Neurociencias
URI permanente para esta colección
Examinar
Examinando Neurociencias por Materia "CONSOLIDACION DE LA MEMORIA"
Mostrando 1 - 15 de 15
Resultados por página
Opciones de ordenación
Artículo de Publicación Periódica AMPA receptors: A key piece in the puzzle of memory retrieval.(2021) Pereyra, Magdalena; Medina, Jorge Horacio"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"Artículo de Publicación Periódica Behavioral tagging underlies memory reconsolidation(2020-07) Rabinovich Orlandi, Iván; Fullio, Camila L.; Schroeder, Matías Nicolás; Giurfa, Martin; Ballarini, Fabricio; Moncada, Diego"Memory reconsolidation occurs when a retrieving event destabilizes transiently a consolidated memory, triggering thereby a new process of restabilization that ensures memory persistence. Although this phenomenon has received wide attention, the effect of new information cooccurring with the reconsolidation process has been less explored. Here we demonstrate that a memory retrieving event sets a neural tag, which enables the reconsolidation of memory after binding proteins provided by the original or a different contiguous experience. We characterized the specific temporal window during which this association is effective and identified the protein kinase A (PKA) and the extracellular signalregulated kinase 1 and 2 (ERK 1/2) pathways as the mechanisms related to the setting of the reconsolidation tag and the synthesis of proteins. Our results show, therefore, that memory reconsolidation is mediated by a “behavioral tagging” process, which is common to different memory forms. They represent a significant advance in understanding the fate of memories reconsolidated while being adjacent to other events, and provide a tool for designing noninvasive strategies to attenuate (pathological/traumatic) or improve (education-related) memories. "Artículo de Publicación Periódica Differential neurophysiological correlates of retrieval of consolidated and reconsolidated memories in humans: an ERP and pupillometry study(2020-10) Campos-Arteaga, G.; Forcato, Cecilia; Wainstein, G.; Lagos, R.; Palacios-García, I.; Artigas, C.; Morales, R.; Pedreira, María Eugenia; Rodríguez, E."Consolidated memories can return to a labile state if they are reactivated by unpredictable reminders. To persist, active memories must be re-stabilized through a process known as reconsolidation. Although there is consistent behavioral evidence about this process in humans, the retrieval process of reconsolidated memories remains poorly understood. In this context, one fundamental question is whether the same or different neurophysiological mechanisms are involved in retrieval of consolidated and reconsolidated memories. Because it has been demonstrated that the exposure to the reconsolidation process may restructure and strengthen memories, we hypothesized distinct neurophysiological patterns during retrieval of reconsolidated memories. In addition, we hypothesized that interfering with the reconsolidation process using a new learning can prevent these neurophysiological changes. To test it, consolidated, reconsolidated and declarative memories whose reconsolidation process was interfered (i.e., picture-word pairs) were evaluated in humans in an old/new associative recall task while the brain activity and the pupillary response were recorded using electroencephalography and eyetracking. Our results showed that retrieval of reconsolidated memories elicits specific patterns of brain activation, characterized by an earlier peak latency and a smaller magnitude of the left parietal ERP old/new effect compared to memories that were only consolidated or whose reconsolidation process was interfered by a new learning. Moreover, our results demonstrated that only retrieval of reconsolidated memories is associated with a late reversed mid-frontal effect in a 600–690 time window. Complementarily, memories that were reactivated showed an earlier peak latency of the pupil old/new effect compared to non-reactivated memories. These findings support the idea that reconsolidation has an important impact in how memories are retrieved in the future, showing that retrieval of reconsolidated memories is partially supported by specific brain mechanisms."Artículo de Publicación Periódica Dopamine neurotransmission in the VTA regulates aversive memory formation and persistence(2022-09-01) Castillo Díaz, Fernando; Dalto, Juliana F.; Pereyra, Magdalena; Medina, Jorge Horacio"Dopamine (DA) neurons in the ventral tegmental area (VTA) innervating several limbic and neocortical regions of the mammalian brain have long been implicated in motivation, rewarding and aversive behaviors, and memory processing. Recently, we demonstrated that somatodendritic release of DA in the VTA regulates the formation and maintenance of appetitive long-term memories (LTM). However, less is known about the impact of DA neurotransmission in the VTA on aversive LTM. Here, we describe the modulation of negative-valence memories by D1/D5-type DA (D1R)-receptor-mediated neurotransmission in the VTA. As aversive stimuli elicit both active and passive behavioral responses, we used two single-trial