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Resting-state network research is extremely influential, yet the functions of many networks remain unknown. In part, this is due to typical (e.g., univariate) analyses testing the function of individual regions and not the full set of co-activated regions that form a network. Connectivity is dynamic and the function of a region may change based on its current connections. Therefore, determining the function of a network requires assessment at the network-level. Yet popular theories implicating the default mode network (DMN) in episodic memory and social cognition, rest principally upon analyses performed at the level of individual brain regions. Here we use independent component analysis to formally test the role of the DMN in episodic and social processing at the network level. As well as an episodic retrieval task, two independent datasets were employed to assess DMN function across the breadth of social cognition; a person knowledge judgement and a theory of mind task. Each task dataset was separated into networks of co-activated regions. In each, the co-activated DMN, was identified through comparison to an a priori template and its relation to the task model assessed. This co-activated DMN did not show greater activity in episodic or social tasks than high-level baseline conditions. Thus, no evidence was found to support hypotheses that the co-activated DMN is involved in explicit episodic or social processing tasks at a network-level. The networks associated with these processes are described. Implications for prior univariate findings and the functional significance of the co-activated DMN are considered.

BackgroundWhile neuroimaging has provided insights into the formation of episodic memories in relation to voluntary memory recall, less is known about neural mechanisms that cause memories to occur involuntarily, for example, as intrusive memories of trauma. Here, we investigated brain activity shortly after viewing distressing events as a function of whether memories for those events later intruded involuntarily. The postencoding period is particularly important because it is a period when clinical interventions could be applied.MethodsA total of 32 healthy volunteers underwent functional magnetic resonance imaging while viewing distressing film clips, interspersed with 5 minutes of awake (postencoding) rest. Voluntary memories of the films were assessed using free recall and verbal and visual recognition tests after a week, while intrusive (involuntary) memories were recorded in a diary throughout that week.ResultsWhen analyzing functional magnetic resonance imaging responses related to watching the films, we replicated findings that those “hotspots” (salient moments within the films) that would later become intrusive memories elicited higher activation in parts of the brain’s salience network. Surprisingly, while the postencoding persistence of multivoxel correlation structures associated with entire film clips predicted subsequent voluntary recall, there was no evidence that they predicted subsequent intrusions.ConclusionsResults replicate findings regarding the formation of intrusive memories during encoding and extend findings regarding the consolidation of information in postencoding rest in relation to voluntary memory. While we provided a first step using a naturalistic paradigm, further research is needed to elucidate the role of postencoding neural processes in the development of intrusive memories.

We show that the intention to remember information substantially improves recall of that information when maintained in working memory (WM), whereas it does not have the same effect on maintenance in episodic long-term memory (LTM). In eight experiments, participants processed lists of words according to a semantic orienting task in three instruction conditions: to remember, to forget, or an incidental-memory baseline with no instruction. The first two experiments showed better memory for intentional remembering compared to incidental memory for a typical test of WM, but not for a typical test of episodic LTM. The subsequent six experiments determined which of three variables distinguishing typical WM and episodic-LTM tests-delay of test, list length, and proactive interference-are responsible for this difference. The intention to remember improved free-recall performance for short lists (close to the capacity limit of WM), most strongly when tested immediately, and only in the presence of proactive interference. This result supports a functional distinction between WM and episodic LTM: Whereas episodic LTM keeps a nonselective record of experiences for future use, WM holds selectively only the information relevant for the current goal. In addition, we found a beneficial effect of intentional remembering on memory for the list position of words, which was obtained for longer lists and regardless of the delay of testing, probably reflecting episodic LTM. The instruction to forget had no effect compared to the incidental baseline, questioning the assumption of a targeted forgetting process on memory. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

For over a century, stability of spatial context across related episodes has been considered a source of memory interference, impairing memory retrieval. However, contemporary memory integration theory generates a diametrically opposite prediction. Here, we aimed to resolve this discrepancy by manipulating local context similarity across temporally disparate but related episodes, and testing the direction and underlying mechanisms of memory change. A series of experiments show that contextual stability produces memory integration and marked reciprocal strengthening. Variable context, conversely, seemed to result in competition such that new memories become enhanced at the expense of original memories. Interestingly, these patterns were virtually inverted in an additional experiment where context was reinstated during recall. These observations (i) identify contextual similarity across original and new memories as an important determinant in the volatility of memory, (ii) present a challenge to classic and modern theories on episodic memory change, and (iii) indicate that sensitivity of context-induced memory changes to retrieval conditions may reconcile paradoxical predictions of interference and integration theory.

Our recollections of past experiences can vary in both the number of specific event details accessible from memory and the precision with which such details are reconstructed. Prior neuroimaging evidence suggests the success and precision of episodic recollection to rely on distinct neural substrates during memory retrieval. In contrast, the specific encoding mechanisms supporting later memory precision, and whether they differ from those underlying successful memory formation in general, are currently unknown. Here, we combined continuous measures of memory retrieval with model-based analyses of behavioral and neuroimaging data to tease apart the encoding correlates of successful memory formation and mnemonic precision. In the MRI scanner, participants encoded object-scene displays and later reconstructed features of studied objects using a continuous scale. We observed overlapping encoding activity in inferior prefrontal and posterior perceptual regions to predict both which object features were later remembered versus forgotten and the precision with which they were reconstructed from memory. In contrast, hippocampal encoding activity significantly predicted the precision, but not overall success, of subsequent memory retrieval. The current results align with theoretical accounts proposing the hippocampus to be critical for representation of high-fidelity associative information and suggest a contribution of shared cortical encoding mechanisms to the formation of both accessible and precise memory representations.

