The cerebellum makes almost every aspect of eye movements appropriately calibrated to provide clearest vision, by both making immediate, on-line correction and ensuring long-term adaptation. The vestibulocerebellum is important for gaze holding, smooth
pursuit, and VOR. The dorsal vermis and underlying fastigial nucleus are important for an accurate programming of saccade and smooth pursuit. In addition to its traditional roles in conjugate eye movements, it plays some role in the control of the eye
alignment. Eye movement abnormalities with cerebellar disease can be classified into three syndromes: 1) The syndrome of flocculus and paraflocculus (impaired smooth pursuit, vestibuloocular reflex (VOR) cancellation, and fixation suppression; gaze
evoked, downbeat, centripetal, rebound, and cross-coupled nystagmus; postsaccadic drift or glissades; inappropriate VOR; impaired VOR adaptation and learning), 2) The syndrome of nodulus and ventral uvula (prolonged VOR due to maximized velocity
storage; impaired habituation of VOR; positional, down-beat, and periodic alternating nystagmus; impaired dumping or tilt suppression of postrotational nystagmus; inappropriate reaction to gravito-inertial acceleration; ocular tilt reaction), 3) The
syndrome of dorsal vermis and underlying fastigial nucleus (saccadic dysmetria; mild deficits of smooth pursuit and motion perception)
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