Hearing Aids - NIDCD
U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of HealthNIDCD Fact Sheet Hearing and BalanceHearing AidsWhat is a hearing aid?A hearing aid is a small electronic device that you wear inor behind your ear. It makes some sounds louder so thata person with hearing loss can listen, communicate, andparticipate more fully in daily activities. A hearing aid canhelp people hear more in both quiet and noisy situations.However, only about one out of five people who wouldbenefit from a hearing aid actually uses one.A hearing aid has three basic parts: a microphone,amplifier, and speaker. The hearing aid receives soundthrough a microphone, which converts the sound wavesto electrical signals and sends them to an amplifier. Theamplifier increases the power of the signals and thensends them to the ear through a speaker.How can hearing aids help?Hearing aids are primarily useful in improving the hearingand speech comprehension of people who have hearingloss that results from damage to the small sensory cellsin the inner ear, called hair cells. This type of hearingloss is called sensorineural hearing loss. The damage canoccur as a result of disease, aging, or injury from noise orcertain medicines.A hearing aid magnifies sound vibrations entering the ear.Surviving hair cells detect the larger vibrations and convertthem into neural signals that are passed along to thebrain. The greater the damage to a person’s hair cells, themore severe the hearing loss, and the greater the hearingaid amplification needed to make up the difference.However, there are practical limits to the amount ofamplification a hearing aid can provide. In addition, if theinner ear is too damaged, even large vibrations will not beconverted into neural signals. In this situation, a hearingaid would be ineffective.How can I find out if I need ahearing aid?If you think you might have hearing loss and could benefitfrom a hearing aid, visit your physician, who may refer youto an otolaryngologist or audiologist. An otolaryngologist isa physician who specializes in ear, nose, and throat disordersand will investigate the cause of the hearing loss. Anaudiologist is a hearing health professional who identifiesand measures hearing loss and will perform a hearing testto assess the type and degree of loss.Are there different styles ofhearing aids?There are three basic styles of hearing aids. The styles differby size, their placement on or inside the ear, and the degreeto which they amplify sound (see figure on page 2).} Behind-the-ear (BTE) hearing aids consist of a hardplastic case worn behind the ear and connected toa plastic earmold that fits inside the outer ear. Theelectronic parts are held in the case behind the ear.Sound travels from the hearing aid through the earmoldand into the ear. BTE aids are used by people of all agesfor 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 aNIDCD.Improving the lives of people with communication disorders
narrow tube inserted into the ear canal,enabling the canal to remain open. Forthis reason, open-fit hearing aids may bea good choice for people who experiencea buildup of earwax, since this type ofaid is less likely to be damaged by suchsubstances. In addition, some people mayprefer the open-fit hearing aid becausetheir perception of their voice does notsound “plugged up.”} In-the-ear (ITE) hearing aids fit completelyinside the outer ear and are used for mildto severe hearing loss. The case holdingthe electronic components is made ofhard plastic. Some ITE aids may havecertain added features installed, such asa telecoil. A telecoil is a small magneticcoil that allows users to receive soundthrough the circuitry of the hearing aid,rather than through its microphone. Thismakes it easier to hear conversations overthe telephone. A telecoil also helps peoplehear in public facilities that have installedspecial sound systems, called inductionloop systems. Induction loop systemscan be found in many churches, schools,airports, and auditoriums. ITE aids usuallyare not worn by young children becausethe casings need to be replaced often asthe ear grows.} Canal aids fit into the ear canal and areavailable in two styles. The in-the-canal (ITC)hearing aid is made to fit the size and shapeof a person’s ear canal. A completely-in canal (CIC) hearing aid is nearly hidden inthe ear canal. Both types are used for mild tomoderately severe hearing loss.Because they are small, canal aids may bedifficult for a person to adjust and remove. Inaddition, canal aids have less space availablefor batteries and additional devices, such asa telecoil. They usually are not recommendedfor young children or for people with severeto profound hearing loss because theirreduced size limits their power and volume.2Styles of hearing aidsReceiver in ear canalBehind-the-ear (BTE)“Mini” BTEIn-the-ear (ITE)In-the-canal (ITC)Completely-in-canal (CIC)Credit: NIH Medical Arts
Do all hearing aids work the same way?Hearing aids work differently depending on theelectronics used. The two main types of electronics areanalog and digital.} Analog aids convert sound waves into electrical signals,which are amplified. Analog/adjustable hearing aidsare custom built to meet the needs of each user. Theaid is programmed by the manufacturer according tothe specifications recommended by your audiologist.Analog/programmable hearing aids have more than oneprogram or setting. An audiologist can program the aidusing a computer, and you can change the program fordifferent listening environments—from a small, quietroom to a crowded restaurant to large, open areas,such as a theater or stadium. Analog/programmablecircuitry can be used in all types of hearing aids. Analogaids usually are less expensive than digital aids.