IN TWO PREVIOUS studies1-2 11 known somnambulists, seven children and four adults, were studied for 61 uninterrupted subject nights with electroencephalogram (EEG), electromyogram (EMG), and eye movements (EOG) continuously monitored throughout the night.3 A total of 89 somnambulistic incidents was observed and recorded including 11 episodes of sleepwalking and 78 of sitting up or crawling about the bed. All of the sleepwalking incidents except one occurred in child somnambulists. All of the somnambulistic incidents occurred in nonrapid eye movement (NREM) sleep, typically Stages 3 and 4 and not during rapid eye movement periods (REMP's) which are most frequently associated with dreaming. In addition, measurements of total sleep, awake, and REMP times as well as the sleep cycles were similar for the somnambulists, as compared to normal children of the same ages.2,4 The somnambulistic incidents characteristically began with a paroxysmal burst