美国哥伦比亚大学医学中心Andres D. Grosmark研究组发现重新激活可预测无偏的长期认知地图巩固。相关论文发表在2021年10月18日出版的《自然—神经科学》杂志上。

他们采用同步快速钙成像和电生理学来追踪 2 周以上的“在线”空间奖励学习行为和“离线”静止的海马位置细胞。他们描述了持续网络级离线重新激活小鼠空间体验的招募预测了位置细胞在其在线恢复前几天的未来表征稳定性。此外，虽然奖励相邻位置的表示通常在几天内更稳定，但相反，与离线重新激活相关的稳定性对于奖励远端位置最为突出。因此，虽然发生在几十毫秒的时间尺度上，但离线重新激活与多日表示的稳定性独特相关，该表示可以抵消整体奖励邻接偏差，从而预测全面反映整个潜在空间背景的认知地图的稳定性。这些发现表明，与在线编码相比，学习后离线相关的记忆巩固在学习中起着互补和计算上不同的作用。

研究人员表示，可以持续一生的空间记忆被认为是在在线探索期间编码的，随后通过离线重新激活整合为稳定的认知地图。然而，离线重新激活稳定持久空间表示的机制和计算原理仍然知之甚少。

附：英文原文

Title: Reactivation predicts the consolidation of unbiased long-term cognitive maps

Author: Grosmark, Andres D., Sparks, Fraser T., Davis, Matt J., Losonczy, Attila

Issue&Volume: 2021-10-18

Abstract: Spatial memories that can last a lifetime are thought to be encoded during ‘online’ periods of exploration and subsequently consolidated into stable cognitive maps through their ‘offline’ reactivation. However, the mechanisms and computational principles by which offline reactivation stabilize long-lasting spatial representations remain poorly understood. Here, we employed simultaneous fast calcium imaging and electrophysiology to track hippocampal place cells over 2 weeks of online spatial reward learning behavior and offline resting. We describe that recruitment to persistent network-level offline reactivation of spatial experiences in mice predicts the future representational stability of place cells days in advance of their online reinstatement. Moreover, while representations of reward-adjacent locations are generally more stable across days, offline-reactivation-related stability is, conversely, most prominent for reward-distal locations. Thus, while occurring on the tens of milliseconds timescale, offline reactivation is uniquely associated with the stability of multiday representations that counterbalance the overall reward-adjacency bias, thereby predicting the stabilization of cognitive maps that comprehensively reflect entire underlying spatial contexts. These findings suggest that post-learning offline-related memory consolidation plays a complimentary and computationally distinct role in learning compared to online encoding.

DOI: 10.1038/s41593-021-00920-7

Source: https://www.nature.com/articles/s41593-021-00920-7