Hearing Aid

Introduction to Hearing Aids

Hearing aids, also referred to as hearing instruments, are individual electronic devices powered by a battery, that amplify sounds to help the wearer hear better. The primary goal of a hearing aid is to improve the audibility of speech, and therefore increase communication abilities.

Many people who wear hearing aids and are able to communicate better, report being more socially active, feel an increase of self worth, feel less stress and lead happier, healthier lives. They also make life more pleasant for family members and friends who may show frustration when trying to communicate with someone with hearing loss.

At our office, we determine which is the best instrument based on many factors: 

- The type, degree and severity of hearing loss 
- The lifestyle or social life of the wearer 
- The wearer's cosmetic preference 
- The wearer's physical limitations (ear shape and dexterity abilities) 
- Any medical conditions 
- The amount the wearer is willing to spend 

 Hearing Aids Sizes

There are many different sizes and models of hearing aids, but we will discuss the four most common sizes:

1. Behind-The-Ear (BTE) 
The components of this hearing aid are enclosed in a small plastic case that fits behind the ear. The amplified sound passes through a tube from the BTE to a custom made ear mold placed inside the wearer's ear, which anchors the instrument to the ear and directs the sound towards the ear drum. BTEs offer greater power for those with greater amounts of hearing loss, have larger controls for easier use, and are better for specific types of hearing loss (drainage from the ear, etc.). Children are often fit with BTEs since their ears are still growing. It is easier (and less expensive) to replace the custom made ear mold every year instead of re-making the hearing aid case. This size fits all ranges of hearing loss.

2. In-The-Ear (ITE) 
This is the largest of the custom made hearing aids. All the components are placed within the shell that fits in the outer portion and canal of the ear. This size can fit many types of losses, from mild to severe. This larger custom size (along with the BTE) allows for more space for components or options that can improve hearing in specific listening environments .

3. In-The-Canal (ITC) 
This custom size hearing aid fits in the ear canal and ear canal opening of the wearer. ITCs can only be fit on individuals with a mild to moderately severe hearing loss. It is less visible than the larger sizes and may have smaller controls and a smaller battery, which will not last as long as a larger battery in a larger hearing aid.

4. Completely-In-the-Canal (CIC) 
This tiny custom hearing aid fits entirely in the ear canal of the wearer. Due to the small size, there are no controls that the wearer would be able to manipulate, and the battery size is the smallest of all instruments (lasts about 5 to 7 days). Even though this size is the most cosmetically appealing, there are certain requirements needed by the wearer to take advantage of this size. You have to have a large enough ear canal and only a mild to moderately severe hearing loss. The small wire on the "face" of the instrument is a pull string used to remove the instrument from the ear canal.

There are other custom sizes that typically fall between the sizes listed above. (ex: a mini canal is a size between an ITC and a CIC). Body aids are a wallet sized case that fit in a front pocket with cords that attach to custom ear molds. These aids are less common now than they used to be since BTEs are becoming more and more powerful for more severe or profound losses.


 Hearing Aid Circuit Types

All hearing aids have three important components: a microphone, an amplifier and a speaker (also called a receiver). How the instrument processes incoming sounds is determined by the type of circuit the hearing aid has. Each of these circuits can fit into any of the sizes listed above.

There are three basic categories of circuits.

1. Analog
An analog circuit is a plain, basic processor. We refer to a basic analog circuit as linear, which means "what goes in is what comes out". This is a somewhat simplified description since even analog hearing aids shape incoming signals to maximize speech sounds to some degree. Typically, the appropriate amount of gain or volume for an analog hearing aid is chosen by the manufacturer based on the hearing test results of the wearer. Volume can be controlled by using the volume wheel or dial. An analog hearing aid may have some controls the dispenser can use to change the quality of the sound, like turning up or down low pitched sounds or a reduction of very loud sounds (called compression). These controls are usually very basic filters.

2. Programmable or digitally programmable
A programmable (also called digitally programmable) hearing aid is an analog hearing aid that is connected to the computer by your audiologist or hearing aid dispenser, who then sets the amount of gain or amplification for the hearing aid based on the hearing test entered into the computer. Adjustments can be made to broad "channels", or frequency bands, to adjust the sound quality of the instrument. For example, most programmable instruments have a low frequency or "bass" channel and a high frequency or "treble" channel. Adjustments are made to these channels on the computer to improve the sound quality or fit of the instrument. Programmable instruments also have a user controlled volume control. NOTE: A digitally programmable hearing aid is not an all digital or 100% digital hearing instrument. It is an analog aid that can be adjusted digitally on a computer.

