We may use a combination of behavioral and physiologic measures to assess the hearing/auditory status of infants and children.
- Behavioral hearing tests include behavioral observation, visual reinforcement, conditioned orientation response, conditioned play, and conventional audiometry, as well as speech audiometry.
- Physiologic auditory tests include acoustic immittance measures (for example, tympanometry, acoustic reflexes), Auditory Brainstem Response (ABR – including sedated and unsedated/infant ABR for hearing threshold assessment), and Otoacoustic emissions (OAE).
Please note: At this time, the Pediatric Audiology Program does not offer auditory processing evaluations. Please contact us to find a center that offers this specialized testing.
Behavioral hearing tests
During behavioral hearing tests, the child (and typically the parent) is seated in a sound booth. Sounds of varying intensity are presented to the child via calibrated speakers or earphones. The sounds may consist of speech or music as well as specific frequencies that are critical to access (hear) the different sounds of speech. The audiologist looks for and records the child's responses to the softest sounds presented and plots them out on a graph called an audiogram.
Behavioral hearing tests include the following methods for the following developmental ages:
| Test Method | Age (developmental) |
|---|---|
|
Behavioral Observation Audiometry (BOA) - The child's responses may consist of quieting, eye widening, startle, etc. |
0 to 5 months |
|
Visual Reinforcement Audiometry (VRA) - The child turns to the sound stimulus and a puppet lights-up to reward (reinforce) the child's listening behavior. |
6 months to 2+ years |
|
Conditioned Orientation Reflex (COR) Audiometry - This test is the same as VRA, but multiple sound sources and puppet reinforcers are used. Many parents describe it as a "sound finding game." |
6 months to 2+ years |
|
Conditioned Play Audiometry (CPA) - A listening game that uses toys to maintain the child's attention and focus to the listening task. For example, the child holds a block, waits and listens for the sound. When the child hears the sound, they drop the block in a bucket. This is no different than raising one's hand in response to the sound, but the toys establish and maintains the child interested in the listening task for much longer than hand-raising alone. This "listening game" is demonstrated to the child by the audiologist, and once the child understands the game testing is underway. |
2+ years |
|
Conventional Audiometry - The child raises hand or provides verbal response (for example, "beep", "I hear it") in response to the sound stimulus. |
4 to 5 years |
Physiologic auditory tests
Physiologic auditory tests are not direct measures of hearing. Instead, they measure auditory function. Some of these tests, however, are correlated with difference degrees of hearing or hearing loss.
- Tympanometry (tympanogram) - This type of acoustic immittance test assesses the health of the middle ear system and takes about three to five seconds. A small probe tip is placed in the ear canal. Sound is presented and recorded. A computer plots the movement of the eardrum by measuring the amount of sound reflected back. It is not painful, but does feel a little stuffy for a few seconds.
- Acoustic reflexes - Another type of acoustic immittance test, this test assesses the integrity of a neural loop from the inner ear to the brainstem and back to the middle ear system. The same probe tip assembly is used in this test as is used in tympanometry.
- Otoacoustic emission (OAE) - This test assesses the outer hair cell function in the inner ear (cochlea). It takes about three minutes per run. A probe tip is placed in the ear canal. Sounds are presented and an elicited response recorded. The response is very faint so the child must be extremely quiet during the test. Because the response is so faint, it may be obscured by the presence of ear wax, middle ear pathology (for example, fluid, pressure) or the presence of pressure equalization (PE) tubes.
- Auditory Brainstem Response (ABR) - This is an electrophysiological test. It is used in two ways: to assess auditory nerve function and to estimate hearing levels. Sounds are presented through an earphone while three small surface electrodes (one on or behind each ear and one usually placed on the forehead) pick up the response to sound from the inner ear (cochlea) and auditory nerve. A computer averages the auditory responses and the audiologist interprets the results. Usually, the results are shared with the family immediately following the test. The test is not uncomfortable to the patient.
When this test is used to estimate hearing levels for children six months and older, sedation is required for ABR recording. Sedation is not used for infants from birth through age six months. Sedation is determined and monitored by the PainFree Program anesthesia team. On the day of the ABR test, the child is also seen by the otolaryngology (ear, nose, and throat) staff to determine if the ears are "clear" (for example, free of wax, middle ear fluid/infection) just prior to testing.
If you have questions regarding ABR testing at our center, please contact the Pediatric Audiology Program. If your child is scheduled for a sedated ABR and you have questions regarding sedation, please contact the PainFree Program.