Fear, Anxiety, and the Neuroimaging of PTSD

The clinical manifestations of Posttraumatic Stress Disorder (PTSD) include both fear and anxiety symptoms. Animal studies provide significant information about the neurobiological pathways involved in fear and anxiety and are relevant to the study of PTSD. These studies are reviewed along with Rauch's proposed neurobiologic model for PTSD. Neuroimaging findings in PTSD are summarized by region. Most neuroimaging studies to date have been provocation studies which present a trauma-related stimulus and measure response.While providing information about PTSD, these complex studies were not designed to target specific emotions. Studies which can specifically elicit fear or anxiety and evaluate associated brain regions, such as the bed nucleus of the stria terminalis (BNST) may provide a clearer understanding of the biologic underpinnings of PTSD and bridge the knowledge between animal neurobiology and human studies.