Test Overview
Vision is the result of electrical signals that travel between the retina and the part of the brain involved with vision (occipital cortex).
Electrophysiology tests check to see how well this visual nerve pathway sends the electrical signals needed for vision. These tests measure electrical activity that occurs in your eye when you look at something.
Electrophysiology includes different tests that measure how well the retina works. It can help check for diseases of the retina. The tests may also help diagnose and evaluate different kinds of vision and health problems.
Electroretinography (ERG)
ERG measures the retina's electrical response while you look at different patterns or flashes of light. An ERG test can check for diseases and problems of the retina.
A full-field ERG can check how well your entire retina is working. A multifocal ERG (mfERG) tests just part of the retina. It can check for diseases of the macula and for central vision loss.
Electro-oculography (EOG)
EOG tests how well electrical currents are working in the whole eye. It is done to check for certain eye and retina problems.
Visual evoked response (VER)
VER tests the electrical activity in the whole visual pathway, from the eyes to the parts of the brain involved with vision.
Like ERG, this test measures electrical activity when the eye responds to looking at something. A VER test can find problems by showing how brain waves respond to certain things you look at during the test.
