects of demographic (age, education, and sex) and some individual variables (academic history, working history, physical activity, and leisure activities) were measured. Age and education effects on test scores were observed, but no sex effect was found. Working history and leisure activities established significant differences in some test scores. A multiple regression analysis was performed. Not only demographic variables, but also individual variables were associated with memory, and albeit at a lesser extend, with executive function test scores. It was emphasized that not only demographic factors, but also individual variables have a significant effect on cognitive changes observed during normal aging.

  7. Working memory training improves emotional states of healthy individuals

    PubMed Central

    Takeuchi, Hikaru; Taki, Yasuyuki; Nouchi, Rui; Hashizume, Hiroshi; Sekiguchi, Atsushi; Kotozaki, Yuka; Nakagawa, Seishu; Miyauchi, Carlos Makoto; Sassa, Yuko; Kawashima, Ryuta

    2014-01-01

    Working memory (WM) capacity is associated with various emotional aspects, including states of depression and stress, reactions to emotional stimuli, and regulatory behaviors. We have previously investigated the effects of WM training (WMT) on cognitive functions and brain structures. However, the effects of WMT on emotional states and related neural mechanisms among healthy young adults remain unknown. In the present study, we investigated these effects in young adults who underwent WMT or received no intervention for 4 weeks. Before and after the intervention, subjects completed self-report questionnaires related to their emotional states and underwent scanning sessions in which brain activities related to negative emotions were measured. Compared with controls, subjects who underwent WMT showed reduced anger, fatigue, and depression. Furthermore, WMT reduced activity in the left posterior insula during tasks evoking negative emotion, which was related to anger. It also reduced activity in the left frontoparietal area. These findings show that WMT can reduce negative mood and provide new insight into the clinical applications of WMT, at least among subjects with preclinical-level conditions. PMID:25360090

  8. Differential conditioning and long-term olfactory memory in individual Camponotus fellah ants.

    PubMed

    Josens, Roxana; Eschbach, Claire; Giurfa, Martin

    2009-06-01

    Individual Camponotus fellah ants perceive and learn odours in a Y-maze in which one odour is paired with sugar (CS+) while a different odour (CS-) is paired with quinine (differential conditioning). We studied olfactory retention in C. fellah to determine whether olfactory learning leads to long-term memory retrievable 24 h and 72 h after training. One and 3 days after training, ants exhibited robust olfactory memory through a series of five successive retention tests in which they preferred the CS+ and stayed longer in the arm presenting it. In order to determine the nature of the associations memorized, we asked whether choices within the Y-maze were driven by excitatory memory based on choosing the CS+ and/or inhibitory memory based on avoiding the CS-. By confronting ants with a novel odour vs either the CS+ or the CS- we found that learning led to the formation of excitatory memory driving the choice of the CS+ but no inhibitory memory based on the CS- was apparent. Ants even preferred the CS- to the novel odour, thus suggesting that they used the CS- as a contextual cue in which the CS+ was embedded, or as a second-order cue predicting the CS+ and thus the sugar reward. Our results constitute the first controlled account of olfactory long-term memory in individual ants for which the nature of associations could be precisely characterized.

  9. Autobiographical Memory, Autonoetic Consciousness, and Identity in Asperger Syndrome

    ERIC Educational Resources Information Center

    Tanweer, Tilait; Rathbone, Clare J.; Souchay, Celine

    2010-01-01

    Previous results from research on individuals with Asperger syndrome (AS) suggest a diminished ability for recalling episodic autobiographical memory (AM). The primary aim of this study was to explore autobiographical memory in individuals with Asperger syndrome and specifically to investigate whether memories in those with AS are characterized by…

  10. The effect of individual differences in working memory capacity on sentence comprehension: an FMRI study.

    PubMed

    Newman, Sharlene D; Malaia, Evie; Seo, Roy; Cheng, Hu

    2013-07-01

    This study explores the interaction between working memory systems and language processing by examining how differences in working memory capacity (WMC) modulates neural activation levels and functional connectivity during sentence comprehension. The results indicate that two working memory systems may be involved in sentence comprehension, the verbal working memory system and the episodic buffer, but during different phases of the task. A sub-region of the left inferior frontal gyrus (BA 45) was correlated with WMC during the probe and not during sentence reading while the only region to reveal a correlation with WMC during sentence reading was the posterior cingulate/precuneus area, a region linked to event representation. In addition, functional connectivity analysis suggests that there were two distinct networks affected by WMC. The first was a semantic network that included the middle temporal cortex, an anterior region of the inferior frontal gyrus and the inferior parietal region. The second included the posterior cingulate and BA 45 of the inferior frontal gyrus. We propose here that high capacity readers may generate an event representation of the sentence during reading that aids in comprehension and that this event representation involves the processing of the posterior cingulate cortex.

  11. Influence of electroencephalography neurofeedback training on episodic memory: a randomized, sham-controlled, double-blind study.

    PubMed

    Guez, Jonathan; Rogel, Ainat; Getter, Nir; Keha, Eldad; Cohen, Tzlil; Amor, Tali; Gordon, Shirley; Meiran, Nachshon; Todder, Doron

    2015-01-01

    The relationships between memory processes and oscillatory electroencephalography (EEG) are well established. Neurofeedback training (NFT) may cause participants to better regulate their brain EEG oscillations. The present study is a double-blind sham-controlled design investigating the effect of NFT on memory. NFT included up-training upper alpha (UA) band, up-training sensory-motor rhythm (SMR) band and sham protocol. Thirty healthy adult volunteers were randomly divided into three treatment groups. NFT sessions (30 min each) took place twice weekly for a total of 10 sessions while memory testing took place pre- and post-training. The results indicate dissociation between SMR and UA NFT and different memory processes. While the SMR protocol resulted in improving automatic, item-specific and familiarity-based processes in memory, the UA protocol resulted in improved strategic and controlled recollection. The implications of the results are discussed.

