title: Sleepiness and Cognitive Performance among Younger and Older Adolescents across a 28-Hour Forced Desynchrony Protocol.
abstract: OBJECTIVE
  Quantify the homeostatic and circadian effects on sleepiness and performance of adolescents. Examine age-related changes in homeostatic and circadian regulation of sleepiness and performance by comparing younger and older adolescent groups.
  
  
  METHODS
  Three-week laboratory study including 12 cycles of a 28-h forced desynchrony protocol.
  
  
  METHODS
  Controlled laboratory environment with individual sleep and performance testing rooms and shared common areas.
  
  
  METHODS
  Twenty-seven healthy adolescents including 16 females. Ages ranged from 9.6-15.2 years and participants were split into younger (n = 14 ages 9-12) and older (n = 13 ages 13-15) groups based on median age split of 13.0 years.
  
  
  METHODS
  N/A.
  
  
  RESULTS
  Testing occurred every 2 h during scheduled wake periods. Measures included sleep latency during repeated nap opportunities and scores from a computerized neurobehavioral assessment battery including a 10-min psychomotor vigilance task, a digit symbol substitution task, and the Karolinska Sleepiness Scale. Significant main effects of circadian and homeostatic factors were observed, as well as several circadian and homeostatic interaction effects. Age group did not have a significant main effect on sleep and performance data. A significant interaction of circadian phase and age group was found for sleep latency, with younger adolescents showing greater circadian modulation than older teens during the circadian night.
  
  
  CONCLUSIONS
  Adolescents demonstrated a similar pattern of response to forced desynchrony as reported for adults. Sleepiness and performance were affected by homeostatic and circadian factors, and age group did not interact with homoeostatic and circadian factors for subjective sleepiness and most performance metrics. Younger adolescents had a shorter latency to sleep onset than older during the circadian bin spanning 4 to 8 h after the onset of melatonin secretion.
authors.affiliation: Sleep/Wake Research Centre, Massey University, Wellington, New Zealand.|E.P. Bradley Hospital Sleep and Chronobiology Research Laboratory, Providence, RI.
authors.forename: Lora J
authors.initials: LJ
authors.lastname: Wu
authors.affiliation: E.P. Bradley Hospital Sleep and Chronobiology Research Laboratory, Providence, RI.|Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI.
authors.forename: Christine
authors.initials: C
authors.lastname: Acebo
authors.affiliation: Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI.
authors.forename: Ronald
authors.initials: R
authors.lastname: Seifer
authors.affiliation: E.P. Bradley Hospital Sleep and Chronobiology Research Laboratory, Providence, RI.|Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI.|Centre for Sleep Research, School of Psychology, Social Work, and Social Policy, University of South Australia, Adelaide, Australia.
authors.forename: Mary A
authors.initials: MA
authors.lastname: Carskadon
mesh_terms: D000293:Adolescent; D001288:Attention / Q000502:physiology; D002648:Child; D002940:Circadian Rhythm / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D005260:Female; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D008297:Male; D008550:Melatonin / Q000378:metabolism; D011597:Psychomotor Performance; D012894:Sleep Stages / Q000502:physiology*; D013997:Time Factors; D014851:Wakefulness / Q000502:physiology
chemical_list: D008550:Melatonin
keywords: adolescents; cognitive performance; forced desynchrony; sleepiness