Theta-modulation drives the emergence of connectivity patterns underlying replay in a network model of place cells
Abstract
Place cells of the rodent hippocampus fire action potentials when the animal traverses a particular spatial location in any environment. Therefore for any given trajectory one observes a repeatable sequence of place cell activations. When the animal is quiescent or sleeping, one can observe similar sequences of activation known as replay, which underlie the process of memory consolidation. However, it remains unclear how replay is generated. Here we show how a temporally asymmetric plasticity rule during spatial exploration gives rise to spontaneous replay in a model network by shaping the recurrent connectivity to reflect the topology of the learned environment. Crucially, the rate of this encoding is strongly modulated by ongoing rhythms. Oscillations in the theta range optimize learning by generating repeated pre-post pairings on a time-scale commensurate with the window for plasticity, while lower and higher frequencies generate learning rates which are lower by orders of magnitude.
Data availability
All electrophysiological data has been uploaded to the Dryad website. The DOI is doi:10.5061/dryad.n9c1rb0
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Data from: Theta-modulation drives the emergence of connectivity patterns underlying replay in a network model of place cellsAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
Article and author information
Author details
Funding
Ministerio de Economía y Competitividad (BFU-2012-33413)
- Alex Roxin
Ministerio de Economía y Competitividad (MTM-2015-71509)
- Alex Roxin
Generalitat de Catalunya (CERCA program)
- Alex Roxin
Howard Hughes Medical Institute
- Yingxue Wang
Max-Planck-Gesellschaft
- Yingxue Wang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Theodoni et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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