Disruption of thalamic functional connectivity is a neural correlate of dexmedetomidine-induced unconsciousness

Understanding the neural basis of consciousness is fundamental to neuroscience research. Disruptions in cortico-cortical connectivity have been suggested as a primary mechanism of unconsciousness. By using a novel combination of positron emission tomography and functional magnetic resonance imaging,...

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Bibliographic Details
Main Authors: Akeju, Oluwaseun, Catana, Ciprian, Vazquez, Rafael, Rhee, James, Contreras Ramirez, Violeta, Izquierdo-Garcia, David, Arabasz, Grae, Hsu, Shirley, Habeeb, Kathleen, Napadow, Vitaly, Chonde, Daniel B., Loggia, Marco L., Hooker, Jacob M., Purdon, Patrick Lee, Pavone, Kara J., Brown, Emery Neal
Other Authors: Massachusetts Institute of Technology. Institute for Medical Engineering & Science
Format: Article
Language:en_US
Published: eLife Sciences Publications, Ltd. 2015
Online Access:http://hdl.handle.net/1721.1/92614
https://orcid.org/0000-0001-7067-2628
https://orcid.org/0000-0001-5651-5060
https://orcid.org/0000-0003-2668-7819
Description
Summary:Understanding the neural basis of consciousness is fundamental to neuroscience research. Disruptions in cortico-cortical connectivity have been suggested as a primary mechanism of unconsciousness. By using a novel combination of positron emission tomography and functional magnetic resonance imaging, we studied anesthesia-induced unconsciousness and recovery using the α[subscript 2]-agonist dexmedetomidine. During unconsciousness, cerebral metabolic rate of glucose and cerebral blood flow were preferentially decreased in the thalamus, the Default Mode Network (DMN), and the bilateral Frontoparietal Networks (FPNs). Cortico-cortical functional connectivity within the DMN and FPNs was preserved. However, DMN thalamo-cortical functional connectivity was disrupted. Recovery from this state was associated with sustained reduction in cerebral blood flow and restored DMN thalamo-cortical functional connectivity. We report that loss of thalamo-cortical functional connectivity is sufficient to produce unconsciousness.