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- ÍtemDopamine D1/D5 receptors in the restrosplenial cortex are necessary to consolidate object recognition memory(2022-07-22)"The retrosplenial cortex (RSC) has been widely related to spatial and contextual memory. However, we recently demonstrated that the anterior part of the RSC (aRSC) is required for object recognition (OR) memory consolidation. In this study, we aimed to analyze the requirement of dopaminergic inputs into the aRSC for OR memory consolidation in male rats. We observed amnesia at 24-h long-term memory when we infused SCH23390, a D1/D5 dopamine receptors antagonist, into aRSC immediately after OR training session. However, the same infusion had no effect on OR short-term memory. Then, we analyzed whether the ventral tegmental area (VTA) is necessary for OR consolidation. VTA inactivation by intra-VTA administration of muscimol, a GABAA agonist, immediately after an OR training session induced amnesia when animals were tested at 24 h. Moreover, we observed that this VTA inactivation-induced amnesia was reversed by the simultaneous intra-aRSC delivery of SKF38393, a D1/D5 receptor agonist. Altogether, our results suggest that VTA dopaminergic inputs to aRSC play an important modulatory role in OR memory consolidation."
- ÍtemNon-linear susceptibility to interferences in declarative memory formation(2022-06-29)"After encoding, memories go through a labile state followed by a stabilization process known as consolidation. Once consolidated they can enter a new labile state after the presentation of a reminder of the original memory, followed by a period of re-stabilization (reconsolidation). During these periods of lability the memory traces can be modified. Currently, some studies show a rapid stabilization after 30 min, while others show that stabilization occurs after longer periods (e.g. > 6 h). Here we investigate the effect of an interference treatment on declarative memory consolidation, comparing distinct time intervals after acquisition. On day 1, participants learned a list of non- syllable pairs (List 1). 5 min, 30 min, 3 h or 8 h later, they received an interference list (List 2) that acted as an amnesic agent. On day 2 (48 h after training) participants had to recall List 1 first, followed by List 2. We found that the List 1 memory was susceptible to interference when List 2 was administered 5 min or 3 h after learning but not when it was administered 30 min or 8 h after. We propose the possibility that this rapid memory protection could be induced by a fast and transient neocortical integration. Our results open a discussion about the contribution of molecular and systemic aspects to memory consolidation."
- ÍtemOdor cueing during sleep improves consolidation of a history lesson in a school setting(2022-03-22)"Sleep is a key factor in memory consolidation. During sleep, information is reactivated, transferred, and redistributed to neocortical areas, thus favoring memory consolidation and integration. Although these reactivations occur spontaneously, they can also be induced using external cues, such as sound or odor cues, linked to the acquired information. Hence, targeted memory reactivation during sleep represents an advantageous tool for improving memory consolidation in real-life settings. In this study, our goal was to improve the consolidation of complex information such as that of a history lesson, using a school study session in the presence of an odor, and a reactivation round while sleeping at home on the same night of the acquisition, without using additional study sessions. We found that complex information can be associated with an odor in the classroom and that one session of reactivation during the frst night of sleep in the students’ houses improves its consolidation. These results bring new evidence for the implementation of reactivation during sleep in real-life settings."
- ÍtemIdentification performance during quarantine by COVID-19 pandemic: Influence of emotional variables and sleep quality(2021)"The COVID-19 pandemic has caused major disruptions in people’s lives around the globe. Sleep habits and emotional balance have been disturbed in a way that could be comparable to the havoc caused by a deep personal crisis or a traumatic experience. This unfortunate situation provides a unique context in which to study the impact of these imbalances on cognitive processes. In particular, the field of eyewitness science could benefit from these conditions, since they are also often present in crime victims, but can only be generated in the laboratory up to a certain ethical and practical limit. For several decades, eyewitness studies have tried to discover what variables affect people’s ability to properly recognize faces. However, the disparity of experimental designs and the limitations of laboratory work could be contributing to the lack of consensus around several factors, such as sleep, anxiety, and depression. Therefore, the possibility of observing the influence of these agents in natural contexts could shed light on this discussion. Here, we perform simple and repeated lineups with witnesses of mock-crime, considering the conditions related to the COVID-19 pandemic, which to some extent allow emulating the deterioration in general well-being that often afflicts crime victims. For this, 72 participants completed symptomatology scales, and watched a video portraying a staged violent episode. Subsequently, they gave testimony and participated in two lineups, in which we manipulated the presence/absence of the perpetrator, to recreate critical scenarios for the appearance of false recognitions. We found an increase in recognition errors in those individuals who did not have access to the perpetrator during the Initial lineup. Additionally, the conditions of the pandemic appear to have adversely affected the ability to witness and accurately perform lineups. These results reaffirm the need to move toward the standardization of research practices and methods for assessing testimonial evidence, especially in relation to the results of the lineups. Considering the degree of fallibility of these processes can lead to a reduction of wrongful convictions."
- ÍtemAMPA receptors: A key piece in the puzzle of memory retrieval.(2021)"Retrieval constitutes a highly regulated and dynamic phase in memory processing. Its rapid temporal scales require a coordinated molecular chain of events at the synaptic level that support transient memory trace reactivation. AMPA receptors (AMPAR) drive the majority of excitatory transmission in the brain and its dynamic features match the singular fast timescales of memory retrieval. Here we provide a review on AMPAR contribution to memory retrieval regarding its dynamic movements along the synaptic compartments, its changes in receptor number and subunit composition that take place in activity dependent processes associated with retrieval. We highlight on the differential regulations exerted by AMPAR subunits in plasticity processes and its impact on memory recall"