Respiratory Sinus Arrhythmia in Cognitive Behavioral Therapy for Posttraumatic Stress Symptoms in Children: Preliminary Treatment and Gender Effects.

Cognitive behavioral therapy (CBT) is an efficacious treatment for posttraumatic stress disorder (PTSD) symptoms, but the effect of CBT on physiological indicators is largely unknown. Respiratory sinus arrhythmia (RSA) is an established parasympathetic marker of self-regulatory capacity and stress responsivity. The present study tested if and how resting RSA and RSA reactivity changed following treatment among a sample of children (n = 48) who experienced at least one traumatic event and presented with PTSD symptoms. RSA reactivity was measured in response to personalized trauma-related scripts. Results indicated that changes in RSA after treatment were dependent on pretreatment resting levels of RSA, with individuals with high and low pretreatment resting RSA levels appearing to converge over time in both resting RSA and RSA reactivity by the 3-month follow up. Specific to RSA reactivity, a sex difference was evident, as following treatment, females showed less RSA withdrawal whereas males showed more RSA withdrawal. PTSD symptoms were significantly reduced after CBT but symptom change was not associated with pretreatment resting RSA levels. Overall, these results suggest that there may be multiple physiological patterns within children with PTSD and the direction of the physiological changes after CBT may depend on initial differences in resting RSA levels.