Auditory Brainstem Response (ABR)

ABR testing is available in our Johns Creek office. This test shows us how the inner ear, called the cochlea, and the brain’s pathways for hearing are working.  ABR testing is used most often when there is a significant asymmetry between the ears, typically in high frequencies.  It can provide information about potential hearing loss and is used to diagnose dysfunction of the auditory nervous system.  ABR testing is also used for newborn hearing screenings to obtain ear-specific testing in young children and for those who cannot cooperate with behavioral test methods.

What Happens During ABR Testing?

The ABR is a rate study, measuring how quickly a sound signal reaches the brain on the right side and how quickly it reaches the left.  You will have sticker electrodes placed on your head and behind your ears, on the mastoid bone. The electrodes are connected to a computer that records brain wave activity in response to sounds you hear through earphones. Your job is rest quietly during the test; any type of muscle movement can affect the outcome. Results are provided and reviewed same day.  Infants and young children are routinely sedated for this test to minimize electrical interference caused by muscle movement.

The Results

A normal rate study means both auditory nerves, the right and the left, are performing adequately. This typically concludes that the hearing impairment falls within the cochlea, (not the auditory nerve), and should be treated via hearing devices.  An abnormal rate study is suggestive of an abnormal anatomical condition of the brainstem, preventing the signal from reaching the brain.  At this point, an otologic evaluation with an otolaryngologist (ENT physician) would be recommended to conduct imaging studies of the auditory nerve.  Possible causes for an abnormal ABR are multiple sclerosis, acoustic neuroma, or stroke. Medical management and follow-up would include routine hearing tests to monitor thresholds.