A unified dynamic model for learning, replay, and sharp-wave/ripples

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Sven Jahnke - , Max Planck Institute for Dynamics and Self-Organization, University of Göttingen (Author)
  • Marc Timme - , Max Planck Institute for Dynamics and Self-Organization, University of Göttingen, Bernstein Center Computational Neuroscience Berlin (Author)
  • Raoul Martin Memmesheimer - , Columbia University, Radboud University Nijmegen (Author)

Abstract

Hippocampal activity is fundamental for episodic memory formation and consolidation. During phases of rest and sleep, it exhibits sharp-wave/ripple (SPW/R) complexes, which are short episodes of increased activity with superimposed high-frequency oscillations. Simultaneously, spike sequences reflecting previous behavior, such as traversed trajectories in space, are replayed. Whereas these phenomena are thought to be crucial for the formation and consolidation of episodic memory, their neurophysiological mechanisms are not well understood. Here we present a unified model showing how experience may be stored and thereafter replayed in association with SPW/Rs. We propose that replay and SPW/Rs are tightly interconnected as they mutually generate and support each other. The underlying mechanism is based on the nonlinear dendritic computation attributable to dendritic sodium spikes that have been prominently found in the hippocampal regions CA1 and CA3, where SPW/Rs and replay are also generated. Besides assigning SPW/Rs a crucial role for replay and thus memory processing, the proposed mechanism also explains their characteristic features, such as the oscillation frequency and the overall wave form. The results shed a new light on the dynamical aspects of hippocampal circuit learning.

Details

Original languageEnglish
Pages (from-to)16236-16258
Number of pages23
JournalJournal of Neuroscience
Volume35
Issue number49
Publication statusPublished - 9 Dec 2015
Peer-reviewedYes
Externally publishedYes

External IDs

PubMed 26658873
ORCID /0000-0002-5956-3137/work/142242461

Keywords

ASJC Scopus subject areas

Keywords

  • Dendritic spikes, Learning, Memory, Network, Replay, Sharp-wave/ripples

Library keywords