Auditory Brainstem Response (ABR) Test
This is one of many tests that may be recommended for the evaluation of dizziness, balance problems, hearing loss, ear pressure and/or tinnitus (ear noise). The ABR determines how well the auditory nerve is transmitting sound (in the form of electrical impulses) from the inner ear to the brainstem. Specifically, the test helps to determine whether or not there is a blockage in the transmission of electrical signals to the brain. A small percentage of patients may have benign growths on the nerve leading from the ear to the brain (acoustic neuroma). This test can help determine if such a benign growth is present or if your symptoms are due to other causes.
Clicks of varying speeds are used to stress the system and verify the auditory nerve’s ability to handle rapid stimulation. This test can also be used to test hearing in patients not able to do a traditional hearing test in the sound booth (for example infants), determining degree of hearing loss: mild, moderate, severe, or profound.
An ABR test is administered by placing electrodes in your ear canal or behind your ear and on your forehead. A clicking noise is then presented to each ear individually. This test is done in a darkened room and you lay as still and relaxed as possible. Testing takes from 15 minutes to one hour depending on how many things are being assessed.