Hearing Aid Choices
some special features of hearing aids?
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Hearing aid technology is constantly getting better. Many hearing aids today have special microphones and amplifiers. Many have small digital circuits inside. This technology affects how the hearing aid amplifies sounds. Many choices can be made. One or more of the following options are available:
Wide Dynamic Range Compression
When a hearing aid uses compression, the circuit amplifies or boosts softer sounds more than louder sounds. If a hearing aid circuit has wide dynamic range compression, it automatically adjusts the amount of gain so that soft sounds will be made louder and loud sounds won't be distorted or too loud. This kind of circuit may help children hear conversations at different listening distances.
Some hearing aids have microphone settings that change between omni-directional and directional. Omni-directional microphones pick up sounds coming from all around. Directional microphones pick up sounds from a narrow listening direction. This is like a camera that has a wide-angle and zoom lens.
In noisy listening situations a directional microphone can reduce the loudness of sounds and noise coming from behind. It can help the hearing aid user hear speech that is coming from the front. This can be helpful when listening in noise, but there can be problems when directional microphones are used with young children. Babies and toddlers learn a lot of speech and language by listening to others who are talking around them. This is called overhearing and it is an important part of learning words and language. Directional microphones can reduce how much speech and language is overheard, especially when the child is not looking at the people who are talking.
Safety might be a concern if children cannot hear warning sounds such as traffic when the directional microphone is turned on. It is important that children's hearing aids use a type of directional microphone that can be turned on and off. Parents need to understand what situations are good and bad for using a directional microphone.
Many digital hearing aids can keep more than one listening program stored in the hearing aid circuit. Multiple programs let the hearing aid user choose different microphone or hearing aid settings by using a remote control or program button on the hearing aid. Adults often use different programs for listening in noisy situations or when listening to TV or music. Having the choice of different programs can be good for young children, especially if their hearing fluctuates or changes. This can allow a fast change in the hearing aid settings when parents notice changes in the child's responses. Parents can also use multiple programs when a very young child is fitted with hearing aids. The parents can help the audiologist decide which hearing aid setting provides the best audibility for their child. When using multiple programs, parents need to be in control of the program settings and need to know when to change programs. Parents should work with the audiologist to understand how to use multiple programs
Due to constant improvements in microchips, most new hearing aids have digital circuits. This lets the audiologist make computerized adjustments to many different features. The audiologist uses a computer connection to the hearing aid to adjust the hearing aid response, the listening programs and the type of processing in the hearing aid. This flexibility is helpful when setting hearing aids for babies. When more information about a baby's hearing is available, a digital hearing aid can be adjusted in many ways to provide a good fitting.
FM (Frequency Modulated) systems often are used in school classrooms to help a child hear the teacher better. The teacher wears a small microphone and radio transmitter and the child wears either a radio receiver alone or hearing aids connected to radio receivers. Sound is sent directly between the teacher and the child using wireless radio (FM) signals. FM systems improve listening in difficult situations where a hearing aid alone may not help enough. The most difficult situations are noisy backgrounds, large distances between the speaker and hearing aid user, and rooms with a lot of reverberation or echo.
Many pediatric audiologists now recommend that FM systems be used at home. FM systems can be used with babies and young children to help in places like traveling in the car, playing at the park or going to a museum or zoo. An FM system can help in any situation that has loud background noise and big distances between parents and children because Mom's or Dad's voice is sent directly to the child's hearing aid.