title: Modeling Neurocognitive Decline and Recovery During Repeated Cycles of Extended Sleep and Chronic Sleep Deficiency.
abstract: Intraindividual night-to-night sleep duration is often insufficient and variable. Here we report the effects of such chronic variable sleep deficiency on neurobehavioral performance and the ability of state-of-the-art models to predict these changes.
  
  
  
  Eight healthy males (mean age ± SD: 23.9 ± 2.4 years) studied at our inpatient intensive physiologic monitoring unit completed an 11-day protocol with a baseline 10-hour sleep opportunity and three cycles of two 3-hour time-in-bed (TIB) and one 10-hour TIB sleep opportunities. Participants received one of three polychromatic white light interventions (200 lux 4100K, 200 or 400 lux 17000K) for 3.5 hours on the morning following the second 3-hour TIB opportunity each cycle. Neurocognitive performance was assessed using the psychomotor vigilance test (PVT) administered every 1-2 hours. PVT data were compared to predictions of five group-average mathematical models that incorporate chronic sleep loss functions.
  
  
  
  While PVT performance deteriorated cumulatively following each cycle of two 3-hour sleep opportunities, and improved following each 10-hour sleep opportunity, performance declined cumulatively throughout the protocol at a more accelerated rate than predicted by state-of-the-art group-average mathematical models. Subjective sleepiness did not reflect performance. The light interventions had minimal effect.
  
  
  
  Despite apparent recovery following each extended sleep opportunity, residual performance impairment remained and deteriorated rapidly when rechallenged with subsequent sleep loss. None of the group-average models were capable of predicting both the build-up in impairment and recovery profile of performance observed at the group or individual level, raising concerns regarding their use in real-world settings to predict performance and improve safety.
authors.affiliation: Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA.|Department of Medicine, Division of Sleep Medicine, Harvard Medical School, Boston, MA.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: St Hilaire
authors.affiliation: Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA.|Department of Medicine, Division of Sleep Medicine, Harvard Medical School, Boston, MA.
authors.forename: Melanie
authors.initials: M
authors.lastname: Rüger
authors.affiliation: Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA.|Department of Medicine, Division of Sleep Medicine, Harvard Medical School, Boston, MA.|Department of Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom.
authors.forename: Federico
authors.initials: F
authors.lastname: Fratelli
authors.affiliation: Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA.|Department of Medicine, Division of Sleep Medicine, Harvard Medical School, Boston, MA.
authors.forename: Joseph T
authors.initials: JT
authors.lastname: Hull
authors.affiliation: Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA.|Department of Medicine, Division of Sleep Medicine, Harvard Medical School, Boston, MA.
authors.forename: Andrew J K
authors.initials: AJ
authors.lastname: Phillips
authors.affiliation: Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA.|Department of Medicine, Division of Sleep Medicine, Harvard Medical School, Boston, MA.
authors.forename: Steven W
authors.initials: SW
authors.lastname: Lockley
mesh_terms: D002908:Chronic Disease / Q000523:psychology; D003071:Cognition / Q000502:physiology* / Q000528:radiation effects; D065386:Historically Controlled Study; D006801:Humans; D008027:Light; D008297:Male; D012890:Sleep / Q000502:physiology* / Q000528:radiation effects; D012892:Sleep Deprivation / Q000503:physiopathology* / Q000523:psychology*; D007319:Sleep Initiation and Maintenance Disorders / Q000503:physiopathology / Q000523:psychology; D012894:Sleep Stages / Q000502:physiology / Q000528:radiation effects; D013997:Time Factors; D014851:Wakefulness / Q000502:physiology / Q000528:radiation effects; D055815:Young Adult
keywords: chronic variable sleep deficiency; neurobehavioral performance; physiological adaptation; recovery of function.; recovery sleep; subjective sleepiness