  12. Episodic memory in former professional football players with a history of concussion: an event-related functional neuroimaging study.

    PubMed

    Ford, Jaclyn H; Giovanello, Kelly S; Guskiewicz, Kevin M

    2013-10-15

    Previous research has demonstrated that sport-related concussions can have short-term effects on cognitive processes, but the long-term consequences are less understood and warrant more research. This study was the first to use event-related functional magnetic resonance imaging (fMRI) to examine long-term differences in neural activity during memory tasks in former athletes who have sustained multiple sport-related concussions. In an event-related fMRI study, former football players reporting multiple sport-related concussions (i.e., three or more) were compared with players who reported fewer than three concussions during a memory paradigm examining item memory (i.e., memory for the particular elements of an event) and relational memory (i.e., memory for the relationships between elements). Behaviorally, we observed that concussion history did not significantly affect behavioral performance, because persons in the low and high concussion groups had equivalent performance on both memory tasks, and in addition, that concussion history was not associated with any behavioral memory measures. Despite demonstrating equivalent behavioral performance, the two groups of former players demonstrated different neural recruitment patterns during relational memory retrieval, suggesting that multiple concussions may be associated with functional inefficiencies in the relational memory network. In addition, the number of previous concussions significantly correlated with functional activity in a number of brain regions, including the medial temporal lobe and inferior parietal lobe. Our results provide important insights in understanding the long-term functional consequences of sustaining multiple sports-related concussions.

  13. Episodic Memory in Former Professional Football Players with a History of Concussion: An Event-Related Functional Neuroimaging Study

    PubMed Central

    Giovanello, Kelly S.; Guskiewicz, Kevin M.

    2013-01-01

    Abstract Previous research has demonstrated that sport-related concussions can have short-term effects on cognitive processes, but the long-term consequences are less understood and warrant more research. This study was the first to use event-related functional magnetic resonance imaging (fMRI) to examine long-term differences in neural activity during memory tasks in former athletes who have sustained multiple sport-related concussions. In an event-related fMRI study, former football players reporting multiple sport-related concussions (i.e., three or more) were compared with players who reported fewer than three concussions during a memory paradigm examining item memory (i.e., memory for the particular elements of an event) and relational memory (i.e., memory for the relationships between elements). Behaviorally, we observed that concussion history did not significantly affect behavioral performance, because persons in the low and high concussion groups had equivalent performance on both memory tasks, and in addition, that concussion history was not associated with any behavioral memory measures. Despite demonstrating equivalent behavioral performance, the two groups of former players demonstrated different neural recruitment patterns during relational memory retrieval, suggesting that multiple concussions may be associated with functional inefficiencies in the relational memory network. In addition, the number of previous concussions significantly correlated with functional activity in a number of brain regions, including the medial temporal lobe and inferior parietal lobe. Our results provide important insights in understanding the long-term functional consequences of sustaining multiple sports-related concussions. PMID:23679098

  14. Blurring emotional memories using eye movements: individual differences and speed of eye movements

    PubMed Central

    van Schie, Kevin; van Veen, Suzanne C.; Engelhard, Iris M.; Klugkist, Irene; van den Hout, Marcel A.

    2016-01-01

    Background In eye movement desensitization and reprocessing (EMDR), patients make eye movements (EM) while recalling traumatic memories. Making EM taxes working memory (WM), which leaves less resources available for imagery of the memory. This reduces memory vividness and emotionality during future recalls. WM theory predicts that individuals with small working memory capacities (WMCs) benefit more from low levels of taxing (i.e., slow EM) whereas individuals with large WMC benefit more from high levels of taxing (i.e., fast EM). Objective We experimentally examined and tested four prespecified hypotheses regarding the role of WMC and EM speed in reducing emotionality and vividness ratings: 1) EM—regardless of WMC and EM speed—are more effective compared to no dual task, 2) increasing EM speed only affects the decrease in memory ratings irrespective of WMC, 3) low-WMC individuals—compared to high-WMC individuals—benefit more from making either type of EM, 4) the EM intervention is most effective when—as predicted by WM theory—EM are adjusted to WMC. Method Undergraduates with low (n=31) or high (n=35) WMC recalled three emotional memories and rated vividness and emotionality before and after each condition (recall only, recall + slow EM, and recall + fast EM). Results Contrary to the theory, the data do not support the hypothesis that EM speed should be adjusted to WMC (hypothesis 4). However, the data show that a dual task in general is more effective in reducing memory ratings than no dual task (hypothesis 1), and that a more cognitively demanding dual task increases the intervention's effectiveness (hypothesis 2). Conclusions Although adjusting EM speed to an individual's WMC seems a straightforward clinical implication, the data do not show any indication that such a titration is helpful. PMID:27387843

  15. The representation of response effector and response location in episodic memory for newly acquired actions: evidence from retrieval-induced forgetting.

