PTSD's underlying symptom dimensions and relations with behavioral inhibition and activation

• We examined the relation between PTSD factors and BIS/BAS dimensions in a primary care sample.
• PTSD's avoidance and dysphoria factor had a significantly greater association with BIS compared to BAS.
• PTSD's re-experiencing factor related more to BIS than BAS.
• PTSD's avoidance significantly mediated the relation between BIS/BAS and PTSD's dysphoria.

Reinforcement sensitivity theory (RST) stipulates that individuals have a behavioral activation system (BAS) guiding approach (rewarding) behaviors (Gray, 1971 and Gray, 1981), and behavioral inhibition system (BIS) guiding conflict resolution between approach and avoidance (punishment) behaviors (Gray & McNaughton, 2000). Posttraumatic stress disorder (PTSD) severity overall relates to both BIS (e.g., Myers et al., 2012 and Pickett et al., 2011) and BAS (Pickett et al., 2011). Using a more refined approach, we assessed specific relations between PTSD's latent factors ( Simms, Watson, & Doebbeling, 2002) and observed variables measuring BIS and BAS using 308 adult, trauma-exposed primary care patients. Confirmatory factor analysis and Wald chi-square tests demonstrated a significantly greater association with BIS severity compared to BAS severity for PTSD's dysphoria, avoidance, and re-experiencing factors. Further, PTSD's avoidance factor significantly mediated relations between BIS/BAS severity and PTSD's dysphoria factor.