Although dysfunctions in both basal ganglia and cerebellum in dystonia are well documented, the functional relationships between these two important motor control networks remains unclear in the context of dystonia. Here the investigators propose to tackle this issue by associating cerebellar stimulations with functional analysis using fMRI in dystonic patients.~The working hypothesis is that the primary torsion dystonia (PTD) pathophysiology involves dysfunction of striatum that is amplified by dysregulation of the cerebello-thalamo-striatal pathway.~The project is to study dystonia forms resulting primarily from dysfunctions of the striatum (patients with mutation of the ADCY5 gene) and compare them with patients with putative dysfunction of the cerebellum (patients with mutation of the PRRT2 gene) and healthy controls. In these patients, the investigators will look for (1) how cerebello-thalamo striatal pathway can be influenced by striatal dysfunctions and (2) whether cerebellar stimulation may prevent (or worsen?) the disrupted activity in the basal ganglia and (3) whether striatum-related dystonia share the same abnormal network with another form of dystonia resulting from another dysfunction (patients with PRRT2 mutation).
The investigators will study the relationship between the basal ganglia and the cerebellum in dystonia by associating cerebellar stimulations with functional magnetic resonance imaging analysis.