系统巩固重组海马印痕电路，这一成果由加拿大多伦多大学Paul W. Frankland课题组经过不懈努力而取得。这一研究成果于2025年5月14日发表在国际顶尖学术期刊《自然》上。

在这里，课题组人员报告了海马印痕电路的时间依赖性重组足以解释与系统巩固相关的记忆精度的变化。通过在小鼠身上使用印痕标记工具，研究小组证明了时间的流逝会重新连接海马印痕回路，使海马印痕神经元在与原始训练条件不匹配的相关情况下混杂地活跃并指导行为。重组依赖于海马体神经发生；消除海马神经发生会阻止重组并维持精确的事件记忆。相反，促进海马体神经发生会加速记忆重组和海马体中与事件相关的主要记忆的出现。他们的研究结果表明，系统整合模型需要更新，以解释海马体内部的重组，从而导致记忆精度的定性变化。

据悉，情景记忆——最初依赖海马体的事件的高保真记忆——并不能永远保持其准确性。这种与时间相关的精确度损失的一个好处是出现了与事件相关的要点记忆，这些要点记忆可能是在新的但相关的情况下指导未来行为的主题（即泛化）。系统巩固模型提出，记忆重组伴随着记忆精度的丧失；然而，这次重组的地点尚不清楚。

附：英文原文

Title: Systems consolidation reorganizes hippocampal engram circuitry

Author: Ko, Sangyoon Y., Rong, Yiming, Ramsaran, Adam I., Chen, Xiaoyu, Rashid, Asim J., Mocle, Andrew J., Dhaliwal, Jagroop, Awasthi, Ankit, Guskjolen, Axel, Josselyn, Sheena A., Frankland, Paul W.

Issue&Volume: 2025-05-14

Abstract: Episodic memories—high-fidelity memories for events that depend initially on the hippocampus—do not maintain their precision in perpetuity. One benefit of this time-dependent loss of precision is the emergence of event-linked gist memories that may be used to guide future behaviour in new but related situations (that is, generalization)1,2,3. Models of systems consolidation propose that memory reorganization accompanies this loss of memory precision1,4; however, the locus of this reorganization is unclear. Here we report that time-dependent reorganization of hippocampal engram circuitry is sufficient to explain shifts in memory precision associated with systems consolidation. Using engram labelling tools in mice, we demonstrate that the passage of time rewires hippocampal engram circuits, enabling hippocampal engram neurons to be promiscuously active and guide behaviour in related situations that do not match the original training conditions. Reorganization depends on hippocampal neurogenesis; eliminating hippocampal neurogenesis prevents reorganization and maintains precise, event memories. Conversely, promoting hippocampal neurogenesis accelerates memory reorganization and the emergence of event-linked gist memories in the hippocampus. Our results indicate that systems consolidation models require updating to account for within-hippocampus reorganization that leads to qualitative shifts in memory precision.

DOI: 10.1038/s41586-025-08993-1

Source: https://www.nature.com/articles/s41586-025-08993-1