Navigating Hearing Tests
When your baby is born, they get a hearing screening at the hospital. If they fail, the parent is referred to additional outside tests. Your child make experience hearing issues at anytime so they will also be referred for some additional tests.
The acronyms can be daunting and confusing. Here are some definitions to help you.
ABR (Auditory Brainstem Response)-
According to ASHA, the auditory brainstem response (ABR) test gives information about the inner ear (cochlea) and brain pathways for hearing. This test is also sometimes referred to as auditory evoked potential (AEP). The test can be used with children or others who have a difficult time with conventional behavioral methods of hearing screening. The ABR is also indicated for a person with signs, symptoms, or complaints suggesting a type of hearing loss in the brain or a brain pathway.
The ABR is performed by pasting electrodes on the head—similar to electrodes placed around the heart when an electrocardiogram is run—and recording brain wave activity in response to sound. The person being tested rests quietly or sleeps while the test is performed. No response is necessary. ABR can also be used as a screening test in newborn hearing screening programs. When used as a screening test, only one intensity or loudness level is checked, and the baby either passes or fails the screen.
OAE (Otoacoustic Emissions)
Otoacoustic emissions (OAEs) are sounds given off by the inner ear when the cochlea is stimulated by a sound. When sound stimulates the cochlea, the outer hair cells vibrate. The vibration produces a nearly inaudible sound that echoes back into the middle ear. The sound can be measured with a small probe inserted into the ear canal.
People with normal hearing produce emissions. Those with hearing loss greater than 25–30 decibels (dB) do not produce these very soft sounds. The OAE test is often part of a newborn hearing screening program. This test can detect blockage in the outer ear canal, as well as the presence of middle ear fluid and damage to the outer hair cells in the cochlea.
This is the type most people imagine. The child sits in a soundproof booth with a set of headphones and indicates in some manner when they begin to hear the sound or pitch. How the child lets the audiology know they hear the sound will vary based on the age of the child.
A test done to help determine how the middle ear and eardrum are working. It does not tell if the child is hearing or not, but helps find any changes in pressure in the middle ear. A soft plastic tip is placed near the ear canal and measures eardrum movement when the pressure changes. The test does not hurt but your child will need to remain still.
A speech test is usually done in conjunction with a pure-tone test. An audiologist will record the patient’s ability to hear words spoken at different volume levels, as well as the patient’s ability to repeat back the words.