Potential pathways through which social relationships mediate cardiovascular reactivity during stress

The quality and quantity of one's relationships have been reliably linked to morbidity and mortality. More recently, studies have focused on links between relationships and cardiovascular reactivity as a physiological mechanism via the stressbuffering hypothesis. This hypothesis suggests that social support moderates or buffers the impact of stressful events. However, not all social relationships are consistently positive and hence associated with stress-buffering influences. To examine the more causal role of relationships on health we experimentally manipulated different relationship types (supportive, aversive, indifferent, and ambivalent) through the interpersonal behavior of an experimenter and examined this influence on cardiovascular reactivity. Although we were unable to create ambivalence, manipulation checks revealed expected significant experimenter main effects on ratings of helpfulness and upset. More important, we found an experimenter positivity main effect on systolic blood pressure reactivity, such that participants interacting with the high positivity experimenter had significantly lower systolic blood pressure. Unexpectedly, male participants interacting with a high negativity experimenter showed significantly lower diastolic blood pressure change. These findings indicate that relationships may be beneficial to one's cardiovascular health, but gender may influence motivational processes that impact on cardiovascular reactivity.