This study compared hippocampal volume in 26 Vietnam veterans with combat-related posttraumatic stress disorder (PTSD) to 22 comparison subjects with similar demographic and medical characteristics. Using MRI, researchers found that PTSD patients had a statistically significant 8% smaller right hippocampal volume compared to comparison subjects, but no differences in other brain regions like the caudate or temporal lobe. Deficits in short-term verbal memory, measured by the Wechsler Memory Scale, were associated with smaller right hippocampal volume in PTSD patients only. These findings support the hypothesis that PTSD is linked to reduced right hippocampal volume, which may contribute to memory deficits. The study also found no significant correlation between hippocampal volume and other brain structures or memory functions in either group, suggesting the findings may be specific to the right hippocampus. The results indicate that PTSD may be associated with structural changes in the brain, particularly in the hippocampus, which could affect memory function. The study controlled for factors such as age, education, and alcohol abuse, and found that the relationship between hippocampal volume and memory deficits remained consistent even after adjusting for these variables. The findings suggest that hippocampal volume may be a useful biomarker for PTSD and could have implications for the diagnosis and treatment of the disorder.This study compared hippocampal volume in 26 Vietnam veterans with combat-related posttraumatic stress disorder (PTSD) to 22 comparison subjects with similar demographic and medical characteristics. Using MRI, researchers found that PTSD patients had a statistically significant 8% smaller right hippocampal volume compared to comparison subjects, but no differences in other brain regions like the caudate or temporal lobe. Deficits in short-term verbal memory, measured by the Wechsler Memory Scale, were associated with smaller right hippocampal volume in PTSD patients only. These findings support the hypothesis that PTSD is linked to reduced right hippocampal volume, which may contribute to memory deficits. The study also found no significant correlation between hippocampal volume and other brain structures or memory functions in either group, suggesting the findings may be specific to the right hippocampus. The results indicate that PTSD may be associated with structural changes in the brain, particularly in the hippocampus, which could affect memory function. The study controlled for factors such as age, education, and alcohol abuse, and found that the relationship between hippocampal volume and memory deficits remained consistent even after adjusting for these variables. The findings suggest that hippocampal volume may be a useful biomarker for PTSD and could have implications for the diagnosis and treatment of the disorder.