1. Neuroscience
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Optimal compensation for neuron loss

  1. David TG Barrett
  2. Sophie Denève
  3. Christian K Machens  Is a corresponding author
  1. University of Cambridge, United Kingdom
  2. École Normale Supérieure, France
  3. Champalimaud Centre for the Unknown, Portugal
Research Article
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Cite this article as: eLife 2016;5:e12454 doi: 10.7554/eLife.12454

Abstract

The brain has an impressive ability to withstand neural damage. Diseases that kill neurons can go unnoticed for years, and incomplete brain lesions or silencing of neurons often fail to produce any behavioral effect. How does the brain compensate for such damage, and what are the limits of this compensation? We propose that neural circuits immediately compensate for neuron loss, thereby preserving their function as much as possible. We show that this compensation can explain changes in tuning curves induced by neuron silencing across a variety of systems, including the primary visual cortex. We find that compensatory mechanisms can be implemented through the dynamics of networks with a tight balance of excitation and inhibition, without requiring synaptic plasticity. The limits of this compensatory mechanism are reached when excitation and inhibition become unbalanced, thereby demarcating a recovery boundary, where signal representation fails and where diseases may become symptomatic.

Article and author information

Author details

  1. David TG Barrett

    Department of Engineering, University of Cambridge, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Sophie Denève

    Laboratoire de Neurosciences Cognitives, École Normale Supérieure, Paris, France
    Competing interests
    The authors declare that no competing interests exist.
  3. Christian K Machens

    Champalimaud Centre for the Unknown, Lisbon, Portugal
    For correspondence
    christian.machens@neuro.fchampalimaud.org
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1717-1562

Funding

Deutsche Forschungsgemeinschaft (Emmy-Noether)

  • Christian K Machens

Agence Nationale de Recherche (Chaire d'Excellence)

  • Christian K Machens

James McDonnell Foundation

  • Christian K Machens

European Research Council (ERC FP7-PREDSPIKE)

  • Christian K Machens

European Research Council (BIND MECT-CT-20095-024831)

  • Christian K Machens

European Research Council (BACS 796 FP6-IST-027140)

  • Christian K Machens

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

Reviewing Editor

  1. Frances K Skinner, University Health Network, Canada

Publication history

  1. Received: October 20, 2015
  2. Accepted: December 8, 2016
  3. Accepted Manuscript published: December 9, 2016 (version 1)
  4. Version of Record published: January 31, 2017 (version 2)

Copyright

© 2016, Barrett 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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