Whilst research has largely focused on the recognition of emotional items, emotion may be a more subtle part of our surroundings and conveyed by context rather than by items. Using ERPs, we investigated which effects an arousing context during encoding may have for item-context binding and subsequent familiarity-based and recollection-based item-memory. It has been suggested that arousal could facilitate item-context bindings and by this enhance the contribution of recollection to subsequent memory judgements. Alternatively, arousal could shift attention onto central features of a scene and by this foster unitisation during encoding. This could boost the contribution of familiarity to remembering. Participants learnt neutral objects paired with ecologically highly valid emotional faces whose names later served as neutral cues during an immediate and delayed test phase. Participants identified objects faster when they had originally been studied together with emotional context faces. Items with both neutral and emotional context elicited an early frontal ERP old/new difference (200-400 ms). Neither the neurophysiological correlate for familiarity nor recollection were specific to emotionality. For the ERP correlate of recollection, we found an interaction between stimulus type and day, suggesting that this measure decreased to a larger extend on Day 2 compared with Day 1. However, we did not find direct evidence for delayed forgetting of items encoded in emotional contexts at Day 2. Emotion at encoding might make retrieval of items with emotional context more readily accessible, but we found no significant evidence that emotional context either facilitated familiarity-based or recollection-based item-memory after a delay of 24 h.

Emotions and symptoms are often overestimated in retrospective ratings, a phenomenon referred to as the "memory-experience gap." Some research has shown that this gap is less pronounced among older compared to younger adults for self-reported negative affect, but it is not known whether these age differences are evident consistently across domains of well-being and why these age differences emerge. In this study, we examined age differences in the memory-experience gap for emotional (positive and negative affect), social (loneliness), and physical (pain, fatigue) well-being. We also tested four variables that could plausibly explain age differences in the gap: (a) episodic memory and executive functioning, (b) the age-related positivity effect, (c) variability of daily experiences, and (d) socially desirable responding. Adults (n = 477) from three age groups (21-44, 45-64, 65+ years old) participated in a 21-day diary study. Participants completed daily end-of-day ratings and retrospective ratings of the same constructs over different recall periods (3, 7, 14, and 21 days). Results showed that, relative to young and middle-aged adults, older adults had a smaller memory-experience gap for negative affect and loneliness. Lower day-to-day variability partly explained why the gap was smaller for older adults. There was no evidence that the magnitude of the memory-experience gap for positive affect, pain or fatigue depended on age. We recommend that future research considers how variability in daily experiences can impact age differences in retrospective self-reports of well-being. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Self-knowledge is a type of personal semantic knowledge that concerns one’s self-image and personal identity. It has most often been operationalized as the summary of one’s personality traits (“I am a stubborn person”). Interestingly, recent studies have revealed that the neural correlates of self-knowledge can be dissociated from those of general semantic and episodic memory in young adults. However, studies of “dedifferentiation” or loss of distinctiveness of neural representations in ageing suggest that the neural correlates of self-knowledge might be less distinct from those of semantic and episodic memory in older adults. We investigated this question in an event-related potential (ERP) study with 28 young and 26 older adults while they categorised personality traits for their self-relevance (self-knowledge conditions), and their relevance to certain groups of people (general semantic condition). Participants then performed a recognition test for previously seen traits (episodic condition). The amplitude of the late positive component (LPC), associated with episodic recollection processes, differentiated the self-knowledge, general semantic, and episodic conditions in young adults, but not in older adults. However, in older adults, participants with higher composite episodic memory scores had more differentiated LPC amplitudes across experimental conditions. Moreover, consistent with the fact that age-related neural dedifferentiation may be material and region specific, in both age groups some differences between memory types were observed for the N400 component, associated with semantic processing. Taken together, these findings suggest that declarative memory subtypes are less distinct in ageing, but that the amount of differentiation varies with episodic memory function.

Patient RB has a peculiar memory impairment wherein he experiences his memories in rich contextual detail, but claims to not own them. His memories do not feel as if they happened to him. In this paper, I provide an explanatory model of RB’s phenomenology, the self-attentional model. I draw upon recent work in neuroscience on self-attentional processing and global workspace models of conscious recollection to show that RB has a self-attentional deficit that inhibits self-bias processes in broadcasting the contents of episodic memories to the global workspace. Typically, self-related contents enjoy a higher salience level than other-related contents. Elimination of bias toward self-related contents diminishes the salience of those contents to the level of other-related contents. Because the typical high salience of self-related content is necessary for the feeling of ownership, RB lacks the feeling of ownership. I also discuss potential applications of the self-attentional model to other psychopathological cases.

Episodic memories formed during infancy are rapidly forgotten, a phenomenon associated with infantile amnesia, the inability of adults to recall early-life memories. In both rats and mice, infantile memories, although not expressed, are actually stored long term in a latent form. These latent memories can be reinstated later in life by certain behavioral reminders or by artificial reactivations of neuronal ensembles activated at training. Whether the recovery of infantile memories is limited by developmental age, maternal presence, or contingency of stimuli presentation remains to be determined. Here, we show that the return of inhibitory avoidance memory in rats following a behavioral reactivation consisting of an exposure to the context (conditioned stimuli [CS]) and footshock (unconditioned stimuli [US]) given in a temporally unpaired fashion, is evident immediately after US and is limited by the developmental age at which the reactivations are presented; however, it is not influenced by maternal presence or the time interval between training and reactivation. We conclude that one limiting factor for infantile memory reinstatement is developmental age, suggesting that a brain maturation process is necessary to allow the recovery of a “lost” infantile memory.

