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Benzodiazepines are commonly used drugs to treat anxiety in crime witnesses. These increase GABA inhibitory effects, which impairs aversive memory encoding and consolidation. Eyewitness memory is essential in justice. However, memory is malleable leading to false memories that could cause a selection of an innocent in a lineup. Here, we studied whether a low dose of Clonazepam impairs memory encoding as well as consolidation of faces and narrative of the event. We performed two experiments using a double-blind and between subject design (N = 216). Day 1: subjects watched a crime video and received Clonazepam 0.25 mg (CLZ group) or placebo (PLC group) before (Exp. 1) or after the video (Exp. 2) to assess the effect on encoding and consolidation. One week later, the memory was assessed using a present and absent target lineup and asking for a free recall. Regarding encoding, we found that in the CLZ group memory was impaired in the free recall task, while no differences were found for recognition memory. Regarding consolidation, we did not observe memory measures that were affected by this dose of benzodiazepines. The results suggest that while some aspects of eyewitness memory could be modulated even with low doses of benzodiazepine, others could not be affected. More studies should be performed with higher doses of CLZ similar to those administered in real life. These results are relevant in the judicial field to assess the reliability of the eyewitness elections under the effects of this drug.

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Episodic memory is essential to navigate in a changing environment by recalling past events, creating new memories, and updating stored information from experience. Although the mechanisms for acquisition and consolidation have been profoundly studied, much less is known about memory retrieval. Hippocampal spatial representations are key for retrieval of contextually guided episodic memories. Indeed, hippocampal place cells exhibit stable location-specific activity which is thought to support contextual memory, but can also undergo remapping in response to environmental changes. It is unclear if remapping is directly related to the expression of different episodic memories. Here, using an incidental memory recognition task in rats, we showed that retrieval of a contextually guided memory is reflected by the levels of CA3 remapping, demonstrating a clear link between external cues, hippocampal remapping, and episodic memory retrieval that guides behavior. Furthermore, we describe NMDARs as key players in regulating the balance between retrieval and memory differentiation processes by controlling the reactivation of specific memory traces. While an increase in CA3 NMDAR activity boosts memory retrieval, dentate gyrus NMDAR activity enhances memory differentiation. Our results contribute to understanding how the hippocampal circuit sustains a flexible balance between memory formation and retrieval depending on the environmental cues and the internal representations of the individual. They also provide new insights into the molecular mechanisms underlying the contributions of hippocampal subregions to generate this balance.

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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)

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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.

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The prestige theory of evolution states that our memory has an intrinsic bias to memorize information from someone of prestige. However, the evidence for information recall is mainly focused on content bias. Considering that the prestige bias can be advantageous in selecting information in contexts of uncertainty, this study assessed whether, in the scenario of the COVID-19 pandemic, the prestige bias would be favored over other models that do not possess the prestige spirit characteristics. The study was conducted through an online experiment, where participants were subjected to reading fictitious text, followed by a surprise recollection. Data were analyzed using a generalized linear mixed model, Poisson family, and logistic regression. The results showed that prestige is only prioritized in the recall due to the family model and does not present any difference from the other models tested. However, it influenced the recall of specific information, suggesting its role as a factor of cultural attraction. Furthermore, we observed that trust in science-oriented profiles can influence the recall of information during a health crisis. Finally, this study highlights the complexity of the functioning of the human mind and how several factors can act simultaneously in the recall of information.

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While foraging, animals have to find potential food sites, remember these sites, and plan the best navigation route. To deal with problems associated with foraging for multiple and patchy resources, primates may employ heuristic strategies to improve foraging success. Until now, no study has attempted to investigate experimentally the use of such strategies by a primate in a context involving foraging in large-scale space. Thus, we carried out an experimental field study that aimed to test if wild common marmosets (Callithrix jacchus) employ heuristic strategies to efficiently navigate through multiple feeding sites distributed in a large-scale space. In our experiment, we arranged four feeding platforms in a trapezoid configuration with up to 60 possible routes and observe marmosets' decisions under two experimental conditions. In experimental condition I, all platforms contained the same amount of food; in experimental condition II, the platforms had different amounts of food. According to the number and arrangement of the platforms, we tested two heuristic strategies: the Nearest Neighbor Rule and the Gravity Rule. Our results revealed that wild common marmosets prefer to use routes consistent with a heuristic strategy more than expected by chance, regardless of food distribution. The findings also demonstrate that common marmosets seem to integrate different factors such as distance and quantity of food across multiple sites distributed over a large-scale space, employing a combination of heuristic strategies to select the most efficient routes available. In summary, our findings confirm our expectations and provide important insights into the spatial cognition of these small neotropical primates.

