Neural oscillations as a signature of efficient coding in the presence of synaptic delays

  1. Matthew Chalk  Is a corresponding author
  2. Boris Gutkin
  3. Sophie Denève
  1. Institute of Science and Technology Austria, Austria
  2. École Normale Supérieure, France

Abstract

Cortical networks exhibit 'global oscillations', where neural spikes are entrained to an underlying oscillatory rhythm, but where individual neurons fire irregularly. While the network dynamics underlying global oscillations are well characterised, their function is debated. Here, we show that such global oscillations are a direct consequence of optimal efficient coding in spiking networks with synaptic delays. To avoid firing unnecessary spikes, neurons must share information about the network state. Ideally, membrane potentials should be correlated and reflect a 'prediction error' while spikes themselves are uncorrelated and occur rarely. We show that the most efficient representation is achieved when: (i) spikes are entrained to a global Gamma rhythm (implying a consistent representation of the error); but (ii) few neurons fire on each cycle (implying high efficiency), while (iii) excitation and inhibition are tightly balanced. This suggests that cortical networks exhibiting such dynamics are tuned to achieve a maximally efficient population code.

Article and author information

Author details

  1. Matthew Chalk

    Institute of Science and Technology Austria, Klosterneuburg, Austria
    For correspondence
    matthewjchalk@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7782-4436
  2. Boris Gutkin

    École Normale Supérieure, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Sophie Denève

    École Normale Supérieure, Paris, France
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Peter Latham, University College London, United Kingdom

Publication history

  1. Received: December 17, 2015
  2. Accepted: July 5, 2016
  3. Accepted Manuscript published: July 7, 2016 (version 1)
  4. Version of Record published: July 25, 2016 (version 2)
  5. Version of Record updated: November 3, 2016 (version 3)

Copyright

© 2016, Chalk 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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  1. Matthew Chalk
  2. Boris Gutkin
  3. Sophie Denève
(2016)
Neural oscillations as a signature of efficient coding in the presence of synaptic delays
eLife 5:e13824.
https://doi.org/10.7554/eLife.13824

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