Sleep study on patients with severe brain damage--polysomnographical examination.

Polysomnograms were obtained for five severely brain damaged patients, and phasic sleep parameters-body movements (BMs) and rapid eye movements (REMs)-were examined. CT scanning of their brains demonstrated large low density areas in the bilateral hemispheres. In the three patients with flat EEG, sleep could only be classified into two stages; one with REMs[R(+)] and one without REMs[R(-)]. In the other two patients, stage R(-) was further classified into two stages according to the EEG findings. Gross movements (GMs) showed a synchronous pattern in all the patients. GMs and low angle REMs decreased in number while twitch movements and high angle REMs showed almost the same incidences as in normal controls. Localized movements showed marked variations among the patients. It was suggested that, except for normal uncoordinated asymmetrical GMs, BMs did not necessarily require higher brain structures for their generation.