title: Tired and misconnected: A breakdown of brain modularity following sleep deprivation.
abstract: Sleep deprivation (SD) critically affects a range of cognitive and affective functions, typically assessed during task performance. Whether such impairments stem from changes to the brain's intrinsic functional connectivity remain largely unknown. To examine this hypothesis, we applied graph theoretical analysis on resting-state fMRI data derived from 18 healthy participants, acquired during both sleep-rested and sleep-deprived states. We hypothesized that parameters indicative of graph connectivity, such as modularity, will be impaired by sleep deprivation and that these changes will correlate with behavioral outcomes elicited by sleep loss. As expected, our findings point to a profound reduction in network modularity without sleep, evident in the limbic, default-mode, salience and executive modules. These changes were further associated with behavioral impairments elicited by SD: a decrease in salience module density was associated with worse task performance, an increase in limbic module density was predictive of stronger amygdala activation in a subsequent emotional-distraction task and a shift in frontal hub lateralization (from left to right) was associated with increased negative mood. Altogether, these results portray a loss of functional segregation within the brain and a shift towards a more random-like network without sleep, already detected in the spontaneous activity of the sleep-deprived brain. Hum Brain Mapp 38:3300-3314, 2017. © 2017 Wiley Periodicals, Inc.
authors.affiliation: Functional Brain Center, Wohl Institute for Advanced Imaging Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel.|Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Eti
authors.identifier: 0000-0002-3862-8288
authors.initials: E
authors.lastname: Ben Simon
authors.affiliation: Functional Brain Center, Wohl Institute for Advanced Imaging Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel.|Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Adi
authors.initials: A
authors.lastname: Maron-Katz
authors.affiliation: Department of Physics, Bar-Ilan University, Ramat Gan, Israel.
authors.forename: Nir
authors.initials: N
authors.lastname: Lahav
authors.affiliation: Blavatnik School of Computer Science, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Ron
authors.initials: R
authors.lastname: Shamir
authors.affiliation: Functional Brain Center, Wohl Institute for Advanced Imaging Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel.|Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.|School of Psychological Sciences, Tel Aviv University, Tel-Aviv, Israel.|Sagol school of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Talma
authors.initials: T
authors.lastname: Hendler
mesh_terms: D000328:Adult; D000339:Affect; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology*; D001931:Brain Mapping; D003072:Cognition Disorders / Q000209:etiology; D004644:Emotions; D056344:Executive Function / Q000502:physiology; D005221:Fatigue / Q000209:etiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008959:Models, Neurological; D009434:Neural Pathways / Q000000981:diagnostic imaging / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D010775:Photic Stimulation; D012892:Sleep Deprivation / Q000150:complications* / Q000473:pathology*; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: amygdala; fMRI; functional connectivity; graph theory; modularity; mood; sleep deprivation