    PubMed

    Reppa, Irene; Worth, E Rhian; Greville, W James; Saunders, Jo

    2013-06-01

    Information retrieval can cause forgetting for related but non-retrieved information. Such retrieval-induced forgetting (RIF) has been previously found for semantically and episodically related information. The current study used RIF to examine whether response effector and location are encoded explicitly in action memory. Participants learned unique touchscreen responses to ten novel objects. Correct actions to each object involved left-hand or right-hand pushing of one of four possible object buttons. After learning, participants practiced two of the ten object-specific sequences. Unpracticed actions could share hand only, button only, both hand and button, or neither hand nor button, with the practiced actions. Subsequent testing showed significant RIF (in retrieval accuracy and speed measures) for actions that shared hand only, button only, or both hand and button with the practiced action. The results have implications for understanding the representations mediating episodic action memory, and for the potential of RIF as a tool for elucidating feature-based representations in this and other domains.

  16. Episodic memories as building blocks of identity processing styles and life domains satisfaction: Examining need satisfaction and need for cognitive closure in memories.

    PubMed

    Bouizegarene, Nabil; Philippe, Frederick L

    2016-01-01

    The interconnection between identity and memory is widely accepted, but the processes underlying this association remain unclear. The present study examined how specific experiential components of self-defining memories relate to identity processing styles. We also investigated whether those relationships occurred in a domain-specific manner. Participants (n = 583) completed the Identity Style Inventory-3, which we adapted to measure identity in the school and friend domains, as well as scales assessing their friend and school satisfaction. They then described a memory related to each of these domains and rated the level of need satisfaction and need for cognitive closure characterising each memory. Results from structural equation modeling revealed that need satisfaction in the school-related memory was positively associated with an informational identity style at school and with satisfaction at school, whereas need satisfaction in the friend-related memory was positively associated with an informational identity style in both the school and friend domain, and with satisfaction with friends. In addition, need for cognitive closure in both the friend- and school-related memory was associated with normative friend and school identity processing styles. These findings reveal that specific experiential components of self-defining memories are associated with certain identity processing styles. Furthermore, this relationship appears to be mostly domain-specific.

  17. Attentional interference in judgments of musical timbre: individual differences in working memory.

    PubMed

    Hall, Michael D; Blasko, Dawn G

    2005-01-01

    Researchers have shown that working memory is related to a variety of high-level cognitive processes. However, the results of recent research have suggested that may be because of its role in attentional control. In the present experiment, the authors investigated that hypothesis by using an attentional interference task with musical stimuli. Listeners were asked to monitor one ear for either a clarinet or violin tone and to ignore any information in the other ear. On some of the trials, they heard only one tone and on other trials, either the same instrument in both ears or different instruments. Individual differences were measured in working memory and musical experience. The results showed more attentional interference in the different-instrument condition for participants with lower working memory scores, which suggested that working memory involves the ability to control attention to inhibit irrelevant information.

  18. The effect of vertical and horizontal symmetry on memory for tactile patterns in late blind individuals.

    PubMed

    Cattaneo, Zaira; Vecchi, Tomaso; Fantino, Micaela; Herbert, Andrew M; Merabet, Lotfi B

    2013-02-01

    Visual stimuli that exhibit vertical symmetry are easier to remember than stimuli symmetric along other axes, an advantage that extends to the haptic modality as well. Critically, the vertical symmetry memory advantage has not been found in early blind individuals, despite their overall superior memory, as compared with sighted individuals, and the presence of an overall advantage for identifying symmetric over asymmetric patterns. The absence of the vertical axis memory advantage in the early blind may depend on their total lack of visual experience or on the effect of prolonged visual deprivation. To disentangle this issue, in this study, we measured the ability of late blind individuals to remember tactile spatial patterns that were either vertically or horizontally symmetric or asymmetric. Late blind participants showed better memory performance for symmetric patterns. An additional advantage for the vertical axis of symmetry over the horizontal one was reported, but only for patterns presented in the frontal plane. In the horizontal plane, no difference was observed between vertical and horizontal symmetric patterns, due to the latter being recalled particularly well. These results are discussed in terms of the influence of the spatial reference frame adopted during exploration. Overall, our data suggest that prior visual experience is sufficient to drive the vertical symmetry memory advantage, at least when an external reference frame based on geocentric cues (i.e., gravity) is adopted.

  19. Working memory demands of aided augmentative and alternative communication for individuals with developmental disabilities.

    PubMed

    Thistle, Jennifer J; Wilkinson, Krista M

    2013-09-01

    When speech is not functional to meet some or all of an individual's communication needs, aided augmentative and alternative communication (AAC) systems are often implemented. Although aided AAC systems offer some advantages over speech, they also impose some unique demands, especially on working memory, which is commonly defined as the cognitive system by which individuals maintain and manipulate information while completing tasks. For instance, the presence of an external aided AAC device containing arrays of symbols, not all of which are visible simultaneously, presents multiple working memory demands: individuals must maintain the target concepts in mind, all the while (a) navigating through multiple pages, (b) remembering the appropriate or most efficient navigation path, (c) locating the target symbols within the array once the host page has been located, and (d) inhibiting responses to potentially interesting distracters throughout the process. Each of these task demands involves one or more working memory operations that have been identified and studied extensively in research in the cognitive sciences. Failure to acknowledge or understand how working memory might interact with AAC use may place unintentional barriers to effective AAC interventions. This paper explores current information about working memory operations and highlights some of the most relevant issues that warrant further direct study.

  20. Low episodic memory performance in cognitively normal elderly subjects is associated with increased posterior cingulate gray matter N-acetylaspartate: a (1)H MRSI study at 7 Tesla.

