Regional Cerebral Blood Flow During Script-Driven Imagery in Childhood Sexual Abuse-Related PTSD: A PET Investigation

TLDR

The study aimed to assess whether anterior limbic and paralimbic brain regions show differential activation during traumatic event recollection and imagery in women with childhood sexual abuse histories, comparing those with PTSD to those without. Using positron emission tomography, researchers measured normalized regional cerebral blood flow while participants performed script‑driven recollection and imagery of traumatic and neutral autobiographical events, recording psychophysiologic responses and subjective emotional ratings. Traumatic event recollection and imagery produced greater orbitofrontal cortex and anterior temporal pole activation in PTSD participants, whereas the comparison group showed stronger anterior cingulate gyrus activation; PTSD participants also exhibited larger decreases in bilateral anterior frontal regions and left inferior frontal gyrus compared to controls.

Abstract

The purpose of this study was to determine whether anterior limbic and paralimbic regions of the brain are differentially activated during the recollection and imagery of traumatic events in trauma-exposed individuals with and without posttraumatic stress disorder (PTSD).Positron emission tomography (PET) was used to measure normalized regional cerebral blood flow (CBF) in 16 women with histories of childhood sexual abuse: eight with current PTSD and eight without current PTSD. In separate script-driven imagery conditions, participants recalled and imagined traumatic and neutral autobiographical events. Psychophysiologic responses and subjective ratings of emotional state were measured for each condition.In the traumatic condition versus the neutral control conditions, both groups exhibited 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 cingulate gyrus were greater in the comparison group than in the PTSD group. Regional 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.The recollection and imagery of traumatic events versus neutral events was accompanied by regional CBF increases in anterior paralimbic regions of the brain in trauma-exposed individuals with and without PTSD. However, the PTSD group had greater increases in orbitofrontal cortex and anterior temporal pole, whereas the comparison group had greater increases in anterior cingulate gyrus.