Schizo-obsessive comorbidity has been proposed as a subgroup of schizophrenia that shares behavioural and neural mechanisms of schizophrenia and obsessive-compulsive disorder. A previous study from Dr. Raymond Chan and his team members from the Neuropsychology and Applied Cognitive Neuroscience (NACN) Laboratory, CAS Key Laboratory of Mental Health, the Chinese Academy of Sciences have shown that a specific alteration in functional connectivity in the default mode network in patients with schizo-obsessive comorbidity. However, it is still not clear whether such alteration would also be extended to white matter connectivity.
Recently, Dr. Raymond Chan and his international collaborators have conducted a study to examine whether specific changes in white matter exist in patients with schizo-obsessive comorbidity and the relationship between such abnormalities and clinical parameters. They recruited 28 patients with schizo-obsessive comorbidity, 28 schizophrenia patients, 30 obsessive-compulsive disorder patients and 30 demographically matched healthy controls. They scanned their brain using Tract-based Spatial Statistics and Probabilistic Tractography and conducted support vector machine learning analysis to further examine white matter changes among the four groups. Their findings showed that patients with schizo-obsessive comorbidity exhibited decreased fractional anisotropy in the right sagittal stratum and the left crescent of the fornix/striatum terminalis, and increased structural connection probability mainly associated with the default mode network and the cortico-subcortical pathway. The machine learning results also showed that FA features could differentiate patients with schizo-obsessive comorbidity from the other three groups with an accuracy of 0.78. These changes indicate specific neural superimposed effects of combined schizophrenia and obsessive-compulsive symptoms, supporting the “double jeopardy hypothesis” of schizo-obsessive comorbidity.
Dr. Chan’s team is now working with his local and international collaborators on a set of task-based functional neuroimaging paradigms to systematically examine the similarity and uniqueness of these clinical patients. They hope that their research findings can help guide for the development of a precision brain science approach for clinical diagnosis and intervention psychosis spectrum disorders and obsessive-compulsive disorder
This study was supported by the National Key Research and Development Programme, the Beijing Municipal Science & Technology Commission Grant, the Beijing Training Project for the Leading Talents in Science & Technology, the Strategic Priority Research Programme (B) of the Chinese Academy of Science, and the CAS Key Laboratory of Mental Health.
The paper is now available from Schizophrenia Bulletin
Wang, Y. M., Yang, Z. Y., Cai, X. L., Zhou, H. Y., Zhang, R. T., Yang, H. X., Liang, Y. S., Zhu, X. Z., Madsen, K. H., S？rensen, T. A., M?ller, A., Wang, Z., Cheung, E. F. C., Chan, R. C. K.* (in press). Identifying schizo-obsessive comorbidity by tract-based spatial statistics and probabilistic tractography. Schizophrenia Bulletin, DOI: https://doi.org/10.1093/schbul/sbz073
Wang, Y. M., Zou, L. Q., Xie, W. L., Yang, Z. Y., Zhu, X. Z., Cheung, E. F. C., S?rensen, T. A., M?ller, A., Chan, R. C. K. * (2019). Altered functional connectivity of the default mode network in patients with schizo-obsessive comorbidity: A comparison between schizophrenia and obsessive-compulsive disorder. Schizophrenia Bulletin, 4(1), 199-210.
Wang, Y. M., Zou, L. Q., Xie, W. L., Yang, Z. Y., Zhu, X. Z., Cheung, E. F. C., S?rensen, T. A., M?ller, A., Chan, R. C. K. * (2018). Altered grey matter volume and cortical thickness in patients with schizo-obsessive comorbidity. Psychiatry Research Neuroimaging, 276, 65-72.
Institute of Psychology