More than language is needed to represent and combine different core knowledge components.

We question Spelke's key claim that the medium, in which contents from different core knowledge systems can be represented and combined, is language-based. Recalling an episodic memory, playing chess, and conducting mental rotation are tasks where core knowledge information is represented and combined. Although these tasks can be described by means of language, these tasks are not inherently language-based. Hence, language may be an important subset of an abstraction medium - not the medium as such.

Recalled through this day but forgotten next week?-retrieval activity predicts durability of partly consolidated memories.

Even partly consolidated memories can be forgotten given sufficient time, but the brain activity associated with durability of episodic memory at different time scales remains unclear. Here, we aimed to identify brain activity associated with retrieval of partly consolidated episodic memories that continued to be remembered in the future. Forty-nine younger (20 to 38 years; 25 females) and 43 older adults (60 to 80 years, 25 females) were scanned with functional magnetic resonance imaging during associative memory retrieval 12 h post-encoding. Twelve hours is sufficient to allow short-term synaptic consolidation as well as early post-encoding replay to initiate memory consolidation. Successful memory trials were classified into durable and transient source memories based on responses from a memory test ~6 d post-encoding. Results demonstrated that successful retrieval of future durable vs. transient memories was supported by increased activity in a medial prefrontal and ventral parietal area. Individual differences in activation as well as the subjective vividness of memories during encoding were positively related to individual differences in memory performance after 6 d. The results point to a unique and novel aspect of brain activity supporting long-term memory, in that activity during retrieval of memories even after 12 h of consolidation contains information about potential for long-term durability.

Differential recall bias in estimating treatment effects in observational studies.

Observational studies are frequently used to estimate the effect of an exposure or treatment on an outcome. To obtain an unbiased estimate of the treatment effect, it is crucial to measure the exposure accurately. A common type of exposure misclassification is recall bias, which occurs in retrospective cohort studies when study subjects may inaccurately recall their past exposure. Particularly challenging is differential recall bias in the context of self-reported binary exposures, where the bias may be directional rather than random and its extent varies according to the outcomes experienced. This paper makes several contributions: (1) it establishes bounds for the average treatment effect even when a validation study is not available; (2) it proposes multiple estimation methods across various strategies predicated on different assumptions; and (3) it suggests a sensitivity analysis technique to assess the robustness of the causal conclusion, incorporating insights from prior research. The effectiveness of these methods is demonstrated through simulation studies that explore various model misspecification scenarios. These approaches are then applied to investigate the effect of childhood physical abuse on mental health in adulthood.

Temporal Recall Strategies in Rheumatoid Arthritis Patients' Emotionally Intense Life Events.

BACKGROUND: Rheumatoid arthritis (RA) patients often encounter psychological challenges due to chronic pain, fatigue, side effects of medications, and disability. This study examines the relationship between autobiographical narratives and recollection patterns in RA patients. We investigated how different recall strategies for positive life events affect the emotional processing of negative episodes. We hypothesized that vividly recalling positive life events provides psychological resources that support a more intense emotional elaboration of stressful memories, allowing individuals to delve deeper into negative life experiences. Additionally, we explored the impact of these perspectives on self-reported well-being and physical health, proposing that re-living positive events improves overall well-being. METHODS: We collected and analyzed high-point and low-point life-story episodes from 60 RA patients (85% female; age mean 61 ± 11 years; range 37-79) using episodic narrative interviews and the Narrative Categorical Content Analysis algorithm (NarrCat). Participants were categorized into 2 clusters based on their temporal perspective during high-point episodes: 25 used a Retrospective viewpoint, while 35 employed a Re-experiencing strategy. Depression and anxiety were assessed with the Hospital Anxiety and Depression Scale (HADS), and functioning was measured using the Health Assessment Questionnaire (HAQ). RESULTS: The Re-experiencing group, which was more likely to articulate their high-point episode in vivid and real-time narrative, used more psychological perspectives (U(58) = 223, p < 0.01) and showed heightened emotional frequency (U(58) = 280, p < 0.05; positive: U(58) = 328, p < 0.05; negative: U(58) = 278, p < 0.05) in low-point episodes. No significant difference emerged between the two groups regarding psychological state (anxiety, depressive symptoms) and physical impairment. CONCLUSIONS: Vividly recalling positive events may facilitate a deeper exploration of negative memories. The Re-experiencing group showed increased positive emotions during low points, suggesting better emotion regulation. However, no significant association was found between recalling strategies, psychological state, and physical impairment. This indicates that further research is needed to determine whether re-experiencing positive life events is adaptive or maladaptive.