    PubMed

    Schreiner, Simon J; Kirchner, Thomas; Wyss, Michael; Van Bergen, Jiri M G; Quevenco, Frances C; Steininger, Stefanie C; Griffith, Erica Y; Meier, Irene; Michels, Lars; Gietl, Anton F; Leh, Sandra E; Brickman, Adam M; Hock, Christoph; Nitsch, Roger M; Pruessmann, Klaas P; Henning, Anke; Unschuld, Paul G

    2016-12-01

    Low episodic memory performance characterizes elderly subjects at increased risk for Alzheimer's disease (AD) and may reflect neuronal dysfunction within the posterior cingulate cortex and precuneus (PCP) region. To investigate a potential association between cerebral neurometabolism and low episodic memory in the absence of cognitive impairment, tissue-specific magnetic resonance spectroscopic imaging at ultrahigh field strength of 7 Tesla was used to investigate the PCP region in a healthy elderly study population (n = 30, age 70 ± 5.7 years, Mini-Mental State Examination 29.4 ± 4.1). The Verbal Learning and Memory Test (VLMT) was administered as part of a neuropsychological battery for assessment of episodic memory performance. Significant differences between PCP gray and white matter could be observed for glutamate-glutamine (p = 0.001), choline (p = 0.01), and myo-inositol (p = 0.02). Low Verbal Learning and Memory Test performance was associated with high N-acetylaspartate in PCP gray matter (p = 0.01) but not in PCP white matter. Our data suggest that subtle decreases in episodic memory performance in the elderly may be associated with increased levels of N-acetylaspartate as a reflection of increased mitochondrial energy capacity in PCP gray matter.

  1. Autobiographical episodic memory-based training for the treatment of mood, anxiety and stress-related disorders: A systematic review and meta-analysis.

    PubMed

    Hitchcock, Caitlin; Werner-Seidler, Aliza; Blackwell, Simon E; Dalgleish, Tim

    2017-03-01

    We review evidence for training programmes that manipulate autobiographical processing in order to treat mood, anxiety, and stress-related disorders, using the GRADE criteria to judge evidence quality. We also position the current status of this research within the UK Medical Research Council's (2000, 2008) framework for the development of novel interventions. A literature search according to PRISMA guidelines identified 15 studies that compared an autobiographical episodic memory-based training (AET) programme to a control condition, in samples with a clinician-derived diagnosis. Identified AET programmes included Memory Specificity Training (Raes, Williams, & Hermans, 2009), concreteness training (Watkins, Baeyens, & Read, 2009), Competitive Memory Training (Korrelboom, van der Weele, Gjaltema, & Hoogstraten, 2009), imagery-based training of future autobiographical episodes (Blackwell & Holmes, 2010), and life review/reminiscence therapy (Arean et al., 1993). Cohen's d was calculated for between-group differences in symptom change from pre- to post-intervention and to follow-up. We also completed meta-analyses for programmes evaluated across multiple studies, and for the overall effect of AET as a treatment approach. Results demonstrated promising evidence for AET in the treatment of depression (d=0.32), however effect sizes varied substantially (from -0.18 to 1.91) across the different training protocols. Currently, research on AET for the treatment of anxiety and stress-related disorders is not yet at a stage to draw firm conclusions regarding efficacy as there were only a very small number of studies which met inclusion criteria. AET offers a potential avenue through which low-intensity treatment for affective disturbance might be offered.

  2. Fusing Functional MRI and Diffusion Tensor Imaging Measures of Brain Function and Structure to Predict Working Memory and Processing Speed Performance among Inter-episode Bipolar Patients.

    PubMed

    McKenna, Benjamin S; Theilmann, Rebecca J; Sutherland, Ashley N; Eyler, Lisa T

    2015-05-01

    Evidence for abnormal brain function as measured with diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) and cognitive dysfunction have been observed in inter-episode bipolar disorder (BD) patients. We aimed to create a joint statistical model of white matter integrity and functional response measures in explaining differences in working memory and processing speed among BD patients. Medicated inter-episode BD (n=26; age=45.2±10.1 years) and healthy comparison (HC; n=36; age=46.3±11.5 years) participants completed 51-direction DTI and fMRI while performing a working memory task. Participants also completed a processing speed test. Tract-based spatial statistics identified common white matter tracts where fractional anisotropy was calculated from atlas-defined regions of interest. Brain responses within regions of interest activation clusters were also calculated. Least angle regression was used to fuse fMRI and DTI data to select the best joint neuroimaging predictors of cognitive performance for each group. While there was overlap between groups in which regions were most related to cognitive performance, some relationships differed between groups. For working memory accuracy, BD-specific predictors included bilateral dorsolateral prefrontal cortex from fMRI, splenium of the corpus callosum, left uncinate fasciculus, and bilateral superior longitudinal fasciculi from DTI. For processing speed, the genu and splenium of the corpus callosum and right superior longitudinal fasciculus from DTI were significant predictors of cognitive performance selectively for BD patients. BD patients demonstrated unique brain-cognition relationships compared to HC. These findings are a first step in discovering how interactions of structural and functional brain abnormalities contribute to cognitive impairments in BD.

  3. Pharmacogenetic associations of the type-3 metabotropic glutamate receptor (GRM3) gene with working memory and clinical symptom response to antipsychotics in first-episode schizophrenia

    PubMed Central

    Reilly, James L.; Harris, Margret S. H.; Patel, Shitalben R.; Kittles, Rick; Badner, Judith A.; Prasad, Konasale M.; Nimgaonkar, Vishwajit L.; Keshavan, Matcheri S.; Sweeney, John A.