aversive training protocols: inhibitory avoidance task and conditioned place aversion. We bilaterally microinfused SCH23390, an antagonist of D1R, into the VTA immediately after training and found that DA neurotransmission in the VTA modulates LTM consolidation and persistence of aversive experiences. Together with previous findings demonstrating that D1R mediated DA neurotransmission in the medial prefrontal cortex and hippocampus is involved in the formation and persistence of LTM for aversive events, our present results indicate that memory processing of environmental stimuli with negative-valence depends on the integration of information mediated by D1R activation in both the VTA region and in selected downstream target areas."Artículo de Publicación Periódica Functional connectivity of anterior retrosplenial cortex in object recognition memory(2021) de Landeta, Ana Belén; Pereyra, Magdalena; Miranda, Magdalena; Bekinschtein, Pedro; Medina, Jorge Horacio; Katche, Cynthia"Recognition memory can rely on three components: “what”, “where” and “when”. Recently we demonstrated that the anterior retrosplenial cortex (aRSC), like the perirhinal cortex (PRH) and unlike the hippocampus (HP), is required for consolidation of the “what” component. Here, we aimed at studying which brain structures interact with the aRSC to process object recognition (OR) memory in rats. We studied the interaction of six brain structures that are connected to the aRSC during OR memory processing: PRH, medial prefrontal cortex (mPFC), anteromedial thalamic nuclei (AM), medial entorhinal cortex (MEC), anterior cingulate cortex (ACC) and the dorsal HP (dHP). We previously described the role of the PRH and dHP, so we first studied the participation of the mPFC, AM, MEC and ACC in OR memory consolidation by bilateral microinfusions of the GABAA receptor agonist muscimol. We observed an impairment in OR long-term memory (LTM) when inactivating the mPFC, the AM and the MEC, but not the ACC. Then, we studied the functional connections by unilateral inactivation of the aRSC and each one of the six structures in the same (ipsilateral) or the opposite (contralateral) hemisphere. Our results showed an amnesic LTM effect in rats with ipsilateral inactivations of aRSC-PRH, aRSC-mPFC, aRSC-AM, or aRSC-MEC. On the other hand, we observed memory impairment when aRSC-ACC were inactivated in opposite hemispheres, and no effect when the aRSC-dHP connection was inactivated. Thus, our ipsilateral inactivation findings reveal that the aRSC and, at least one brain region required in OR LTM processing are essential to consolidate OR memory. In conclusion, our results show that several cortico-cortical and cortico thalamic pathways are important for OR memory consolidation."Artículo de Publicación Periódica Impairment of aversive episodic memories during Covid-19 pandemic: The impact of emotional context on memory processes(2022-06) León, Candela S.; Bonilla, Matías; Urreta Benítez, Facundo A.; Brusco, Luis Ignacio; Wang, Jingyi; Forcato, Cecilia"The threatening context of the COVID-19 pandemic provided a unique setting to study the effects of negative psychological symptoms on memory processes. Episodic memory is an essential function of the human being related to the ability to store and remember experiences and anticipate possible events in the future. Studying this function in this context is crucial to understand what effects the pandemic will have on the formation of episodic memories. To study this, the formation of episodic memories was evaluated by free recall, recognition, and episode order tasks for an aversive and neutral content. The results indicated that aversive episodic memory is impaired both in the free recall task and in the recognition task. Even the beneficial effect that emotional memory usually has for the episodic order was undermined as there were no differences between the neutral and aversive condition. The present work adds to the evidence that indicates that the level of activation does not modify memory processes in a linear way, which also depends on the type of recall and the characteristics of the content to be encoded."Artículo de Publicación Periódica Learning new words: memory reactivation as a mechanism for strengthening and updating a novel word´s meaning(2020-12) Laurino, Julieta; Forcato, Cecilia; Coaker, Nicole; Pedreira, María Eugenia; Kaczer, Laura"In the present study we explored the post-learning changes in a novel word’s definition using a cue-induced memory reactivation. Native speakers of Spanish (N=373) learned low-frequency words with their corresponding definitions. The following day, reactivated groups were exposed to a reminder and provided a subjective assessment of reactivation for each word, while control groups did not receive a reactivation. Study A demonstrated that memory reactivation enhances both explicit recall and semantic integration of new meanings. Study B investigated the effect of memory reactivation in the modification of the new meanings, through three different experiments. Results show an improvement of the updated definitions according to each word´s reactivation strength. In