} Digital aids convert sound waves into numericalcodes, similar to the binary code of a computer, beforeamplifying them. Because the code also includesinformation about a sound’s pitch or loudness, theaid can be specially programmed to amplify somefrequencies more than others. Digital circuitry givesan audiologist more flexibility in adjusting the aid toa user’s needs and to certain listening environments.These aids also can be programmed to focus on soundscoming from a specific direction. Digital circuitry can beused in all types of hearing aids.Which hearing aid will work bestfor me?The hearing aid that will work best for you depends onthe kind and severity of your hearing loss. If you have ahearing loss in both of your ears, two hearing aids aregenerally recommended because two aids provide a morenatural signal to the brain. Hearing in both ears also willhelp you understand speech and locate from where thesound is coming.You and your audiologist should select a hearing aidthat best suits your needs and lifestyle. Price is also a keyconsideration because hearing aids range from hundredsto several thousand dollars. Similar to other equipmentpurchases, style and features affect cost. However, don’tuse price alone to determine the best hearing aid foryou. Just because one hearing aid is more expensive thananother does not necessarily mean that it will better suityour needs.A hearing aid will not restore your normal hearing.With practice, however, a hearing aid will increase yourawareness of sounds and their sources. You will wantto wear your hearing aid regularly, so select one that isconvenient and easy for you to use. Other features toconsider include parts or services covered by the warranty,estimated schedule and costs for maintenance and repair,options and upgrade opportunities, and the hearing aidcompany’s reputation for quality and customer service.What questions should I ask beforebuying a hearing aid?Before you buy a hearing aid, ask your audiologist theseimportant questions:} What features would be most useful to me?} What is the total cost of the hearing aid? Do the benefitsof 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 periodduring which aids can be returned for a refund.) Whatfees are nonrefundable if the aids are returned after thetrial period?} How long is the warranty? Can it be extended? Doesthe warranty cover future maintenance and repairs?} Can the audiologist make adjustments and provideservicing and minor repairs? Will loaner aids beprovided when repairs are needed?} What instruction does the audiologist provide?How can I adjust to my hearing aid?Hearing aids take time and patience to use successfully.Wearing your aids regularly will help you adjust to them.Become familiar with your hearing aid’s features. Withyour audiologist present, practice putting in and takingout the aid, cleaning it, identifying right and left aids,and replacing the batteries. Ask how to test it in listeningenvironments where you have problems with hearing.
Learn to adjust the aid’s volumeand to program it for soundsthat are too loud or too soft.Work with your audiologistuntil you are comfortable andsatisfied.You may experience some ofthe following problems as youadjust to wearing your new aid.} My hearing aid feelsuncomfortable. Someindividuals may find ahearing aid to be slightlyuncomfortable at first. Askyour audiologist how longyou should wear your hearingaid while you are adjustingto it.} My voice sounds too loud.The “plugged-up” sensationthat causes a hearing aiduser’s voice to sound louderinside the head is called theocclusion effect, and it isvery common for new hearing aid users. Check withyour audiologist to see if a correction is possible. Mostindividuals get used to this effect over time.} I get feedback from my hearing aid. A whistlingsound can be caused by a hearing aid that does not fitor work well or is clogged by earwax or fluid. See youraudiologist for adjustments.} I hear background noise. A hearing aid does notcompletely separate the sounds you want to hearfrom the ones you do not want to hear. Sometimes,however, the hearing aid may need to be adjusted. Talkwith your audiologist.} I hear a buzzing sound when I use my cell phone.Some people who wear hearing aids or have implantedhearing devices experience problems with the radiofrequency interference caused by digital cell phones. Bothhearing aids and cell phones are improving, however, sothese problems are occurring less often. When you arebeing fitted for a new hearing aid, take your cell phonewith you to see if it will work well with the aid.How can I care for my hearing aid?Proper maintenance and care will extend the life of yourhearing aid. Make it a habit to:} Keep hearing aids away from heat and moisture.} Clean hearing aids as instructed. Earwax and eardrainage can damage a hearing aid.} Avoid using hairspray or other hair care products whilewearing hearing aids.} Turn off hearing aids when they are not in use.} Replace dead batteries immediately.} Keep replacement batteries and small aids away fromchildren and pets.4
Are new types of aids available?Although they work differently than the hearing aidsdescribed above, implantable hearing aids are designedto help increase the transmission of sound vibrationsentering the inner ear. A middle ear implant (MEI) is asmall device attached to one of the bones of the middleear. Rather than amplifying the sound traveling to theeardrum, an MEI moves these bones directly. Bothtechniques have the net result of strengthening soundvibrations entering the inner ear so that they can bedetected by individuals with sensorineural hearing loss.A bone-anchored hearing aid (BAHA) is a small devicethat attaches to the bone behind the ear. The devicetransmits sound vibrations directly to the inner ear throughthe skull, bypassing the middle ear. BAHAs are generallyused by individuals with middle ear problems or deafnessin one ear. Because surgery is required to implant either ofthese devices, many hearing specialists feel