Editorial Views  |   April 2019
General Anesthesia and the Cortex: Communication Breakdown?
Author Notes
  • From the Center for Consciousness Science, Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan.
  • Corresponding article on page 560.
    Corresponding article on page 560.×
  • Accepted for publication January 12, 2019.
    Accepted for publication January 12, 2019.×
  • Address correspondence to Dr. Mashour: gmashour@umich.edu
Article Information
Editorial Views / Central and Peripheral Nervous Systems / Pharmacology
Editorial Views   |   April 2019
General Anesthesia and the Cortex: Communication Breakdown?
Anesthesiology 4 2019, Vol.130, 526-527. doi:10.1097/ALN.0000000000002636
Anesthesiology 4 2019, Vol.130, 526-527. doi:10.1097/ALN.0000000000002636
There is a growing body of evidence to suggest that depression or functional disconnection of frontal–parietal networks occurs during general anesthesia.1  If fully confirmed, this would be an important advance for anesthesiology because it could help us (1) understand how our anesthetic drugs act to cause unconsciousness, and (2) monitor the effects of our anesthetic drugs in the clinical setting. The hypothesis that general anesthesia is a kind of “communication breakdown” between the front and back of the brain could be a parsimonious approach that informs both mechanistic understanding and clinical care. However, most studies of the frontal–parietal network during anesthesia have been conducted with functional magnetic resonance imaging (with slower time scales) or electroencephalography (with fuzzy spatial relationships). How do these findings hold up when assessing a neurophysiologic time scale in well-defined circuits across the frontal–parietal network? In this issue of Anesthesiology, Ma et al.2  report the study of a specific neurophysiologic relationship across the oculomotor circuit—a well-defined and structurally connected tract from the frontal cortex to parietal cortex—on the surface of the primate brain. They find, contrary to what would be predicted based on past studies in humans and rodents, that propofol increases long-range functional coupling of neural activity across this frontal–parietal circuit. Their work prompts the question of whether general anesthesia really is a state of communication breakdown across the cortex and what the implications are for clinical monitoring.