Can sleep protect memories from catastrophic forgetting?

  1. Oscar C González
  2. Yury Sokolov
  3. Giri P Krishnan
  4. Jean Erik Delanois
  5. Maxim Bazhenov  Is a corresponding author
  1. University of California San Diego, United States

Abstract

Continual learning remains to be an unsolved problem in artificial neural networks. The brain has evolved mechanisms to prevent catastrophic forgetting of old knowledge during new training. Building upon data suggesting importance of sleep in learning and memory, we tested a hypothesis that sleep protects old memories from forgetting. In the thalamocortical model, training a new memory interfered with previously learned old memories leading to degradation and forgetting of the old memory traces. Simulating sleep immediately after new learning reversed the damage and enhanced all memories. We found that when a new memory competed for previously allocated neuronal/synaptic resources, sleep replay changed the synaptic footprint of the old memory to allow overlapping neuronal populations to store multiple memories. Our study predicts that memory storage is dynamic, and sleep enables continual learning by combining consolidation of new memory traces with reconsolidation of old memory traces to minimize interference.

Data availability

Computational models were used exclusively in this study. The model is fully described in the Methods section and code has been deposited to https://github.com/o2gonzalez/sequenceLearningSleepCode.

Article and author information

Author details

  1. Oscar C González

    Medicine, University of California San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1302-1911
  2. Yury Sokolov

    Medicine, University of California San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Giri P Krishnan

    Medicine, University of California San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3931-7633
  4. Jean Erik Delanois

    Medicine, University of California San Diego, La Jolla, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Maxim Bazhenov

    Medicine, University of California San Diego, La Jolla, United States
    For correspondence
    mbazhenov@ucsd.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1936-0570

Funding

Defense Advanced Research Projects Agency (HR0011-18-2-0021)

  • Maxim Bazhenov

Office of Naval Research (MURI: N00014-16-1-2829)

  • Maxim Bazhenov

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Mark CW van Rossum, University of Nottingham, United Kingdom

Version history

  1. Received: January 19, 2020
  2. Accepted: July 19, 2020
  3. Accepted Manuscript published: August 4, 2020 (version 1)
  4. Version of Record published: August 20, 2020 (version 2)
  5. Version of Record updated: August 26, 2020 (version 3)

Copyright

© 2020, González 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. Oscar C González
  2. Yury Sokolov
  3. Giri P Krishnan
  4. Jean Erik Delanois
  5. Maxim Bazhenov
(2020)
Can sleep protect memories from catastrophic forgetting?
eLife 9:e51005.
https://doi.org/10.7554/eLife.51005

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