title: The Effects of Sleep Continuity Disruption on Positive Mood and Sleep Architecture in Healthy Adults.
abstract: OBJECTIVE
  The purpose of this study was to test an experimental model of the effects of sleep continuity disturbance on sleep architecture and positive mood in order to better understand the mechanisms linking insomnia and depression.
  
  
  METHODS
  Participants were randomized to receive 3 consecutive nights of sleep continuity disruption via forced nocturnal awakenings (FA, n = 21), or one of two control conditions: restricted sleep opportunity (RSO, n = 17) or uninterrupted sleep (US, n = 24).
  
  
  METHODS
  The study was set in an inpatient clinical research suite.
  
  
  METHODS
  Healthy, good-sleeping men and women were included.
  
  
  RESULTS
  Polysomnography was used to measure sleep architecture, and mood was assessed via self-report each day. Compared to restricted sleep opportunity controls, forced awakenings subjects had significantly less slow wave sleep (P < 0.05) after the first night of sleep deprivation, and significantly lower positive mood (P < 0.05) after the second night of sleep deprivation. The differential change in slow wave sleep statistically mediated the observed group differences in positive mood (P = 0.002).
  
  
  CONCLUSIONS
  To our knowledge, this is the first human experimental study to demonstrate that, despite comparable reductions in total sleep time, partial sleep loss from sleep continuity disruption is more detrimental to positive mood than partial sleep loss from delaying bedtime, even when controlling for concomitant increases in negative mood. With these findings, we provide temporal evidence in support of a putative biologic mechanism (slow wave sleep deficit) that could help explain the strong comorbidity between insomnia and depression.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD.
authors.forename: Patrick H
authors.initials: PH
authors.lastname: Finan
authors.affiliation: Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research.
authors.forename: Phillip J
authors.initials: PJ
authors.lastname: Quartana
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Smith
mesh_terms: D000328:Adult; D000339:Affect; D015897:Comorbidity; D003863:Depression / Q000453:epidemiology; D005260:Female; D064368:Healthy Volunteers / Q000523:psychology*; D006801:Humans; D008297:Male; D017286:Polysomnography; D057566:Self Report; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000503:physiopathology* / Q000523:psychology*; D007319:Sleep Initiation and Maintenance Disorders / Q000453:epidemiology; D013997:Time Factors; D014851:Wakefulness; D055815:Young Adult
keywords: insomnia; positive mood; sleep continuity disruption; sleep deprivation; slow wave sleep