Regional cerebral blood flow during script-driven imagery in childhood sexual abuse-related PTSD: A PET investigation

Objective: The purpose of this study was to determine whether anterior limb ic and paralimbic regions of the brain are differentially activated during the recollection and imagery of traumatic events in trauma-exposed individu als with and without posttraumatic stress disorder (PTSD). Method: Positron emission tomography (PET) was used to measure normalized regional cerebral blood flow (CBF) in 16 women with histories of childhood sexual abuse: eig ht with current PTSD and eight without current PTSD. In separate script-dri ven imagery conditions, participants recalled and imagined traumatic and ne utral autobiographical events. Psychophysiologic responses and subjective r atings of emotional state were measured for each condition. Results: In the traumatic condition versus the neutral control conditions, both groups exh ibited regional CBF increases in orbitofrontal cortex and anterior temporal poles; however, these increases were greater in the PTSD group than in the comparison group. The comparison group exhibited regional CBF increases in insular cortex and anterior cingulate gyrus; increases in anterior cingula te gyrus were greater in the comparison group than in the PTSD group. Regio nal CBF decreases in bilateral anterior frontal regions were greater in the PTSD group than in the comparison group, and only the PTSD group exhibited regional CBF decreases in left inferior frontal gyrus. Conclusions: The re collection and imagery of traumatic events versus neutral events was accomp anied by regional CBF increases in anterior paralimbic regions of the brain in trauma-exposed individuals with and without PTSD. However, the PTSD gro up had greater increases in orbitofrontal cortex and anterior temporal pole , whereas the comparison group had greater increases in anterior cingulate gyrus.