Download lessersoundapp-Share and Enjoy!
A hearing aid is a small electronic device that you wear in or behind your ear. It makes some sounds louder so that a person with hearing loss can listen, communicate, and participate more fully in daily activities. A hearing aid can help people hear more in both quiet and noisy situations. However, only about one out of five people who would benefit from a hearing aid actually uses one.
A hearing aid has three basic parts: a microphone, amplifier, and speaker. The hearing aid receives sound through a microphone, which converts the sound waves to electrical signals and sends them to an amplifier. The amplifier increases the power of the signals and then sends them to the ear through a speaker.
Hearing aids are primarily useful in improving the hearing and speech comprehension of people who have hearing loss that results from damage to the small sensory cells in the inner ear, called hair cells. This type of hearing loss is called sensorineural hearing loss. The damage can occur as a result of disease, aging, or injury from noise or certain medicines.
A hearing aid magnifies sound vibrations entering the ear. Surviving hair cells detect the larger vibrations and convert them into neural signals that are passed along to the brain. The greater the damage to a person’s hair cells, the more severe the hearing loss, and the greater the hearing aid amplification needed to make up the difference. However, there are practical limits to the amount of amplification a hearing aid can provide. In addition, if the inner ear is too damaged, even large vibrations will not be converted into neural signals. In this situation, a hearing aid would be ineffective.
If you think you might have hearing loss and could benefit from a hearing aid, visit your physician, who may refer you to an otolaryngologist or audiologist. An otolaryngologist is a physician who specializes in ear, nose, and throat disorders and will investigate the cause of the hearing loss. An audiologist is a hearing health professional who identifies and measures hearing loss and will perform a hearing test to assess the type and degree of loss.
Behind-the-ear (BTE) hearing aids consist of a hard plastic case worn behind the ear and connected to a plastic earmold that fits inside the outer ear. The electronic parts are held in the case behind the ear. Sound travels from the hearing aid through the earmold and into the ear. BTE aids are used by people of all ages for mild to profound hearing loss.A new kind of BTE aid is an open-fit hearing aid. Small, open-fit aids fit behind the ear completely, with only a narrow tube inserted into the ear canal, enabling the canal to remain open. For this reason, open-fit hearing aids may be a good choice for people who experience a buildup of earwax, since this type of aid is less likely to be damaged by such substances. In addition, some people may prefer the open-fit hearing aid because their perception of their voice does not sound “plugged up.”
In-the-ear (ITE) hearing aids fit completely inside the outer ear and are used for mild to severe hearing loss. The case holding the electronic components is made of hard plastic. Some ITE aids may have certain added features installed, such as a telecoil. A telecoil is a small magnetic coil that allows users to receive sound through the circuitry of the hearing aid, rather than through its microphone. This makes it easier to hear conversations over the telephone. A telecoil also helps people hear in public facilities that have installed special sound systems, called induction loop systems. Induction loop systems can be found in many churches, schools, airports, and auditoriums. ITE aids usually are not worn by young children because the casings need to be replaced often as the ear grows.
Canal aids fit into the ear canal and are available in two styles. The in-the-canal (ITC) hearing aid is made to fit the size and shape of a person’s ear canal. A completely-in-canal (CIC) hearing aid is nearly hidden in the ear canal. Both types are used for mild to moderately severe hearing loss.Because they are small, canal aids may be difficult for a person to adjust and remove. In addition, canal aids have less space available for batteries and additional devices, such as a telecoil. They usually are not recommended for young children or for people with severe to profound hearing loss because their reduced size limits their power and volume.
The hearing aid that will work best for you depends on the kind and severity of your hearing loss. If you have a hearing loss in both of your ears, two hearing aids are generally recommended because two aids provide a more natural signal to the brain. Hearing in both ears also will help you understand speech and locate where the sound is coming from.
You and your audiologist should select a hearing aid that best suits your needs and lifestyle. Price is also a key consideration because hearing aids range from hundreds to several thousand dollars. Similar to other equipment purchases, style and features affect cost. However, don’t use price alone to determine the best hearing aid for you. Just because one hearing aid is more expensive than another does not necessarily mean that it will better suit your needs.
A hearing aid will not restore your normal hearing. With practice, however, a hearing aid will increase your awareness of sounds and their sources. You will want to wear your hearing aid regularly, so select one that is convenient and easy for you to use. Other features to consider include parts or services covered by the warranty, estimated schedule and costs for maintenance and repair, options and upgrade opportunities, and the hearing aid company’s reputation for quality and customer service.
