Impulsivity in Tourette Syndrome : Behavioral and Neuroimaging Study

Tourette syndrome (TS) is characterized by the presence of multiple vocal and motor tics. Behavioral disorders associated with TS are common, particularly impulsivity, anti-sociality and socially inappropriate behavior. Specifically, cognitive impulsivity could be the source of these troubles. Its anatomical substrates is based on connections between frontal and striatal areas. Initially, a battery of behavioral tests measuring different types of impulsivity (motor, cognitive and decision) will be administered on three groups of subjects: TS: 80 patients (40 patients treated and 40 untreated) and 40 healthy volunteers. Then, investigators will study the fronto-striatal connections in the TS group of 80 patients (40 patients treated and 40 untreated) compared to 40 healthy volunteers using neuroimaging techniques (3T MRI). The techniques used will be functional connectivity study of "resting state" MRI (RS-fMRI) combined with a reconstruction of white matter fibers by diffusion tensor imaging (DTI). Behavioral performance will be correlated with the correlation imaging data to highlight the functional anatomical substrates of impulsivity in patients with TS. Finally, investigators will look specifically using functional MRI activation, the anatomical and functional substrates of the three types of impulsivity (motor, cognitive and decision-making). Through this study, investigators hope to elucidate the anatomical and functional bases of cognitive impulsivity in patients with TS and thus lay the basis for more targeted treatments.