Ask the Audiologist

Auditory Brainstem Response (ABR)

The ABR test is a useful diagnostic tool for measuring hearing when more conventional hearing tests cannot be used.

The ABR test is reliable, objective, noninvasive and painless. Brain wave activity in the auditory centers of the brain is recorded in response to a series of clicks presented to each ear. Thus, the ABR test indirectly estimates the level of hearing in the peripheral auditory system (middle ear and inner ear).

Because of the nature of this testing procedure, the ABR test does not rely on any form of subjective response from the individual being tested. It is virtually unaffected by the use of anesthesia or sedation, or whether the patient is asleep or attentive.

ABR can be used:

  • as a screening procedure for newborns who are at risk for hearing loss.
  • as a diagnostic tool to identify infants and small children with a hearing loss.
  • to estimate hearing levels in difficult to test patients, i.e., mentally retarded, autistic, developmentally delayed.
  • to evaluate patients with suspected retrocochlear pathology.
  • to evaluate patients with Meniere's disease or similar disorders.
  • intra-operative monitoring (Neurological patients).
  • as a prognostic indicator for patients with head trauma.

Test Procedure:
The ABR test is performed on an individual who is resting quietly or in a sleep state. Mild sedation may be used, when necessary, under a physician's supervision. A series of clicks are presented to each ear through special earpieces inserted into the ear canals. The audiologist can vary the intensity of the clicks. The individual wears a headband which records appropriate brain wave activity. The averaging computer in the ABR unit then analyzes the information and it is compared to normal responses. This procedure does not cause any discomfort to the person. The test takes approximately one to two hours.