Structural signature of trauma: white matter volume in right inferior frontal gyrus is positively associated with use of expressive suppression in recently traumatized individuals

Background: Differences in grey and white matter structure have been found between trauma-exposed individuals with and without PTSD. Yet, it remains unclear which functional processes are underlying these volumetric changes. Avoidance- and suppression-based emotion regulation strategies are candidates of interest since they play an important role in the development and maintenance of PTSD. Method: We used voxel-based morphometry to examine differences in brain structure in 20 recently trauma-exposed individuals and 20 healthy controls in respect of their relation to emotion regulation. Results: We found a significantly larger white matter volume close to the right inferior frontal gyrus (rIFG) in patients compared to healthy controls. White matter volume close to the rIFG was positively correlated with expressive suppression. Conclusion: The region of volumetric white matter difference in our study overlaps with brain regions previously associated with executive functioning and inhibitory control, functions that are known to be impaired in PTSD. Our findings support the idea that impaired executive functions in PTSD might be compensated by suppression-based emotion regulation strategies.