(PhysOrg.com) -- A specific region of the hippocampus, a brain structure that is essential to memory, is significantly smaller in veterans with post-traumatic stress disorder than in those without the condition, according to a study by researchers at the San Francisco VA Medical Center and University of California, San Francisco.
The researchers used magnetic resonance imaging to scan the brains of 40 veterans - 20 with combat-related PTSD and 20 without - and found that the region known as the CA3/dentate gyrus was more than 11 percent smaller on average in the veterans with PTSD.
Just as significantly, the CA1 region of the hippocampus, which shrinks as a part of normal aging, was not significantly affected in the veterans with PTSD, according to principal investigator Norbert Schuff, PhD, a senior research scientist at the SFVAMC Center for Imaging of Neurodegenerative Diseases and professor of radiology at UCSF.
The study appears in the March, 2010 issue of “Archives of General Psychiatry.”
“This is the first time in human subjects that PTSD has been shown to be associated with changes in certain specific hippocampal regions and not in others,” says Schuff.
The hippocampus, a finger-joint size structure found in both hemispheres of the brain, is essential for laying down memories, as well as for retrieving them, explains study author Thomas C. Neylan, MD, director of the PTSD program at SFVAMC and a professor of psychiatry at UCSF. He notes that recurring or intrusive memory of traumatic events is a common symptom of PTSD, “and thus the hippocampus is of great interest in PTSD research.” …