Decreased cerebral blood flow of thalamus in PTSD patients as a strategy to reduce re-experience symptoms

Abstract

OBJECTIVE: To investigate alterations of regional cerebral blood flow (rCBF) in subjects with post-traumatic stress disorder (PTSD). METHOD: Using [99Tcm]-hexamethyl propylenamino oxime single photon emission computed tomography, the rCBF under resting condition was compared between 19 survivors of the Taegu subway fire with PTSD and 19 comparison subjects. RESULTS: PTSD patients showed a decreased rCBF in the right thalamus and an increased rCBF in the right superior parietal lobe relative to comparison subjects (corrected P < 0.05). The rCBF in the right thalamus positively correlated with the severity of current re-experience symptoms in PTSD subjects. CONCLUSION: Our finding of the thalamic rCBF decrease in PTSD patients may be a strategy to reduce re-experience symptom, by evading the process of external and internal information which can evoke traumatic memory. In addition, the parietal rCBF increase in our PTSD patients might be related to altered information processing in PTSD.