小柯机器人

美国洛克菲勒大学Priyamvada Rajasethupathy及其团队发现前额叶特征可表征驱动记忆回忆。这一研究成果发表在2022年7月13日出版的国际学术期刊《自然》上。

为了深入了解如何诱导记忆回忆，研究人员开发了一项行为任务，其中小鼠使用特征来回忆相关的记忆。当小鼠执行这项任务时，研究人员在海马体中进行了纵向成像，并确定了全局相关的稳健表示，而不是单个特征的稳健表示。为了鉴别为海马体提供特征输入的假定大脑区域，研究在行为过程中对海马体进行成像时抑制了皮质信号的传入。研究发现，虽然抑制内嗅皮层导致海马体的广泛沉默，但前额叶前扣带回的抑制导致相关神经元的高度特异性沉默和基于特征的回忆缺陷。

接下来，研究人员开发了一种在行为过程中同时对前扣带回和海马进行成像的流程，其可以表征前扣带回特异群体水平的特征，这些特征在训练期间滞后海马相关表示，但在记忆回忆时动态重组以识别和招募海马中的相关集合。该研究提供了第一个关于相关记忆在大脑中的位置信息、它们如何出现以及它们如何访问远程情景以驱动记忆回忆的机制见解。

据了解，记忆形成涉及将相关特征整合为单一表示，而使用这些相关特征的部分组合就能驱动记忆回忆。相关记忆与其组成特征之间关系的神经基础尚未得到完全揭示。特别是，特征在大脑中的代表位置以及它们如何驱动回忆。

附：英文原文

Title: Prefrontal feature representations drive memory recall

Author: Yadav, Nakul, Noble, Chelsea, Niemeyer, James E., Terceros, Andrea, Victor, Jonathan, Liston, Conor, Rajasethupathy, Priyamvada

Issue&Volume: 2022-07-13

Abstract: Memory formation involves binding of contextual features into a unitary representation1,2,3,4, whereas memory recall can occur using partial combinations of these contextual features. The neural basis underlying the relationship between a contextual memory and its constituent features is not well understood; in particular, where features are represented in the brain and how they drive recall. Here, to gain insight into this question, we developed a behavioural task in which mice use features to recall an associated contextual memory. We performed longitudinal imaging in hippocampus as mice performed this task and identified robust representations of global context but not of individual features. To identify putative brain regions that provide feature inputs to hippocampus, we inhibited cortical afferents while imaging hippocampus during behaviour. We found that whereas inhibition of entorhinal cortex led to broad silencing of hippocampus, inhibition of prefrontal anterior cingulate led to a highly specific silencing of context neurons and deficits in feature-based recall. We next developed a preparation for simultaneous imaging of anterior cingulate and hippocampus during behaviour, which revealed robust population-level representation of features in anterior cingulate, that lag hippocampus context representations during training but dynamically reorganize to lead and target recruitment of context ensembles in hippocampus during recall. Together, we provide the first mechanistic insights into where contextual features are represented in the brain, how they emerge, and how they access long-range episodic representations to drive memory recall.

DOI: 10.1038/s41586-022-04936-2

Source: https://www.nature.com/articles/s41586-022-04936-2

Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html