- What features would be most useful to me?
- What is the total cost of the hearing aid? Do the benefits of newer technologies outweigh the higher costs?
- Is there a trial period to test the hearing aids? (Most manufacturers allow a 30- to 60-day trial period during which aids can be returned for a refund.) What fees are nonrefundable if the aids are returned after the trial period?
- How long is the warranty? Can it be extended? Does the warranty cover future maintenance and repairs?
- Can the audiologist make adjustments and provide servicing and minor repairs? Will loaner aids be provided when repairs are needed?
- What instruction does the audiologist provide?
- My hearing aid feels uncomfortable. Some individuals may find a hearing aid to be slightly uncomfortable at first. Ask your audiologist how long you should wear your hearing aid while you are adjusting to it.
- My voice sounds too loud. The “plugged-up” sensation that causes a hearing aid user’s voice to sound louder inside the head is called the occlusion effect, and it is very common for new hearing aid users. Check with your audiologist to see if a correction is possible. Most individuals get used to this effect over time.
- I get feedback from my hearing aid. A whistling sound can be caused by a hearing aid that does not fit or work well or is clogged by earwax or fluid. See your audiologist for adjustments.
- I hear background noise. A hearing aid does not completely separate the sounds you want to hear from the ones you do not want to hear. Sometimes, however, the hearing aid may need to be adjusted. Talk with your audiologist.
- I hear a buzzing sound when I use my cell phone. Some people who wear hearing aids or have implanted hearing devices experience problems with the radio frequency interference caused by digital cell phones. Both hearing aids and cell phones are improving, however, so these problems are occurring less often. When you are being fitted for a new hearing aid, take your cell phone with you to see if it will work well with the aid.
- Keep hearing aids away from heat and moisture.
- Clean hearing aids as instructed. Earwax and ear drainage can damage a hearing aid.
- Avoid using hairspray or other hair care products while wearing hearing aids.
- Turn off hearing aids when they are not in use.
- Replace dead batteries immediately.
- Keep replacement batteries and small aids away from children and pets.
Although they work differently than the hearing aids described above, implantable hearing aids are designed to help increase the transmission of sound vibrations entering the inner ear. A middle ear implant (MEI) is a small device attached to one of the bones of the middle ear. Rather than amplifying the sound traveling to the eardrum, an MEI moves these bones directly. Both techniques have the net result of strengthening sound vibrations entering the inner ear so that they can be detected by individuals with sensorineural hearing loss.
A bone-anchored hearing aid (BAHA) is a small device that attaches to the bone behind the ear. The device transmits sound vibrations directly to the inner ear through the skull, bypassing the middle ear. BAHAs are generally used by individuals with middle ear problems or deafness in one ear. Because surgery is required to implant either of these devices, many hearing specialists feel that the benefits may not outweigh the risks.
Hearing aids are generally not covered by health insurance companies, although some do. For eligible children and young adults ages 21 and under, Medicaid will pay for the diagnosis and treatment of hearing loss, including hearing aids, under the Early and Periodic Screening, Diagnostic, and Treatment (EPSDT) service. Also, children may be covered by their state’s early intervention program or State Children’s Health Insurance Program.
Medicare does not cover hearing aids for adults; however, diagnostic evaluations are covered if they are ordered by a physician for the purpose of assisting the physician in developing a treatment plan. Since Medicare has declared the BAHA a prosthetic device and not a hearing aid, Medicare will cover the BAHA if other coverage policies are met.
Some nonprofit organizations provide financial assistance for hearing aids, while others may help provide used or refurbished aids. Contact the National Institute on Deafness and Other Communication Disorders (NIDCD) Information Clearinghouse with questions about organizations that offer financial assistance for hearing aids.
Researchers are looking at ways to apply new signal processing strategies to the design of hearing aids. Signal processing is the method used to modify normal sound waves into amplified sound that is the best possible match to the remaining hearing for a hearing aid user. NIDCD-funded researchers also are studying how hearing aids can enhance speech signals to improve understanding.
In addition, researchers are investigating the use of computer-aided technology to design and manufacture better hearing aids. Researchers also are seeking ways to improve sound transmission and to reduce noise interference, feedback, and the occlusion effect. Additional studies focus on the best ways to select and fit hearing aids in children and other groups whose hearing ability is hard to test.