    2014-01-01

    Rationale Type-3 metabotropic glutamate receptor gene (GRM3) single nucleotide polymorphisms (SNPs) have been associated with cognitive performance and prefrontal cortex brain activity in chronically treated schizophrenia patients. Whether these SNPs are associated with cognitive and symptom response to antipsychotic therapy has not been extensively evaluated. Objectives The aim of the study was to examine pharmacogenetic relationships between GRM3 and selected variants in relevant dopamine genes with changes in spatial working memory and clinical symptoms after treatment. Methods Sixty-one untreated first-episode schizophrenia patients were assessed before and after 6 weeks of antipsychotic pharmacotherapy, primarily consisting of risperidone. Patients’ level of cognitive performance on a spatial working memory task was assessed with a translational oculomotor paradigm. Changes after treatment in cognitive and clinical measures were examined in relationship to genetic polymorphisms in the GRM3, COMT, and DRD2/ANKK1 gene regions. Results Spatial working memory performance worsened after antipsychotic treatment. This worsening was associated with GRM3 rs1468412, with the genetic subgroup of patients known to have altered glutamate activity having greater adverse changes in working memory performance after antipsychotic treatment. Negative symptom improvement was associated with GRM3 rs6465084. There were no pharmacogenetic associations between DRD2/ANKK1 and COMT with working memory changes or symptom response to treatment. Conclusions These findings suggest important pharmacogenetic relationships between GRM3 variants and changes in cognition and symptom response with exposure to antipsychotics. This information may be useful in identifying patients susceptible to adverse cognitive outcomes associated with antipsychotic treatment and suggest that glutamatergic mechanisms contribute to such effects. PMID:25096017

  4. Effects of Presentation Mode on Veridical and False Memory in Individuals with Intellectual Disability

    ERIC Educational Resources Information Center

    Carlin, Michael; Toglia, Michael P.; Belmonte, Colleen; DiMeglio, Chiara

    2012-01-01

    In the present study the effects of visual, auditory, and audio-visual presentation formats on memory for thematically constructed lists were assessed in individuals with intellectual disability and mental age-matched children. The auditory recognition test included target items, unrelated foils, and two types of semantic lures: critical related…

  5. Spatial-Sequential and Spatial-Simultaneous Working Memory in Individuals with Williams Syndrome

    ERIC Educational Resources Information Center

    Lanfranchi, Silvia; De Mori, Letizia; Mammarella, Irene C.; Carretti, Barbara; Vianello, Renzo

    2015-01-01

    The aim of the present study was to compare visuospatial working memory performance in 18 individuals with Williams syndrome (WS) and 18 typically developing (TD) children matched for nonverbal mental age. Two aspects were considered: task presentation format (i.e., spatial-sequential or spatial-simultaneous), and level of attentional control…

  6. On the Role of Individual Items in Recognition Memory and Metacognition: Challenges for Signal Detection Theory

    ERIC Educational Resources Information Center

    Busey, Thomas A.; Arici, Anne

    2009-01-01

    The authors tested the role of individual items in recognition memory using a forced-choice paradigm with face stimuli. They constructed distractor stimuli using morphing procedures that were similar to two parent faces and then compared a studied morph against an unstudied morph that was similar to two studied parents. The similarity of the…

  7. Memory Failures Appraisal in Younger and Older Adults: Role of Individual Difference and Event Outcome Variables

    ERIC Educational Resources Information Center

    Cherry, Katie E.; Brigman, Susan

    2005-01-01

    The authors examined the role of individual difference and event outcome variables in younger and older adults' memory failures appraisal. Participants read vignettes that described fictitious younger characters (in their 20s-30s) or older characters (in their 60s-70s) who had experienced a minor or severe consequence of their forgetfulness. The…

  8. Neural Correlates of Individual Differences in Infant Visual Attention and Recognition Memory

    ERIC Educational Resources Information Center

    Reynolds, Greg D.; Guy, Maggie W.; Zhang, Dantong

    2011-01-01

    Past studies have identified individual differences in infant visual attention based upon peak look duration during initial exposure to a stimulus. Colombo and colleagues found that infants that demonstrate brief visual fixations (i.e., short lookers) during familiarization are more likely to demonstrate evidence of recognition memory during…

  9. Problematic alcohol use among individuals with HIV: relations with everyday memory functioning and HIV symptom severity.

    PubMed

    Heinz, Adrienne J; Fogler, Kethera A; Newcomb, Michael E; Trafton, Jodie A; Bonn-Miller, Marcel O

    2014-07-01

    Problematic alcohol use has been shown to negatively impact cognitive functions germane to achieving optimal HIV health outcomes. The present study, a secondary data analysis, examined the impact of problematic alcohol use on aspects of everyday memory functioning in a sample of 172 HIV-infected individuals (22 % female; Mage = 48.37 years, SD = 8.64; 39 % Black/non-Hispanic). Additionally, we tested whether self-reported memory functioning explained the relation between problematic alcohol use and HIV symptom severity. Results indicated that problematic patterns of alcohol use were associated with lower total memory functioning, retrieval (e.g., recall-difficulty) and memory for activity (e.g., what you did yesterday) and greater HIV symptom severity. Memory functioning mediated the relation between problematic alcohol use and HIV symptom severity. However, the direction of this relation was unclear as HIV symptom severity also mediated the relation between problematic alcohol use and memory functioning. Findings highlight the importance of integrated care for HIV and alcohol use disorders and suggest that routine alcohol and cognitive screenings may bolster health outcomes among this vulnerable population.