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Fear conditioning is encoded by strengthening synaptic connections between the neurons activated by a conditioned stimulus (CS) and those activated by an unconditioned stimulus (US), forming a memory engram, which is reactivated during memory retrieval. In temporal associations, activity within the prelimbic cortex (PL) plays a role in sustaining a short-term, transient memory of the CS, which is associated with the US after a temporal gap. However, it is unknown whether the PL has only a temporary role, transiently representing the CS, or is part of the neuronal ensembles that support the retrieval, i.e., whether PL neurons support both transient, short-term memories and stable, long-term memories. We investigated neuronal ensembles underlying temporal associations using fear conditioning with a 5-s interval between the CS and US (CFC-5s). Controls were trained in contextual fear conditioning (CFC), in which the CS-US overlaps. We used Robust Activity Marking (RAM) to selectively manipulate PL neurons activated by CFC-5s learning and Targeted Recombination in Active Populations (TRAP2) mice to label neurons activated by CFC-5s learning and reactivated by memory retrieval in the amygdala, medial prefrontal cortex, hippocampus, perirhinal cortices (PER) and subiculum. We also computed their co-reactivation to generate correlation-based networks. The optogenetic reactivation or silencing of PL encoding ensembles either promoted or impaired the retrieval of CFC-5s but not CFC. CFC-5s retrieval reactivated encoding ensembles in the PL, PER, and basolateral amygdala. The engram network of CFC-5s had higher amygdala and PER centralities and interconnectivity. The same PL neurons support learning and stable associative memories.

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All experiences preserved within episodic memory contain information on the space and time of events. The hippocampus is the main brain region involved in processing spatial and temporal information for incorporation within episodic memory representations. However, the other brain regions involved in the encoding and retrieval of spatial and temporal information within episodic memory are unclear, because a systematic review of related studies is lacking and the findings are scattered. The present study was designed to integrate the results of functional magnetic resonance imaging and positron emission tomography studies by means of a systematic review and meta-analysis to provide converging evidence. In particular, we focused on identifying the brain regions involved in the retrieval of spatial and temporal information. We identified a spatial retrieval network consisting of the inferior temporal gyrus, parahippocampal gyrus, superior parietal lobule, angular gyrus, and precuneus. Temporal context retrieval was supported by the dorsolateral prefrontal cortex. Thus, the retrieval of spatial and temporal information is supported by different brain regions, highlighting their different natures within episodic memory.

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Autobiographical memory and personal life stories are typically conceived as memories about the self. However, personal life stories often contain information about important events from other people's lives. Sometimes those memories become an important part of our own life stories, illuminating the role that other people play in remembering our personal past. In this study, we examined the extent to which memories of important life story events are self-focused (e.g., I moved to Japan) or other-focused (e.g., My child graduated from college). Participants from Mexico, Greenland, China, Denmark and the United States recalled and dated seven autobiographical memories of important personal life story events. Participants also rated the memories for importance and emotional valence. The memories were coded as self- or other-focused. Participants recalled mainly self-focused memories. However, Danish and Chinese participants recalled about 20% other-focused memories. Danish participants recalled negative events about their parents, whereas Chinese participants recalled positive events about their children. Self-focused and other-focused memories differed in their emotional valence and lifespan distribution, but not in importance. The findings show that individuals remember other-focused memories and also incorporate them into their own personal life stories. Conceptual implications for autobiographical memory are discussed.

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