Episodic memories can no longer be seen as the re-activation of stored experiences but are the product of an intense construction process based on a memory trace. Episodic recall is a result of a process of scenario construction. If one accepts this generative framework of episodic memory, there is still a be big gap in understanding the role of the narrative self in shaping scenario construction. Some philosophers are in principle sceptic by claiming that a narrative self cannot be more than a causally inefficacious attributed entity anyway. Thus, we first characterize a narrative self in detail and second we clarify its influential causal role in shaping our episodic memories by influencing the process of scenario construction. This happens at three stages, namely at the level of the input, the output and the process of scenario construction.

PurposeThis research evaluates (1) work situations prompting participants to recall memories of a wilderness-based leadership training program, (2) the content of such memories, and (3) the leadership attitudes and behaviors inspired by those memories.Design/methodology/approachA qualitative content analysis of semi-structured interviews was performed with 36 leaders who had participated in a wilderness leadership transformation program in the past (on average six years before).FindingsThe findings suggest that, at moments with emotional pressure and psychological stress, episodic memories of wilderness experiences have a positive influence on actual leadership style. Memories involved moments of solitude, a deep connection with nature, and peer-to-peer counseling. The interviewees regularly relived their emotion-laden wilderness experiences, acquiring direction and guidance. Simultaneously, episodic memories of nature immersion promoted an enduring transformation of their leadership styles.Research limitations/implicationsThe findings cannot be blindly generalized as referring to all leaders. The leaders in this study are a subset of leaders who are inclined towards personal growth and leadership development. It is challenging to motivate leaders unkeen on changing to achieve better leadership.Practical implicationsThis study indicates that the inclusion of emotional concepts to address the root causes of learning among leaders might be the most promising way to innovate leadership development.Originality/valueThe present study makes a novel contribution to relevant literature by examining leadership transformation through episodic remembrance of leaders' experiences in nature.

Normalmente se piensa en la percepción y la memoria como dos capacidades independientes, creyendo que la primera solo tiene influencia sobre la segunda durante la codificación. En las entrevistas autobiográficas de historia oral y memoria histórica, los entrevistados seleccionan, adaptan y completan sus recuerdos para crear diferentes versiones de ellos. En este artículo se argumenta que lo anterior es consecuencia de la naturaleza simulativa de la memoria episódica, y del empleo por los entrevistados de información perceptiva para generar y adaptar sus recuerdos a un discurso autobiográfico, buscando satisfacer un propósito comunicativo. Para ilustrar esto, se analizan tres factores contextuales que influyen sobre la construcción del recuerdo en una entrevista autobiográfica (objetivo comunicativo, idioma de comunicación e interacción emocional), mostrando que, en este tipo de recuperación, memoria y percepción contribuyen simultáneamente a construir simulaciones de eventos que se adaptan en tiempo real al contexto donde ocurre la evocación.

Music listening provides one of the most significant abstract rewards for humans because hearing music activates the dopaminergic mesolimbic system. Given the strong link between reward, dopamine, and memory, we aimed here to investigate the hypothesis that dopamine-dependent musical reward can drive memory improvements. Twenty-nine healthy participants of both sexes provided reward ratings of unfamiliar musical excerpts that had to be remembered following a consolidation period under three separate conditions: after the ingestion of a dopaminergic antagonist, a dopaminergic precursor, or a placebo. Linear mixed modeling of the intervention data showed that the effect of reward on memory-i.e., the greater the reward experienced while listening to the musical excerpts, the better the memory recollection performance-was modulated by both dopaminergic signaling and individual differences in reward processing. Greater pleasure was consistently associated with better memory outcomes in participants with high sensitivity to musical reward, but this effect was lost when dopaminergic signaling was disrupted in participants with average or low musical hedonia. Our work highlights the flexibility of the human dopaminergic system, which can enhance memory formation not only through explicit and/or primary reinforcers but also via abstract and aesthetic rewards such as music.

