Childen's Hospital Boston 300 Longwood Avenue
Boston, MA 02115
(617) 355-6000
X
My Child Has:
Auditory Brainstem Response Evaluation
Programs that perform this test
Diagnostic Audiology Program  
What is an Auditory Brainstem Response Evaluation (ABR)?
An Auditory Brainstem Response Evaluation (ABR) is a type of test, usually performed for infants and young children, that evaluates how well sounds travel along the hearing nerve pathways from the ear to the brainstem. There are two main types of hearing loss:
  • Conductive hearing loss -- problems transmitting sound from the outer ear (where sound is collected) to the inner ear. This type of hearing loss can often reverse itself as children grow older.
  • Sensorineural hearing loss -- problems with the nerves connecting the inner ear to the brain. In the inner ear, tiny hairs on the cochlea act as a neural pathway, transmitting through the inner ear. Usually, problems with these hairs on the cochlea are responsible for sensorineural hearing loss. It is usually permanent and present at birth.
An ABR test, by evaluating the hearing nerve pathways, can identify cases of sensorineural hearing loss. It is a sleep EEG hearing test which shows the softest sounds your child's ears can detect at various pitches. The ABR compares changes in brain activity to the timing of repetitive sounds to determine whether the particular intensity of sound can be heard.
How is it performed?
There will be three or four small stickers on your child's head, connected to leads going into a computer. Sounds will be presented through an earphone to each ear separately while a computer analyzes the changes in the brain wave pattern in response to sounds.

Your child should be sleeping for the duration of the test. Young children under the age of six months are not usually sedated, and the test is performed while the infant is naturally sleeping, following a feeding. Children over the age of six months are usually sedated with chloral hydrate.

The test is not painful or uncomfortable in any way, but it is necessary for your child to be asleep in order to obtain clear recordings during the test.

You will be in the room with your child during the test, and the results will be explained immediately afterward.

How long does an ABR test take?
ABR evaluations, both sedated and unsedated, take approximately 2-3 hours to complete.

Important:

Please follow these feeding instructions before your child's ABR test.

Under 6 months of age:

  • No solid food, milk, or formula for 4 hours before the test.
6 months or older:
  • No solid food, milk, or formula for 6 hours before the test.
For all children:
  • Clear liquids such as water, breast milk, or apple juice should be given until 2 hours before the test.
  • Please bring your child awake but very sleepy.
X
X The information on this website should not be taken as medical advice,
which can only be given to you by your personal health care professional.
X
X Copyright © Children's Hospital Boston. All rights reserved.