title: Thalamus, brainstem and salience network connectivity changes during propofol-induced sedation and unconsciousness.
abstract: In this functional magnetic resonance imaging study, we examined the effect of mild propofol sedation and propofol-induced unconsciousness on resting state brain connectivity, using graph analysis based on independent component analysis and a classical seed-based analysis. Contrary to previous propofol research, which mainly emphasized the importance of connectivity in the default mode network (DMN) and external control network (ECN), we focused on the salience network, thalamus, and brainstem. The importance of these brain regions in brain arousal and organization merits a more detailed examination of their connectivity response to propofol. We found that the salience network disintegrated during propofol-induced unconsciousness. The thalamus decreased connectivity with the DMN, ECN, and salience network, while increasing connectivity with sensorimotor and auditory/insular cortices. Brainstem regions disconnected from the DMN with unconsciousness, while the pontine tegmental area increased connectivity with the insulae during mild sedation. These findings illustrate that loss of consciousness is associated with a wide variety of decreases and increases of both cortical and subcortical connectivity. It furthermore stresses the necessity of also examining resting state connectivity in networks representing arousal, not only those associated with awareness.
authors.affiliation: Coma Science Group, Cyclotron Research Center, University of Liège, Liège, Belgium. guldenmund@hotmail.com
authors.forename: Pieter
authors.initials: P
authors.lastname: Guldenmund
authors.forename: Athena
authors.initials: A
authors.lastname: Demertzi
authors.forename: Pierre
authors.initials: P
authors.lastname: Boveroux
authors.forename: Mélanie
authors.initials: M
authors.lastname: Boly
authors.forename: Audrey
authors.initials: A
authors.lastname: Vanhaudenhuyse
authors.forename: Marie-Aurélie
authors.initials: MA
authors.lastname: Bruno
authors.forename: Olivia
authors.initials: O
authors.lastname: Gosseries
authors.forename: Quentin
authors.initials: Q
authors.lastname: Noirhomme
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Brichant
authors.forename: Vincent
authors.initials: V
authors.lastname: Bonhomme
authors.forename: Steven
authors.initials: S
authors.lastname: Laureys
authors.forename: Andrea
authors.initials: A
authors.lastname: Soddu
mesh_terms: D018686:Anesthetics, Intravenous / Q000009:adverse effects*; D001931:Brain Mapping; D001933:Brain Stem / Q000098:blood supply / Q000187:drug effects*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D015201:Meta-Analysis as Topic; D009415:Nerve Net / Q000187:drug effects; D009434:Neural Pathways / Q000098:blood supply / Q000187:drug effects*; D010100:Oxygen / Q000097:blood; D015742:Propofol / Q000009:adverse effects*; D013788:Thalamus / Q000098:blood supply / Q000187:drug effects*; D014474:Unconsciousness / Q000139:chemically induced* / Q000473:pathology; D014851:Wakefulness / Q000502:physiology; D055815:Young Adult
chemical_list: D018686:Anesthetics, Intravenous; D010100:Oxygen; D015742:Propofol