Size of Brain Region May Impact How Well Exposure Therapy Works for PTSD

New research suggests that PTSD patients with a larger region of the brain that helps distinguish between safety and threat are more likely to respond to exposure-based therapy.

The study expands upon prior research that discovered having a smaller hippocampus is associated with increased risk of PTSD.

In the current study, researchers at Columbia University Medical Center (CUMC) and New York State Psychiatric Institute (NYSPI), examined the relationship between hippocampus volume, and response to treatment in 50 participants with PTSD and 36 trauma-exposed healthy controls.

The volume or size of the hippocampus was measured with magnetic resonance imaging.

The participants were evaluated at baseline and after 10 weeks, during which time the PTSD group had prolonged exposure therapy.

Exposure therapy is a type of cognitive-behavioral therapy that has been shown to help patients with PTSD discriminate between real and imagined trauma.

The study, published online in Psychiatry Research: Neuroimaging found that patients with PTSD who responded to treatment had greater hippocampal volume at the beginning of the study than non-responders to treatment.

The findings add to growing evidence that the hippocampus is key to distinguishing between cues that signal safety and those that signal threat.

“If replicated, these findings have important implications for screening and treating patients who have been exposed to trauma,” noted Yuval Neria, Ph.D., professor of medical psychology at CUMC, director of the PTSD Program at NYSPI, and senior author of the paper.

“For example, new recruits for military service may be scanned before an assignment to determine whether they are capable of dealing with the expected stress and trauma. Having a smaller hippocampus may be a contraindication for prolonged exposure to trauma.”

“While we only studied response to prolonged exposure therapy, future research may help to determine if PTSD patients with a smaller hippocampus respond better to other treatments such as medication, either alone or in combination with psychotherapy,” adds first author Mikael Rubin, M.A., a Ph.D. student at the University of Texas at Austin.

Source: Columbia University Medical Center/EurekAlert

Abstract of the brain photo by shutterstock.