  10. Endogenous cortisol elevations are related to memory facilitation only in individuals who are emotionally aroused.

    PubMed

    Abercrombie, Heather C; Speck, Nicole S; Monticelli, Roxanne M

    2006-02-01

    Animal research suggests that cortisol facilitates memory only during emotional arousal. Thus, we predicted that during mild emotion and stress elicitation, endogenous cortisol elevations would predict memory facilitation only in individuals who report high stress-related negative affect. Thirty-one men viewed neutral and emotional stimuli and then were subjected to a public speaking stress task. Area under the curve for overall cortisol output during the speech was computed. Negative affect (NA) using the PANAS state version [Watson, D., Clark, L.A., Tellegen, A., 1988. Development and validation of brief measures of positive and negative affect: the PANAS scales. J. Personality Social Psychol. 54, 1063-1070.] was measured at baseline and immediately after the speech stressor. Cortisol output during the speech and change in NA interactively predicted free recall performance assessed 2 days later. This interaction was due to the finding that higher cortisol output was related to memory facilitation only in subjects who reported high stress-related negative affect (i.e. only in those individuals whose NA increased compared to baseline). This relation was especially prominent for recall of unpleasant pictures. Subjects who reported low stress-related negative affect, no relation was found between cortisol output during the speech and memory performance. Thus, the relation between cortisol and memory appears to depend on an increase in negative affect related to stress.

  11. Hierarchical organization in visual working memory: From global ensemble to individual object structure.

    PubMed

    Nie, Qi-Yang; Müller, Hermann J; Conci, Markus

    2017-02-01

    When remembering a natural scene, both detailed information about specific objects and summary representations such as the gist of a scene are encoded. However, formal models of change detection that are used to estimate working memory capacity, typically assume observers simply encode and maintain memory representations that are treated independently from one another without considering the (hierarchical) object or scene structure. To overcome this limitation, we present a hierarchical variant of the change detection task that attempts to formalize the role of object structure, thus, allowing for richer, more graded memory representations. We demonstrate that detection of a global-object change precedes local-object changes of hierarchical shapes to a large extent. Moreover, when systematically varying object repetitions between individual items at a global or a local level, memory performance declines mainly for repeated global objects, but not for repeated local objects, which suggests that ensemble (i.e., summary) representations are likewise biased toward a global level. In addition, this global memory precedence effect is shown to be independent from encoding durations, and mostly cannot be attributed to differences in saliency or shape discriminability at global/local object levels. This pattern of results is suggestive of a global/local difference occurring primarily during memory maintenance. Altogether, these findings challenge visual-working-memory (vWM) models that propose that a fixed number of objects can be remembered regardless of the individual object structure. Instead, our results support a hierarchical model that emphasizes the role for structured representations among objects in vWM.

  12. Alzheimer's Disease Can Spare Local Metacognition Despite Global Anosognosia: Revisiting the Confidence-Accuracy Relationship in Episodic Memory

    ERIC Educational Resources Information Center

    Gallo, David A.; Cramer, Stefanie J.; Wong, Jessica T.; Bennett, David A.

    2012-01-01

    Alzheimer's disease (AD) can impair metacognition in addition to more basic cognitive functions like memory. However, while global metacognitive inaccuracies are well documented (i.e., low deficit awareness, or anosognosia), the evidence is mixed regarding the effects of AD on local or task-based metacognitive judgments. Here we investigated local…

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

    ERIC Educational Resources Information Center

    Naito, Mika; Suzuki, Toshiko

    2011-01-01

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

  14. Mediation of episodic memory performance by the executive function network in patients with amnestic mild cognitive impairment: a resting-state functional MRI study

    PubMed Central

    Yuan, Baoyu; Chen, Jiu; Gong, Liang; Shu, Hao; Liao, Wenxiang; Wang, Zan; Liu, Duan; Xie, Chunming; Zhang, Zhijun

    2016-01-01

    Deficits in episodic memory (EM) are a hallmark clinical symptom of patients with amnestic mild cognitive impairment (aMCI). Impairments in executive function (EF) are widely considered to exacerbate memory deficits and to increase the risk of conversion from aMCI to Alzheimer's disease (AD). However, the specific mechanisms underlying the interaction between executive dysfunction and memory deficits in aMCI patients remain unclear. Thus, the present study utilized resting-state functional magnetic resonance imaging (fMRI) scans of the EF network and the EM network to investigate this relationship in 79 aMCI patients and 119 healthy controls (HC). The seeds were obtained from the results of a regional homogeneity (ReHo) analysis. Functional connectivity (FC) within the EM network was determined using a seed in the right retrosplenial cortex (RSC), and FC within EF network was assessed using seeds in the right dorsolateral prefrontal cortex (DLPFC). There was a significant negative correlation between EM scores and EF scores in both the aMCI and HC groups. Compared to the HC group, aMCI patients had reduced right RSC connectivity but enhanced right DLPFC connectivity. The overlapping brain regions between the EM and EF networks were associated with FC in the right inferior parietal lobule (IPL) in the right RSC network, and in the bilateral middle cingulate cortex (MCC) and left IPL in the right DLPFC network. A mediation analysis revealed that the EF network had an indirect positive effect on EM performance in the aMCI patients. The present findings provide new insights into the neural mechanisms underlying the interaction between impaired EF and memory deficits in aMCI patients and suggest that the EF network may mediate EM performance in this population. PMID:27589839

  15. Depressive Symptoms Are More Strongly Related to Executive Functioning and Episodic Memory Among African American compared with Non-Hispanic White Older Adults

    PubMed Central

    Zahodne, Laura B.; Nowinski, Cindy J.; Gershon, Richard C.; Manly, Jennifer J.

