Auditory Brainstem Response (ABR)
About ABR Testing
Auditory Brainstem Response (ABR) testing assesses hearing sensitivity by measuring each hearing nerve’s response to sounds (clicks). This noninvasive test is performed on babies who do not pass their newborn hearing screening in the hospital.
Early testing is important because if hearing loss is identified, then remediation can begin immediately to off-set the negative effects of speech and language delays. Babies who are fit with hearing aids no later than 6 months of age typically develop speech and language skills that are equivalent to those of their normal-hearing peers.
Testing is conducted by placing three electrodes on a baby: forehead, left earlobe and right earlobe. The electrodes pick-up the very small electrical energy that the hearing nerves give off when the ear hears clicks, which are played through small insert earphones.
These readings are so small that they can only be seen when the baby is still (e.g., asleep). Once they are awake, even small movements give off electrical energy which interferes with being able to obtain a response. In infants up to three months of age, this test can typically be done in the office without sedation. For babies older than three months of age, this test may require sedation/anesthesia in a hospital setting.