Task Influences on Behaviourally-Elicited Cardiovascular Reactions

Abstract

Task characteristics strongly influence both the patterning and magnitude of behaviourally-elicited cardiovascular responses. The major stimulus determinants of cardiovascular reactions include: (a) attentional requirements for sensory intake versus sensory rejection; (b) situational demands for active versus passive coping; (c) the nature of emotional or affective states elicited; and (d) associated task attributes such as novelty, difficulty and the presence of performance-contingent incentives. The interest of many clinical investigators in the assessment of psychophysiologic responses follows from recent speculation that a cardiovascular hyperreactivity to stress may be implicated in coronary heart disease (CHD) and/or essential hypertension. In this regard, it is important to examine effects of stimulus variables on the measurement of individual differences in cardiovascular reactivity and on the relationship of such differences to CHD, hypertension and risk for cardiovascular disease. Available data are mixed concerning the stability of idiosyncratic heart rate and blood pressure responses across varying stimulus conditions; some investigators report substantial intertask correlations, whereas others find only moderate, or little, consistency of responses across tasks. Concerning samples of clinical interest, an increased cardiovascular reactivity among hypertensive patients and in persons with a family history of hypertension is observed most frequently during tasks that require subjects to engage in active coping or mental work (sensory rejection). Situational variables are also important in studies of the psychophysiologic correlates of the Type A (coronary-prone) behaviour pattern. Here, the heightened cardiovascular reactivity of Type A individuals appears to be influenced both by the formal nature of the task employed (ie, active versus passive coping, etc) and by the interpersonal and instructional context in which experimental stimuli are presented.