Acute response to psychological trauma and subsequent recovery: No changes in brain structure

We used magnetic resonance imaging to study brain structure in acute stress disorder (ASD) following a psychological trauma and after 4 weeks in remission. Whole-brain voxel-based morphometry and FreeSurfer analysis of the hippocampal formation and amygdala revealed no structural changes in ASD (n=75) compared with trauma-exposed individuals without ASD (n=60) and community controls (n=60). These results suggest that ASD, in contrast to posttraumatic stress disorder, is not characterized by structural brain alterations.