Abstract
BACKGROUND: Childhood adversity is associated with susceptibility to posttraumatic stress disorder (PTSD) in adulthood. PTSD and childhood adversity are linked to white matter microstructure, yet the role of white matter as a potential neural mechanism connecting childhood adversity to PTSD remains unclear. In the current study, we investigated the potential moderating role of previous childhood adversity on longitudinal changes in white matter microstructure and posttraumatic stress symptoms following a recent traumatic event in adulthood. METHODS: As part of the AURORA (Advancing Understanding of RecOvery afteR traumA) study, 114 recent trauma survivors completed diffusion-weighted imaging at 2 weeks and 6 months after exposure. Participants reported on prior childhood adversity and PTSD symptoms at 2 weeks, 6 months, and 12 months posttrauma. We performed region of interest (ROI) analysis using fractional anisotropy (FA) and whole-brain correlational tractography using quantitative anisotropy (QA) to index associations between white matter microstructure changes and prior adversity. RESULTS: ROI-based analyses did not identify significant associations between childhood adversity and changes in FA. Whole-brain correlational tractography revealed that greater childhood adversity moderated the QA changes within threat and visual processing tracts including the cingulum bundle and inferior fronto-occipital fasciculus (IFOF). QA changes within the cingulum bundle and IFOF were associated with changes in PTSD symptoms between 2 weeks and 6 months. CONCLUSIONS: Our findings suggest that temporal variability in threat and visual white matter tracts may be a potential neural pathway through which childhood adversity confers risk for PTSD symptoms after adulthood trauma. Future studies should take the temporal properties of white matter into consideration to better understand the neurobiology of childhood adversity and PTSD.