    2014-01-01

    We examined whether the reserve capacity model can be extended to cognitive outcomes among older African Americans. Two hundred and ninety-two non-Hispanic Whites and 37 African Americans over age 54 participated in the normative study for the NIH Toolbox for the Assessment of Neurological and Behavioral Function. Multiple-group path analysis showed that associations between depressive symptoms and cognition differed by race, independent of age, education, reading level, income, health, and recruitment site. Depressive symptoms were associated with slowed processing speed among Whites and worse task-switching, inhibition, and episodic memory among African Americans. African Americans may be more vulnerable to negative effects of depression on cognition than non-Hispanic Whites. Further research is needed to explicate the psychological and neurobiological underpinnings of this greater vulnerability. PMID:25280795

  16. The effect of interference on temporal order memory in individuals with Parkinson's disease.

    PubMed

    DeFord, Nicole E; Landy, Kelly M; Pirogovsky-Turk, Eva; Van Etten, Emily J; Graves, Lisa V; Salmon, David P; Filoteo, J Vincent; Gilbert, Paul E

    2016-08-01

    Memory for the temporal order of items or events in a sequence has been shown to be impaired in older adults and individuals with Parkinson's disease (PD). The present study examined the effects of high and low interference on temporal order memory in individuals diagnosed with PD (n=20) and demographically similar healthy older adults (n=20) utilizing a computerized task used in previously published studies. During the sample phase of each trial, a series of eight circles were randomly presented one at a time in eight different spatial locations. Participants were instructed to remember the sequence in which the circles appeared in the locations. During the choice phase, participants were presented with two circles in two different locations and were asked to indicate which circle appeared earliest in the sample phase sequence. The two circles were separated by one of four possible temporal separation lags (0, 2, 4, and 6), defined as the number of circles occurring in the sample phase sequence between the two choice phase circles. Shorter temporal lags (e.g., 0 and 2 lags) were hypothesized to result in higher interference compared to longer temporal lags (e.g., 4 and 6 lags). The results demonstrated that on trials involving high interference, no differences were found between the two groups. However, healthy older adults significantly outperformed individuals with PD (p<0.05) on trials involving low interference. Although differences were found between the PD and healthy older adult groups, both groups significantly improved on low interference trials compared to high interference trials (p<0.001). The findings indicate that temporal order memory improves in healthy older adults and individuals with PD when interference is reduced. However, individuals with PD demonstrated poorer temporal order memory even with less interference. Therefore, temporal order memory is differentially affected by interference in healthy older adults and individuals with PD. Given

  17. Differential Constraints on the Working Memory and Reading Abilities of Individuals with Learning Difficulties and Typically Developing Children

    ERIC Educational Resources Information Center

    Bayliss, Donna M.; Jarrold, Christopher; Baddeley, Alan D.; Leigh, Eleanor

    2005-01-01

    This study examined the factors that constrain the working memory span performance and reading ability of individuals with generalized learning difficulties. In the study, 50 individuals with learning difficulties (LD) and 50 typically developing children (TD) matched for reading age completed two working memory span tasks. Participants also…

  18. Immediate List Recall as a Measure of Short-Term Episodic Memory: Insights from the Serial Position Effect and Item Response Theory

    PubMed Central

    Gavett, Brandon E.; Horwitz, Julie E.

    2012-01-01

    The serial position effect shows that two interrelated cognitive processes underlie immediate recall of a supraspan word list. The current study used item response theory (IRT) methods to determine whether the serial position effect poses a threat to the construct validity of immediate list recall as a measure of verbal episodic memory. Archival data were obtained from a national sample of 4,212 volunteers aged 28–84 in the Midlife Development in the United States study. Telephone assessment yielded item-level data for a single immediate recall trial of the Rey Auditory Verbal Learning Test (RAVLT). Two parameter logistic IRT procedures were used to estimate item parameters and the Q1 statistic was used to evaluate item fit. A two-dimensional model better fit the data than a unidimensional model, supporting the notion that list recall is influenced by two underlying cognitive processes. IRT analyses revealed that 4 of the 15 RAVLT items (1, 12, 14, and 15) were misfit (p < .05). Item characteristic curves for items 14 and 15 decreased monotonically, implying an inverse relationship between the ability level and the probability of recall. Elimination of the four misfit items provided better fit to the data and met necessary IRT assumptions. Performance on a supraspan list learning test is influenced by multiple cognitive abilities; failure to account for the serial position of words decreases the construct validity of the test as a measure of episodic memory and may provide misleading results. IRT methods can ameliorate these problems and improve construct validity. PMID:22138320

  19. Memory bias for schema-related stimuli in individuals with bulimia nervosa.

    PubMed

    Legenbauer, Tanja; Maul, Bärbel; Rühl, Ilka; Kleinstäuber, Maria; Hiller, Wolfgang

    2010-03-01

    This study investigates whether individuals with bulimia nervosa (BN) have a memory bias in relation to explicit memory (cued and free recall vs. verbal and pictorial recognition tasks). Twenty-five participants diagnosed with BN and 27 normal controls (NC) were exposed to body-related, food-related, and neutral TV commercials, and then recall and recognition rates were assessed. Poorer recognition and recall of body-related stimuli was found for BN in comparison to NC, suggesting a memory bias. Results are discussed in relation to previous studies, along with suggestions as to how future studies can gain more insight into dysfunctions in information processing that can lead to the maintenance of eating disorders.

