When good news falls short: Prospective role of positive belief updating in predicting post-trauma distress.

Adaptive functioning relies on the ability to update beliefs in response to new information. However, belief updating is often optimistically biased, with individuals more readily revising their beliefs in response to desirable (good news) than to undesirable (bad news) information. Deficiencies in positive updating have been linked to psychological distress. However, the temporal association between positive belief updating and psychological distress remains unclear. Given that trauma exposure strongly challenges prior beliefs and places heightened demands on belief updating, the present study aims to examine whether baseline belief updating abilities prospectively predict the tendency to develop depressive and posttraumatic stress symptoms 3 months following trauma exposure. In a community sample of Israeli adults (N = 117), belief updating was assessed at T0 (six months prior to the October 7th attacks) using a validated belief updating task. Depressive and posttraumatic stress symptoms were assessed at T0 and at T1 (three months following the October 7th attacks), along with cumulative trauma exposure. Reduced positive updating was associated with higher posttraumatic stress at T1, even when controlling for trauma exposure and baseline (T0) symptoms. Findings suggest that erosion in optimistic bias can prospectively predict psychological distress following trauma exposure. Belief updating may represent a cognitive process relevant to vulnerability and resilience following trauma and stress.