Experiential avoidance as a moderator of the relationship between behavioral inhibition system sensitivity and posttraumatic stress symptoms

Preliminary evidence suggests that high emotional reactivity, in conjunction with maladaptive self-regulatory processes, increases one's vulnerability to develop psychopathology. In the present study, associations between behavioral inhibition system (HIS) and behavioral activation system (BAS) sensitivity, experiential avoidance (EA) and trauma-related outcomes (i.e., posttraumatic stress symptoms [PTSS]) were examined in a sample (N=851) of female college students who had experienced at least one traumatic event. Positive associations were observed between HIS sensitivity, EA, and PTSS. In addition, EA moderated the relationship between BIS sensitivity and PTSS, with participants high in HIS sensitivity and high in EA reporting significantly more PTSS than participants high in BIS sensitivity and low in EA. No association was observed between BIS sensitivity and PTSS for participants low in EA. These findings suggest that an unwillingness to experience unwanted private events, in conjunction with increased BIS sensitivity, contributes to PTSS severity. Further, there was a positive association and a negative association found between PTSS and BAS-Drive and BAS-Reward Responsiveness, respectively. A marginally significant EA x BAS-Fun Seeking interaction was also observed. Present findings suggests the importance of pursuing an etiological model of posttraumatic stress disorder in which neurobiological factors (i.e., BIS/BAS sensitivity) and self-regulatory processes (i.e., EA) interact to produce psychopathology. (C) 2011 Elsevier Ltd. All rights reserved.