Visual/Auditory Evoked Response (VER / BAER)

Visual Evoked Response Test (VER)

The VER studies the functioning of the visual pathways, especially the optic nerves. The eye is visually stimulated with moving squares and the conduction is traced from the eye to the center of vision in the cortex of the brain.

Although your vision may seem normal to you, this test may still find problems in the brain that could not be detected by any other means.

This is a non-invasive, painless test, in which the function of the optic nerve is studied. The patient is to have clean hair with no hairspray, oils, or gels. Do not come with wet hair. Eat meals and take medications as usual.

The patient is seated in a chair and five disc electrodes are applied to the head with cream. An eye patch is applied over the right eye and the patient watches a checkerboard pattern on a screen. The checkerboard pattern is the stimulus to the optic nerve and a computer displays how the nerve functions. When the left eye is complete, the right eye is studied.

The patients’ job is to stay awake and alert and watch one distinct square in the middle of the screen. The entire test, including application, takes about 30 minutes.

It is important to remember your eye glasses, if worn for distance, and to stay awake during this test.


Brainstem Auditory Evoked Response Test (BAER)

The BAER studies the deep structures of the brain by stimulating the ear with a sound and recording its condition through the brain. Although your hearing may seem normal to you, this test may still find problems in the brain that could not be detected by any other means.

This is a non-invasive, painless test, in which function of the Auditory Nerve through to the brainstem is determined.

The patient should have a clean scalp without hairspray, oils, or gels. Do not come in with wet hair. Eat normal meals and take medications as usual. No caffeine beverages.

Four disc electrodes are applied to the patients head and a hearing test is first conducted. When the test starts, the patient will hear clicking in the left ear and a fuzzy noise in the right ear. The clicks are the stimulus to the Auditory Nerve which runs from the outer ear, inner ear, lower brainstem, upper brainstem, then travels to the temporal region of the brain. This information will be displayed on the computer screen as waves. After the test is complete, the results will be evaluated for abnormalities.

All the patient needs to do is close their eyes and relax during the test. The length of the exam is about 45 minutes. This includes electrode disc application.