The Dyadic Effects of Posttraumatic Stress Symptoms on the Regulation of Respiratory Sinus Arrhythmia Following an Acute Stress Induction Among Couples

Objective: Posttraumatic stress symptoms (PTSS) can have detrimental influences on both individual and couple functioning, including how individuals respond to stressors and regulate emotions. Respiratory sinus arrhythmia (RSA) can serve as a key indicator of emotion regulation; however, few studies have examined psychophysiological stress reactions within a couple's context. Method: Forty-three couples (N = 86 individuals) with a trauma history were assessed for PTSS and RSA at baseline. One partner then completed a stressor task using a film-clip depicting sexual assault. Afterward, the couple was reunited and completed a dyadic discussion task where both partners' RSA was continuously measured while they discussed the stressed partner's thoughts and feelings about the stressful film-clip. Results: Moderated repeated measures actor-partner interdependence models were conducted, examining the self and coregulation of RSA and moderation of such regulation by PTSS. There was significant self-regulation from both partners, and a coregulation process whereby the nonstressed partner's RSA influenced the rate of change in RSA of their stressed partner. Additionally, greater PTSS in the nonstressed partner was associated with a weakening of both self and coregulation. Conclusion: Patterns of both self- and coregulation, within and between romantic partners emerged and illustrate the impact of PTSS within these dyadic physiologic processes. Findings have theoretical and clinical implications in physiological dyadic interactions and potential stress recovery, particularly emphasizing the relevance of examining biomarkers such as RSA among partners with a trauma history during recovery from stress.