Functional neuroimaging investigations of motor networks in Tourette syndrome

Motor and vocal tics are the core symptom of Tourette syndrome (TS). Tic generation seems to develop throughout the known motor pathways. This review focuses on functional neuroimaging in order to check this assumption. Also it elucidates the alterations and interactions of motor networks in TS depending on different contexts and circumstances like resting state, spontaneous tic movements, suppression of tics and premonitory urges, voluntary goal-oriented movements as well as electrophysiological neuronal stimulation. In general, the primary tic generating motor network uses the basic motor pathways differently, interacts with secondary sensorimotor networks and neuronal systems of cognitive behavioural control in a merely hierarchical manner, changing during neurodevelopment.