Disruption of hippocampal connectivity in children and adolescents with schizophrenia - A voxel-based diffusion tensor imaging study

Introduction: One hypothesis that unifies the diversity of symptoms associated with schizophrenia involves the disruption of connectivity between brain regions. As white matter provides rapid and efficient communication between brain regions, this study was initiated to assess the early disruption of white matter pathways in children and adolescent with schizophrenia. Materials and methods: Diffusion tensor images were acquired on 14 children and adolescents with schizophrenia, one subject with schizoaffective disorder, and 15 age and gender matched controls. The DTI images were acquired in twelve directions on a 3 T Siemens Trio scanner. The images were transformed into fractional anisotropy and mean diffusivity maps and a group analysis was performed using SPM2. Results: Children and adolescent patients with schizophrenia demonstrated a significant decrease in FA and associated increase in AD in the left posterior hippocampus (p < 0.001, Bonferroni corrected on the cluster-level). These diffusion differences were not statistically significant when IQ was used as a covariate in the analysis. Discussion: These findings suggest hippocampal white matter abnormalities that present early in the development of schizophrenia. The lack of significant differences when IQ is used as a covariate suggests that this hippocampal region is associated with cognitive changes associated with schizophrenia.