Autistic people have difficulties recalling episodic memories, including retrieving fewer or less specific and detailed memories compared to typically developing people. However, the ability to effectively recall episodic memories is crucial in many real-world contexts, such as the criminal justice system, medical consultations, and employment interviews. Autistic people’s episodic memory difficulties are most apparent when open, unsupportive questions are used. The ‘Task Support Hypothesis’ posits that autistic people can recall as much information as typically developing people with more supportive questioning. Alongside problems retrieving episodic memories, autistic people also experience difficulties with executive functioning, theory of mind, and expressive language. The current study aimed to assess the impact of these abilities on recall in two previous studies by the authors that compared autistic and typically developing adults on recall specificity in police, healthcare, and employment interviews, and recall quality in employment interviews under unsupported and supported questioning. Under unsupported questioning only, autistic adults’ episodic autobiographical memory recall specificity was predicted by expressive language, whereas for the typically developing group, only theory of mind was a significant predictor. No other predictors were significant across the study. Implications for the task support hypothesis are discussed. Lay abstract Autistic people have difficulties recalling episodic memories (memories of specific events) compared to typically developing people. However, being able to effectively recall such memories is important in many real-world situations, for example, in police interviews, during medical consultations, and in employment interviews. Autistic people’s episodic memory difficulties are most noticeable when they are responding to open, unsupportive questions. However, the ‘Task Support Hypothesis’ indicates that autistic people are able to recall as much information as typically developing people, as long as they are asked more supportive questions. Autistic people also experience difficulties with executive functioning (cognitive abilities which allow us to plan, hold information in mind, inhibit interruptions, etc.), theory of mind (the ability to understand others’ perspectives and intentions), and spoken language. The current study aimed to investigate the impact of these cognitive abilities on memory recall in two previous studies which compared autistic and typically developing adults on how specific their recall was in police, healthcare, and employment interviews, and the quality of responses during an employment interview when both unsupportive and supportive questioning was used. The results show that while typically developing people may rely on theory of mind abilities, autistic people may rely more on language abilities when performing in interviews, potentially to compensate for their episodic memory difficulties, and that this effect is most apparent during more unsupportive recall (e.g. when a brief, open question is asked) compared to when open questions are followed by prompts (e.g. ‘tell me about who as there’, ‘what happened?’, etc.).

Background Previous studies show that activity in the posterior default mode network (pDMN), including the posterior cingulate cortex and the precuneus, is correlated with the success of long-term episodic memory retrieval. However, the role of the anterior DMN (aDMN) including the medial prefrontal cortex is still unclear. Some studies show that activating the medial prefrontal cortex improves memory retrieval while other studies show deactivation of the medial prefrontal cortex in successful retrieval of episodic memories, suggesting a possible functional dissociation between the aDMN and pDMN. Objective In the current study, we aim to causally explore this probable dissociation using high-definition transcranial direct current stimulation (HD-tDCS). Methods We perform a randomised double-blinded two-visit placebo-controlled study with 84 healthy young adults. During Visit 1 they learn 75 Swahili-English word-associations. Seven days later, they randomly receive either anodal, cathodal or sham HD-tDCS targeting the pDMN or aDMN while they recall what they have previously learned. Results We demonstrate that anodal stimulation of the pDMN and cathodal stimulation of the aDMN, equally improve the percentage of Swahili-English word-associations recalled 7 days after learning. Conclusions Modulating the activity in the aDMN and pDMN causally affect memory retrieval performance. HD-tDCS of the aDMN and pDMN shows that anodal stimulation of the pDMN and cathodal stimulation of the aDMN increases memory retrieval performance one week after the learning phase. Given consistent evidence, it is highly likely that we are increasing the activity in the pDMN with anodal pDMN stimulation. However, it is not clear if cathodal HD-tDCS targetting aDMN works via decoupling from the pDMN or via indirectly disinhibit pDMN.

Successful recall of brand names often determines consumer decisions. Yet, unaided recall fails increasingly as adult consumers get older, which is a threat to brand awareness in aging societies. Still, consumer research has not explored if personally relevant episodic memories consumers associate with a brand can support brand-name memory when consumers age. This study, therefore, explores how cognitive aging affects the links between the recall of brand names from semantic memory and the subjective quality of brand-related autobiographical memories (AMs). Experimental data from 20- to 33-year-old and 60- to 90-year-old participants suggest that consumers associate successfully recalled brand names with more significant, phenomenologically richer AMs, and that this connection between semantic and episodic memory is stronger in older adults. We discuss how research and brand communication could utilize AMs to further understand and reduce negative impacts of aging on brand awareness.

Episodic memory enables us to form a bank of autobiographical memories across our lifespan. The relationship between autobiographical memory and laboratory-measures of episodic memory is complicated and these processes might be differentially affected by ageing (e.g. Diamond et al., [2020]. Different patterns of recollection for matched real-world and laboratory-based episodes in younger and older adults. Cognition, 202, 104309.). Here, we examine whether the ability to recall one’s own visual perspective relates to richness of autobiographical recall, and how this relationship is affected by age. Memory of perspective at encoding, was assessed in younger (18–35 years) and older adults (65–85 years). Participants, wearing head cameras, viewed arrays of objects. Later they were asked which images represented earlier scenes, and if the image was taken from their perspective (i.e. from their camera). Performance was compared with autobiographical memory. Accuracy in identifying their own perspective correlated with autobiographical scores. Age-group was a moderating factor in this relationship. Subsequently, new participants encoded photographs of objects and were later asked whether they recognised the images. Visual perspective was manipulated in these photographs. In this task there was no relationship between performance and autobiographical memory. In younger adults only 3-D encoding of scenes relates directly to autobiographical memory but ability to complete these two tasks appears to operate independently in the older group.

Here, we review the literature on autonoetic consciousness in episodic memory, our memory for personally experienced events, in order to understand its relationship to visual perspective. Autonoeti...

