Leaving the door open: Trauma, updating, and the development of PTSD symptoms

Humans try to make sense of the world using hypotheses that were formed by prior experiences. After trauma, these hypotheses can be exaggerated and resistant to change. This may result in difficulties to update expectations regarding the negative outcomes associated with traumatic stimuli. Critically, it has been proposed that such difficulties may drive the development of posttraumatic stress disorder (PTSD). However, direct evidence on the associations between trauma and impaired expectation updating is still absent. Moreover, it remains unclear whether such an impairment is correlated with PTSD symptoms. To address these gaps, we compared the ability to update traumatic and neutral stimulus-outcome expectations in 81 active-duty firefighters. Participants completed a performance-based updating task and were assessed for PTSD symptoms. We predicted and found a selective impairment in updating trauma-related expectations. This impairment was evident for negative-to-positive but not for positive-to-negative updating. Moreover, impaired negative-to-positive updating was positively associated with PTSD symptoms. These findings support the predictive processing account of PTSD and suggest that strengthening updating processes could be an important goal for promoting resilience after trauma.