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bioRxiv · 10.1101/459560

Atypical functional connectivity in Tourette syndrome differs between children and adults

Abstract

BackgroundTourette syndrome (TS) is a neuropsychiatric disorder characterized by motor and vocal tics that typically change over development. Whether and how brain function in TS also differs across development has been largely understudied. Here, we used functional connectivity MRI to examine whole brain functional networks in children and adults with TS.\n\nMethodsMultivariate classification methods were used to find patterns among functional connections that distinguish TS from controls separately for children and adults (total N = 202). We tested whether the patterns of connections that classify diagnosis in one age group (e.g., children) could classify diagnosis in another age group (e.g., adults). We also tested whether the developmental trajectory of these connections were altered in TS.\n\nResultsPatterns of functional connections that distinguished TS from controls were generalizable to an age-matched independent test set, but not to other age groups. While diagnostic classification was successful in children and adults separately, the connections that best distinguished TS from controls were age-specific. When contextualized with typical development, some functional connections exhibited accelerated maturation in childhood TS, while others exhibited delayed maturation in adulthood TS.\n\nConclusionsOur results demonstrate that brain networks are differentially altered in children and adults with TS, and that the developmental trajectory of affected connections is disrupted. These findings further our understanding of neurodevelopmental trajectories in TS and carry implications for future applications aimed at predicting the clinical course of TS in individuals over development.

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Nielsen, A., Gratton, C., Church, J. A., Dosenbach, N. U., Black, K. J., Petersen, S. E., Schlaggar, B. L., Greene, D. J.. 2018-11-01. Atypical functional connectivity in Tourette syndrome differs between children and adults. https://doi.org/10.1101/459560

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