3. Digital
A digital hearing aid allows for even more flexibility than a programmable aid, and offers a clearer, cleaner sound to the wearer. Instead of broad low or high frequency channels, a digital instrument can be adjusted on the audiologist's or dispenser's computer at each frequency (and often at inter-octaves of these frequencies) of an individual's hearing test. This allows for even more precise fittings in relation to an individual hearing loss, giving a more natural, comfortable sound. Digital processing has allowed for more manipulation of incoming signals, allowing some manufacturers to develop special circuits that can reduce constant, steady noises in the environment. These hearing aids cannot eliminate "background" noise (see realistic expectations), but may improve a wearer's chances of understanding speech in the presence of noise. This claim is still in debate between hearing aid manufacturers and the research community. Newer digital models have features that are able to remove feedback (an annoying whistling sound) and reduce the occlusion effect (a plugged up sensation caused by wearing something in your ears). Most digital hearing aids do not have volume controls. They provide the appropriate amount of gain by adjusting to whatever listening environment they are in.

Other hearing aid options that are available in analog and digital instruments include:

Telecoil: A telecoil is a copper coil within the hearing aid that receives the electromagnetic signal of your telephone hand piece. This prevents feedback (a shrill, whistling noise) when placing the phone near the ear or hearing aid. Telecoils are typically only available in the BTE and ITE size, but can be found in some ITC models. The telecoil does not work with cell phones.

Directional microphones (or dual-mics): This option refers to a hearing aid that has two microphones. One microphone amplifies sounds in front of the wearer just like a normal hearing aid would, and a second microphone turns down sounds coming from behind the wearer. This feature is utilized in a noisy room by putting the person you want to speak to in front of you and the noise behind you. Newer digital models incorporate an adaptive directional microphone capable of tracking moving noise sources and adjusting the sound appropriately. Directional microphones are available in the BTE to the ITC sizes.

 One Hearing Aid or Two?

If hearing loss is present in both ears and can benefit from hearing aids, then two (or binaural) hearing aids are recommended instead of one (or monaural). Listed below are the main reasons why a binaural fitting is preferred: 
Studies have shown that some people may lose perception abilities, including the understanding of speech, if the ear is left unaided over a period of time. The brain is programmed to listen with both ears. Wearers of two instruments need less volume than those that wear one, even though they have hearing loss in both ears. Binaural hearing aid wearers have a greater ability to pick out sounds against background noises. 

Binaural hearing aid users report a subjective reduction in communicative effort and more confidence in their responses to questions. Locating where a sound is coming from is improved with binaural hearing aids. Two hearing aids allow for more communication flexibility. For example, a binaural wearer who is driving a car may elect to turn off the left instrument which is receiving the most noise from an open window, and leave the right instrument on to listen to someone in the passenger seat. A person who wears a hearing aid in the left ear only, would have more difficulty in this situation when trying to hear the person in the passenger seat. If you have hearing loss in one ear only, then a binaural fit is not recommended.


 Realistic Expectations

The most common misconception about hearing aids is that they will restore hearing to "normal". For some individuals, it may be possible to obtain normal hearing thresholds through the use of hearing aids, but there are many factors that have to be considered, including (but not limited to): 

- The amount, type and configuration of hearing loss 
- The ability to understand speech, even if it is loud enough to hear 
- The type of technology or circuit chosen for the hearing aid 
- How well the instrument is fit on the individual 

Hearing aids are not able to make distorted sounds appear clear or distinct and may not enable the wearer to hear extremely soft sounds. Hearing sounds through hearing aids is different than the "quality" of sound heard with the ears alone.

Hearing aids do not only amplify the sounds you want to hear. They cannot tell the difference between background sounds and foreground sounds. However, there are some options that may allow for greater understanding in noise (see digital instruments and directional microphones). They may allow the wearer greater speech audibility in noise, but the noise will still be present.

Hearing aids do not "correct" hearing like glasses can correct for vision problems. They are tools to be used to help increase the amount of speech sounds a hearing impaired person would normally miss otherwise.

