Nonverbal expressiveness and EMG activity in tension headache sufferers and controls.

This study explored the relationship between musculoskeletal responses and nonverbal expressiveness in response to psychosocial stress. Muscle-contraction headache subjects and normal controls were confronted with a psychological stressor while forehead and neck EMG activity were recorded. Indices of nonverbal expressiveness (head and hand movements, facial tension, facial activity, and facial expressiveness) were obtained concomitantly with the muscle data. The headache subjects showed greater muscle activation than the controls in response to stress, greater evidence of facial tension, and less evidence of facial and bodily expressiveness. Overall, these data provided support for the notion that under some conditions a negative relationship exists between expressiveness and somatic activation.