addition, congruence with previous knowledge was found to be a boundary condition, while consolidation time had a positive modulatory effect. Our findings call attention to reactivation as a factor allowing for malleability as well as persistence of long-term memories for words."Artículo de Publicación Periódica Memory reconsolidation as a tool to endure encoding deficits in elderly(2020-08) Tassone, Leonela M.; Urreta Benítez, Facundo A.; Rochon, Delfina; Martínez, Paula B.; Bonilla, Matías; León, Candela S.; Muchnik, Carolina; Solis, Patricia; Medel, Nancy; Kochen, Silvia; Brusco, Luis Ignacio; Moyano, Malen D.; Forcato, Cecilia"Normal aging involves changes in the ability to acquire, consolidate and recall new information. It has been recently proposed that the reconsolidation process is also affected in older adults. Reconsolidation is triggered after reminder presentation, allowing memories to be modified: they can be impaired, strengthened or changed in their content. In young adults it was previously shown that the presentation of repetitive reminders induces memory strengthening one day after reactivation and the presentation of at least one reminder increases memory persistence several days after reactivation. However, until now this process has remained elusive in older adults. We hypothesize that older adults need a stronger reminder to induce memory strengthening through the reconsolidation process than young adults. To test this, we perform a three-day experiment. On day 1, participants learned 15 sound-word associations, on day 2 they received no reminders (NR group), one reminder (R group) or two rounds of reactivations (Rx2 group). Finally, they were tested on day 7. We found that, contrary to our hypothesis, older adults show a memory improvement triggered by repeated labilization/reconsolidation processes to an equal extent than young adults. These results open new perspectives into the use of reconsolidation to improve daily acquired information and the development of therapeutic home used tools to produce memory enhancement in healthy older adults or those with cognitive decline."Artículo de Publicación Periódica Modificación de memorias maladaptativas durante el sueño y la vigilia: una visión interdisciplinaria(2020-11-20) Bonilla, Matías; Jorge, Camila Isabel; Moyano, Malen D.; Forcato, Cecilia"Las memorias consolidadas pueden atravesar por un período de labilidad frente a la presentación de recordatorios (claves ligadas al aprendizaje inicial), seguido de un proceso de re-estabilización conocido como reconsolidación. Por otro lado, el sueño tiene un rol activo en la formación y modificación de memorias, así como en la reducción del tono emocional de las experiencias. Durante el mismo, las nuevas memorias se reactivan, refuerzan e integran a las redes mnésicas preexistentes. Dentro del contexto terapéutico, se pueden evocar memorias antiguas según la necesidad del sujeto, lo que podría estar desencadenando constantes labilizaciones/reestabilizaciones, quizás sin ser conscientes de ello. En la presente revisión bibliográfica discutimos los avances neurocientíficos relacionados a la reactivación y modificación de memorias durante la vigilia y el sueño, así como los últimos desarrollos en terapias psicoterapéuticas para trastornos de ansiedad, con el objetivo de pensar una práctica más interdisciplinaria."Artículo de Publicación Periódica Non-linear susceptibility to interferences in declarative memory formation(2022-06-29) Moyano, Malen D.; Carbonari, Giulia; Bonilla, Matías; Pedreira, María Eugenia; Brusco, Luis Ignacio; Kaczer, Laura; Forcato, Cecilia"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."Artículo de Publicación Periódica Odor cueing during sleep improves consolidation of a history lesson in a school setting(2022-03-22) Vidal, Vanesa; Barbuzza, Alejo R.; Tassone, Leonela M.; Brusco, Luis Ignacio; Ballarini, Fabricio; Forcato, Cecilia"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."Artículo de Publicación Periódica Persistence of spatial memory induced by spaced training involves a behavioral-tagging process(2022-08-10) Correa, Julieta; Tintorelli, Ramiro; Budriesi, Pablo; Viola, Haydeé"Spaced training, which involves long inter-trial intervals, has positive effects on memories. One of the main attributes of long-term memories (LTM) is persistence. Here, to identify the process that promotes LTM persistence by spaced learning, we used the spatial object recognition (SOR) task in rats. The protocol consisted of a first strong training session that induced LTM formation (tested 1 day after training), but not LTM persistence (tested 7 or 14 days after training); and a second weak training session that promoted memory persistence when applied 1 day, but not 7 days, after the first training. We propose that the promotion of memory persistence is based on the Behavioral Tagging (BT) mechanism operating when the memory trace is retrieved. BT involves the setting of a tag induced by learning which gives rise to input selectivity, and the use of plasticity-related proteins (PRPs) to establish the mnemonic trace. We postulate that retraining will mainly retag the sites