The synchronous changes of subjective and autonomic responses to neutral and "stress' stimulation in patients with involutional depression and normal subjects were investigated. The stimuli employed were individually determined during a pretest interview and consisted of neutral, emotionally loaded and "mental task' testing periods of equal duration presented at random. GSR, heart rate and finger plethysmography measures were taken during administration of these stimuli, while the subjective anxiety experienced during the same periods of stimulation was rated by the subjects on a five-point scale. The results suggest that measures of synchrony between subjective and autonomic response systems may differentiate (1) patients from controls and (2) certain types of emotional stimuli from others in patients. Implications for further research regarding the qualitative differentiation of the arousal associated with emotional stimuli are discussed.