Background: Evidence is accumulating that suggests borderline personality disorder (BPD) and posttraumatic stress disorder (PTSD) are related to small hippocampal size. Psychotic symptoms are frequent in both disorders. Psychotic spectrum disorders are known to be related to abnormalities of temporoparietal cortices.
Methods: Using structural magnetic resonance imaging (3D-MRI), parietal cortex and hippocampal volumes were assessed in 30 young women with BPD who had been exposed to severe childhood sexual and physical abuse and in 25 healthy control subjects.
Results: Compared with control subjects, BPD subjects had significantly smaller right parietal cortex (-11%) and hippocampal (-17%) volumes. The parietal cortex of borderline subjects showed a significantly stronger leftward asymmetry when compared with control subjects. Stronger psychotic symptoms and schizoid personality traits in borderline subjects were significantly related to reduced leftward asymmetry. Stronger trauma-related clinical symptoms and neuropsychologic deficits were significantly related to smaller hippocampal size.
Conclusions: Our results are consistent with previous findings of small hippocampal size in BPD and PTSD. Reduced right parietal cortex size in individuals with BPD may reflect a neurodevelopmental deficit of the right hemisphere.