title: Network-dependent modulation of brain activity during sleep.
abstract: Brain activity dynamically changes even during sleep. A line of neuroimaging studies has reported changes in functional connectivity and regional activity across different sleep stages such as slow-wave sleep (SWS) and rapid-eye-movement (REM) sleep. However, it remains unclear whether and how the large-scale network activity of human brains changes within a given sleep stage. Here, we investigated modulation of network activity within sleep stages by applying the pairwise maximum entropy model to brain activity obtained by functional magnetic resonance imaging from sleeping healthy subjects. We found that the brain activity of individual brain regions and functional interactions between pairs of regions significantly increased in the default-mode network during SWS and decreased during REM sleep. In contrast, the network activity of the fronto-parietal and sensory-motor networks showed the opposite pattern. Furthermore, in the three networks, the amount of the activity changes throughout REM sleep was negatively correlated with that throughout SWS. The present findings suggest that the brain activity is dynamically modulated even in a sleep stage and that the pattern of modulation depends on the type of the large-scale brain networks.
authors.affiliation: Department of Physiology, The University of Tokyo, School of Medicine, Tokyo, 113-0033, Japan; Institute of Cognitive Neuroscience, University College London, London, WC1N 3AR, UK. Electronic address: takamitsu.watanabe@ucl.ac.uk.
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Advanced ICT Research Institute, National Institute of Information and Communications Technology, Hyogo, 651-2492, Japan.
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Kan
authors.affiliation: Advanced ICT Research Institute, National Institute of Information and Communications Technology, Hyogo, 651-2492, Japan.
authors.forename: Takahiko
authors.initials: T
authors.lastname: Koike
authors.affiliation: Advanced ICT Research Institute, National Institute of Information and Communications Technology, Hyogo, 651-2492, Japan.
authors.forename: Masaya
authors.initials: M
authors.lastname: Misaki
authors.affiliation: Department of Physiology, The University of Tokyo, School of Medicine, Tokyo, 113-0033, Japan.
authors.forename: Seiki
authors.initials: S
authors.lastname: Konishi
authors.affiliation: Advanced ICT Research Institute, National Institute of Information and Communications Technology, Hyogo, 651-2492, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Miyauchi
authors.affiliation: Department of Physiology, The University of Tokyo, School of Medicine, Tokyo, 113-0033, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Miyahsita
authors.affiliation: Department of Mathematical Informatics, The University of Tokyo, Tokyo, 113-8656, Japan. Electronic address: masuda@mist.i.u-tokyo.ac.jp.
authors.forename: Naoki
authors.initials: N
authors.lastname: Masuda
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D012894:Sleep Stages / Q000502:physiology*; D055815:Young Adult