title: Brain networks affected by synchronized sleep visualized by positron emission tomography.
abstract: Nineteen lightly sleep-deprived healthy volunteers were examined with H2(15)O and positron emission tomography (PET). Scanning was performed during wakefulness and after the subjects had fallen asleep. Sleep stage was graded retrospectively from electroencephalogram (EEG) recordings, and scans were divided into two groups: wakefulness or synchronized sleep. Global flow was quantified, revealing no difference between sleep and wakefulness. A pixel-by-pixel-blocked one-way analysis of variance (ANOVA) was performed after correcting for differences in anatomy and global flow. The sum of squares of the z-score distribution showed a highly significant (P < 0.00001) omnibus difference between sleep and wakefulness. The z-score images indicated decreased flow in the thalamus and the frontal and parietal association cortices and increased flow in the cerebellum during sleep. A principal component (PC) analysis was performed on data after correction for global flow and block effects, and a multivariate analysis of variance (MANOVA) on all PC scores revealed significant (P = 0.00004) differences between sleep and wakefulness. Principal component's 2 and 5 correlated to sleep and revealed distinct networks consisting of PC 2, cerebellum and frontal and parietal association cortices, and PC 5, thalamus.
authors.affiliation: Uppsala University PET-Centre, Subfemtomole Biorecognition Project, Sweden.
authors.forename: J L
authors.initials: JL
authors.lastname: Andersson
authors.forename: H
authors.initials: H
authors.lastname: Onoe
authors.forename: J
authors.initials: J
authors.lastname: Hetta
authors.forename: K
authors.initials: K
authors.lastname: Lidström
authors.forename: S
authors.initials: S
authors.lastname: Valind
authors.forename: A
authors.initials: A
authors.lastname: Lilja
authors.forename: A
authors.initials: A
authors.lastname: Sundin
authors.forename: K J
authors.initials: KJ
authors.lastname: Fasth
authors.forename: G
authors.initials: G
authors.lastname: Westerberg
authors.forename: J E
authors.initials: JE
authors.lastname: Broman
authors.forename: Y
authors.initials: Y
authors.lastname: Watanabe
authors.forename: B
authors.initials: B
authors.lastname: Långström
mesh_terms: D000704:Analysis of Variance; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology*; D001931:Brain Mapping; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004569:Electroencephalography; D006801:Humans; D009415:Nerve Net / Q000502:physiology*; D010104:Oxygen Radioisotopes / Q000493:pharmacokinetics; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012044:Regression Analysis; D012894:Sleep Stages / Q000502:physiology*; D014055:Tomography, Emission-Computed; D014851:Wakefulness / Q000502:physiology
chemical_list: D010104:Oxygen Radioisotopes; D019275:Radiopharmaceuticals