About Hearing Aids
Hearing aids are devices designed to amplify or make sounds louder. Hearing aids come in a variety of types and brands, and their specifications are determined and set to meet the needs of each individual user. Hearing aids make sounds louder, but do not always make sounds clear. Hearing aids do not fix sound distortions as glasses correct vision. Depending on a student's hearing levels and the degree of distortion in his or her hearing system, a hearing aid will provide different levels of benefit. Think of a radio set between stations--you can make the sound louder, but that does not help you understand what is being transmitted.
Levels of Benefit from a Hearing Aid
Do not expect a hearing aid to correct a student's hearing. Each person obtains a unique degree of benefit, satisfaction, and improvement in life quality through a hearing aid. It is important to communicate with professionals familiar with this area of a child’s development (i.e. audiologist, speech-language pathologist, teacher, etc…) to learn about an individual’s level of benefit from a hearing aid.
Possible levels of benefit from a hearing aid(s) include:
- awareness of sounds for environmental safety (i.e., awareness of car horn, knock on door);
- ability to differentiate between sounds (without the ability to identify what those sounds are);
- identification of changes in rhythm, intensity, intonation, and rate of speech to know whether the person is talking quickly or loudly, is happy, is asking a question, or other affective information;
- ability to monitor one's own voice;
- ability to use sound to assist in producing individual speech sounds;
- recognition of a few words when the context of the message and possible choices of what will be said are very limited (i.e., can understand the command, "get your book" when appropriate in the classroom, or when the choices are limited to "get your book," "get the pencil," or "get your coat");
- recognition of increasing numbers of words and greater detail in sentences;
- comprehension of most of what is said in an ideal listening environment (i.e., quiet, face-to-face);
- comprehension of most conversations, even in adverse listening conditions.
Listening Conditions that Affect the Benefits of Hearing Aids
The benefit an individual obtains from a hearing aid is related to a variety of factors. It is important to take the following factors into consideration related to hearing aids:
- Distance: The benefit of a hearing aid is directly influenced by distance. The farther away the source of the sound, the more difficult it will be for an individual to hear.
- Background noise and reverberation: Hearing aids amplify noises in the environment (i.e., chairs moving, people coughing, and paper rustling), in addition to speech. This makes it difficult for individuals with hearing aids to listen in noisy environments such as a classroom. Reverberation (sound reflecting off hard surfaces such as walls and windows) also negatively impacts the ability to hear with a hearing aid.
- Talking louder does not enhance listening through a hearing aid: A hearing aid needs to do its own work. Talking louder can just push the hearing aid to its limit and cause it to not work effectively.
How to Check a Hearing Aid
For children who use hearing aids, it is necessary to check the aids on a regular basis to ensure proper functioning. This is essential because a hearing aid will only provide benefit if it has a good battery and is working appropriately. With minimal effort and a few minutes a day, teachers and/or parents can learn to check hearing aids. Children of all ages can take varying degrees of responsibility in this process. Even young children can look at their earmolds to see if they are clean and can check to make sure the hearing aid is set to the correct volume.
Note: While the following information describes how to check a hearing aid, it is also important to do a similar check with children who are using cochlear implants. The steps in checking a cochlear implant are in many ways similar, but other ways different, than checking a hearing aid. The child’s audiologist should be able to guide through the unique aspects of troubleshooting a cochlear implant.
At school, a chart is a good way to gather basic information about each student's hearing aid, including brand and model, internal settings, recommended volume, and battery type. This information can be obtained from the child's audiologist and is usually documented in a child's audiological report. Settings and volume can change, so be sure to review the most current assessment available. An audiologist or teacher of deaf students can train individuals within the school to check hearing aids. This chart can also be used to document if the hearing aid is working appropriately following a daily hearing aid check.
In checking a hearing aid, it is important to do both a physical check of the equipment and a check of how the child is functioning with the equipment.
Physical check: Do a visual check of the hearing aid to see if there is any damage to the casing or earmold. Check the battery with an inexpensive battery tester. Only batteries at full power provide good hearing aid function. Listen to the quality of sound of the hearing aid through use of a specially designed hearing aid listening stethoscope. Listen to the hearing aids for any of the following problems:
- Does the sound cut on and off when you change the volume? Is the sound quality clear or is it distorted or very soft?
- Does the quality change as you increase the volume of the hearing aid?
Functional check: It is also important to check a student's performance with their hearing aid in place on a daily basis. First, check that there is no feedback (squealing/whistling) from the hearing aid when it is in place on the child and set at the recommended volume. Next, it is important to complete a listening check with the hearing aid to make sure the child is functioning as expected with the hearing aid.
Checking for feedback: Feedback may indicate that sound is not being transmitted to the child at the recommended level. Feedback may be caused by such things as ear wax, the earmold falling out of place, or the volume inadvertently being set too loud. These things are easy to remedy. Ongoing feedback may suggest the earmold is cracked or too small, and may need to be remade. If this is not the cause, then there is likely another problem with the hearing aid which needs to be checked by an audiologist. To troubleshoot related to feedback, include the following:
- check to see if the earmold fits properly. If it looks too small, inform the student's family or the audiologist so it can be remade. Typically, ear molds need to be remade annually or more frequently for very young children.
- check to see whether there is ear wax in the ear. This can be removed in the doctor's office by a nurse or a nurse's assistant.
- check the volume and turn it down to the appropriate setting. If it still squeals, the mold is too small or there is an internal problem in the aid. Have it checked by an audiologist.
- check for loose tubing or for cracks in the tubing where it attaches to the aid or mold. The audiologist can easily replace the tubing.
Listening Check: One such check, the Ling six-sound test, involves presenting a series of specific speech sounds at a consistent loudness and distance from the student to document his or her sound awareness. It is necessary to obtain a baseline related to whether or not a student is aware of each of these sounds and then check daily for possible changes in functioning. If hearing deviates from the student's baseline, check the aid more carefully. If a thorough check of the aid confirms that it is working well, poor performance on the six-sound test may indicate a problem outside of the hearing aid such as wax buildup, fluid in the middle ear, or a decrease in hearing levels. Inform a student's family when a concern is noted.
To perform the Ling six-sound test, have the student sit at a distance of about three feet wearing his or her hearing aid(s).
1. Cover your mouth with a listening hoop (a specially designed barrier to conceal your mouth while presenting sound without distortion). This hoop can either be bought or homemade.
2. Individually present each of the following six sounds: "mm," "oo," "ah," "ee," "sh," and "s." (These sounds represent the variety of the frequencies present in speech.)
3. Have the child respond (i.e., raise a hand, place a block into a container) when he or she hears a sound. (Note: This task can only be completed after a child is old enough to produce a conscious response to sound. This skill usually emerges at the developmental age of 18 months to 2 ½ years.)
4. Be sure to vary the pause time between sound presentations. Children readily pick up on a pattern and false positive responses will occur. Occasionally intersperse "no sound" during the check to see if the child is responding appropriately; that is, signal the child to listen, hold up the listening hoop, and then say nothing. A child needs to feel confident saying that nothing is heard.
Special considerations when checking a cochlear implant: Present each sound at a very quiet level instead of at a conversational listening level. This will allow for quick identification of changes in the programming of the cochlear implant.
For further resources on hearing aids see: