Functional neural correlates of PTSD symptoms and trauma exposure in young adult combat veterans

Abstract

Studies of adult post-traumatic stress disorder (PTSD) suggest increased amygdala, insula, and dorsal anterior cingulate (dACC), but decreased ventromedial prefrontal cortex (vmPFC) and hippocampus activity in response to emotional stimuli. This network is involved in emotion regulation and fear extinction, and its dysregulation may underlie symptoms of PTSD. However, the contribution of childhood and adult trauma exposure to this neural dysfunction remains poorly understood. dACC activation observed in prior studies of PTSD may be more attributable to childhood and adult trauma exposure. In contrast, abnormal insula and hippocampal activation may be specific to the PTSD syndrome. The specificity of these results to threat, and not positive stimuli, is consistent with abnormalities in fear/threat processing associated with PTSD.