Cardiovascular reactivity and adaptation to recurrent psychological stress: The moderating effects of evaluative observation

The impact of evaluative observation on cardiovascular reactivity and adapt ation to recurrent psychological stress was evaluated in 162 undergraduate men and women. All participants performed three mental arithmetic tasks wit h or without evaluative observation. Impedance cardiographic, blood pressur e, task performance, and stress appraisal measures were recorded for each t ask. Evaluative observation moderated the effects of task repetition on car diac reactivity but not vascular reactivity. The introduction of evaluative observation disrupted cardiac adaptation, resulting in a resurgence of bet a -adrenergic cardiac reactivity (p < .005), whereas the removal of evaluat ive observation promoted cardiac adaptation. Evaluative observation also in creased stress appraisals and slowed task performance. The results support the dual process theory of habituation, rather than stimulus comparator the ory, but only partially support cognitive appraisal theory.