Objective:Memory symptoms and objective impairment are common in HIV disease and are associated with disability. A paradoxical issue is that objective episodic memory failures can interfere with accurate recall of memory symptoms. The present study assessed whether responses on a self-report scale of memory symptoms demonstrate measurement invariance in persons with and without objective HIV-associated memory impairment.Method:In total, 505 persons with HIV completed the Prospective and Retrospective Memory Questionnaire (PRMQ). Objective memory impairment (n = 141) was determined using a 1-SD cutoff on clinical tests of episodic memory. PRMQ measurement invariance was assessed by confirmatory factor analyses examining a one-factor model with increasing cross-group equality constraints imposed on factor loadings and item thresholds (i.e., configural, weak, and strong invariance).Results:Configural model fit indicated that identical items measured a one-factor model for both groups. Comparison to the weak model indicated that factor loadings were equivalent across groups. However, there was evidence of partial strong invariance, with two PRMQ item thresholds differing across memory impairment groups. Post hoc analyses using a 1.5-SD memory impairment cutoff (n = 77) revealed both partial weak and partial strong invariance, such that PRMQ item loadings differed across memory groups for three items.Conclusions:The PRMQ demonstrated a robust factor structure among persons with and without objective HIV-associated memory impairment. However, on select PRMQ items, individuals with memory impairment reported observed scores that were relatively higher than their latent score, while items were more strongly associated with the memory factor in a group with greater memory impairment.

Many studies suggest that information about past experience, or episodic memory, is divided into discrete units called “events.” Yet we can often remember experiences that span multiple events. Events that occur in close succession might simply be linked because of their proximity to one another, but we can also build links between events that occur farther apart in time. Intuitively, some kind of organizing principle should enable temporally distant events to become bridged in memory. We tested the hypothesis that episodic memory exhibits a narrative-level organization, enabling temporally distant events to be better remembered if they form a coherent narrative. Furthermore, we tested whether post-encoding memory consolidation is necessary to integrate temporally distant events. In three experiments, participants learned and subsequently recalled events from fictional stories, in which pairs of temporally distant events involving side characters (“sideplots”) either formed one coherent narrative or two unrelated narratives. Across participants, we varied whether recall was assessed immediately after learning, or after a delay: 24 hours, 12 hours between morning and evening (“wake”), or 12 hours between evening and morning (“sleep”). Participants recalled more information about coherent than unrelated narrative events, in most delay conditions, including immediate recall and wake conditions, suggesting that post-encoding consolidation was not necessary to integrate temporally distant events into a larger narrative. Furthermore, post hoc modeling across experiments suggested that narrative coherence facilitated recall over and above any effects of sentence-level semantic similarity. This reliable memory benefit for coherent narrative events supports theoretical accounts which propose that narratives provide a high-level architecture for episodic memory.

Mindfulness attracted increased research interests in the last decade, reporting an overall beneficial effect of this practice on cognitive performances. Nevertheless, recently a possible detrimental impact of mindfulness has been underlined. While the effect of mindfulness on memory remains under-explored, recent studies have observed an increased false-memory susceptibility after mindfulness practice. A possible explanatory mechanism has been suggested, related to the nature of the studied material. For semantically related information, mindfulness would increase false memories; however, the addition of rich perceptual information could prevent this detrimental effect. The present study aimed to verify this hypothesis by testing the impact of state mindfulness induced by a short meditation session, and dispositional mindfulness on the production of false memory for pictorial material presented in a complex virtual environment. We employed a virtual reality version of the Deese–Roediger–McDermott paradigm (DRM), a classical protocol to induce false memories. Contrary to previous studies, we did not observe any effect of mindfulness on false or correct memories (free recall and recognition) after a short mindfulness practice session compared to a control condition. Nonetheless, we found a beneficial effect of mindfulness practice on memory sensitivity. Additionally, we reported a positive and negative effect of dispositional mindfulness on memory outcomes. While the Non-Reactivity facet was associated with overall better memory performances, we observed an association between the Acting with Awareness facet and an increased recollection of lures. We discuss these findings in line with a recent proposal on the link between mindfulness and episodic memory.

We present an algorithmic method for aligning recall fixations with encoding fixations, to be used in looking-at-nothing paradigms that either record recall eye movements during silence or want to speed up data analysis with recordings of recall data during speech. The algorithm utilizes a novel consensus-based elastic matching algorithm to estimate which encoding fixations correspond to later recall fixations. This is not a scanpath comparison method, as fixation sequence order is ignored and only position configurations are used. The algorithm has three internal parameters and is reasonable stable over a wide range of parameter values. We then evaluate the performance of our algorithm by investigating whether the recalled objects identified by the algorithm correspond with independent assessments of what objects in the image are marked as subjectively important. Our results show that the mapped recall fixations align well with important regions of the images. This result is exemplified in four groups of use cases: to investigate the roles of low-level visual features, faces, signs and text, and people of different sizes, in recall of encoded scenes. The plots from these examples corroborate the finding that the algorithm aligns recall fixations with the most likely important regions in the images. Examples also illustrate how the algorithm can differentiate between image objects that have been fixated during silent recall vs those objects that have not been visually attended, even though they were fixated during encoding.

Recent evidence suggests that some simulations of future events are encoded in memory and later recalled as "memories of the future," but the factors that determine the memorability of future simulations remain poorly understood. The current research aimed to test the hypothesis that imagined future events are better memorized when they are integrated in autobiographical knowledge structures. Across two experiments, we found that future events that involved the self were better recalled than future events that involved an acquaintance (Experiment 1), and that future events that were related to personal goals were better recalled than future events that were unrelated to goals (Experiment 2). Although self-reference and personal goals influenced the phenomenological characteristics of future simulations (e.g., their vividness and the clarity of event components), the enhanced recall of self-relevant and goal-relevant simulations was not simply due to these differences in the characteristics of simulations. Taken together, these findings suggest that the integration of simulated events with preexisting autobiographical knowledge is an important determinant of memories of the future.

