The Interaction Between Behavioral Inhibition and Response Inhibition in Patients with Post-Traumatic Stress Disorder

Not all individuals exposed to traumatic events develop post-traumatic stress disorder (PTSD). Variations in susceptibility to PTSD diagnosis may be related to individual differences in personality and dysfunctional response inhibition. The present study examined the relationship between the Behavioral Inhibition System (BIS), a relevant personality trait, and response inhibition, a form of cognitive control necessary for trauma recovery, in relation to PTSD severity. Participants included a sample of seven adult veterans (2 female, 5 male) previously diagnosed with PTSD. Participants were rated on their BIS levels through questionnaires and performed a common response inhibition task, the Go/No-Go (GNG). As expected, BIS levels increased with PTSD severity and BIS scores were more predictive of PTSD score than GNG performance. In addition, arousal and re-experiencing symptoms were positively related to BIS scores where both arousal and re-experiencing symptoms were predictive of BIS. Performance on GNG was not significantly related to BIS or PTSD. Results suggest that trait BIS may be a vulnerability factor for PTSD diagnosis if exposed to traumatic events