title: Sleep EEG provides evidence that cortical changes persist into late adolescence.
abstract: OBJECTIVE
  To examine developmental changes in the human sleep electroencephalogram (EEG) during late adolescence.
  
  
  METHODS
  A 4-bed sleep laboratory.
  
  
  METHODS
  Fourteen adolescents (5 boys) were studied at ages 15 or 16 (initial) and again at ages 17 to 19 (follow-up).
  
  
  METHODS
  N/A.
  
  
  RESULTS
  All-night polysomnography was recorded at each assessment and scored according to the criteria of Rechtschaffen and Kales. A 27% decline in duration of slow wave sleep, and a 22% increase of stage 2 sleep was observed from the initial to the follow-up session. All-night spectral analysis of 2 central and 2 occipital leads revealed a significant decline of NREM and REM sleep EEG power with increasing age across frequencies in both states. Time-frequency analysis revealed that the decline in power was consistent across the night for all bands except the delta band. The decreases in power were most pronounced over the left central (C3/A2) and right occipital (O2/A1) derivations.
  
  
  CONCLUSIONS
  Using longitudinal data, we show that the developmental changes to the sleeping EEG that begin in early adolescence continue into late adolescence. As with early adolescents, we observed hemispheric asymmetry in the decline of sleep EEG power. This decline was state and frequency nonspecific, suggesting that it may be due to the pruning of synapses known to occur during adolescence.
authors.affiliation: E.P. Bradley Sleep Research Laboratory, Providence, RI 02906, USA. Leila_Tarokh@brown.edu
authors.forename: Leila
authors.initials: L
authors.lastname: Tarokh
authors.forename: Eliza
authors.initials: E
authors.lastname: Van Reen
authors.forename: Monique
authors.initials: M
authors.lastname: LeBourgeois
authors.forename: Ronald
authors.initials: R
authors.lastname: Seifer
authors.forename: Mary A
authors.initials: MA
authors.lastname: Carskadon
mesh_terms: D000293:Adolescent; D002540:Cerebral Cortex / Q000254:growth & development* / Q000502:physiology; D004569:Electroencephalography; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D017286:Polysomnography; D012890:Sleep / Q000502:physiology*; D012894:Sleep Stages / Q000502:physiology; D012895:Sleep, REM / Q000502:physiology; D055815:Young Adult