SLEEP ONSET ABNORMALITIES IN DEPRESSED ADOLESCENTS

Sleep measures were obtained in 16 depressed and 21 control adolescent s following I week Of adherence to a uniformly imposed and strictly en forced sleep/wake schedule. Three nights of baseline electroencephalog raphic (EEG) sleep on the same 10:00 PM to 7:00 AM schedule revealed p rolonged sleep latency and reduced rapid eye movement (REM) latency in the depressed adolescents. Following baseline measures, sleep was res tricted for 2 nights (10:00 PM-4:00 AM) and measures of recovery sleep were obtained showing further sleep latency differences. There was no evidence for delta sleep changes or sleep continuity differences in d epressed adolescents. These results suggest that control over sleep/wa ke schedules is an important methodological issue in adolescent sleep studies. Furthermore, the findings are consistent with a larger body o f evidence indicating that dysregulation near sleep onset represents a primary psychobiological change in early-onset depression.