title: Rhythmic alternating patterns of brain activity distinguish rapid eye movement sleep from other states of consciousness.
abstract: Rapid eye movement (REM) sleep constitutes a distinct "third state" of consciousness, during which levels of brain activity are commensurate with wakefulness, but conscious awareness is radically transformed. To characterize the temporal and spatial features of this paradoxical state, we examined functional interactions between brain regions using fMRI resting-state connectivity methods. Supporting the view that the functional integrity of the default mode network (DMN) reflects "level of consciousness," we observed functional uncoupling of the DMN during deep sleep and recoupling during REM sleep (similar to wakefulness). However, unlike either deep sleep or wakefulness, REM was characterized by a more widespread, temporally dynamic interaction between two major brain systems: unimodal sensorimotor areas and the higher-order association cortices (including the DMN), which normally regulate their activity. During REM, these two systems become anticorrelated and fluctuate rhythmically, in reciprocally alternating multisecond epochs with a frequency ranging from 0.1 to 0.01 Hz. This unique spatiotemporal pattern suggests a model for REM sleep that may be consistent with its role in dream formation and memory consolidation.
authors.affiliation: Language Section, Voice, Speech, and Language Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA. chowh@nidcd.nih.gov
authors.forename: Ho Ming
authors.initials: HM
authors.lastname: Chow
authors.forename: Silvina G
authors.initials: SG
authors.lastname: Horovitz
authors.forename: Walter S
authors.initials: WS
authors.lastname: Carr
authors.forename: Dante
authors.initials: D
authors.lastname: Picchioni
authors.forename: Nate
authors.initials: N
authors.lastname: Coddington
authors.forename: Masaki
authors.initials: M
authors.lastname: Fukunaga
authors.forename: Yisheng
authors.initials: Y
authors.lastname: Xu
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Balkin
authors.forename: Jeff H
authors.initials: JH
authors.lastname: Duyn
authors.forename: Allen R
authors.initials: AR
authors.lastname: Braun
mesh_terms: D000328:Adult; D063132:Connectome / Q000379:methods*; D003243:Consciousness / Q000502:physiology*; D004325:Dreams / Q000502:physiology; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D010296:Parietal Lobe / Q000502:physiology; D017397:Prefrontal Cortex / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D012895:Sleep, REM / Q000502:physiology*; D013788:Thalamus / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology; D055815:Young Adult
keywords: EEG; brain dynamics; fMRI; slow-wave sleep; thalamus