Research is reviewed concerning the interrelationships among cardiodynamics, blood pressure control mechanisms, somatic activity, and the stimulus parameter of active vs passive coping. Emerging evidence suggests that with passive coping such as classical aversive conditioning, the heart is more under vagal control which is directionally linked with somatic activity, while blood pressure is more dominated by vascular processes. With active coping such as shock avoidance, the heart is under greater sympathetic control which is directionally independent of concomitant somatic activity, while cardiac influences on blood pressure become more dominant. Several current psycho physiological issues are discussed including the possible significance of these effects for cardiovascular disease processes.

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This study was designed to examine the hypothesis that certain behavioral demands may tend to trigger sympathetic mechanisms which result in metabolically excessive cardiac output elevations. Oxygen consumption and cardiac output adjustments during a contrived reaction‐time shock‐avoidance task were compared to a cold pressor test in healthy young male adults. The linear cardiac output/oxygen consumption relationship generated by performance on a graded exercise task was used to assess the metabolic appropriateness of cardiac output adjustments to the reaction‐time task and cold pressor. The reaction‐time task was generally found to evoke metabolically excessive increases in cardiac output, while cardiac output adjustments to cold pressor were more consistent with changes in metabolic demands. However, the tasks were associated with similar heart rate responses, with a significant attenuation in stroke volume during cold pressor accounting for the differential alterations in cardiac output. This finding suggests a limited reliability for heart rate as an index of cardiac performance. The effects of propranolol, which was employed to evaluate the role of sympathetic influences, indicated that beta‐adrenergic mechanisms were responsible for mediating the cardiac output response to the reaction‐time task, but only partially contributed to the cold pressor response. Post‐hoc analyses of individual differences in cardiovascular reactivity to the reaction‐time task suggest that, for hyperreactive individuals, the coping responses evoked by this task may lead to tissue overperfusion with oxygen, thereby providing a stimulus for autoregulatory vascular reflexes which may be associated with the etiology of hypertensive disease.

In three experiments involving young adult males, beta‐adrenergic influences on heart rate and carotid dP/dt were evaluated as a function of the degree of individual control over stressful events. Beta‐adrenergic effects were more pronounced under conditions in which the subjects were either led to believe they had control or where some control was actually provided, i.e., a shock avoidance task. Beta‐adrenergic influences were either minimal or rapidly dissipated under conditions where no control was possible, i.e., the cold pressor, a pornographic film, inescapable shocks, or conditions which provided ready mastery of the task. Where beta‐adrenergic effects were maximal, systolic blood pressure was more appreciably elevated while diastolic blood pressure was less elevated than when beta‐adrenergic effects were minimal. A pharmacological blocking agent (propranolol) was used in one experiment to specify the extent the various cardiovascular changes were influenced by beta‐adrenergic activity. The results are discussed with respect to issues concerning stimulus parameters, blood pressure control mechanisms, individual differences in cardiovascular reactivity, and some methodological problems of the current study.

The purpose of this paper is to propose a scheme as to how the activities of the heart might be viewed in psychophysiological endeavors and theory. It is proposed that a necessary starting point is the metabolically relevant relationship between cardiac and somatic processes. This relationship is relevant to both an understanding of basic behavioral processes as well as psychopathological states of cardiac functioning. For these purposes, a strategy is outlined which, among other things, involves the evaluation of the influence of the cardiac innervations. Here it is proposed that heart rate most unequivocally reflects vagal activity, while the contractile properties of the heart manifest most unequivocally sympathetic effects. The implications of these arguments are discussed with regard to current studies involving the operant modification of heart rate. It is suggested that the significance of current operant to both issues of learning theory and psychopathology of cardiac function is questionable.