A comparison of EMG and SCL in normal and depressed subjects.

Skin conductance level (SCL) and electromyograms (EMGs) recorded from three muscle sites were compared for 15 female hospitalized psychiatric patients meeting diagnostic criteria for primary affective disorder and 15 age-and race-matched controls. The depressed subjects had significantly lower SCL and significantly higher resting EMG levels recorded from one muscle site. Electromyogram and SCL were not found to be significantly correlated with each other or with measures of anxiety or depression for the patients with primary affective disorder. Normal controls, however, showed significant correlations between a measure of depression and both EMG and SCL. These results are discussed with suggestions for future research.