Time is usually conceived of in terms of space: many natural languages refer to time according to a back-to-front axis. Indeed, whereas the past is usually conceived to be “behind us”, the future is considered to be “in front of us.” Despite temporal coding is pivotal for the development of autonoetic consciousness, little is known about the organization of autobiographical memories along this axis. Here we developed a spatial compatibility task (SCT) to test the organization of autobiographical memories along the sagittal plane, using spatiotemporal interference. Twenty-one participants were asked to recall both episodic and semantic autobiographical memories (EAM and SAM, respectively) to be used in the SCT. Then, during the SCT, they were asked to decide whether each event occurred before or after the event presented right before, using a response code that could be compatible with the back-to-front axis (future in front) or not (future at back). We found that performance was significantly worse during the non-compatible condition, especially for EAM. The results are discussed in light of the evidence for spatiotemporal encoding of episodic autobiographical memories, taking into account possible mechanisms explaining compatibility effects. Supplementary Information The online version contains supplementary material available at 10.3758/s13423-021-01906-z.

Similarity between memories is a primary cause of interference and forgetting. Exaggerating subtle differences between memories is therefore a potential mechanism for reducing interference. Here, we report a human fMRI study (n= 29, 19 female) that tested whether behavioral and neural expressions of memories are adaptively distorted to reduce interference. Participants learned and repeatedly retrieved object images, some of which were identical except for subtle color differences. Behavioral measures of color memory revealed exaggeration of differences between similar objects. Importantly, greater memory exaggeration was associated with lower memory interference. fMRI pattern analyses revealed that color information in parietal cortex was stronger during memory recall when color information was critical for discriminating competing memories. Moreover, greater representational distance between competing memories in parietal cortex predicted greater color memory exaggeration and lower memory interference. Together, these findings reveal that competition between memories induces adaptive, feature-specific distortions in parietal representations and corresponding behavioral expressions.SIGNIFICANCE STATEMENTSimilarity between memories is a primary cause of interference and forgetting. Here, we show that, when remembering highly similar objects, subtle differences in the features of these objects are exaggerated in memory to reduce interference. These memory distortions are reflected in, and predicted by, overlap of activity patterns in lateral parietal cortex. These findings provide unique insight into how memory interference is resolved and specifically implicate lateral parietal cortex in representing feature-specific memory distortions.

The entorhinal cortex is subdivided into anterolateral entorhinal cortex (alERC) and posteromedial entorhinal cortex (pmERC) subregions, which are theorized to support distinct cognitive roles. This distinction is particularly important as the alERC is one of the earliest cortical regions affected by Alzheimer's pathology and related neurodegeneration. The relative associations of alERC/pmERC with neuropsychological test performance have not been examined. We examined how alERC/pmERC volumes differentially relate to performance on 1) the Modified Rey Auditory Learning Test (ModRey), a verbal memory test designed to assess normal/preclinical populations, 2) the Montreal Cognitive Assessment (MoCA), and 3) the National Alzheimer's Coordinating Center neuropsychological battery. We also examined whether alERC/pmERC volumes correlate with Alzheimer's disease cerebrospinal fluid (CSF) biomarkers. In 65 cognitively healthy (CDR = 0) older adults, alERC, but not pmERC, volume was associated with ModRey memory retention. Only alERC volume differentiated between participants who scored above and below the MoCA cutoff score for impairment. Evaluating the MoCA subdomains revealed that alERC was particularly associated with verbal recall. On the National Alzheimer's Coordinating Center battery, both alERC and pmERC volumes were associated with Craft story recall and Benson figure copy, but only alERC volume was associated with Craft story retention and semantic fluency. Neither alERC nor pmERC volume correlated with CSF levels of amyloid or tau, and regression analyses showed that alERC volume and CSF amyloid levels were independently associated with ModRey retention performance. Taken together, these results suggest that the alERC is important for memory performance and that alERC volume differences are related to a pattern of neuropsychological test performance (i.e., impairments in episodic memory and semantic fluency) typically seen in clinical Alzheimer's disease.

Memory and metamemory processes are essential to retrieve detailed memories and appreciate the phenomenological experience of recollection. Developmental cognitive neuroscience has made strides in revealing the neural changes associated with improvements in memory and metamemory during childhood and adolescence. We argue that hippocampal changes, in concert with surrounding cortical regions, support developmental improvements in the precision, complexity, and flexibility of memory representations. In contrast, changes in frontoparietal regions promote efficient encoding and retrieval strategies. A smaller body of literature on the neural substrates of metamemory development suggests that error monitoring processes implemented in the anterior insula and dorsal anterior cingulate cortex trigger, and perhaps support the development of, metacognitive evaluationsin the prefrontal cortex, while developmental changes in the parietal cortex support changes in the phenomenological experience of episodic retrieval. Our conclusions highlight the necessity of integrating these lines of research into a comprehensive model on the neurocognitive development of episodic recollection.

