Nystagmus is an abnormality in the physiological processes of the eye. This disease leads to the fact that a person either experiences accelerated movement of the pupils, or they remain in a stationary position while awake. With nystagmus of the vertical ocular muscles, the eye rotates up and down. The disease manifests itself as a symptom of brain damage, occurring in acute and chronic forms. Ophthalmologists can diagnose the disease, after confirming its presence, and select therapy.