[Influence of the cerebellum on ocular statics and visual tracking movements (author's transl)].

It has long been admitted that the vestibular cerebellum plays a major role in the control of slow ocular movements. A study of 12 patients with localized lesions of the paleo- and neo-cerebellum has demonstrated that these recent structures also participate in the organization of visual tracking movements. These patients often have disturbances of ocular statics as well, and this can be the cause of slow movement disturbances. In most cases, however, ataxia of the tracking movement is not related to a statics disorder, but on the contrary, to disturbances of the movement itself. This suggest that the two cerebellar levels involved in ocular motility are related to two different types of movement strategies: vestibular cerebellar tracking having the very elementary function of maintaininf fixation within the overall picture of postural regulation: neo-cerebellar tracking, on the contrary, being already the beginning of voluntary motility.