Abstract

Understanding how the brain recovers from unconsciousness can inform neurobiological theories of consciousness and guide clinical investigation. To address this question, we conducted a multicenter study of 60 healthy humans, half of whom received general anesthesia for three hours and half of whom served as awake controls. We administered a battery of neurocognitive tests and recorded electroencephalography to assess cortical dynamics. We hypothesized that recovery of consciousness and cognition is an extended process, with differential recovery of cognitive functions that would commence with return of responsiveness and end with return of executive function, mediated by prefrontal cortex. We found that, just prior to the recovery of consciousness, frontal-parietal dynamics returned to baseline. Consistent with our hypothesis, cognitive reconstitution after anesthesia evolved over time. Contrary to our hypothesis, executive function returned first. Early engagement of prefrontal cortex in recovery of consciousness and cognition is consistent with global neuronal workspace theory.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files. Source data have been provided for Figures 2-5.

Article and author information

Author details

  1. George A Mashour

    Anesthesiology; Neuroscience, University of Michigan, Ann Arbor, United States
    For correspondence
    gmashour@umich.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5457-5932
  2. Ben JA Palanca

    Anesthesiology, Washington University, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Mathias Basner

    Psychiatry, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Duan Li

    Anesthesiology, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Wei Wang

    Statistics, Washington University, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Stephanie Blain-Moraes

    Occupational Therapy; Biomedical Engineering, McGill University, Montreal, Canada
    Competing interests
    The authors declare that no competing interests exist.
  7. Nan Lin

    Statistics, Washington University, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Kaitlyn Maier

    Anesthesiology, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Maxwell Muench

    Anesthesiology, Washington University, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Vijay Tarnal

    Anesthesiology, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  11. Giancarlo Vanini

    Anesthesiology; Neuroscience, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  12. E Andrew Ochroch

    Anesthesiology, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
  13. Rosemary Hogg

    Anesthesiology, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
  14. Marlon Schwartz

    Anesthesiology, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
  15. Hannah Maybrier

    Anesthesiology, Washington University, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  16. Randall Hardie

    Anesthesiology, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
  17. Ellen Janke

    Anesthesiology, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  18. Goodarz Golmirzaie

    Anesthesiology, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  19. Paul Picton

    Anesthesiology, University of Michigan, Ann Arbor, United States
    Competing interests
    The authors declare that no competing interests exist.
  20. Andrew R McKinstry-Wu

    Anesthesiology, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7078-4603
  21. Michael S Avidan

    Anesthesiology, Washington University, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  22. Max B Kelz

    Bioengineering, Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2803-6078

Funding

James S. McDonnell Foundation (Understanding Human Cognition)

  • George A Mashour

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

Ethics

Human subjects: The study received ethics committee approval from the University of Michigan, Washington University, and the University of Pennsylvania; written informed consent was obtained after careful discussion with each participant.

Reviewing Editor

  1. Redmond G O'Connell, Trinity College Dublin, Ireland

Version history

  1. Received: June 1, 2020
  2. Accepted: May 6, 2021
  3. Accepted Manuscript published: May 10, 2021 (version 1)
  4. Version of Record published: May 28, 2021 (version 2)

Copyright

© 2021, Mashour 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. George A Mashour
  2. Ben JA Palanca
  3. Mathias Basner
  4. Duan Li
  5. Wei Wang
  6. Stephanie Blain-Moraes
  7. Nan Lin
  8. Kaitlyn Maier
  9. Maxwell Muench
  10. Vijay Tarnal
  11. Giancarlo Vanini
  12. E Andrew Ochroch
  13. Rosemary Hogg
  14. Marlon Schwartz
  15. Hannah Maybrier
  16. Randall Hardie
  17. Ellen Janke
  18. Goodarz Golmirzaie
  19. Paul Picton
  20. Andrew R McKinstry-Wu
  21. Michael S Avidan
  22. Max B Kelz
(2021)
Recovery of consciousness and cognition after general anesthesia in humans
eLife 10:e59525.
https://doi.org/10.7554/eLife.59525

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