Two different types of hearing screening tests are used to screen hearing in babies
Otoacoustic Emissions-One of the tests is called otoacoustic emissions or OAEs. For this test, a miniature earphone and microphone are placed in the ear, sounds are played and a response is measured. If a baby hears normally, an echo is reflected back into the ear canal and is measured by the microphone. When a baby has a hearing loss, no echo can be measured on the OAE test.
Auditory Brainstem Response-The second test is called the auditory brainstem response or ABR. For this test, sounds are played to the baby's ears. Band-aid like electrodes are placed on the baby's head to detect responses. This test measures how the hearing nerve responds to sounds and can identify babies who have a hearing loss