The existing evidence of the relation between chronic-background (BG) stress level and cardiovascular (CV) and cortisol responses to acute stressors is inconsistent. We hypothesize that the manner in which BG stressors influence acute responses is determined by the perceived controllability of the BG stressor. Differences in perceptions of control over one's BG stressor can lead to differences in effort invested in, and appraisals of acute stressor tasks, and it is these factors that influence differential CV and cortisol responses. Low perceptions of control over one's background stressor are expected to yield dampened physiological acute stressor responses. Yet, perceiving control over one's background stressor is expected to yield heightened physiological acute stressor responses. To test these ideas, we have selected to work with caregivers of family members having Alzheimer's disease. This is a BG stressor that has wide variance in the perceived controllability one has over the situation. Further, caregiver status alone has not differentiated the acute stressor physiological responses of caregivers vs. matched controls. The primary goal of the proposed study is to explore the role that perceptions of control over caregiving have in influencing CV and cortisol responses to acute stressor tasks. A related goal is to determine the mechanisms through which perceived control acts to influence these physiological responses. To accomplish the goals set forth in the current study, task appraisals, effort invested, and CV and cortisol responses of three groups will be compared. These three groups consist of caregivers perceiving their situation to be either controllable, or uncontrollable, and age-, ethnicity- and gender-matched non-caregivers.
