Individuals who experience military combat obviously endure extreme stress, and this exposure leaves many diagnosed with the psychiatric condition of post-traumatic stress disorder, or PTSD.
PTSD is associated with several abnormalities in brain structure and function. However, as researcher Roger Pitman explains, "Although it is tempting to conclude that these abnormalities were caused by the traumatic event, it is also possible that they were pre-existing risk factors that increased the risk of developing PTSD upon the traumatic event's occurrence."
Drs. Kasai and Yamasue along with their colleagues sought to examine this association in a new study published in the March 15th issue of Biological Psychiatry.
The authors measured the gray matter density of the brains of combat-exposed Vietnam veterans, some with and some without PTSD, and their combat-unexposed identical twins using a technology called magnetic resonance imaging (MRI). The detailed images provided by the MRI scans then allowed the investigators to compare specific brain regions of the siblings. They found that the gray matter density of the pregenual anterior cingulate cortex, an area of the brain involved in emotional functioning, was reduced in veterans with PTSD, but not in their twins who had not experienced combat. According to Dr. Pitman, “this finding supports the conclusion that the psychological stress resulting from the traumatic stress may damage this brain region, with deleterious emotional consequences.”