title: Dissipation of sleep pressure is stable across adolescence.
abstract: The sleep electroencephalogram (EEG) undergoes many changes during adolescence. We assessed whether sleep homeostasis is altered across adolescent development using two measures: the dissipation of slow-wave activity (SWA, 0.6-4.6Hz) across the night and the rate of build-up of SWA in the first non-rapid eye movement (NREM) sleep episode. Furthermore, we examined the association between homeostatic and circadian measures, by correlating the build-up of SWA in the first non-rapid eye movement (NREM) sleep episode with circadian phase. Finally, we compared the dissipation of SWA in individuals with (PH+) and without (PH-) a parental history of alcohol abuse/dependence. Twenty children (8 PH+) and 25 teens (10 PH+) underwent two consecutive polysomnographic recordings at ages 9/10 and 15/16 years and again 1.5-3 years later. Thirteen young adults (ages 20-23 years; no PH+) were assessed one time. The decay of Process S was modeled for each individual at each assessment using data from both recordings. Four parameters of Process S were derived for EEG derivation C3/A2: time constant of the decay, lower asymptote (LA), the level of S at sleep onset (S(SO)), and S(SO) minus LA. We found no change in these parameters between assessments for the children and teen cohorts. Between-subject analysis of the follow-up assessment for children (ages 11-13 years) and the initial assessment for teens (ages 15/16 years) showed no difference in these parameters, nor did follow-up assessment of teens (ages 17-19 years) compared to the single assessment of young adults (ages 20-23 years). Similarly, we observed no developmental changes in the rate of the build-up of SWA in the first NREM sleep episode for our within- and between-subject analyses, or a correlation between this measure and circadian phase for either cohort. With regard to parental alcohol history, we found no difference in the dissipation of sleep pressure between PH+ and PH- children and teens. These results indicate that the dissipation of sleep pressure does not change across adolescent development, is not correlated with circadian phase, and does not differ between PH+ and PH- children and teens.
authors.affiliation: Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland. Leila_Tarokh@brown.edu
authors.forename: L
authors.initials: L
authors.lastname: Tarokh
authors.forename: M A
authors.initials: MA
authors.lastname: Carskadon
authors.forename: P
authors.initials: P
authors.lastname: Achermann
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001921:Brain / Q000502:physiology*; D002648:Child; D015331:Cohort Studies; D004569:Electroencephalography; D005260:Female; D005500:Follow-Up Studies; D006706:Homeostasis; D006801:Humans; D008297:Male; D012815:Signal Processing, Computer-Assisted; D012890:Sleep / Q000502:physiology*; D012895:Sleep, REM / Q000502:physiology; D055815:Young Adult