题    目(TITLE): The role of sleep in memory consolidatio 讲座人(SPEAKER): 魏依娜，研究员，之江实验室 主持人(CHAIR): 蒋田仔，研究员，中科院自动化研究所   时    间(TIME): 2022年3月9日，上午09:30-10:30  （腾讯会议号：648 197 745） 地    点(VENUE): 智能化大厦五层会议室

We spend a third of our lives sleeping. During sleep, although human and animal brains are decoupled from the external sensory input, brain activity remains high and varies across sleep stages. It is believed that one of the important sleep functions is the consolidation of recent memories to organize them for long-term storage. Nevertheless, the specific mechanisms of how different sleep stages contribute to memory consolidation are poorly understood. In this study, using a realistic computational model of the thalamocortical network, we tested the role of different Non-Rapid Eye Movement (NREM) sleep stages in memory consolidation. We found that sleep spindles (the hallmark of N2 stage sleep) and slow oscillations (the hallmark of N3 stage sleep) both promote replay of the spike sequences learned in the awake state and replay was localized at the trained network locations. Memory performance improved after a period of NREM sleep but not after the same time period in awake. When multiple memories were trained, the local nature of the spike sequence replay during spindles allowed replay of the distinct memory traces independently, while slow oscillations promoted competition that could prevent replay of the weak memories in a presence of the stronger memory traces. This could lead to extinction of the weak memories unless when sleep spindles (N2 sleep) preceded slow oscillations (N3 sleep), as observed during the natural sleep cycle. Our study presents a mechanistic explanation for the role of sleep rhythms in memory consolidation and proposes a testable hypothesis how the natural structure of sleep stages provides an optimal environment to consolidate memories. 

个人简介 （Biography）