What is a Visual Evoked Potential Test?

A visual evoked potential test, or VEP for short, is performed to measure the electrical activity of the entire visual system. As our eyes look at an object, light enters our eyes and is converted into an electrical signal by the retina. The signal created by the retina then travels through the optic nerve back to the occipital cortex. The occipital cortex is the portion of the brain that is directly responsible for vision. The purpose of the VEP test is to measure the strength of the electrical signals sent from the retina to the occipital cortex, via the optic nerve, as well as how long the signals take to get there.

How to Prepare for a VEP Test

For this test, a Marano Eye Care team member will prepare your skin to be clean and dry so that 3 sensory pads can be placed on your head. Once the pads are properly positioned, a computer screen placed in front of the patient will begin to show a series of black and white patterns that seem to flip over and over again. The patient is required to look at the screen, and nothing else. Depending on initial diagnosis, the patient may be asked to cover one eye at a time during the testing to record individual eye results. As the test is taking place, the sensory pads are collecting data on the electrical signals being sent from the retina to the occipital cortex and recording the data to a computer that will provide our team with a final results report.