One thing to keep in mind is that every person's hearing loss is different. The results of someone you know with hearing aids may be completely different than what you may experience if you try hearing aids.


 Taking care of Hearing Aids

Hearing aids can be very delicate and expensive. Keep them away from water or extreme heat or cold. Do not store them in the bathroom, where there is typically high humidity. Keep them out of reach of children and pets (who like to chew on them).

Batteries will need to be changed , depending on the size, power and circuit type of the hearing aid and how often it is used. Batteries can cause serious injury if swallowed or inhaled.

Daily care should involve wiping the aid with a clean, dry cloth. Ear wax and moisture are the main reasons why hearing aids malfunction. It is important to remove all debris according to the manufacturer's instructions that come with the instruments. Never use water or cleaning solutions to clean the instruments. When not using them, the battery door should be left open. This will dry out any moisture inside the aid as well as help the batteries last longer. If there are any problems with the instruments, contact us. Hearing aids have a repair warranty and a loss and damage warranty. The repair warranty covers any repairs in-office or at the manufacturer's repair lab. 

Feel free to contact us if you would like a hearing aid repaired or would like to extend your warranties.

 Adjusting to a New Hearing Aid

Soon after being fit with a hearing aid, the wearer will begin hearing sounds they may not have heard for a long time. Some sounds may sound different or even louder than what they are used to. Their own voice may also sound different to them. These sensations are all common and the wearer will get used to them over time, as long as the hearing aids are working and/or are programmed appropriately. The more the instruments are worn, the sooner the wearer will be comfortable with them.

It is typically recommended to start off using the instruments in quiet one-on-one conversations with family or friends, then gradually try more difficult listening situations (more people, noisier environments). The new hearing aid user will also need to remember to control their listening environment. Since hearing loss typically happens slowly over time, it also takes time to get used to hearing with hearing aids. It is important to have patience and realistic expectations of what the instruments can do. It may take up to six months of consistently using the hearing aids in order to receive the full benefits that they can offer.


 Tips for Better Listening

Control your environment. Position yourself so that you can see the talker well and hear the person most clearly with the least interference from others. Turn on lights or move to a brighter room. Turn off noise sources or move to a quieter room. Favor your better ear if you have one. 

Look at the speaker to ease the strain of listening. Whether you can lip read or not, face the speaker so you can pick up speech cues, body language and facial expressions to help you understand the message better. Be within 10 feet of the speaker. 

Be realistic about your communication abilities. Understand that in very difficult listening environments, you will have problems understanding speech. Anticipate these situations and plan options for dealing with these communication breakdowns. For example, have a friend explain the specials or order for you while in a noisy restaurant. 

Be assertive. Let others know that you have difficulty hearing and encourage them to get your attention before they speak to you. Let them know that short, uncomplicated sentences are easier to understand. Move the conversation away from noise and tell people to slow down or talk louder. Most people will be helpful if you are pleasantly assertive.

Learn communication strategies. If you miss something in a conversation, repeat back what you did understand and have the speaker clarify what you missed. Have the people spell or write down words that you are missing. Begin conversations or be sure you know what the topic of conversation is about. Having people repeat all the time can be embarrassing. Try to do it in an amusing or honest way. For example, say: "I'm going to listen the best I can now, so please say it once more", instead of saying "What?". 

Face the person with hearing loss and make sure your face is in appropriate light so it can be seen easily. Stand within 10 feet and never talk from another room. Keep your hands away from your mouth and avoid using cigarettes, chewing gum or other distracting facial movements. 

Slow, exaggerated speech is just as difficult to understand as fast speech, so keep it at a moderate speed with slight pauses between phrases or sentences. 

Empathize and be patient. Stick both fingers in your ears while having a conversation. You will appreciate the constant challenges a person with hearing loss goes through. Re-phrase to clarify important information. 

Get the listeners attention before speaking. Ask how you can make communication easier. Encourage feedback. 

Control the listening environment. Stand within 10 feet, move away from noise and make sure it is well lighted. Also avoid standing in front of windows, this can "blind" someone trying to see your face. 

Anticipate difficult listening situations and plan strategies in advance. You may have to order food or repeat the specials to the listener in a noisy restaurant.