Event representation at the scale of ordinary experience.

Weeks are divided into weekdays and weekends; years into semesters and seasons; lives into stages like childhood, adulthood, and adolescence. How does the structure of experience shape memory? Though much work has examined event representation in human cognition, little work has explored event representation at the scale of ordinary experience. Here, we use shared experiences - in the form of popular television shows - to explore how memories are shaped by event structure at a large scale. We find that memories for events in these shows exhibit several hallmarks of event cognition. Namely, we find that memories are organized with respect to their event structure (boundaries), and that beginnings and endings are better remembered at multiple levels of the event hierarchy simultaneously. These patterns seem to be partially, but not fully, explained by the perceived story-relevance of events. Lastly, using a longitudinal design, we also show how event representations evolve over periods of several months. These results offer an understanding of event cognition at the scale of ordinary human lives.

Comparing behaviours induced by natural memory retrieval and optogenetic reactivation of an engram ensemble in mice.

Memories are thought to be stored within sparse collections of neurons known as engram ensembles. Neurons active during a training episode are allocated to an engram ensemble ('engram neurons'). Memory retrieval is initiated by external sensory or internal cues present at the time of training reactivating engram neurons. Interestingly, optogenetic reactivation of engram ensemble neurons alone in the absence of external sensory cues is sufficient to induce behaviour consistent with memory retrieval in mice. However, there may exist differences between the behaviours induced by natural retrieval cues or artificial engram reactivation. Here, we compared two defensive behaviours (freezing and the syllable structure of ultrasonic vocalizations, USVs) induced by sensory cues present at training (natural memory retrieval) and optogenetic engram ensemble reactivation (artificial memory retrieval) in a threat conditioning paradigm in the same mice. During natural memory recall, we observed a strong positive correlation between freezing levels and distinct USV syllable features (characterized by an unsupervised algorithm, MUPET (Mouse Ultrasonic Profile ExTraction)). Moreover, we observed strikingly similar behavioural profiles in terms of freezing and USV characteristics between natural memory recall and artificial memory recall in the absence of sensory retrieval cues. Although our analysis focused on two behavioural measures of threat memory (freezing and USV characteristics), these results underscore the similarities between threat memory recall triggered naturally and through optogenetic reactivation of engram ensembles. This article is part of a discussion meeting issue 'Long-term potentiation: 50 years on'.

Physical activity and verbal memory performance: Mediating effects of resting-state brain activity.

Verbal short-term and long-term memory are crucial neuropsychological functions involved in core cognitive abilities. They constitute vital components of subjective well-being and academic achievement. To date, there is limited research on the association between regular physical activity and memory abilities during young adulthood. The Individual Alpha Peak Frequency (IAPF) contributes to various cognitive abilities and also appears to be sensitive to physical activity. Consequently, the IAPF has the potential to underlie the association between physical activity and verbal memory. We examined the direct relation of physical activity and verbal memory, and the potential indirect relation via IAPF in young adults. Regular physical activity was assessed via accelerometry on seven consecutive days in 115 participants (N=115, 48% female) aged 18-35 years (M=24.1, SD=3.8). In addition, verbal memory performance was assessed using an immediate and delayed free-recall task. Brain activity during rest was recorded with EEG, and IAPF was extracted for mediation analyses. Path analysis revealed pronounced sex differences in the association between physical activity, IAPF, and verbal memory performance. Exclusively in female participants, higher vigorous physical activity levels were associated with better recall performance. In contrast, no association of physical activity and memory was found in male participants. However, being more physically active was related to a higher IAPF exclusively in male participants. Physical activity shows differential associations between IAPF and verbal memory in male and female participants. However, the lack of a mediating role of IAPF suggests that this neurophysiological marker cannot explain these specific associations in young adults.

