The impact of a loss of control over threat on stress reactivity

Uncontrollable negative events often elicit higher acute anxiety and stress than negative situations within our control. Beyond these immediate effects, some studies showed that experiences of control over negative situations may promote future resilience against stress-related impairments. Conversely, it has been shown that loss of control over threat may be more detrimental than a consistent lack of control. Whether loss of control affects stress reactivity remains poorly understood. The current study investigated the impact of loss of control over a threat on stress reactivity in humans. Eighty participants were equally assigned to either a Continuous Control or a Loss of Control group to perform a threat (un)controllability task in which they either lost or maintained control over aversive electrical stimuli. Subsequently, participants were exposed to an acute stress induction procedure (Socially Evaluated Cold Pressor Test). The experiment included assessments of perceived stress and control, salivary alpha-amylase and cortisol, blood pressure, and electrodermal activity. Additionally, participants completed questionnaires about emotion regulation strategies, general sense of control, and distress tolerance. Our results did not support the prediction that experiencing loss of control over threat heightens biological and perceived stress markers acutely or that it enhances biological reactivity to a subsequent stressor. However, we found that loss of control increased perceived stress in the subsequent task, specifically among females, which may partly reflect sex-specific stimulus duration differences inherent to the used yoking procedure. Further research is necessary to corroborate our findings and to explore the observed sex-specific vulnerability to loss of control.