Default mode network resting-state functional connectivity and event centrality in adult acute trauma survivors.

Research has identified functional connectivity abnormalities in the default mode network (DMN), a functional brain network theorized to be involved in self-referential processes, among trauma survivors. Event centrality (EC) is an important cognitive component of posttrauma stress disorder (PTSD) development that heavily involves self-referential processing and autobiographical memory. However, the impact of EC in a neuroimaging context remains underexplored. This study investigated the relationships between DMN resting-state functional connectivity (rsFC) and event centrality and the mediating effects of adverse psychological outcomes on DMN rsFC and event centrality among acute traumatic injury survivors. Two hundred and fifteen adult participants were recruited from a Level I trauma center after sustaining a traumatic injury, followed by resting-state fMRI scanned at 2-4 weeks post-injury and self-report questionnaires collected at 2-4 weeks and 3-, 6-, and 12 months post-injury. Event centrality, at 3- and 12-month, was significantly associated with measures of adverse psychological outcomes, and EC at 12-month was significantly associated with the rsFC of two nodes of the DMN: the lateral parietal cortex and hippocampus. In addition, specific adverse psychological outcomes significantly mediated this relationship between rsFC and event centrality. This novel neuroimaging finding suggests potential mechanisms that contribute to increased psychological distress and greater event centrality in traumatic injury recovery.