Expressive tendencies and physiological response to stress.

This study assessed the effects of natural expressive tendencies on physiological response to stress. Male undergraduates were unobtrusively observed while watching a stressor videotape. On the basis of the subjects' facial responsiveness to the film, a group of 23 natural expressers and 22 natural inhibitors were selected and exposed to a threat of shock situation during which heart rate, respiration rate, skin conductance, and facial expressions were monitored. In accord with the discharge model of emotion, natural inhibitors were less facially expressive and more physiologically reactive to the shock threat than were natural expressers. The results also demonstrated that overt expressivity is stable over time and situation. On personality measures, natural expressers scored significantly higher on Mehrabian's empathic tendency scale, thus supporting the efficacy of this paper-and-pencil instrument as a measure of non-verbal responsiveness. The two groups did not differ on measures of self-esteem, introversion--extraversion, or locus of control. The results are discussed in terms of the discharge model as a descriptive metaphor and not a causal theory.