Electrophysiologic retinal testing: Testing done to diagnose specific disorders of the retina, including inherited retinal diseases, the effects of toxic drug exposure on the retina, and the presence of foreign bodies within the eye.

The most commonly performed electrophysiologic test is the electroretinogram (ERG). Other electrophysiologic tests include electro-oculography (EOG), visual evoked response (VER), dark adaptometry, and special color vision testing.

The ERG measures the electrical response of the retina to flashes of light. The EOG measures the difference in the electrical potential between the front and back of the eye in response to dark and light. The VER measures the electrical potential resulting from a visual stimulus. Dark adaptometry measures the period of time which passes before the retina regains its maximal sensitivity to low amounts of light when going from conditions of bright light to darkness.