Memory Replay in the Hippocampus

Chapter

Abstract

The hippocampus is required for the encoding, consolidation, and retrieval of episodic memories, but the neural mechanisms underlying these processes are still not well understood. Apart from place field activity, hippocampal neurons exhibit replay of past experience during sharp-wave ripples (SWRs), which involve sequential reactivation of hippocampal place cells representing previously experienced behavioral trajectories on a fast timescale. Replay during SWRs occurs both during slow-wave sleep and in the awake state, especially during periods of relative immobility. Repetition of stored memory patterns on a compressed timescale during replay is ideally suited to promote memory consolidation in distributed hippocampal–neocortical circuits. Further, since memory replay during SWRs has the capacity to recreate patterns of activity associated with past experience in hippocampal–neocortical circuits, it is also well suited to support memory retrieval. Thus, a common physiological mechanism, memory replay during SWRs, may underlie the consolidation and retrieval functions of the hippocampus.

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© Springer-Verlag Wien 2014

Authors and Affiliations

  1. 1.Department of Physiology, Center for Integrative NeuroscienceUniversity of CaliforniaSan FranciscoUSA

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