title: Impairment of reaction time among children awakened during stage 4 sleep.
abstract: OBJECTIVE
  Sleep inertia refers to impairments in cognitive/motor performance and the tendency to return to sleep after awakening. As part of a project studying the effect of different types of 100 decibel (dB) sounds on awakening children during stage 4 sleep (S4S), we hypothesized that children with the greatest impairment in auditory arousal during S4S, manifested by the inability to either awaken to 100 dB sounds or successfully perform a self-rescue sequence (SRS), would have greater impairments in reaction time (RT) upon awakening than children who awoke and successfully accomplish a SRS.
  
  
  METHODS
  Observational study.
  
  
  METHODS
  Pediatric hospital-based sleep center.
  
  
  METHODS
  Healthy children aged 6-12 years.
  
  
  METHODS
  N/A.
  
  
  RESULTS
  RT was measured in 44 children approximately 90 minutes before bedtime and again after awakening by either 100 dB alarms or manually during the first and second cycles of S4S. Overall, mean and median RT slowed significantly by 37% and 22%, respectively, from baseline. Slowing of RT was most evident in the youngest children (aged 6-7 years) and after awakening from the second S4S cycle. Impairments in RT were not significantly different among children who successfully awakened to the alarm and performed a SRS compared with children who did not.
  
  
  CONCLUSIONS
  The degree of slowing of RT was not significantly different among children who awakened and performed an SRS compared with children who did not. The greatest slowing of RT was seen among younger children and after awakening from the second S4S cycle.
authors.affiliation: Columbus Children's Hospital, Department of Pediatrics, Columbus, OH, USA. splaingm@pediatrics.ohio-state.edu
authors.forename: Mark
authors.initials: M
authors.lastname: Splaingard
authors.forename: John
authors.initials: J
authors.lastname: Hayes
authors.forename: Gary A
authors.initials: GA
authors.lastname: Smith
mesh_terms: D000161:Acoustic Stimulation; D000367:Age Factors; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D011597:Psychomotor Performance; D011930:Reaction Time; D012449:Safety; D020921:Sleep Arousal Disorders / Q000523:psychology; D012894:Sleep Stages; D013018:Sound Spectrography; D014851:Wakefulness