[Neurology of eye movements]

Eye movements are necessary for clear and stable vision, for which images of the world should be brought to the fovea and be held steady on the retina. The main types of eye movements consist of saccadic eye movements, vergence, vestibular eye movements, smooth pursuit eye movements and eye movements for visual stabilization. Saccades are fast eye movements and have consistent relationship between their peak velocity and the size of the movements. The burst neurons in the brainstem are the generator of saccades and receive projections from the frontal eye field, supplementary eye field, parietal eye field, basal ganglia, superior colliculus and cerebellum. Saccades are evaluated by a speed and accuracy of the size. There are different types of saccade, such as visually triggered saccades, antisaccades, memory-guided saccade and predictive saccades. The specific test paradigms of saccades may show the localization and the type of diseases. Opsoclonus, flatter-like oscillation, ocular myoclonus, square-wave jerks are characteristic involuntary eye movements. Syndromes of the paramedic pontine reticular formation, medial longitudinal fascicules and one-and-a-half syndrome are caused by disease of the pons.