SLEEP EEG AND PERSISTENCE OF CORTICAL CHANGES IN ADOLESCENCE
Sleep EEG Provides Evidence that Cortical Changes Persist into Late Adolescence
Leila Tarokh, PhD1,2,3; Eliza Van Reen, PhD1,2; Monique LeBourgeois, PhD2,4; Ronald Seifer, PhD2,5; Mary A. Carskadon, PhD1,2
1E.P. Bradley Sleep Research Laboratory, Providence, RI; 2Department of Psychiatry and Human Behavior, The Warren Alpert Medical School of Brown University, Providence, RI; 3Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland; 4Department of Integrative Physiology, University of Colorado at Boulder, Boulder, CO; 5E.P. Bradley Hospital, East Providence, RI
To examine developmental changes in the human sleep electroencephalogram (EEG) during late adolescence.
A 4-bed sleep laboratory.
Fourteen adolescents (5 boys) were studied at ages 15 or 16 (initial) and again at ages 17 to 19 (follow-up).
Measurements and 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.
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.
Tarokh L; Van Reen E; LeBourgeois M; Seifer R; Carskadon MA. Sleep EEG provides evidence that cortical changes persist into late adolescence. SLEEP 2011;34(10):1385–1393.