Validity and Reproducibility of an Electronic Food Frequency Questionnaire in Argentinian Adults.

This study aimed to validate a semiquantitative electronic food frequency questionnaire (eFFQ) in estimating the intake of a comprehensive list of nutrients and bioactive compounds among adults from six regions of Argentina using multiple 24 h dietary recall (24HR) as a reference. A total of 163 adults completed two administrations of the eFFQ and four 24HRs. The paired t-test/Wilcoxon signed-rank test, Spearman/Pearson correlations, cross-classification, weighted kappa statistics, and Bland-Altman plots were employed to determine relative validity. To determine reproducibility, intraclass correlations (ICC), cross-classification, and weighted kappa statistics were calculated. For relative validity, crude correlations ranged from 0.15 to 0.57; energy adjustment and de-attenuation slightly improved most of these correlations. In cross-classification analysis, agreements within one quintile adjacent to exact agreement (EA ± 1) ranged from 52.2% to ~74%; extreme misclassifications were < 7%. For reproducibility, the crude ICC ranged from 0.29 to 0.85, showing moderate to good correlations for most nutrients. Cross-classification analysis showed agreement levels for the EA ± 1 quintile of 70.6% to 87.7%. Weighted kappa values ranged from 0.21 to 0.62. The results show that this eFFQ is relatively valid in ranking adults according to their nutrient intake and has an acceptable reproducibility, yet it slightly overestimates the intake of most nutrients.

Assessing the relative validity of a web-based self-administered 24-hour dietary recall in a Canadian adolescent's population.

BACKGROUND: Healthy eating habits at a young age are crucial to support growth and development and good general health. In this context, monitoring youth dietary intakes adequately with valid tools is important to develop efficient interventions and identify groups that are more at risk of inadequate intakes. This study aimed to assess the relative validity of the self-administered web-based 24-h dietary recall (R24W) for evaluating energy and nutrient intakes among active adolescents. METHODS: Participants were invited to complete one interviewer-administered 24-h dietary dietary recall and the R24W on up to three occasions within one month. A total of 272 French-speaking active adolescents aged 12 to 17 years from the province of Québec were invited to complete three R24W and one interview-administered 24-h recall. Student's t-test and correlations were conducted on sex-adjusted data. Percent differences, cross-classification (percentage of agreement), weighted Kappa and Bland-Altman plots were calculated. RESULTS: Mean (SD) energy intake from the R24W was 8.8% higher than from the interview-administered 24-h dietary recall (2558 kcal ± 1128 vs. 2444 kcal ± 998, p < 0.05). Significant differences in mean nutrient intake between the R24W and the interview-administered 24-h dietary recall ranged from 6.5% for % E from fat (p < 0.05) to 25.2% for saturated fat (p < 0.001), i.e., higher values with R24W. Sex-adjusted correlations were significant for all nutrients except for % E from proteins and thiamin (range: 0.24 to 0.52, p < 0.01). Cross-classification demonstrated that 36.6% of the participants were classified in the same fourth with both methods, 39.6% in the adjacent fourth, and 5.7% misclassified. Bland-Atman plots revealed proportional bias between the two methods for 7/25 nutrients. Completing at least two recalls with the R24W increased the precision of intake estimates. CONCLUSION: These data suggest that the R24W presents an acceptable relative validity compared to a standard interview-administered 24-h recall for estimating energy and most nutrients in a cohort of French-speaking adolescents from the province of Québec.

Divergent roles of early visual cortex and inferior frontal junction in visual working memory.

