Neurociencias
Permanent URI for this community
Browse
Browsing Neurociencias by Subject "APRENDIZAJE"
Now showing 1 - 6 of 6
Results Per Page
Sort Options
artículo de publicación periódica.listelement.badge 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.listelement.badge 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."póster.listelement.badge Non-linear susceptibility to interferences in declarative memory formation(2021) Moyano, Malen D.; Carbonari, Giulia; Bonilla, Matías; Brusco, Luis Ignacio; Pedreira, María Eugenia; Kaczer, Laura; Forcato, Cecilia"After encoding, memories are in 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 (cue) of the original memory, followed by a period of re-stabilization (reconsolidation). In both processes, once stabilization/re-stabilization is accomplished the memory cannot be modified. Currently there are studies that show a rapid stabilization after 30 min, while others studies show that stabilization occurs after 6h. However, there are no studies evaluating short and long delays simultaneously. Knowing that there are spontaneous waves of destabilization (without the re-exposure to keys linked to learning) on which the consolidation and memory persistence depends, here we investigate whether declarative memories in humans go through spontaneous abilization/stabilization processes after learning or if they only pass through a single time window of lability."artículo de publicación periódica.listelement.badge 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."póster.listelement.badge The role of sleep in episodic memory reconsolidation: project and preliminary results(2021) Moyano, Malen D.; Tassone, Leonela M.; Brusco, Luis Ignacio; Wang, Jingyi; Forcato, Cecilia“Episodic memory is a subtype of declarative memory, defined as the ability to remember how, where and when past events occurred. Consolidated memories can be reactivated by a reminder of the original memory and can enter a new labile state, followed by a period of re-stabilization (reconsolidation). Sleep facilitates the consolidation of newly encoded memories and enhances the memory persistence 6 months after learning. It was demonstrated that a short nap accelerated memory re-stabilization of a list of nonsense syllable pairs, and facilitated the reconsolidation of the reactivated object-location memory, at short-term. Here, we aim to study the role of sleep on memory persistence of a neutral episodic memory through the reconsolidation process.”póster.listelement.badge Word learning and semantic integration: memory reactivation as a key mechanism for building the mental lexicon(2020) Laurino, Julieta; Forcato, Cecilia; Pedreira, María Eugenia; Kaczer, Laura"Analyze the contribution of memory reactivation to the enhancement and updating of words’ meaning. Our hypothesis is that reactivating a novel word´s meaning could be a key mechanism for its lexical integration and plasticity."