initially activated by the original learning, where the PRPs needed for memory expression and/or induced by retrieval would be used to maintain a persistent mnemonic trace. Our results suggest that the mechanism of memory expression, but not those of memory reinforcement or reconsolidation, is necessary to promote memory persistence after retraining. The molecular mechanisms involve ERKs1/2 activity to set the SOR learning tag, and the availability of GluA2-containing AMPA receptor. In conclusion, both the synthesis of PRPs and the setting of learning tags are key processes triggered by retraining that allow SOR memory persistence."Artículo de Publicación Periódica Positive and neutral updating reconsolidate aversive episodic memories via different routes(2021-01) Wang, Jingyi; Chen, Boxuan; Sha, Manqi; Gu, Yiran; Wu, Haitao; Forcato, Cecilia; Qin, Shaozheng"Aversive memories are long-lasting and prone to have adverse effects on our emotional wellbeing and mental health. Yet, how to remedy the maladaptive effects of aversive memories remains elusive. Using memory reactivation and emotional updating manipulations, we investigated how positive and neutral emotion updates aversive memories for reconsolidation in humans. We found that positive updating after reactivation was equivalent to neutral updating in altering true memories of the aversive story, but introduced more false memory. Moreover, an additional 12 hours of sleep reconsolidation did not further enlarge true memory differences, but attenuated the effect of reactivation and updating on false memory. Interestingly, the neutral rather than the positive updating reduced the emotional arousal of the aversive memory 24 hours later. Our findings provide novel insights into real-world therapeutic applications regarding how updating with positive and neutral emotion may reshape aversive memories, especially when taking wake- and sleep-filled reconsolidation into account."Artículo de Publicación Periódica Reactivation during sleep with incomplete reminder cues rather than complete ones stabilizes long-term memory in humans(2020-12-04) Forcato, Cecilia; Klinzing, Jens G.; Carbone, Julia; Radloff, Michael; Weber, Frederik D.; Born, Jan; Diekelmann, Susanne"Reactivation by reminder cues labilizes memories during wakefulness, requiring reconsolidation to persist. In contrast, during sleep, cued reactivation seems to directly stabilize memories. In reconsolidation, incomplete reminders are more effective in reactivating memories than complete reminders by inducing a mismatch, i.e. a discrepancy between expected and actual events. Whether mismatch is likewise detected during sleep is unclear. Here we test whether cued reactivation during sleep is more effective for mismatch-inducing incomplete than complete reminders. We first establish that only incomplete but not complete reminders labilize memories during wakefulness. When complete or incomplete reminders are presented during 40-min sleep, both reminders are equally effective in stabilizing memories. However, when extending the retention interval for another 7 hours (following 40-min sleep), only incomplete but not complete reminders stabilize memories, regardless of the extension containing wakefulness or sleep. We propose that, during sleep, only incomplete reminders initiate long-term memory stabilization via mismatch detection."Artículo de Publicación Periódica The effect of zolpidem on targeted memory reactivation during sleep(2021) Carbone, Julia; Bibián, Carlos; Reischl, Patrick; Born, Jan; Forcato, Cecilia; Diekelmann, Susanne"According to the active system consolidation theory, memory consolidation during sleep relies on the reactivation of newly encoded memory representations. This reactivation is orchestrated by the interplay of sleep slow oscillations, spindles, and theta, which are in turn modulated by certain neurotransmitters like GABA to enable long-lasting plastic changes in the memory store. Here we asked whether the GABAergic system and associated changes in sleep oscillations are functionally related to memory reactivation during sleep. We administered the GABAA agonist zolpidem (10 mg) in a double-blind placebo-controlled study. To specifically focus on the effects on memory reactivation during sleep, we experimentally induced such reactivations by targeted memory reactivation (TMR) with learning-associated reminder cues presented during post-learning slow-wave sleep (SWS). Zolpidem significantly enhanced memory performance with TMR during sleep compared with placebo. Zolpidem also increased the coupling of fast spindles and theta to slow oscillations, although overall the power of slow spindles and theta was reduced compared with placebo. In an uncorrected exploratory analysis, memory performance was associated with slow spindle responses to TMR in the zolpidem condition, whereas it was asso ciated with fast spindle responses in placebo. These findings provide tentative first evidence that GABAergic activity may be functionally implicated in memory reactivation processes during sleep, possibly via its effects on slow oscillations, spindles and theta as well as their interplay."