Baylor Study Finds Changed Brains in PTSD Victims

A ten-year study by Baylor University researchers into the root causes of post-traumatic stress disorder (PSTD) that studied 100 Viet Nam veterans and their identical, non-combat veteran twins has found significant evidence that trauma stress changes the makeup of the brain.

MRI head scan by Max Brown of Sydney, Australia courtesy stock.XchngThe study, which is focusing on the links between genetics and brain anatomy to discover the base mechanisms of PTSD in the hopes of someday countering its affects in trauma sufferers, found that the ventromedial prefrontal cortex area of the brain, gray matter which activates when we make a decision, was significantly smaller in combat veterans with PTSD than in non-combatants.

“We discovered a number of abnormalities in PTSD combat veterans not shared with their twins and … we infer that the abnormality was caused by combat,” Pitman said. “One of these is increased heart rate response when the combat veteran is startled. Another example is loss of gray matter in the rostral anterior cingulated cortex, which plays a role in inhibiting the fear response.”

In addition to trauma causing a reduction in the ventromedial prefrontal cortex, researchers also discovered a genetic marker that suggests sensitivity to trauma: a smaller hippocampal volume. Before, brain researchers have noted that PTSD sufferers have smaller hippocampi than non-sufferers and theorized that the hippocampus was reduced by trauma, but in fact this is not the case for the hippocampus, as non-combatant twins also had small hippocampi. This suggests that some people are genetically more sensitive to trauma than other people, which explains why a small segment of the population responds to trauma in an extremely negative fashion while many others can walk away relatively unscathed.

Researchers’ current conclusions are that it is the combination of the stress reduction in the prefrontal cortex and the genetic marker that lead to PTSD.