Brainstem Auditory Evoked Potential (BAEP) Testing

What is a Brainstem Auditory Evoked Potential (BAEP)?

Brainstem Auditory Evoked Potential (BAEP) testing, like other methods, uses outside stimulus to trigger a response from the brain. The process of stimulation causes electrical signals in the brain known as evoked potential and can be extremely helpful in determining if the auditory nerve is functioning properly.

What does a Brainstem Auditory Evoked Potential (BAEP) diagnose?

A Brainstem Auditory Evoked Potential (BAEP) test may be ordered by your neurologist if you suffer from hearing loss due to poor nerve signaling or conduction. The changes in hearing may not be the same in both ears and can vary in severity. By observing and recording how signals move along the auditory nerve from the cochlea through the brain and brainstem, neurologists can diagnose a wide range of conditions. An auditory nerve that is not functioning properly can be an indication of neurological disorders such as multiple sclerosis, brain or spinal tumors, acoustic neuroma, subarachnoid inflammation and many others. Even if hearing is not completely lost, a Brainstem Auditory Evoked Potential (BAEP) test will detect the abnormality in the response pattern. BAEPs have maximal clinical utility, especially in infant audiological evaluations. Because BAEPs are very non-specific tests, thorough patient history and examination are important for proper diagnosis. 

What to expect during your Brainstem Auditory Evoked Potential (BAEP)

Because Brainstem Auditory Evoked Potential (BAEP) testing is non-invasive, your technologist is able to make sure you are as comfortable as possible and relaxed before starting. During the test, you will want to try and sit relatively still while remaining as quiet as possible. The testing process is typically less than an hour-long, but it is worth noting that dozing off will not adversely affect your results. Once in a comfortable position, the technician will clean areas of the scalp with a cotton ball and use conductive cream to adhere electrodes to particular spots on the scalp or earlobe. The left-over paste rinses out easily and will not dry to your hair. Next, you will be given special headphones to wear as the technician establishes your hearing threshold. This is accomplished by gradually increasing the volume of a clicking noise in the headphones and you signaling when sound is first heard. Once you are ready to begin testing, the technician will turn the stimulus volume up louder in one ear. You will hear the clicking sound for approximately 10 to 15 minutes while the brain responses are recorded. The technician will then switch the stimulus to the opposite ear and repeat the same process. Usually, each stimulus is repeated a number of times to ensure plenty of responses are recorded for an appropriate average.

How to prepare for a Brainstem Auditory Evoked Potential (BAEP)

Because getting clear test results is of the utmost importance, there are a few steps you should take to prepare for a Brainstem Auditory Evoked Potential (BAEP) test that will increase the chances of having accurate readings. If you regularly use hearing aids or have obvious hearing problems, you should let the technician know before starting the test as proper accommodations may need to be made. Also important, washing your hair the night before and avoiding all chemicals, oils, and lotions for at least 24 hours in advance ensures that the conductive cream used to adhere electrodes to the scalp will create strong connections. If you currently take any medication, you should continue to do so on the day of the test. You should also eat and drink as you normally would, as these factors will not influence test results.

Have more questions? Feel free to contact your local Brain and Spine Specialists office to learn more about your upcoming Brainstem Auditory Evoked Potential (BAEP).