Comparing the Role of Aberrant Salience and Dissociation in the Relation between Cumulative Traumatic Life Events and Psychotic-Like Experiences in a Multi-Ethnic Sample.

Exposure to traumatic life events (TLE) is a risk factor for psychosis. Yet, a dearth of studies examines factors linking TLE to psychosis, while considering differences in TLE frequency. This study investigated dissociation and aberrant salience as mediators and moderators of the relation between three TLE groups (none, 1-3 TLE and 4+ TLE) and psychotic-like experiences (PLE) in a multi-ethnic sample of 816 emerging adults. The participants completed self-report inventories of PLE (Prodromal Questionnaire), TLE (Life Events Checklist), dissociative experiences (Dissociative Symptoms Scale), and aberrant salience (Aberrant Salience Inventory). As expected, groups with higher TLE frequency endorsed higher PLE. Parallel mediation models indicated that, while aberrant salience mediated the relation between both levels of cumulative traumatic experiences (1-3 TLE and 4+ TLE) and PLE, dissociation only mediated the relation between exposure to at least four different traumatic experiences and PLE. The moderation results showed that risk of PLE was highest among individuals with 1-3 TLE who endorsed dissociation. Our results suggest that, while aberrant salience processing explains why TLE may relate to higher psychosis risk, dissociation's role in this relation is dependent on the number of different TLE exposures.