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.

Effects of thematically relevant and general stressors on specificity of responding in asthmatic and nonasthmatic subjects

Twenty-nine mild asthmatics and 12 nonasthmatics were exposed to three films of varying emotional content to assess differential patterns of physiological response in the cardiac, ventilatory, and bronchial systems. Results indicated that only cardiac interbeat interval (IBI) and total respiratory resistance (RT) were reliable indices of reactivity. In a film of thematic relevance to asthmatics which depicted asthmatic children in a hospital setting, asthmatics evidenced sustained elevation of RT throughout the entire film with no reactivity in IBI. Nonasthmatics did not evidence any significant reactivity to the film. In a film of a generally stressful nature which depicted industrial accidents, asthmatics evidenced elevated RT in response to the accident scenes. Both asthmatic and nonasthmatic subjects responded to the post-accident periods with increases in IBI. In a film depicting a mother giving up her child for adoption, asthmatics responded to the relinquishing of the child with elevated RT. These results are discussed in terms of the necessity of evolving a comprehensive theory of specificity patterns in psychosomatic disorders which goes beyond models of symptom specificity and stimulus-response specificity, neither of which can adequately account for these results. The results are further seen as supporting the utility of selecting stressors of thematic relevance to asthmatics and measuring symptom-relevant indices of physiological reactivity to isolate these specificity patterns in response to stress.

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.

Efficacy of pattern feedback for the dissociation of heart rate and respiration rate

The present study assessed the efficacy of pattern feedback for producing integrative and dissociative patterns of heart rate (HR) and respiration rate (RR). 60 uninformed subjects were assigned to six groups in which beat-by-beat feedback was contingent upon production of a specific pattern of increased ( ), decreased ( ), or unchanged (=) HR and RR during 11 feedback trials. Concomitant changes in respiratory volume and general activity (GA) were also recorded. Groups given feedback for HR and RR changes in the same directions (HR RR and HR RR ) ANd for changes in opposite directions (HR RR and HR RR ) were generally unable to produce the respective patterns, indicating that pattern feedback does not enable subjects to produce a wide range of HR-RR patterns. However, evidence of dissociation of HR and RR was obtained in the HR RR= and HR RR= groups in which HR changed significantly in the appropriate directions without significant changes in RR. These results are not consistent with the view that RR changes are necessary for HR control, although significant concomitant changes in respiratory volume and GA indicated that HR control was non-specific relative to these variables.

Role of feedback in voluntary control of heart rate

The relative effectiveness of biofeedback techniques on the voluntary control of heart rate was examined by randomly assigning 32 Ss to one of four feedback conditions in a bi-directional heart-rate control task: (1) no feedback, (2) binary feedback--S was signaled when an interbeat interval had changed in the correct direction, (3) "real-time," proportional feedback--S was provided information about the relative duration of successive interbeat intervals, and (4) numerical, proportional feedback--each interbeat interval was represented as a numeral indicating its relationship to pre-trial mean by direction and magnitude. Significant over-all heart-rate changes were evidenced for both increase and decrease directions, but no differences were found between the feedback conditions. While these data suggest that feedback may be a relatively insignificant factor in voluntary heart-rate control, it was recommended that further investigation examine the role of feedback within the context of other training, mediating and motivational variables.