title: Cerebral perfusion differences between drowsy and nondrowsy individuals after acute sleep restriction.
abstract: OBJECTIVE
  To investigate changes in resting cerebral blood flow (CBF) after acute sleep restriction. To investigate the extent to which changes in CBF after sleep restriction are related to drowsiness as manifested in eye-video.
  
  
  METHODS
  Participants were scanned for 5 min using arterial spin labeling (ASL) perfusion imaging after both sleep-restricted and rested nights. Participants were rated for visual signs of drowsiness in the eye-video recorded during the scan.
  
  
  METHODS
  Lying supine in a 3-Tesla magnetic resonance imaging scanner.
  
  
  METHODS
  Twenty healthy adults (age 20-37 yr) with no history of neurologic, psychiatric, or sleep disorder, and with usual time in bed of 7.0-8.5 h.
  
  
  METHODS
  In the night before the sleep-restricted session, participants were restricted to 4 h time in bed.
  
  
  RESULTS
  There was an overall reduction in CBF in the right-lateralized fronto-parietal attentional network after acute sleep restriction, although this was largely driven by participants who showed strong signs of drowsiness in the eye-video after sleep restriction. Change in CBF correlated with change in drowsiness in the basal forebrain-cingulate regions. In particular, there was a pronounced increase in CBF in the basal forebrain and anterior and posterior cingulate cortex of participants who remained alert after sleep restriction.
  
  
  CONCLUSIONS
  The pattern of cerebral activity after acute sleep restriction is highly dependent on level of drowsiness. Nondrowsy individuals are able to increase activity in the arousal-promoting brain regions and maintain activity in attentional regions. In contrast, drowsy individuals are unable to maintain arousal and show decreased activity in both arousal-promoting and attentional regions.
authors.affiliation: New Zealand Brain Research Institute; Medicine, University of Otago, Christchurch, New Zealand. govinda.poudel@vanderveer.org.nz
authors.forename: Govinda R
authors.initials: GR
authors.lastname: Poudel
authors.forename: Carrie R H
authors.initials: CR
authors.lastname: Innes
authors.forename: Richard D
authors.initials: RD
authors.lastname: Jones
mesh_terms: D000328:Adult; D001143:Arousal / Q000502:physiology; D001158:Arteries; D001288:Attention / Q000502:physiology*; D001921:Brain / Q000098:blood supply* / Q000502:physiology; D002560:Cerebrovascular Circulation; D005260:Female; D006179:Gyrus Cinguli / Q000098:blood supply / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D055420:Perfusion Imaging; D012892:Sleep Deprivation / Q000503:physiopathology*; D012894:Sleep Stages / Q000502:physiology*; D013113:Spin Labels; D055815:Young Adult
chemical_list: D013113:Spin Labels