Hippocampus-retrosplenial cortex interaction is increased during phasic REM and contributes to memory consolidation

• Autor(a) principal: Almeida Filho, Daniel Gomes de
• Data de Publicação: 2021
• Outros Autores: Koike, Bruna Del Vechio, Billwiller, Francesca, Farias, Kelly Soares, Sales, Igor Rafael Praxedes de, Luppi, Pierre-Hervé, Ribeiro, Sidarta Tollendal Gomes, Queiroz, Claudio Marcos Teixeira de
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/handle/123456789/32768
• topic: Hippocampus; Theta rhythm; Sleep, REM; Spatial learning; Gyrus cinguli

Hippocampal (HPC) theta oscillation during post-training rapid eye movement (REM) sleep supports spatial learning. Theta also modulates neuronal and oscillatory activity in the retrosplenial cortex (RSC) during REM sleep. To investigate the relevance of theta-driven interaction between these two regions to memory consolidation, we computed the Granger causality within theta range on electrophysiological data recorded in freely behaving rats during REM sleep, both before and after contextual fear conditioning. We found a training-induced modulation of causality between HPC and RSC that was correlated with memory retrieval 24 h later. Retrieval was proportional to the change in the relative influence RSC exerted upon HPC theta oscillation. Importantly, causality peaked during theta acceleration, in synchrony with phasic REM sleep. Altogether, these results support a role for phasic REM sleep in hippocampo-cortical memory consolidation and suggest that causality modulation between RSC and HPC during REM sleep plays a functional role in that phenomenon