BACKGROUND: Recent studies indicate that both prefrontal and visual regions play critical roles in visual working memory (VWM), with prefrontal regions mainly associated with executive functions, and visual cortices linked to representations of memory contents. VWM involves the selective filtering of irrelevant information, yet the specific contributions of the prefrontal regions and visual cortex in this process remain unclear. OBJECTIVE: To understand the dynamic causal roles of prefrontal and visual regions in VWM. METHODS: The differentiation of VWM components was achieved using a computational model that incorporated a swap rate for non-target stimuli. Single-pulse magnetic transcranial stimulation (spTMS) was delivered to the early visual cortex (EVC) and the inferior frontal junction (IFJ) across different phases of an orientation recall task that with or without distractors. RESULTS: Our results indicate that spTMS over the EVC and IFJ influences VWM particularly when distractors are present. VWM precision can be impacted by spTMS applied to either region during the early retention, while spTMS effect is especially prominent when EVC is stimulated during the late retention phase and when directed at the ipsilateral EVC. Conversely, the probability of accurately recalling the target exhibited comparable patterns when spTMS was administered to either the EVC or IFJ. CONCLUSIONS: We highlight the "sensory recruitment" of VWM characterized by critical involvement of EVC particularly in the information-filtering process within VWM. The maintenance of memory content representations necessitates ongoing communication between the EVC and IFJ throughout the entirety of the VWM process in a dynamic pattern.

Tummy Time Tracking: Examining Agreement Between Parent Recall and Direct Observation in Infants.

IMPORTANCE: Parent recall is the primary method for measuring positioning practices such as tummy time in infants. Concerns regarding the accuracy of parent recall have been raised in the literature. To date, no study has examined the agreement of tummy time recall measures with gold-standard methods. OBJECTIVE: To assess the agreement between parental recall versus direct observation of tummy time in infants, and to explore the impact of prematurity on this relationship. DESIGN: Cross-sectional observational study, spanning 1 yr. SETTING: Participants' homes Participants: Thirty-two infant-parent dyads (19 full-term, 13 preterm), with infants ages 3 to 6 mo and caregivers ages older than 18 yr. OUTCOME AND MEASURES: Home-recorded videos of infant play across 3 days were used as a proxy for direct observation of tummy time and compared with a 12-item parent recall survey. RESULTS: Parent recall had a significant moderate correlation (ρ = .54, p = .002) with direct observation in full-term infants but was not correlated (p = .23) with direct observation in preterm infants. On average, parents of preterm infants overestimated tummy time by 2.5 times per day compared with direct observation. CONCLUSIONS AND RELEVANCE: For full-term infants, parent recall measures of tummy time exhibit an acceptable level of agreement with direct observation and can be reliably used over shorter periods. Parents of preterm infants may display a bias in recalling tummy time, leading to overestimations. To accurately assess tummy time in this population, a combination of subjective and objective measures should be explored. Plain-Language Summary: Tummy time is an essential movement experience for infants, especially for preterm infants, who are at a higher risk for motor delays. The most common way to track tummy time is through parent reports, or recall, versus a practitioner directly observing tummy time in the home. Despite the widespread use of parent recall to track tummy time, no study has examined the accuracy of parent recall versus direct observation in the home. Accurately assessing tummy time is crucial for improving and supporting health outcomes for infants. This study found that prematurity may affect the accuracy of parent recall for assessing tummy time in young infants. The authors discuss the implications of this finding and provide suggestions to guide the selection of appropriate methods to measure tummy time in clinical practice and research studies.

Replay of incidentally encoded novel odors in the rat.

Although events are not always known to be important when they occur, people can remember details about such incidentally encoded information using episodic memory. Sheridan et al. (2024) argued that rats replayed episodic memories of incidentally encoded information in an unexpected assessment of memory. In one task, rats reported the third-last item in an explicitly encoded list of trial-unique odors. In a second task, rats foraged in a radial maze in the absence of odors. On a critical test, rats foraged in the maze, but scented lids covered the food. Next, memory of the third-last odor was assessed. The rats correctly answered the unexpected question. Because the odors used in the critical test were the same as those used during training, automatically encoding odors for the purpose of taking an upcoming test of memory (stimulus generalization) may have been encouraged. Here, we provided an opportunity for incidental encoding of novel odors. Previously trained rats foraged in the radial maze with entirely novel odors covering the food. Next, memory of the third-last odor was assessed. The rats correctly answered the unexpected question. High accuracy when confronted with novel odors provides evidence that the rats did not automatically encode odors for the purpose of taking an upcoming test, ruling out stimulus generalization. We conclude that rats encode multiple pieces of putatively unimportant information, and later replayed a stream of novel episodic memories when that information was needed to solve an unexpected problem.

Tongue coating-dependent superior temporal sulcus remodeling in amnestic mild cognitive impairment.

