Depressed patients who showed decreases in resting corrugator muscle tension levels, as measured electromyographically, also showed improvement in clinical symptoms, as assessed by the Hamilton Psychiatric Rating Scale over a 2-wk period. Patients showing good clinical improvement after 2 wk had resting pretreatment corrugator levels higher than those showing little clinical improvement, suggesting that corrugator activity might also serve as a forecaster of subsequent change. Darwin''s 1872 hypothesis concerning the role of the grief muscle in depression was supported. Psychophysiological recording of patterns of facial muscle activity may have value in the clinical assessment of depression and treatment effects.