What is visual evoked potential? (VEP)
A visual evoked potential is an evoked potential caused by a visual stimulus, such as an alternating checkerboard pattern on a computer screen. Responses are recorded from electrodes that are placed on the back of your head and are observed as a reading on an electroencephalogram (EEG). These responses usually originate from the occipital cortex, the area of the brain involved in receiving and interpreting visual signals.
When is the VEP used?
A doctor may recommend that you go for a VEP test when you are experiencing changes in your vision that can be due to problems along the pathways of certain nerves. Some of these symptoms may include:
- Loss of vision (this can be painful or non-painful)
- Double vision
- Blurred vision
- Flashing lights
- Alterations in color vision or
- Weakness of the eyes, arms or legs.