Tongue coating affects cognition, and cognitive decline at early stage also showed relations to functional and structural remodeling of superior temporal sulcus (STS) in amnestic mild cognitive impairment (aMCI). The potential correlation between disparate cognitive manifestations in aMCI patients with different tongue coatings, and corresponding mechanisms of STS remodeling remains uncharted. In this case-control study, aMCI patients were divided into thin coating (n = 18) and thick coating (n = 21) groups. All participants underwent neuropsychological evaluations and multimodal magnetic resonance imaging. Group comparisons were conducted in clinical assessments and neuroimaging measures of banks of the STS (bankssts). Generalized linear models were constructed to explore relationships between neuroimaging measures and cognition. aMCI patients in the thick coating group exhibited significantly poorer immediate and delayed recall and slower information processing speed (IPS) (P < 0.05), and decreased functional connectivity (FC) of bilateral bankssts with frontoparietal cortices (P < 0.05, AlphaSim corrected) compared to the thin coating group. It was found notable correlations between cognition encompassing recall and IPS, and FC of bilateral bankssts with frontoparietal cortices (P < 0.05, Bonferroni's correction), as well as interaction effects of group × regional homogeneity (ReHo) of right bankssts on the first immediate recall (P < 0.05, Bonferroni's correction). aMCI patients with thick coating exhibited poor cognitive performance, which might be attributed to decreased FC seeding from bankssts. Our findings strengthen the understanding of brain reorganization of STS via which tongue coating status impacts cognition in patients with aMCI.

Observing the suppression of individual aversive memories from conscious awareness.

When reminded of an unpleasant experience, people often try to exclude the unwanted memory from awareness, a process known as retrieval suppression. Here we used multivariate decoding (MVPA) and representational similarity analyses on EEG data to track how suppression unfolds in time and to reveal its impact on item-specific cortical patterns. We presented reminders to aversive scenes and asked people to either suppress or to retrieve the scene. During suppression, mid-frontal theta power within the first 500 ms distinguished suppression from passive viewing of the reminder, indicating that suppression rapidly recruited control. During retrieval, we could discern EEG cortical patterns relating to individual memories-initially, based on theta-driven visual perception of the reminders (0 to 500 ms) and later, based on alpha-driven reinstatement of the aversive scene (500 to 3000 ms). Critically, suppressing retrieval weakened (during 360 to 600 ms) and eventually abolished item-specific cortical patterns, a robust effect that persisted until the reminder disappeared (780 to 3000 ms). Representational similarity analyses provided converging evidence that retrieval suppression weakened the representation of target scenes during the 500 to 3000 ms reinstatement window. Together, rapid top-down control during retrieval suppression abolished cortical patterns of individual memories, and precipitated later forgetting. These findings reveal a precise chronometry on the voluntary suppression of individual memories.

Falas maternas sobre alimentação infantil / Maternal discourses on child feeding / Recuerdos maternos de la alimentación de sus hijos

Introdução: A alimentação aparece em todas as explicações sobre os processos e ações humanas, o que confirma o fato de não ser uma conduta natural, mas efeito da interação entre indivíduos, inaugurada na relação mãe-bebê. Objetivo: Identificar apagamentos, lapsos e resistência nas memórias de mães de crianças, adolescentes e jovens adultos primogênitos, sobre o processo de alimentação de seus filhos. Método: descritivo, exploratório realizado com mães de crianças, adolescentes e adultos com desenvolvimento típico que responderam a um questionário sobre a alimentação. Resultados: As perguntas relativas à amamentação e ao desmame foram respondidas de forma assertiva, mostrando que estes são fatos simbólicos, que marcam a lembrança materna. Conclusão: As lembranças maternas sobre as cenas alimentares com seus filhos mostram os movimentos de união e separação entre o par interacional. É possível apontar que apenas para as perguntas relativas à amamentação e ao desmame as respostas são totalmente assertivas, indiciando que são fatos simbólicos que marcam a memória materna. (AU)

