Unlike a hearing evaluation, which evaluates how well you hear sound, an auditory brainstem response test (ABR) evaluates how well the sounds travel along the auditory pathways to a particular part of the brain called the brainstem.
An ABR may be recommended for a variety of reasons. It may be used to estimate the sensitivity of the ear to sound, such as in the testing of newborns or in a child or adult who is unable to accurately complete a hearing evaluation. For adults, the most common reason an ABR is recommended is to help eliminate the possibility of a disorder along the hearing nerve or in the brain itself.
To complete the ABR test, electrodes are pasted and taped to the scalp and earlobes and soft foam tips are inserted into the ear canals. Clicking sounds then are delivered through the ear tips at a comfortable-to-fairly-loud level. These sounds cause nerve responses that are picked up by the electrodes and passed on to sophisticated equipment to record these responses. The audiologist then measures the responses to determine if they are normal or abnormal.