Long-term stability of cortical ensembles

  1. Jesús Pérez-Ortega  Is a corresponding author
  2. Tzitzitlini Alejandre-García
  3. Rafael Yuste  Is a corresponding author
  1. Columbia University, United States

Abstract

Neuronal ensembles, coactive groups of neurons found in spontaneous and evoked cortical activity, are causally related to memories and perception, but it still unknown how stable or flexible they are over time. We used two-photon multiplane calcium imaging to track over weeks the activity of the same pyramidal neurons in layer 2/3 of the visual cortex from awake mice and recorded their spontaneous and visually evoked responses. Less than half of the neurons were commonly active across any two imaging sessions. These 'common neurons' formed stable ensembles lasting weeks, but some ensembles were also transient and appeared only in one single session. Stable ensembles preserved ~68 % of their neurons up to 46 days, our longest imaged period, and these 'core' cells had stronger functional connectivity. Our results demonstrate that neuronal ensembles can last for weeks and could, in principle, serve as a substrate for long-lasting representation of perceptual states or memories.

Data availability

Data analyzed during this study are included in the manuscript and supporting files. Links to download the code developed in MATLAB are included in Methods. Data can also be found on Dryad, under the doi: 10.5061/dryad.cfxpnvx5m

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Jesús Pérez-Ortega

    Biological Sciences, Columbia University, New York, United States
    For correspondence
    jesus.perez@columbia.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8502-1692
  2. Tzitzitlini Alejandre-García

    Biological Sciences, Columbia University, New York, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Rafael Yuste

    Department of Biological Sciences, Columbia University, New York, United States
    For correspondence
    rmy5@columbia.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4206-497X

Funding

National Eye Institute (R01EY011787)

  • Rafael Yuste

National Institute of Mental Health (R01MH115900)

  • Rafael Yuste

Consejo Nacional de Ciencia y Tecnología (CVU365863)

  • Jesús Pérez-Ortega

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

Ethics

Animal experimentation: All experimental procedures were carried out in accordance with the US National Institutes of Health and Columbia University Institutional Animal Care and Use Committee (protocol AC-AAV3464).

Reviewing Editor

  1. Timothy O'Leary, University of Cambridge, United Kingdom

Publication history

  1. Preprint posted: October 28, 2020 (view preprint)
  2. Received: October 29, 2020
  3. Accepted: July 29, 2021
  4. Accepted Manuscript published: July 30, 2021 (version 1)
  5. Version of Record published: August 19, 2021 (version 2)

Copyright

© 2021, Pérez-Ortega 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. Jesús Pérez-Ortega
  2. Tzitzitlini Alejandre-García
  3. Rafael Yuste
(2021)
Long-term stability of cortical ensembles
eLife 10:e64449.
https://doi.org/10.7554/eLife.64449

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