Recovery of consciousness and cognition after general anesthesia in humans
- University of Michigan, United States
- Washington University, United States
- University of Pennsylvania, United States
- McGill University, Canada
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
Andrew R McKinstry-Wu
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
- Redmond G O'Connell, Trinity College Dublin, Ireland
Version history
- Received: June 1, 2020
- Accepted: May 6, 2021
- Accepted Manuscript published: May 10, 2021 (version 1)
- 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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Recovery of consciousness and cognition after general anesthesia in humans
eLife 10:e59525.
https://doi.org/10.7554/eLife.59525
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