Abnormal oculovestibular response.

In normal individuals, the visual and vestibular systems interact through a common subcortical center located near the vestibular nuclei. When the patient is healthy, this interaction allows appropriate integration of what might otherwise be conflicting information regarding environmental motion and moving within the environment. In patients with active peripheral vestibular lesions, such as those seen in Meniere's disease, this delicate interaction loses effectiveness. In such patients, optokinetic stimuli are capable of precipitating episodes of incapacitating vertigo with its associated vegetative symptoms (abnormal oculovestibular response--AOVR). Since the brainstem is unable to accommodate for active peripheral lesions, suffering may be prolonged for many years. Vestibular nerve section, however, converts this active lesion to a static peripheral lesion, allowing for brainstem compensation and cessation of optokinetic-induced vertiginous symptoms.