Hearing Tests for Children

What are hearing tests for children?

Hearing tests measure how well your baby or child can hear different sounds. These tests can differ depending on the child's age. For example, an older child may have the same type of hearing tests as those used for adults. These types are called audiometry tests, and they include pure-tone and speech tests. In these types, your child will respond to the tones or words they hear.

Hearing depends on a series of steps that change sound waves into electrical signals that the brain understands as sounds. Hearing loss happens when there's a problem with any of these steps:

• Sound waves enter the outer ear and travel to the eardrum in the middle ear.
• The soundwaves vibrate the eardrum, which sends the vibrations to tiny bones that make the vibrations stronger.
• The vibrating bones make tiny waves in the fluid that's inside the cochlea. The cochlea is a snail-shaped structure in the inner ear that is lined with hair-shaped sensory cells. When the hair cells move with the fluid waves, they create electrical signals.
• The auditory (hearing) nerve carries the electrical signals from the inner ear to the brain, which turns them into sounds you can recognize and understand.

Your child's provider can use certain tests that don't require a baby's cooperation to see if any part of this process isn't working the way it should. These tests include:

• Auditory brainstem (ABR) tests, which use electrodes to check how well the inner ear, the hearing nerve, and parts of the brain respond to sounds
• Otoacoustic emissions (OAE) tests, which use small devices to check for damage in the cochlea's hair cells
• Tympanometry, which checks how well the eardrum and bones in the middle ear are working
• Acoustic reflex measures (also called middle ear muscle reflex, or MEMR, test), which use a small device to see how well a muscle in the middle-ear responds to loud sounds
• Auditory steady-state response (ASSR), which is a newer method similar to an ABR test that can tell if there are any pitches of sound your child struggles to hear

Other names: audiometry; audiography, audiogram, sound test

What are they used for?

Hearing tests for children are used to screen for, diagnose, and monitor hearing loss. To screen for hearing loss, your child's provider may use OAE and ABR tests. However, these tests can't diagnose anything on their own. They can only show if your child needs more testing.

If they don't pass a screening test, or if you have concerns about your child's hearing, more complete tests can diagnose hearing problems. To make a diagnosis, your child's provider may use a combination of tests including OAE, ABR, tympanometry, and acoustic reflex measures tests.

There are three main types of hearing loss:

• Conductive hearing loss happens when sound waves can't reach the inner ear. Earwax or abnormal fluid in the ear may be blocking the path, or a hole in the eardrum may prevent it from vibrating. Ear infections are a common cause of this type of hearing loss in infants and young children. Medical treatment or surgery can often improve hearing.
• Sensorineural hearing loss (also called nerve deafness) happens when there's damage to the cochlea in the inner ear or the auditory nerve. This type of hearing loss ranges from mild (difficulty hearing certain sounds) to profound (not hearing any sound). The hearing loss is usually permanent, but it can improve with hearing aids or other devices.
• Mixed hearing loss is a combination of both sensorineural and conductive hearing loss.

One type of sensorineural hearing loss is called auditory neuropathy spectrum disorder (ANSD). With ANSD, there's a problem with how the inner ear or the hearing nerve sends sound to the brain. This type of hearing disorder may happen if your child has health problems before or during birth or as a newborn. These problems include premature birth (being born too soon), low birth weight, and jaundice. ANSD may also be caused by a genetic disorder.

It is important to check for hearing loss in babies and children as soon as possible. That's because hearing loss can delay a child's ability to talk, understand spoken language, and develop social skills. If it's found early, your child's provider can treat the problem and recommend ways to help your child learn language skills.

Your child's provider can also use hearing tests to:

• Determine how severe the hearing loss is
• Find out whether hearing loss affects one ear or both ears
• Help determine which parts of the ear are involved
• Check children who have risk factors for hearing loss
• See if there are any changes in your child's hearing over time
• Help guide treatment and support for a child with hearing loss

Why does my child need a hearing test?

Routine hearing screening tests are recommended for all babies and children:

• Newborns should have a screening test for hearing problems by 1 month of age. If you give birth in a hospital, the screening test is usually done before your baby goes home. If you give birth at home, make sure to talk to your baby's provider about testing. Children should have their hearing checked before they enter school. Once in school, children may also have hearing screening tests as part of their regular health checkups.

More complete hearing tests are needed any time there is a concern about your child's hearing:

• If your baby doesn't pass the newborn hearing screening test, your baby will need complete hearing tests before they reach 3 months of age.
• If your baby passes the newborn hearing screening test, but has a high risk for developing hearing loss, your baby will need complete hearing tests between 24 and 30 months of age. These risk factors include ear infections and a family history of childhood hearing loss. Ask your baby's provider about your baby's risk level.
• If your baby or child shows signs of hearing loss, contact your child's provider as soon as possible.

Signs of hearing loss in a baby include:

• Not being startled by loud noises
• After 6 months of age, not turning toward a sound
• By 12 months of age, not saying simple words, such as “dada” or “mama”

Signs of hearing loss in children include:

• Unclear speech
• Not following directions
• Often saying “Huh?” or “What?”
• Turning the TV volume up too high
• Learning problems

What happens during a hearing test?

