What’s involved in testing your child’s hearing?

Hearing loss is a phrase that can carry a lot of weight, and with that a lot of misinformation. Having a hearing loss does’t mean your child is unable to hear completely, or that sounds just aren’t loud enough.

The degree of hearing varies between every child and with that the kind of support or equipment they require. If you suspect your child might have a form of hearing loss but have been putting off a hearing check fearing the worst, now’s the time to act.

The first thing to do is call your GP. They can check for an ear infection or other medical condition. If that’s been ruled out, a hearing test may be in order. There’s no need to panic, the earlier a condition is detected the less impact it will have on their language and communication skills. Early intervention is proven to have positive effects compared to those who choose to act on it later in life.

The tell-tale signs

There are plenty of tell-tale signs that your child might have a form of hearing loss. Your child may:
  • not respond to you/others from a distance
  • be unable to discern words clearly
  • have delays in speech and language development
  • have trouble with educational progress

The impact of hearing loss on a developing child is quite different from the effects of hearing loss that occur in adulthood. Children use their hearing to learn about the world around them and develop communication skills. Any impact on their hearing means those developing skills will also be impacted.

How is hearing tested?

Hearing tests vary depending on a child’s age, ability and overall circumstance. For example, older children usually do a hearing test that checks middle ear function to see whether the ears are congested, as well as a test of how well they can understand speech by listening to words through headphones. Your audiologist will decide which tests are best suited to your child at the time but it will usually involve a combination of behavioural and physiological tests.

Common hearing tests for children

Behavioural tests

  • Behavioural observation audiometry (BOA) is for infants younger than seven months of age and older children who cannot respond when they hear a sound. High, mid and low frequency noisemakers are used and the child’s responses (like startling, or stirring or waking from sleep) are noted.
  • Visual reinforcement orientation audiometry (VROA) is for children between seven months and three years of age. Sounds of various frequencies are played and it is noted when the child turns towards the speaker.
  • Play audiometry for children from three years of age onwards is done to test a child’s hearing when hearing devices are worn. It is similar to pure tone audiometry, except that when the child hears a tone, they put a marble in a marble race, press a computer key or put a piece in a puzzle

Physiological tests

These determine which part of the auditory system is involved in the child’s hearing loss. They measure a physical response of a specific part of the auditory system and require little or no co-operation from the child.

  • Oto-acoustic emission testing (OAE) gives an idea about how hair cells in the cochlea are working. They respond to sound by producing a very soft sound of their own called an oto-acoustic emission.
  • Brainstem evoked response audiometry (BERA) provides information on electrical activity generated in response to sound along the nerve pathway, also called the brainstem, to the brain. It may be carried out while a baby is in natural sleep. If this is not possible, testing must be carried out in hospital.
  • Electro-cochleography (ECochG or EcoG) is performed in hospital, under anaesthetic. It picks up the tiny electrical signals generated in the cochlea in response to sound. It provides information about the functioning of the cochlea and the start of the nerve pathway to the brain.
  • Tympanometry and acoustic reflex give information about the middle ear, which is just behind the eardrum. A tympanogram, which shows if the eardrum is moving normally, may indicate a problem in the middle ear that can cause a conductive hearing loss. When a child has a normal tympanogram, it may be possible to test for the presence of a muscle reflex (the acoustic reflex) in the middle ear. The absence of this reflex to different sounds gives information about the auditory system.

Think your child might need a hearing test? Find your nearest Australian Hearing centre here.