An investigation into the effects of social evaluation on cardiovascular and endocrine responses to the CO₂ stress test in humans

Abstract

The present study examined whether social evaluation could heighten individuals' physiological responses to the CO₂ stress test, and the hypothalamic-pituitary-adrenal (HPA) response in particular. Twenty-five healthy volunteers undertook the CO₂ test under three conditions: (i) standard CO₂ protocol, (ii) standard CO₂ protocol conducted in front of a full-length mirror (mirror) and (iii) standard CO₂ protocol conducted in front of a video camera deemed to be transmitting live images of the procedure to investigators evaluating participant performance (video). Despite counterbalancing for task order, there were significant differences in anger and depression among the conditions. Repeated measures analysis of variances (ANOVAs), controlling for these mood indices, revealed that salivary cortisol, heart rate and systolic blood pressure responses to the CO₂ test were not affected by social evaluation (i.e. mirror or video). Although the data provide no evidence that endocrine and cardiovascular responses to the CO₂ test are affected by social evaluation, the potency of the social evaluation manipulation in this study is in question. Thus, further research is warranted which includes evidence of, or instructions suggesting negative social evaluation.

Keywords::

• Acute stress
• blood pressure
• cortisol
• CO₂ stress test
• heart rate
• social evaluation

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.