Posttraumatic stress, stressor controllability, and avoidance

Cognitive models of posttraumatic stress disorder (PTSD) propose that overgeneralized beliefs involving lack of control are important to development and maintenance of the disorder. In the absence of a strong evidence base regarding controllability in PTSD, we examined whether PTSD was associated with increased sensitivity to alterations in controllability over stressful stimuli. Participants with (PTSD+, n = 113) and without (PTSD-, n = 115) symptoms were recruited from a crowdsourcing platform and randomized to receive either Controllable aversive noise, Uncontrollable aversive noise, or No noise before completing a subsequent aversive noise task in which all participants lost control over aversive noise. Participants then completed an avoidance task that assessed the delay between selecting and viewing a potentially distressing stimulus. PTSD+, but not PTSD-, participants who initially had control over an aversive noise but then lost the control were more avoidant of subsequent distress than those who either did not previously have control over the noise or was not exposed to the noise. Importantly, this pattern was evident in females but not males. These results highlight that people with PTSD are vulnerable to the adverse effects of losing control, and this can contribute to avoidance. The findings that this vulnerability is heightened in females may shed light on the greater risk of females to develop PTSD.