title: Propofol induction reduces the capacity for neural information integration: implications for the mechanism of consciousness and general anesthesia.
abstract: The cognitive unbinding paradigm suggests that the synthesis of neural information is attenuated by general anesthesia. Here, we analyzed the functional organization of brain activities in the conscious and anesthetized states, based on functional segregation and integration. Electroencephalography (EEG) recordings were obtained from 14 subjects undergoing induction of general anesthesia with propofol. We quantified changes in mean information integration capacity in each band of the EEG. After induction with propofol, mean information integration capacity was reduced most prominently in the gamma band of the EEG (p=.0001). Furthermore, we demonstrate that loss of consciousness is reflected by the breakdown of the spatiotemporal organization of gamma waves. We conclude that induction of general anesthesia with propofol reduces the capacity for information integration in the brain. These data directly support the information integration theory of consciousness and the cognitive unbinding paradigm of general anesthesia.
authors.affiliation: Department of Anesthesiology, University of Michigan Medical School, Ann Arbor, MI 48109-0048, USA.
authors.forename: UnCheol
authors.initials: U
authors.lastname: Lee
authors.forename: George A
authors.initials: GA
authors.lastname: Mashour
authors.forename: Seunghwan
authors.initials: S
authors.lastname: Kim
authors.forename: Gyu-Jeong
authors.initials: GJ
authors.lastname: Noh
authors.forename: Byung-Moon
authors.initials: BM
authors.lastname: Choi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000768:Anesthesia, General / Q000379:methods*; D018686:Anesthetics, Intravenous / Q000494:pharmacology*; D003243:Consciousness / Q000187:drug effects*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000187:drug effects*; D009431:Neural Conduction / Q000187:drug effects*; D009434:Neural Pathways / Q000187:drug effects*; D010468:Perceptual Disorders / Q000139:chemically induced; D015742:Propofol / Q000494:pharmacology*; D013028:Space Perception / Q000187:drug effects; D013998:Time Perception / Q000187:drug effects; D055815:Young Adult
chemical_list: D018686:Anesthetics, Intravenous; D015742:Propofol