Deconstruction of a Memory Engram Reveals Distinct Ensembles Recruited at Learning

Overview

Journal bioRxiv

Date 2024 Dec 23

PMID 39713328

Authors

Clement Pouget

Flora Morier

Nadja Treiber

Pablo Fernandez Garcia

Nina Mazza

Run Zhang

Isaiah Reeves

Stephen Winston

Mark A Brimble

Christina K Kim

Gisella Vetere

Affiliations

Soon will be listed here.

Abstract

How are associative memories formed? Which cells represent a memory, and when are they engaged? By visualizing and tagging cells based on their calcium influx with unparalleled temporal precision, we identified non-overlapping dorsal CA1 neuronal ensembles that are differentially active during associative fear memory acquisition. We dissected the acquisition experience into periods during which salient stimuli were presented or certain mouse behaviors occurred and found that cells associated with specific acquisition periods are sufficient alone to drive memory expression and contribute to fear engram formation. This study delineated the different identities of the cell ensembles active during learning, and revealed, for the first time, which ones form the core engram and are essential for memory formation and recall.

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