Offline ensemble co-reactivation links memories across days

• 成果类型: Article
• 署名作者: Zaki, Yosif; Pennington, Zachary T.; Morales-Rodriguez, Denisse; Bacon, Madeline E.; Ko, BumJin; Francisco, Taylor R.; LaBanca, Alexa R.; Sompolpong, Patlapa; Dong, Zhe; Lamsifer, Sophia; Chen, Hung-Tu; Segura, Simon Carrillo; Wick, Zoe Christenson; Silva, Alcino J.; Rajan, Kanaka; van der Meer, Matthijs; Fenton, Andre; Shuman, Tristan; Cai, Denise J.
• 署名单位: Icahn School of Medicine at Mount Sinai; Dartmouth College; New York University; New York University Tandon School of Engineering; University of California System; University of California Los Angeles; New York University; NYU Langone Medical Center
• 刊物名称: Nature
• ISSN/ISSBN: 0028-1393
• DOI: 10.1038/s41586-024-08168-4
• 发表日期: 2025-01-02
• 关键词: replay; hippocampus; COMPETITION; experience; SEQUENCES; time

摘要

Memories are encoded in neural ensembles during learning1-6 and are stabilized by post-learning reactivation7-17. Integrating recent experiences into existing memories ensures that memories contain the most recently available information, but how the brain accomplishes this critical process remains unclear. Here we show that in mice, a strong aversive experience drives offline ensemble reactivation of not only the recent aversive memory but also a neutral memory formed 2 days before, linking fear of the recent aversive memory to the previous neutral memory. Fear specifically links retrospectively, but not prospectively, to neutral memories across days. Consistent with previous studies, we find that the recent aversive memory ensemble is reactivated during the offline period after learning. However, a strong aversive experience also increases co-reactivation of the aversive and neutral memory ensembles during the offline period. Ensemble co-reactivation occurs more during wake than during sleep. Finally, the expression of fear in the neutral context is associated with reactivation of the shared ensemble between the aversive and neutral memories. Collectively, these results demonstrate that offline ensemble co-reactivation is a neural mechanism by which memories are integrated across days. In mice, a strong aversive experience drives offline ensemble reactivation of not only the recent aversive memory but also a neutral memory formed 2 days before, linking fear of the recent aversive memory to the previous neutral memory.