With a Hearing Aid, a Hearing-Impaired Child Can Hear as Well as You - False!
Unless you yourself have a hearing loss, the only kind of hearing loss you can probably identify with is the kind that can occur when you get a cold, and that's a conductive loss. You may wrongly assume that hearing aids will "fix" the problem and don't use techniques that can make communication better for a person wearing hearing aids. Hearing aids cannot fix the hearing of someone with a sensorineural hearing loss, especially a child.
Hearing aids can make sounds louder, but cannot make them clearer. Listening through a
hearing aid has been described as tuning a radio slightly off a radio station,
allowing static, then making it louder.
Just as with a hearing aid, as the radio plays louder, the static and noise become worse.
You should have been able to easily read the word in the center. This is how a
hearing aid works for a conductive hearing loss: once sound is loud enough (bigger) it can
Could you read the word in the center? This is the way hearing aids work for
sensorineural loss. Even though the aid makes sounds louder, it does not fill in parts of
the sound that are missing or distorted. How much of the word is missing
can be affected by things such as condition of the inner ear,
auditory fatigue , listening experiences,
prior exposure to the word, condition of the earmold, condition of the hearing
aid, and background noise.
We hope this demonstration has helped you understand why it is important to become familiar with and use strategies that will help a hearing-impaired child understand what is being said. You'll find links to many pages on techniques that can help communication on our Teaching & Education Resources page.
Because you've asked for it, lets continue this discussion and take a look at what FM Systems can do for a child who wears hearing aids. Because hearing aids amplify all of the sounds that reach the microphone, noisy environments are difficult for a hearing aid wearer. For those of us who have normal hearing, our brains are able to filter out many of the noises we hear so we don't realize all of the sounds the hearing aids are picking up and amplifying. The best real life example is if you've ever tried to tape record a lecture or class. Have you ever noticed all the noises the mic picked up - yet you were hardly aware of them at the time? How hard did you have to concentrate to be able to hear the main speaker? This is sort of what happens to those wearing hearing aids. But lets put this in a graphic format so we can see what's going on. We'll be using images for a conductive hearing loss in this discussion so please keep in mind that things will be even less clear for a person with a sensorineural hearing loss.
The signal a child is receiving in a typical classroom - even if we don't perceive all of the background noises - can look like this:
Which word came from the teacher or primary speaker and which words came from conversations going on around the child? Even if I tell you it's one of the 2 horizontal words, you can see that other words can be overlapping, making it difficult to decipher the word without some guesswork. This is where FM systems are making a difference for those who wear hearing aids and are expected to function in environments with background noise.
FM systems can help in one of 2 ways. Which way it helps depends upon the settings, how it's coupled to the child, and the child's hearing aids. The first effect it can have is to reduce the volume of sound received by the hearing aids to a volume lower than the sound delivered by the primary speaker. If we applied this to the image above, what we get is:
Now you know the word that came from the primary speaker. For some children, this is the preferred result. When this is done, the child is still able to hear what's going on around them and is able to hear language from other children nearby who may be serving as language role-models.
The other effect the FM system can have is to eliminate all background noise and allow only the sound delivered by the primary speaker.
This is much clearer and easier to understand, but you lose the benefits of being able to hear sounds other than that coming from the primary speaker. For some children, this is the preferred result.
More information about FM systems can be found on our Assistive Technology page.
Did you correctly guess the word on the second card? The word is FIRETRUCK.