Brain Abnormalities in PTSD
Brock, Stephen E., National Association of School Psychologists. Communique
Sunny Windingstad, Sunnyside Unified School District, Tucson, AZ.
K ari et al. (2006) conductedametaanalysis of 50 studies to better under stand various brain structures among those with posttraumatic stress disorder (PTSD), those exposedto trauma who were not diagnosed with PTSD (trauma-exposed controls), and control subjects without trauma exposure.
Method. The researchers grouped studies based on methodology and brain region examined. Analysis one included a control group of trauma-exposed controls or nontrauma-exposed controls compared to those with PTSD andlooked at hippocampal hemisphere sizes. Fifteen studies of subjects with PTSDversus nontrauma-exposed subjects, twelve of PTSD versus non-PTSD trauma-exposed subjects, and six of non-PTSD versus nontrauma-exposed subjects were included in the meta-analysis. In analysis two, nine studies were grouped according to MRI acquisition protocols while a tenth was grouped according to the anatomical borders used to delineate the brain structures being examined. Finally, analysis three consisted of a moderator analysis where a cluster analysis of all studies was broken down first by a meta-analysis of volumetric differences ofbrain structures, which was followed by tests of group differences to determine potential moderators and meta-analysis of those clusters that were homogenous for a variable.
Results. Trauma, whether associated with PTSD or not, is correlated with smaller hippocampal volume. However, when compared to those exposed to trauma, those with PTSD and who were unmedicated exhibited even smaller volumes. Volumetric differences occurred across several brain structures and were not limited to the hippocampus, and relative to adults children demonstrated different structural variations. …