Phasic muscular activity and muscular tonus in rem sleep

Abstract

The phasic EMG which is recorded from the submental muscle during REM sleep is quantitatively evaluated and expressed as the % phasic EMG. As for normal subjects, the % phasic EMG is distributed from 2 to 5%. In the patients with idiopathic Parkinsonism who showed muscle rigidity in the upper limbs, the % phasic EMG was considerably higher than in normal subjects. However, there was no relation between finger tremor and the % phasic EMG. In Huntington's chorea, the % phasic EMG was zero. From these observations, it is supposed that the abnormal state of the muscle tonus of the whole body has relation to the % phasic EMG obtained during REM sleep. However, this relation was not found in three schizophreniacs who showed a slight increase of muscle tonus. Finally, some consideration was given as to the physiological and biochemical mechanisms which participate in muscle rigidity and in the appearance of the phasic EMG during REM sleep. © 1973, Kurume University School of Medicine. All rights reserved.