Introduction: Feeding appears in all explanations about human processes and actions, which confirms the fact that it is not a natural behavior, but an effect of the interaction between individuals, initiated in the mother-baby relationship. Objective: To identify erasures, lapses and resistance in the memories of mothers of first-born children, adolescents and young adults, about the process of feeding their children. Method: descriptive, exploratory carried out with mothers of children, adolescents and adults with typical development who responded to a questionnaire about nutrition. Results: Questions regarding breastfeeding and weaning were answered assertively, showing that these are symbolic facts, which mark maternal memories. Conclusion: Maternal memories of eating scenes with their children show the movements of union and separation between the interactional pair. It is possible to point out that only for the questions related to breastfeeding and weaning the answers are completely assertive, indicating that they are symbolic facts that mark maternal memory. (AU)

Introducción: La alimentación aparece en todas las explicaciones sobre los procesos y acciones humanas, lo que confirma que no es un comportamiento natural, sino un efecto de la interacción entre individuos, iniciada en la relación madre-bebé. Objetivo: Identificar borramientos, lapsos y resistencias en los recuerdos de madres de primogénitos, adolescentes y adultos jóvenes, sobre el proceso de alimentación de sus hijos. Método: descriptivo, exploratorio realizado con madres de niños, adolescentes y adultos con desarrollo típico que respondieron un cuestionario sobre nutrición. Resultados: Las preguntas sobre lactancia materna y destete fueron respondidas de manera asertiva, demostrando que se trata de hechos simbólicos, que marcan los recuerdos maternos. Conclusión: Los recuerdos maternos de escenas de comida con sus hijos muestran los movimientos de unión y separación entre la pareja interaccional. Es posible señalar que sólo para las preguntas relacionadas con la lactancia materna y el destete las respuestas son completamente asertivas, indicando que son hechos simbólicos que marcan la memoria materna. (AU)

Chemogenetic activation of histamine neurons promotes retrieval of apparently lost memories.

Memory retrieval can become difficult over time, but it is important to note that memories that appear to be forgotten might still be stored in the brain, as shown by their occasional spontaneous retrieval. Histamine in the central nervous system is a promising target for facilitating the recovery of memory retrieval. Our previous study demonstrated that histamine H3 receptor (H3R) inverse agonists/antagonists, activating histamine synthesis and release, enhance activity in the perirhinal cortex and help in retrieving forgotten long-term object recognition memories. However, it is unclear whether enhancing histaminergic activity alone is enough for the recovery of memory retrieval, considering that H3Rs are also located in other neuron types and affect the release of multiple neurotransmitters. In this study, we employed a chemogenetic method to determine whether specifically activating histamine neurons in the tuberomammillary nucleus facilitates memory retrieval. In the novel object recognition test, control mice did not show a preference for objects based on memory 1 week after training, but chemogenetic activation of histamine neurons before testing improved memory retrieval. This selective activation did not affect the locomotor activity or anxiety-related behavior. Administering an H2R antagonist directly into the perirhinal cortex inhibited the recovery of memory retrieval induced by the activation of histamine neurons. Furthermore, we utilized the Barnes maze test to investigate whether chemogenetic activation of histamine neurons influences the retrieval of forgotten spatial memories. Control mice explored all the holes in the maze equally 1 week after training, whereas mice with chemogenetically activated histamine neurons spent more time around the target hole. These findings indicate that chemogenetic activation of histamine neurons in the tuberomammillary nucleus can promote retrieval of seemingly forgotten object recognition and spatial memories.

Evoking episodic and semantic details with instructional manipulation during autobiographical recall.

Older adults tend to describe experiences from their past with fewer episodic details, such as spatiotemporal and contextually specific information, but more nonepisodic details, particularly personal semantic knowledge, than younger adults. While the reduction in episodic details is interpreted in the context of episodic memory decline typical of aging, interpreting the increased production of semantic details is not as straightforward. We modified the widely used Autobiographical Interview (AI) to create a Semantic Autobiographical Interview (SAI) that explicitly targets personal (P-SAI) and general semantic memories (G-SAI) with the aim of better understanding the production of semantic information in aging depending on instructional manipulation. Overall, older adults produced a lower proportion of target details than young adults. There was an intra-individual consistency in the production of target details in the AI and P-SAI, suggesting a trait level in the production of personal target details or consistency in the narrative style and communicative goals adopted across interviews. Older adults consistently produced autobiographical facts and self-knowledge across interviews, suggesting that they are biased toward the production of personal semantic information regardless of instructions. These results cannot be easily accommodated by accounts of aging and memory emphasizing reduced cognitive control or compensation for episodic memory impairment. Nevertheless, future work is needed to fully disentangle between these accounts. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The hippocampus supports precise memory for public events regardless of their remoteness.

