David Rotenberg1, James Kennedy2, 3, Benoit Mulsant, 34, Aristotle N. Voineskos1, 3, Mallar Chakravarty1, 5
1Research Imaging, Center for Addiction and Mental Health, Toronto, Ontario, Canada; 2Neuroscience, Center for Addiction and Mental Health, Toronto, Ontario, Canada; 3Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada; 4Geriatric Mental Health, Center for Addiction and Mental Health, Toronto, Ontario, Canada; 5Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
Identification of compromised WM pathways, along with better understanding of underlying genetic risk factors, will help to further our knowledge of schizophrenia etiology and the development of new schizophrenia biomarkers. A novel tract-based ROI statistical analysis is presented, that uses probabilistic tractography to segment tracts of interest across individuals, defining spatially restricted alignment-invariant skeletons for TBSS analysis, and has the potential to enable unique and focused investigations of WM tracts that may not be available through standard TBSS. Our ROI-based analysis provides evidence of altered thalamo-frontal circuity conferred by schizophrenia-risk gene NRXN1 variants, The right and left frontal-thalamic tracts were found to have statistically significant FA deficits in C/C homozygotes compared to C/T heterozygotets when corrected for multiple comparisons, whereas this effect was not distinguishable using standard TBSS.