Asynchronous cortical input and asthenopia

Abnormal delays in retinal-cortical transmission are typically associated with optic nerve disease. Clinically optic nerve diseases produce visual field abnormalities, decreased visual acuity, and color vision defects. Disease processes causing only interocular differences in retinal-cortical transmission properties are not easily detected. Patients with diseases causing interocular latency differences may complain of visual discomfort and perceptual distortions yet perform normally in standard clinical tests. A simple procedure to minimize differences in interocular latency and provide relief from visual disturbances arising from this abnormality is described.