The necessity of the human hippocampus and surrounding medial temporal lobe structures to semantic memory remains contentious. Impaired semantic memory following hippocampal lesions could arise either due to partially intertwined episodic memories and/or retrograde/anterograde effects. In this study, we tested amnesic individuals with lesions in hippocampus and surrounding medial temporal lobe (n = 7) and age-matched controls (n = 14) on their ability to precisely recall the dates of famous public events that occurred either before (i.e., pre-lifetime) or after participants' birth date (lifetime). We show that deficits in dating precision are greatest for recent lifetime events, consistent with the notion that recent event memory may be particularly intertwined with episodic memory. At the same time, individuals with medial temporal lobe lesions showed more subtle impairments in their ability to date pre-birth and remote lifetime events precisely. Together, these findings suggest that the hippocampus and surrounding medial temporal lobe structures are important for representational precision of semantic memories regardless of their remoteness.

Developmental refinements to neural attentional state during semantic memory retrieval through adolescence.

Despite the fact that attention undergoes protracted development, little is known about how it may support memory refinements in childhood and adolescence. Here, we asked whether people differentially focus their attention on semantic or perceptual information over development during memory retrieval. First, we trained a multivoxel classifier to characterize whole-brain neural patterns reflecting semantic versus perceptual attention in a cued attention task. We then used this classifier to quantify how attention varied in a separate dataset in which children, adolescents, and adults retrieved autobiographical, semantic, and episodic memories. All age groups demonstrated a semantic attentional bias during memory retrieval, with significant age differences in this bias during the semantic task. Trials began with a preparatory picture cue followed by a retrieval question, which allowed us to ask whether attentional biases varied by trial period. Adults showed a semantic bias earlier during the picture cues, whereas adolescents showed this bias during the question. Adults and adolescents also engaged different brain regions-superior parietal cortex and ventral visual regions, respectively-during preparatory picture cues. Our results demonstrate that retrieval-related attention undergoes refinement beyond childhood. These findings suggest that alongside expanding semantic knowledge, attention-related changes may support the maturation of factual knowledge retrieval.

The late positive event-related potential component is time locked to the decision in recognition memory tasks.

Two event-related potential (ERP) components are commonly observed in recognition memory tasks: the Frontal Negativity (FN400) and the Late Positive Component (LPC). These components are widely interpreted as neural correlates of familiarity and recollection, respectively. However, the interpretation of LPC effects is complicated by inconsistent results regarding the timing of ERP amplitude differences. There are also mixed findings regarding how LPC amplitudes covary with decision confidence. Critically, LPC effects have almost always been measured using fixed time windows relative to memory probe stimulus onset, yet it has not been determined whether LPC effects are time locked to the stimulus or the recognition memory decision. To investigate this, we analysed a large (n = 132) existing dataset recorded during recognition memory tasks with old/new decisions followed by post-decisional confidence ratings. We used ERP deconvolution to disentangle contributions to LPC effects (defined as differences between hits and correct rejections) that were time locked to either the stimulus or the vocal old/new response. We identified a left-lateralised parietal LPC effect that was time locked to the vocal response rather than probe stimulus onset. We also isolated a response-locked, midline parietal ERP correlate of confidence that influenced measures of LPC amplitudes at left parietal electrodes. Our findings demonstrate that, contrary to widespread assumptions, the LPC effect is time locked to the recognition memory decision and is best measured using response-locked ERPs. By extension, differences in response time distributions across conditions of interest may lead to substantial measurement biases when analysing stimulus-locked ERPs. Our findings highlight important confounding factors that further complicate the interpretation of existing stimulus-locked LPC effects as neural correlates of recollection. We recommend that future studies adopt our analytic approach to better isolate LPC effects and their sensitivity to manipulations in recognition memory tasks.