Which hearing tests your child's provider uses will depend on your child's age and ability to follow instructions.

Hearing screening tests for newborns, infants, and very young children can measure hearing without needing your child to cooperate. These tests can even be done while your child sleeps. The two most used types are auditory brainstem (ABR) and otoacoustic emissions (OAE) tests.

During an ABR test:

• The provider will place electrodes (small sensors that stick to the skin) on the scalp. The electrodes are connected to a computer.
• Tiny, soft earphones will be placed inside the ears.
• The earphones will play sounds.
• The electrodes measure how the brain responds to the sounds. The results are shown on the computer.

During an OAE test:

• A small device will be placed in the ear. It can make and measure various sounds.
• The sound from this device makes the fluid in the cochlea ripple, which moves the hair-shaped sensory cells. When the hair cells move, they make vibrations that have their own sound called OAEs.
• The device measures OAEs to see how well the hair cells are working. If the test shows little or no OAEs, your child may have sensorineural hearing loss.

Your child's provider may also use an ASSR test. This type is very similar to an ABR test, except in an ASSR, your child's provider will play sounds with different pitches and levels of loudness.

Hearing screening tests for older children are usually audiometry tests. For these:

• Your child will wear headphones. If your child won't wear headphones, sounds may be played through speakers in a sound booth.
• For a pure-tone test, each time your child hears a tone they will raise their hand, push a button, or say that they heard the sound.
• For a speech test, your child will hear simple words at different levels of loudness. Some words will be spoken over noise. Your child will repeat the words they hear.

Audiometry tests can be adapted for very young children and infants:

• For young children, the tests may include a game to help them pay attention to the sounds. For example, a child may put a block in a box each time they hear a sound.
• For infants and toddlers, the provider will watch for behavior changes that show the child heard a sound. For example, an infant may start sucking a pacifier or look to see where the sound came from. In some tests, a health care professional may show your child a toy as a reward for responding to a sound.

If your child needs more complete hearing tests, they will likely be referred to a hearing specialist, such as:

• A pediatric audiologist, a health care professional who is trained to test hearing, diagnose hearing loss, and provide hearing devices and services to improve hearing in children.
• A pediatric otolaryngologist (ENT), a doctor who specializes in diagnosing and treating ear conditions in children. This type of provider may also be called a pediatric otologist.

During a complete hearing exam, your child may have several types of hearing tests, including tympanometry and acoustic reflex measures tests.

During a tympanometry test:

• A small device will be placed in your child's ear.
• The device will send air and sound into the ear, which makes the eardrum move. Your child will feel the air pressure.
• A machine records the movements of the eardrum on graphs called tympanograms.
• If the eardrum doesn't move normally, your child may have fluid or wax buildup in the ear, a hole in the eardrum, a tumor in the ear, middle ear bones that don't vibrate well, or another problem.

During an acoustic reflex measures test:

• A small device will be placed in your child's ear.
• The device will make loud sounds.
• A machine will show if the sound triggered the ear muscle to tighten. Normally, this muscle tightens to protect your ear when you hear loud noises. If unusually loud noises are needed to trigger the muscle to tighten, or if it doesn't tighten at all, your child may have hearing loss.

Will I need to do anything to prepare for a hearing test?

There are no special preparations for a hearing test. But it's helpful to tell your child what to expect. Let your child know they will hear sounds. If you have a pair of headphones, you might let your child try them on to see what they feel like.

Are there any risks to hearing tests?

There is no risk to having hearing tests.

What do the results mean?

If your child's hearing screening test shows normal hearing, your child usually won't need more hearing tests until their next routine screening. But if you have concerns about your child's hearing or if your child has risks for hearing loss, talk with your child's provider about getting more complete hearing tests.

If the results of complete hearing tests show that your child has hearing loss, the results will also show how severe it is, which ear is affected more, and whether they have conductive, sensorineural, or both types of hearing loss.

• With conductive hearing loss, treatment may be able to restore your child's hearing. The treatment will depend on what's blocking sound from reaching the inner ear. It may include removing wax, draining fluid, or doing surgery to fix problems with the eardrum or ear bones.
• With sensorineural hearing loss, the loss of hearing is permanent. But your child's hearing may improve with hearing aids or surgery to implant a device called a cochlear implant.

Other treatment and support options for hearing loss in children include:

• Working with professionals who can help children and their families learn to communicate. This may include learning sign language, lip reading, or other ways to communicate.
• Education to help your child learn communication skills.
• Assistive devices, such as devices for using the telephone and alerting your child to alarms, doorbells, and other sounds.
• Support groups.

Even if a child has had a normal hearing test in the past, new concerns about hearing should be discussed with a provider because some hearing loss can develop later or become worse over time. If you have questions about your child's hearing and treatment, talk with your child's primary care provider or hearing specialist.

Learn more about laboratory tests, reference ranges, and understanding results.