Multivariate pattern classification of pediatric Tourette syndrome using functional connectivity MRI
Published online on February 01, 2016
Abstract
Tourette syndrome (TS) is a developmental neuropsychiatric disorder characterized by motor and vocal tics. Individuals with TS would benefit greatly from advances in prediction of symptom timecourse and treatment effectiveness. As a first step, we applied a multivariate method – support vector machine (SVM) classification – to test whether patterns in brain network activity, measured with resting state functional connectivity (RSFC) MRI, could predict diagnostic group membership for individuals. RSFC data from 42 children with TS (8–15 yrs) and 42 unaffected controls (age, IQ, in‐scanner movement matched) were included. While univariate tests identified no significant group differences, SVM classified group membership with ~70% accuracy (p < .001). We also report a novel adaptation of SVM binary classification that, in addition to an overall accuracy rate for the SVM, provides a confidence measure for the accurate classification of each individual. Our results support the contention that multivariate methods can better capture the complexity of some brain disorders, and hold promise for predicting prognosis and treatment outcome for individuals with TS.
In the present paper, we used a multivariate approach – namely support vector machine (SVM) classification – to discriminate children with Tourette syndrome (TS) and unaffected controls based on resting state functional connectivity data. While univariate analyses found no significant group differences, SVM classified group membership with ~70% accuracy. Thus, there are multivariate patterns of functional connectivity that can discriminate TS from controls.