  20. Attentional guidance by working memory differs by paradigm: an individual-differences approach.

    PubMed

    Dowd, Emma Wu; Kiyonaga, Anastasia; Egner, Tobias; Mitroff, Stephen R

    2015-04-01

    The contents of working memory (WM) have been repeatedly found to guide the allocation of visual attention; in a dual-task paradigm that combines WM and visual search, actively holding an item in WM biases visual attention towards memory-matching items during search (e.g., Soto et al., Journal of Experimental Psychology: Human Perception and Performance, 31(2), 248-261, 2005). A key debate is whether such memory-based attentional guidance is automatic or under strategic control. Generally, two distinct task paradigms have been employed to assess memory-based guidance, one demonstrating that attention is involuntarily captured by memory-matching stimuli even at a cost to search performance (Soto et al., 2005), and one demonstrating that participants can strategically avoid memory-matching distractors to facilitate search performance (Woodman & Luck, Journal of Experimental Psychology: Human Perception and Performance, 33(2), 363-377, 2007). The current study utilized an individual-differences approach to examine why the different paradigms--which presumably tap into the same attentional construct--might support contrasting interpretations. Participants completed a battery of cognitive tasks, including two types of attentional guidance paradigms (see Soto et al., 2005; Woodman & Luck, 2007), a visual WM task, and an operation span task, as well as attention-related self-report assessments. Performance on the two attentional guidance paradigms did not correlate. Subsequent exploratory regression analyses revealed that memory-based guidance in each task was differentially predicted by visual WM capacity for one paradigm, and by attention-related assessment scores for the other paradigm. The current results suggest that these two paradigms--which have previously produced contrasting patterns of performance--may probe distinct aspects of attentional guidance.

  1. Neural activity in the hippocampus predicts individual visual short-term memory capacity.

    PubMed

    von Allmen, David Yoh; Wurmitzer, Karoline; Martin, Ernst; Klaver, Peter

    2013-07-01

    Although the hippocampus had been traditionally thought to be exclusively involved in long-term memory, recent studies raised controversial explanations why hippocampal activity emerged during short-term memory tasks. For example, it has been argued that long-term memory processes might contribute to performance within a short-term memory paradigm when memory capacity has been exceeded. It is still unclear, though, whether neural activity in the hippocampus predicts visual short-term memory (VSTM) performance. To investigate this question, we measured BOLD activity in 21 healthy adults (age range 19-27 yr, nine males) while they performed a match-to-sample task requiring processing of object-location associations (delay period  =  900 ms; set size conditions 1, 2, 4, and 6). Based on individual memory capacity (estimated by Cowan's K-formula), two performance groups were formed (high and low performers). Within whole brain analyses, we found a robust main effect of "set size" in the posterior parietal cortex (PPC). In line with a "set size × group" interaction in the hippocampus, a subsequent Finite Impulse Response (FIR) analysis revealed divergent hippocampal activation patterns between performance groups: Low performers (mean capacity  =  3.63) elicited increased neural activity at set size two, followed by a drop in activity at set sizes four and six, whereas high performers (mean capacity  =  5.19) showed an incremental activity increase with larger set size (maximal activation at set size six). Our data demonstrated that performance-related neural activity in the hippocampus emerged below capacity limit. In conclusion, we suggest that hippocampal activity reflected successful processing of object-location associations in VSTM. Neural activity in the PPC might have been involved in attentional updating.

  2. Individual Differences in Eye-Movements During Reading: Working Memory and Speed-of-Processing Effects.

    PubMed

    Traxler, Matthew J; Long, Debra L; Tooley, Kristen M; Johns, Clinton L; Zirnstein, Megan; Jonathan, Eunike

    Theories of eye-movement control in reading should ultimately describe how differences in knowledge and cognitive abilities affect reading and comprehension. Current mathematical models of eye-movement control do not yet incorporate individual differences as a source of variation in reading, although developmental and group-difference effects have been studied. These models nonetheless provide an excellent foundation for describing and explaining how and why patterns of eye-movements differ across readers (e.g., Rayner, Chace, & Ashby, 2006). Our focus in this article is on two aspects of individual variation: global processing speed (e.g., Salthouse, 1996) and working-memory capacity (e.g., Just & Carpenter, 1992). Using Hierarchical Linear Modeling (HLM) (Raudenbush & Bryk, 2001), we tested the extent to which overall reading speed and working-memory capacity moderate the degree to which syntactic and semantic information affect fixation times. Previous published data (Traxler et al., 2005) showed that working memory capacity and syntactic complexity interacted to determine fixation times in an eye-movement monitoring experiment. In a new set of models based on this same data set, we found that working-memory capacity interacted with sentence-characteristic variables only when processing speed was not included in the model. We interpret these findings with respect to current accounts of sentence processing and suggest how they might be incorporated into eye-movement control models.

  3. Individual Differences in Eye-Movements During Reading: Working Memory and Speed-of-Processing Effects

    PubMed Central

    Traxler, Matthew J.; Long, Debra L.; Tooley, Kristen M.; Johns, Clinton L.; Zirnstein, Megan; Jonathan, Eunike

    2015-01-01

    Theories of eye-movement control in reading should ultimately describe how differences in knowledge and cognitive abilities affect reading and comprehension. Current mathematical models of eye-movement control do not yet incorporate individual differences as a source of variation in reading, although developmental and group-difference effects have been studied. These models nonetheless provide an excellent foundation for describing and explaining how and why patterns of eye-movements differ across readers (e.g., Rayner, Chace, & Ashby, 2006). Our focus in this article is on two aspects of individual variation: global processing speed (e.g., Salthouse, 1996) and working-memory</