1.AbstractModels of memory formation posit that recollection as compared to familiarity-based memory depends critically on the hippocampus, which binds features of an event to its context. For this reason, the contrast between study items that are later recollected versus those that are recognized on the basis of familiarity should reveal electrophysiological patterns in the hippocampus selectively involved in associative memory encoding. Extensive data from studies in rodents support a model in which theta oscillations fulfill this role, but results in humans results have not been as clear. Here, we employed an associative recognition memory procedure to identify hippocampal correlates of successful associative memory encoding and retrieval in patients undergoing intracranial EEG monitoring. We identified a dissociation between 2– 5 Hz and 5–9 Hz theta oscillations, by which 2–5 Hz oscillations uniquely were linked with successful associative memory in both the anterior and posterior hippocampus. These oscillations exhibited a significant phase reset that also predicted successful associative encoding, distinguished recollected from familiar items at retrieval, and contributed to reinstatement of encoding-related patterns that distinguished these items. Our results provide direct electrophysiological evidence that 2–5 Hz hippocampal theta oscillations support the encoding and retrieval of memories based on recollection but not familiarity.2.Significance StatementExtensive fMRI evidence suggests that the hippocampus plays a selective role in recollection rather than familiarity, during both encoding and retrieval. However, there is little or no electrophysiological evidence that speaks to whether the hippocampus is selectively involved in recollection. Here, we used intracranial EEG from human participants engaged in an associative recognition paradigm. The findings suggest that oscillatory power and phase reset in the hippocampus are selectively associated with recollection rather than familiarity-based memory judgements. Furthermore, reinstatement of oscillatory patterns in the hippocampus was stronger for successful recollection than familiarity. Collectively, the findings support a role for hippocampal theta oscillations in human episodic memory.

AMD has been linked to memory deficits, with no established neural mechanisms. In order to describe how resting-state, brain network functional connectivity relates to memory and AMD status in older adults without dementia, we collected resting-state brain fMRI and standardized verbal recall tests from 42 older adults with AMD and 41 age-matched controls. We used seed-based whole brain analysis to quantify the strength of functional connectivity between hubs of the default mode network (DMN) and a network of medial temporal regions relevant for memory. Our results indicated neither memory performance nor network connectivity differed by AMD status. However, the AMD participants exhibited stronger relationships than the controls between memory performance and connectivity from the memory network hub (left parahippocampal) to two other regions: the left temporal pole and the right superior/middle frontal gyri. Also, the connectivity between the medial prefrontal cortex and posterior cingulate cortex of DMN correlated more strongly with memory performance in AMD compared to control. We concluded that stronger brain-behavior correlation in AMD may suggest a role for region-specific connectivity in supporting memory in the context of AMD.

Older adults experience deficits in associative memory. However, age-related differences are reduced when information is consistent with prior knowledge (i.e., schematic support), suggesting that episodic and semantic memory are interrelated. It is unclear what role metacognitive processes play in schematic support. Prior knowledge may reduce encoding demands, but older adults may allocate cognitive resources to schema-consistent information because it is more meaningful. We examined metacognitive awareness of and control over associative information that was consistent or inconsistent with prior knowledge. In Experiment 1, participants self-paced their study of grocery items paired with either market prices or unusually high prices and were tested on the exact price of each item over four study-test lists with new items on each list. In Experiment 2, participants studied items for a fixed time but made judgments of learning (JOLs) at encoding. Older adults better remembered the prices of market-value items than overpriced items. In Experiment 1, younger and older adults studied overpriced items longer than market-priced items, consistent with a discrepancy reduction model of self-regulated learning, but study time did not relate to later recall accuracy, suggesting a labor-in-vain effect. In Experiment 2, participants gave higher JOLs to market-priced items than overpriced items and were generally metacognitively aware of the benefits of schematic support. Together, these results suggest that the benefits of schematic support may not be dependent on or influenced by metacognitive control processes, supporting the hypothesis that episodic memory may be less distinct from semantic memory in younger and older adults.

The qualities of remembered experiences are often used to inform “reality monitoring” judgments, our ability to distinguish real and imagined events. Previous experiments have tended to investigate only whether reality monitoring decisions are accurate or not, providing little insight into the extent to which reality monitoring may be affected by qualities of the underlying mnemonic representations. We used a continuous-response memory precision task to measure the quality of remembered experiences that underlie two different types of reality monitoring decisions: self/experimenter decisions that distinguish actions performed by participants and the experimenter and imagined/perceived decisions that distinguish imagined and perceived experiences. The data revealed memory precision to be associated with higher accuracy in both self/experimenter and imagined/perceived reality monitoring decisions, with lower precision linked with a tendency to misattribute self-generated experiences to external sources. We then sought to investigate the possible neurocognitive basis of these observed associations by applying brain stimulation to a region that has been implicated in precise recollection of personal events, the left angular gyrus. Stimulation of angular gyrus selectively reduced the association between memory precision and self-referential reality monitoring decisions, relative to control site stimulation. The angular gyrus may, therefore, be important for the mnemonic processes involved in representing remembered experiences that give rise to a sense of self-agency, a key component of “autonoetic consciousness” that characterizes episodic memory.

