Post-Traumatic Stress Disorder (PTSD) | Psychiatry Neuroimaging Laboratory

Project Description

Our group has also been actively involved in MRI studies of post-traumatic stress disorder (PTSD). These studies have been undertaken in collaboration with researchers in Israel (Dr. Arieh Shalev) and at the Manchester, NH Veterans Affairs Medical Center (Dr. Mark Gilbertson) and Dr. Roger Pitman who is now at Massachusetts General Hospital. Quantitative volumetric MRI techniques have been used to explore neuroanatomical correlates of chronic, combat-related PTSD. One study reported diminished left and right hippocampal volume in PTSD Vietnam combat veterans (see Gurvits et al., 1996). Moreover, these volume reductions were associated with severity of combat exposure, suggesting that the severe stress of military combat both damages the hippocampus and is associated with and PTSD. A similar study was undertaken with Gulf war veterans in Israel, and these data are have shown similar findings (Bonne et al., 2001).

Hippocampus (green), Fornix (blue) and Mammilary Bodies (gray) are shown in 3D.

A study reported in Nature-Neuroscience (Gilbertson et al., 2002) evaluated MR brain morphometry of the hippocampus in monozygotic twins discordant for PTSD. The PTSD twin was diagnosed with PTSD as a result of combat exposure in the Vietnam War. The twin aspect of this study was important as it showed that individuals discordant for PTSD showed reduced hippocampal volume compared with twins where PTSD was present in neither twin. This finding suggests that there may be a predisposition or vulnerability factor involved in the genesis of PTSD.

We plan to continue to use imaging tools to increase the precision of brain measurements, an important factor in studying disorders such as schizophrenia and PTSD where the differences from controls are quite small and subtle.