Additive Burden of Abnormal Diffusivity in the Brainwith Schizophrenia: A Diffusion Tensor Imaging Studywith Public Neuroimaging Data

ABSTRACT

Objective@#Diffusion tensor imaging has been extensively applied to schizophrenia research. In this study, we counted the number ofabnormal brain regions with altered diffusion measures in patients with schizophrenia to enumerate the burden of abnormal diffusivityin the brain. @*Methods@#The public neuroimaging data of the COBRE project from SchizConnect were used for the study. The studied dataset consistedof data from 57 patients with schizophrenia and 71 healthy participants. FreeSurfer and FSL were applied for image processingand analysis. After verifying 161 regions of interest (ROIs), mean diffusion measures in every single ROI in all study participants weremeasured and normalized into Z-scores. Each ROI was then defined as normal or abnormal on the basis of a cutoff absolute Z-score of1.96. The number of abnormal ROIs was obtained by each diffusion measure. @*Results@#The numbers of ROIs with increased radial diffusivity and increased trace were significantly larger in the patient group than inhealthy participants. @*Conclusion@#Thus, the patient group showed a significant increase in abnormal ROIs, strongly indicating that schizophrenia is notcaused by the pathology of a single brain region, but is instead attributable to the additive burden of structural alterations within multiplebrain regions. Psychiatry Investig 2020;17(4)341-349