Summary:Sleep patterns in nonmedicated hyperkinetic (n = 11) and normal control (n = 11) male children (8-12 years old) were compared to document possible sleep disturbance in hyperkinetic children. Electroencephalographic, electro-oculographic, electromyographic, and autonomic measures were monitored continuously for five consecutive nights. Analysis of sleep pattern variables revealed a significantly longer rapid eye movement onset latency (p < 0.05) and marginally significant greater absolute and relative amounts of movement time (p < 0.07) for the hyperkinetic group relative to controls. No other sleep parameters differentiated the groups. It was concluded that baseline tonic sleep parameters do not indicate marked sleep disturbance in hyperkinesis. The results were discussed within the context of hypothesized arousal dysfunction underlying this disorder.