Banca de DEFESA: DANIEL GOMES DE ALMEIDA FILHO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : DANIEL GOMES DE ALMEIDA FILHO
DATA : 25/02/2019
HORA: 09:00
LOCAL: INSTITUTO DO CEREBRO
TÍTULO:

Corticalization of hippocampal-dependent memory during REM sleep - Investigating different time windows after learning

PALAVRAS-CHAVES:

corticalization, REM sleep, contextual fear conditioning, phasic REM, memory consolidation, retrosplenial cortex, Granger causality

PÁGINAS: 207
GRANDE ÁREA: Ciências Biológicas
ÁREA: Fisiologia
RESUMO:

Sleep and memory are two essential aspects of the life of most living beings. During sleep we rest our muscles and our internal organs, reduce energy expenditure, recover our immune system, and clean our brains from metabolites; everything necessary to prepare our body for the next day of experiences. Simultaneously, memory is a cognitive function that allows us to characterize patterns, store them, build and develop ideas, and define who we are. Interestingly, the last decades of research had led to the notion that these two important physiological processes may keep holding hands, i.e., that the sleep function on memory is not merely by cleaning unnecessary information and passively helping by increasing the signal-to-noise ratio. The new evidence suggest a protagonism of sleep in actively working on memory processing. Besides the plentiful evidence implicating a specific phase of sleep called non-rapid eye movement (NREM) in memory consolidation, the present work focus on understanding the mechanism by which REM sleep benefits hippocampal-dependent memory processing. We have gone into an extensive review of the literature, collaborations, designing, performing, and analyzing experiments aiming at step forward in the understanding the role of REM sleep in the process of making hippocampal-dependent memories persist and gradually depend on neocortical structures (corticalization) over time. Our results indicate that there are special time windows for REM sleep-dependent plasticity and memory corticalization after learning, with particular attention to an early window 3 – 4h after training and a late one about 12h after. We show evidence of an interplay between the hippocampus and the retrosplenial cortex (two regions closely related to memory processing) during REM sleep, and that this interplay in the early window is correlated with memory expression. We also exhibit evidence that the upregulation of genes related to synaptic plasticity during the late time window, which have been consistently implicated in memory persistence, may depend on REM sleep. Altogether, the results reported in the present work support the notion that windows of REM sleep after training are important for offline memory processing and corticalization. They also suggest that the mechanisms of REM sleep action comprise the cross-talk between memory-related cortical and subcortical regions, and to provide training-induced gene expression necessary for the optimized remodeling of cortical networks for the introduction of new information into preexisting knowledge

MEMBROS DA BANCA:
Presidente - 1660044 - SIDARTA TOLLENDAL GOMES RIBEIRO
Interno - 1721223 - ADRIANO BRETANHA LOPES TORT
Interno - 1939184 - SANDRO JOSE DE SOUZA
Externo à Instituição - KOICHI SAMESHIMA - USP
Externo à Instituição - MÁRCIO FLÁVIO DUTRA MORAES - UFMG