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Hearing Tests for Children with
Multiple or Developmental Disabilities
by Susan Agrawal
Hearing impairment is a common problem in children with developmental disabilities or
who have multiple complex medical issues or disabilities. In many cases, however,
hearing loss is overlooked because of the difficulty of assessing children who cannot
speak, move, follow directions, or maintain concentration throughout a hearing test.
Other disabilities, such as autism or physical disabilities, may make standard indicators of
hearing milestones difficult to interpret for both parents and professionals.
Children with certain congenital or genetic disorders, as well as children with a history of
birth complications, are especially prone to hearing loss. Please see Table 1 for a list of
conditions that are associated with hearing loss. If a child has one or more of these
conditions, a comprehensive hearing screening should be performed. Similarly, any child
who is not meeting age appropriate speech and hearing milestones should be screened for
hearing loss.
Table 1: At Risk Conditions for Hearing Loss1
Family history of hearing loss
In utero infection such as toxoplasmosis, rubella, CMV, herpes, or syphilis
Ear and/or craniofacial differences
High bilirubin levels, especially if exchange transfusion was required
Low birth weight (less than 1500 g)
Bacterial meningitis
Low Apgar scores or birth complications
Respiratory distress at birth
On a ventilator for 10 or more days
Use of a medication such as gentamicin that can cause hearing loss
A genetic condition associated with hearing loss (such as Down
syndrome) or features suggestive of a genetic condition
Persistent or frequent ear infections
Head trauma or fracture
Infectious diseases such as meningitis, mumps, or measles
Neurodegenerative disorders
Brain injury
Failure to meet speech or hearing milestones
Copyright 2011 by Complex Child E-Magazine. All Rights Reserved. This document may be distributed
for educational use only with proper citation.
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Hearing tests for children with developmental or complex disabilities can be difficult to
administer and interpret. The remainder of this article will describe the subjective and
objective tests currently available to assess any child, regardless of disability.
Subjective Testing
Testing for typically developing children over the age of about a year typically involves
subjective hearing testing. Children ages one to four use conditioned or play-based
responses to assess hearing. For example, a preschooler can be taught to place a block in
a jar every time he hears a sound through earphones. A younger child might be trained to
turn and look at a light-up toy when she hears a sound. While imprecise, these screening
tools can provide basic information on hearing loss. A child's attention span and
behavior may limit the ability to obtain valuable results.
Once a typically developing child reaches age four, testing is performed using standard
behavioral audiometry, with the child raising his hand when he hears a sound through
earphones, or in some cases, through bone vibration.
Many children with multiple or developmental disabilities are unable to perform
successfully on these tests. A child with cerebral palsy, for example, may not have the
fine motor skills to lift or drop a block. Or a child with autism may not be able to tolerate
the aural stimuli or respond consistently or appropriately to sounds. Some children with
cognitive deficits may not be able to learn the trained responses they need to give in
response to the aural stimuli. In these and similar other cases, more objective testing is of
value.
Objective Testing
There are several different tests that can be performed on children unable or unwilling to
complete regular audiometry. These include Otoacoustic Emission (OAE) testing,
Auditory Brainstem Response (ABR), and Auditory Steady-State Response (ASSR).
Otoacoustic Emission Testing (OAE)
The inner ear or cochlea actually generates a small sound. In children with healthy ears,
this sound can be evoked by providing a click or tone in the ear, and a small microphone
measures whether the small sound is produced or not. If it does not occur, this suggests
that the middle or inner ear is not functioning appropriately.
This hearing test is valuable because it is simple to do on a child of any age, can be
performed during sleep, is very fast, tests each ear separately, and is objective. A small
probe is placed in the child's ear that uses tones at various frequencies (high and low
sounds) to detect the possibility of hearing loss. A child will receive a report stating
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whether or not he passed or failed each frequency tested in each ear. This test is
commonly performed on all newborns in many states.
There are limitations to this test. It is not effective if the child is moving or crying, and
fluid in the ears will make the results unreliable, as it blocks transmission of the tones or
reception of the OAEs. It only assesses frequency loss, and cannot quantify if a child can
hear soft or loud sounds. Furthermore, it does not detect any cortical hearing issues or
hearing problems that are caused by damage to the nerves transmitting sound to the brain
or the brain's processing areas for sound.
Auditory Brainstem Response (ABR)
An ABR is a more comprehensive test of hearing that uses electrodes on the head to
sense whether sounds travel appropriately through the auditory nerve into the brainstem.
This test requires the child to be still and quiet for about an hour, so children who are too
young to remain quiet are often sedated during the test. Most children between the ages
of about three months and eight years will require sedation. Sleeping infants and older
children without behavioral or developmental issues can be tested without sedation. A
shorter automated type of this test may also be used in newborn screening programs.
During the test, electrodes are placed on the child's head while different tones are played
in each ear. The brain's response to each tone is recorded and allows an audiologist to
determine what frequencies a child can hear (high or low sounds in hertz) and how loud
the sounds must be for the child to hear them (volume in decibels). Some ABR testing,
particularly the abbreviated form used for newborn screening, is automated, but more
comprehensive diagnostic testing requires an audiologist to interpret the brain waveforms
to determine whether a child can hear a particular frequency and volume.
This test does have some limitations. It will not identify cortical processing issues and
cannot be performed accurately if there is fluid in the ears. It is possible to perform the
test using bone conduction (vibration of the bones in the skull) instead of air conduction
(tones in the ear) for children who have persistent problems with fluid or cannot be tested
in the traditional way due to malformations of the ear.
Auditory Steady-State Response (ASSR)
The ASSR is a newer test that is closely related to the ABR and may be performed in
conjunction with it. It also uses electrodes and tones played in the ear, but uses repeated
tones instead of single abrupt tones. It can better identify specific frequency problems,
especially in children with severe or profound hearing loss. It also uses statistical
analysis to interpret brainstem responses instead of relying on an audiologist to interpret
waveforms. This test may provide quicker and more accurate results for children with
significant hearing loss.
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Get Tested!
If your child does not seem to hear you, does not turn to loud sounds, has speech
problems, or has one of the above listed conditions in Table 1, comprehensive testing for
hearing loss is definitely worthwhile. There are many adaptations, ranging from sign
language to hearing aids and cochlear implants, that can improve hearing for many
children. Improving hearing will often help a child make progress in other
developmental domains, including speech, communication, behavior, and learning. Get
your child tested!
1 Adapted from Joint Committee on Infant Hearing. Year 2000 position statement: principles and guidelines for early
hearing detection and intervention. Pediatrics 2000;106:798–817.