Objective: We evaluated whether memory recall following an extended (1 week) delay predicts cognitive and brain structural trajectories in older adultsMethod:Clinically normal older adults (52–92 years old) were followed longitudinally for up to 8 years after completing a memory paradigm at baseline [Story Recall Test (SRT)] that assessed delayed recall at 30 min and 1 week. Subsets of the cohort underwent neuroimaging (N = 134, mean age = 75) and neuropsychological testing (N = 178–207, mean ages = 74–76) at annual study visits occurring approximately 15–18 months apart. Mixed-effects regression models evaluated if baseline SRT performance predicted longitudinal changes in gray matter volumes and cognitive composite scores, controlling for demographics.Results:Worse SRT 1-week recall was associated with more precipitous rates of longitudinal decline in medial temporal lobe volumes (p = .037), episodic memory (p = .003), and executive functioning (p = .011), but not occipital lobe or total gray matter volumes (demonstrating neuroanatomical specificity; p > .58). By contrast, SRT 30-min recall was only associated with longitudinal decline in executive functioning (p = .044).Conclusions:Memory paradigms that capture longer-term recall may be particularly sensitive to age-related medial temporal lobe changes and neurodegenerative disease trajectories. (JINS, 2020, xx, xx-xx)

Human T cell leukemia virus type-I (HTLV-1) infection courses with a myelopathy, the tropical spastic paraparesis (HAM/TSP). In a case-control study, we compared the neuropsychological profile and functional characteristics in two case HTLV-1-infected groups (asymptomatic and with HAM/TSP) with a control group negative for HTLV-1. Subjects were paired for age, sex, and educational features. The case group differed from control group in neuropsychological measures such as in episodic memory recall, executive functions, and fine motor dexterity measure. Individuals with HAM/TSP have more depressive symptoms and worst performance in activities of daily living (ADL) presenting a less functionality. In multivariate models, the fine motor performance, the executive functioning, the recognition memory, and the depressive symptoms explained part of the variance in functionality. Those findings may contribute to understand of everyday life impairments and limitations of HTLV-1-infected population and to organize the rehabilitation. Once more, based in neuropsychological and functional data, we can reaffirm that HTLV-1 is never a benign condition, but sometimes it is only in a stage coursing with less symptoms.

Behavioral data on episodic recollection in autism spectrum disorders (ASD) point limited relational memory functioning. However, the involvement of successive memory processes in the profile of episodic memory in ASD needs more study. Here, we used event-related potentials (ERP) to investigate the time course of episodic recollection with an associative recognition paradigm with picture pairs. Twenty-two participants with ASD and 32 with typical development (TD), all right-handed, were included. Behavioral results confirmed difficulties in correctly recognizing identical pairs in the ASD relative to TD group. We found an unexpected amplitude decrement on the P2 (220-270 msec) and FN400 (350-470 msec) potentials, suggesting diminished priming and familiarity effects in the ASD relative to TD group. However, ERP data revealed that the recognition of associative information relies on the same electrophysiological process (old/new effect in the 600-700-msec late positive component) in ASD participants as in TD ones, with a parietal extension in the ASD group. These results suggest that the electrophysiological processes of associative recognition are qualitatively similar in individuals with and without ASD but may differ quantitatively. This difference may be driven by the reduced early processing of picture pairs that may in turn lead to their diminished integration into the semantic memory system, being partially compensated by a greater involvement of associative memory during the recollection process. Other studies would be useful to go further in identifying these cognitive processes involved in atypical recognition in ASD and their neural substrates. Autism Res 2020, 13: 1998-2016. © 2020 International Society for Autism Research and Wiley Periodicals LLC LAY SUMMARY: We identified diminished performance on the associative recognition of picture pairs in adolescents and young adults with autism when compared to typical development. Electrophysiological data revealed qualitative similarities but quantitative differences between-group, with diminished priming and familiarity processes partially compensated by an enhanced parietal recollection process.

Background Here, we address a pivotal factor in Alzheimer’s prevention—identifying those at risk early, when dementia can still be avoided. Recent research highlights an accelerated forgetting phenotype as a risk factor for Alzheimer’s disease. We hypothesized that delayed recall over 4 weeks would predict cognitive decline over 1 year better than 30-min delayed recall, the current gold standard for detecting episodic memory problems which could be an early clinical manifestation of incipient Alzheimer’s disease. We also expected hippocampal subfield volumes to improve predictive accuracy. Methods Forty-six cognitively healthy older people (mean age 70.7 ± 7.97, 21/46 female), recruited from databases such as Join Dementia Research, or a local database of volunteers, performed 3 memory tasks on which delayed recall was tested after 30 min and 4 weeks, as well as Addenbrooke’s Cognitive Examination III (ACE-III) and CANTAB Paired Associates Learning. Medial temporal lobe subregion volumes were automatically measured using high-resolution 3T MRI. The ACE-III was repeated after 12 months to assess the change in cognitive ability. We used univariate linear regressions and ROC curves to assess the ability of tests of delayed recall to predict cognitive decline on ACE-III over the 12 months. Results Fifteen of the 46 participants declined over the year (≥ 3 points lost on ACE-III). Four-week verbal memory predicted cognitive decline in healthy older people better than clinical gold standard memory tests and hippocampal MRI. The best single-test predictor of cognitive decline was the 4-week delayed recall on the world list (R2 = .123, p = .018, β = .418). Combined with hippocampal subfield volumetry, 4-week verbal recall identifies those at risk of cognitive decline with 93% sensitivity and 86% specificity (AUC = .918, p Conclusions We show that a test of accelerated long-term forgetting over 4 weeks can predict cognitive decline in healthy older people where traditional tests of delayed recall cannot. Accelerated long-term forgetting is a sensitive, easy-to-test predictor of cognitive decline in healthy older people. Used alone or with hippocampal MRI, accelerated forgetting probes functionally relevant Alzheimer’s-related change. Accelerated forgetting will identify early-stage impairment, helping to target more invasive and expensive molecular biomarker testing.