Another promising research focus is to use lessons learned from animal models to design better microphones for hearing aids. NIDCD-supported scientists are studying the tiny flyOrmia ochracea because its ear structure allows the fly to determine the source of a sound easily. Scientists are using the fly’s ear structure as a model for designing miniature directional microphones for hearing aids. These microphones amplify the sound coming from a particular direction (usually the direction a person is facing), but not the sounds that arrive from other directions. Directional microphones hold great promise for making it easier for people to hear a single conversation, even when surrounded by other noises and voices.
Digital Hearing Aids Vs. Analog Hearing Aids
What’s The Difference?
Learn the differences between digital and analog hearing aids, and you will be more knowledgeable than most people – and more empowered to make a better decision!
True Digital or “DSP” Hearing Aids
A true digital hearing aid (DSP, or digital signal processor) takes the incoming signal from the microphone, converts it into a digital format, and then processes the signal using digital technology before converting it back into an analog sound to be delivered to your ear. Digital hearing aids are normally much more flexible and can be used to process sound more selectively than an analog.
Advantages of DSP
- Certain “noise reduction algorithms” can be programmed into the circuit to help reduce background noise.
- Digital feedback reduction can make more gain available without whistling occurring.
- Some instruments are able to have multiple memories for different listening situations.
- Some instruments select and follow the sound of voices with a self-focusing directional microphone.
- The greatest degree of flexibility in adjustments is available with a good instrument.
Some low priced digital hearing aids have reduced or eliminated most of the benefits above to cut the cost. Just because it is advertised as “digital” does not mean it is a quality product. Sometimes you may experience better sound quality with an analog aid than with a budget digital. A high-end, high quality digital instrument can sound terrible if programmed incorrectly by the fitter. The complexity and flexibility create a steep learning curve to the dispenser. Ask the dispenser how long he has been fitting the aid he is promoting. Don’t be a guinea pig. Just because it is expensive does not mean it is a good hearing aid. Read about different brands on the Internet or in a library. Talk to hearing aid users to find out their experiences.
Analog hearing instruments amplify the sound wave by simply making it larger. They use transistors in a circuit to amplify and modify the incoming sound. Any changes to the sound of the hearing aid are made with the volume control, small trimmers to adjust the response, or by sending the aid back to the manufacturer to have components changed.
Advantages of analog hearing aids
- Long time hearing aid users sometimes find the sound more acceptable because they are used to it.
- Cost is less than digital.
- Are sometimes more powerful than digital.
Programmable hearing aids can have their response (sound) changed in the dispenser’s office rather than sending it back to the factory. If you need more power, a change in frequencies, or other changes, the hearing aid fitter can plug a cord into your hearing aid and modify it on the spot. Some programmable hearing aids are analog, not digital.
Advantages Of Programmable Hearing Aids
- Sound and results can be changed in dispenser’s office.
- Sound can easily be adjusted to better fit your own likes and dislikes.
- Offers the analog circuitry with some of the flexibility of digital aids.
A digitally programmable hearing aid may still be analog, not digital. The first use of digital technology in hearing aids was to use a digital function to change the sound of the hearing aid. These hearing aids are often still analog hearing aids; they just use digital programming to make changes to the sound. A hearing aid that is truly a digital hearing aid is referred to as “DSP”, for digital signal processing.
Digital Hearing Aid Definitions:
Frequency ranges that can be adjusted individually. A good analogy can be made with a graphic equalizer on your stereo system. When connected to the computer, an digital hearing aid can have different frequency bands of gain adjusted up or down separately, much like you would slide a control on your stereo to increase or decrease levels sound at different frequency ranges. An entry-level digital may only have one or two bands, which can be adjusted separately, whereas a more adjustable instrument may have 4, 9, 10, 12, or even 16 adjustable frequency bands.
Similar to bands, except that channels are frequency ranges in which compression settings, can be adjusted individually. A person may have a sensitivity to loud high pitched sounds, for instance, and the hearing professional may choose to use more compression in the high frequency channel to provide comfort in that frequency range without having to compress sounds in other ranges of speech.
When a loud, high pitch sound occurs, such as paper rustling, or dishes clanging, the compression will kick in and reduce the amount of amplification in that particular channel.
Each memory of a multi-memory hearing aid can be programmed independently to function for its specified use. You change between memories by pressing a button on the aid, using a remote control or a magnetic wand. Typically one memory will be for normal conversation or television in a quiet setting and one memory will be programmed for noise reduction. Other choices would be telephone usage and music memories. Typically multi-memory hearing aids will have two, three, or four memories.