VISUAL-IMAGERY AND PERCEPTION IN POSTTRAUMATIC-STRESS-DISORDER - A POSITRON EMISSION TOMOGRAPHIC INVESTIGATION

Background: Relative regional cerebral blood flow (rCBF) changes were measured in Vietnam combat veterans with and without posttraumatic str ess disorder (PTSD) during exposure to combat-related stimuli. Methods : Positron emission tomography was used to measure rCBF in 7 combat ve terans with PTSD (PTSD group) and 7 healthy combat veterans (control g roup) who viewed and generated visual mental images of neutral, negati ve, and combat-related pictures. Results: Unlike control subjects, sub jects with PTSD had increased rCBF in ventral anterior cingulate gyrus and right amygdala when generating mental images of combat-related pi ctures; when viewing combat pictures, subjects with PTSD showed decrea sed rCBF in Broca's area. Conclusions: Results suggest that ventral an terior cingulate gyrus and right amygdala play a role in the response of combat veterans with PTSD to mental images of combat-related scenes . Reexperiencing phenomena of PTSD, which often involve emotional visu al mental imagery, may be likewise associated with increased rCBF in t hese regions.