The hippocampus and the amygdala are two structures required for emotional memory. While the hippocampus encodes the contextual part of the memory, the amygdala processes its emotional valence. During Non-REM sleep, the hippocampus displays high frequency oscillations called “ripples”. Our early work shows that the suppression of ripples during sleep impairs performance on a spatial task, underlying their crucial role in memory consolidation. We more recently showed that the joint amygdala-hippocampus activity linked to aversive learning is reinstated during the following Non-REM sleep epochs, specifically during ripples. This mechanism potentially sustains the consolidation of aversive associative memories during Non REM sleep. On the other hand, REM sleep is associated with regular 8 Hz theta oscillations, and is believed to play a role in the regulation of emotional reactions and the consolidation of emotional memories (emotional processing). Unraveling the fine neuronal dynamics related to REM sleep, Non-REM sleep and the transitions between states in the hippocampus-amygdala network will further our understanding of the implication of these sleep stages and related brain patterns in emotional processing.
Also available through Zoom:https://unil.zoom.us/j/2341931984