The physiological basis of therapies for cerebellar ataxias.

Cerebellar ataxias represent a group of heterogeneous disorders impacting on activities of daily living and quality of life. Various therapies have been proposed to improve symptoms in cerebellar ataxias. This review examines the physiological background of the various treatments currently administered worldwide. We analyze the mechanisms of action of drugs with a focus on aminopyridines and other antiataxic medications, of noninvasive cerebellar stimulation, and of motor rehabilitation. Considering the cerebellum as a controller, we propose the novel concept of 'restorable stage'. Because of its unique anatomical architecture and its diffuse connectivity in particular with the cerebral cortex, keeping in mind the anatomophysiology of the cerebellar circuitry is a necessary step to understand the rationale of therapies of cerebellar ataxias and develop novel therapeutic tools.