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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.

Thirty married couples were studied during naturalistic interactions to determine the extent to which variation in marital satisfaction could be accounted for by physiological and affective patterns between and within spouses. The authors hypothesized that (a) compared to nondistressed couples' interactions, distressed couples' interactions would show greater physiological interrelatedness or "linkage," more negative affect, and more reciprocity of negative affect and (b) these differences would be more pronounced when the interaction was high in conflict (discussing a marital problem) as opposed to low in conflict (discussing the events of the day). Heart rate, skin conductance, pulse transmission time, and somatic activity from both spouses were analyzed using bivariate time-series techniques to derive a measure of physiological linkage. Self-report affective data (obtained using a video-recall procedure) were analyzed using sequential analyses to derive a measure of affect reciprocity. The hypotheses were strongly supported; 60% of the variance in marital satisfaction was accounted for using measures of physiological linkage alone. Additional nonredundant variance was accounted for by the other physiological and affective measures.

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.

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.