that the benefitsmay not outweigh the risks.Can I obtain financial assistance for ahearing aid?Hearing aids are generally not covered by health insurancecompanies, although some do. For eligible children andyoung adults ages 21 and under, Medicaid will pay for thediagnosis and treatment of hearing loss, including hearingaids, under the Early and Periodic Screening, Diagnostic,and Treatment service. Also, children may be covered bytheir state’s early intervention program or State Children’sHealth Insurance Program.Medicare does not cover hearing aids for adults; however,diagnostic evaluations are covered if they are ordered bya physician for the purpose of assisting the physician indeveloping a treatment plan. Since Medicare has declared theBAHA a prosthetic device and not a hearing aid, Medicarewill cover the BAHA if other coverage policies are met.Some nonprofit organizations provide financial assistancefor hearing aids, while others may help provide used orrefurbished aids. Contact the National Institute on Deafnessand Other Communication Disorders (NIDCD) InformationClearinghouse with questions about organizations thatoffer financial assistance for hearing aids.5What research is being done onhearing aids?Researchers are looking at ways to apply new signalprocessing strategies to the design of hearing aids. Signalprocessing is the method used to modify normal soundwaves into amplified sound that is the best possible matchto the remaining hearing for a hearing aid user. NIDCDfunded researchers also are studying how hearing aids canenhance speech signals to improve understanding.In addition, researchers are investigating the use ofcomputer-aided technology to design and manufacturebetter hearing aids. Researchers also are seeking waysto improve sound transmission and to reduce noiseinterference, feedback, and the occlusion effect.Additional studies focus on the best ways to select and fithearing aids in children and other groups whose hearingability is hard to test.Another promising research focus is to use lessons learnedfrom animal models to design better microphones forhearing aids. NIDCD-supported scientists are studying thetiny fly Ormia ochracea because its ear structure allowsthe fly to determine the source of a sound easily. Scientistsare using the fly’s ear structure as a model for designingminiature directional microphones for hearing aids. Thesemicrophones amplify the sound coming from a particulardirection (usually the direction a person is facing), but notthe sounds that arrive from other directions. Directionalmicrophones hold great promise for making it easierfor people to hear a single conversation, even whensurrounded by other noises and voices.
Where can I find additionalinformation about hearing aids?For more information, additional addresses and phonenumbers, or a printed list of organizations, contact us at:The NIDCD maintains a directory of organizations thatprovide information on the normal and disorderedprocesses of hearing, balance, taste, smell, voice,speech, and language. Visit the NIDCD website athttp://www.nidcd.nih.gov to search the directory.NIDCD Information Clearinghouse1 Communication AvenueBethesda, MD 20892-3456Toll-free Voice: (800) 241-1044Toll-free TTY: (800) 241-1055Fax: (301) 770-8977Email: nidcdinfo@nidcd.nih.govUse the following keywords to help you findorganizations that can answer questions and provideprinted or electronic information on hearing aids:} Hearing aidshttp://www.nidcd.nih.govFollow the NIDCD on Twitter at @NIDCD} Assistive listening device} Assistive technologyMore NIDCD fact sheets on Hearing and Balance:} Age-Related Hearing Loss} Hearing Loss and Older Adults} Noise-Induced Hearing LossThe NIDCD supports and conducts research andresearch training on the normal and disorderedprocesses of hearing, balance, taste, smell, voice,speech, and language and provides health information,based upon scientific discovery, to the public.} Otosclerosis} TinnitusVisit the NIDCD website at http://www.nidcd.nih.govto read, print, or download fact sheets.Hearing AidsNIH Pub. No. 99-4340September 2013Reprinted July 2015NIH.Turning Discovery Into Health
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 .
hearing aids that fit well and that are good for your type of hearing loss. If you buy your hearing aids privately, you'll be able to choose your hearing aids and spend as much as you want to on them. Private hearing aids costs Private hearing aids usually cost between 500 and 3,500, but sometimes they cost more. You'll have to pay again
Do not drop your hearing aids. Dropping onto a hard surface can damage your hearing aids. Store your hearing aids in the charger if you are not using them for a long period of time. The hearing aids have to be dry before charging. Otherwise the charging reliability cannot be guaranteed. The use of hearing aids is only part of
TABLE OF CONTENTS PART 1 Hearing & Hearing Loss 1.1 Introduction 04 1.2 How We Hear 07 1.3 Types of Hearing Loss 09 1.4 Degree of Hearing Loss 11 1.5 Signs of Hearing Loss 13 1.6 What Should You Do? 14 PART 2 Hearing Aids 2.1 Introduction 15 2.2 Types of Hearing Aids 17 2.3 In-the-Ear Styles 19 2.4 Behind-the-Ear Styles 20 2.5 Choosing a Hearing Aid 22
Set up the hearing aids 18 2 Connect your phone To control the hearing aids using the Bose Hear app, you must connect your phone with the hearing aids. To connect your phone, follow the steps below. Step 1: Download the Bose Hear app (see page 19). Step 2: Insert the batteries and fully close the battery doors to power on the hearing aids (see .
OPEN ACCESS GUIDE TO AUDIOLOGY AND HEARING AIDS FOR OTOLARYNGOLOGISTS FITTING HEARING AIDS: CLINICAL & PRACTICAL ASPECTS Faheema Mahomed-Asmail, Anel Le Roux, Claude Laurent This is the 2nd of two chapters on fitting hearing aids. The 1st chapter deals with the technical aspects of hearing aids, whereas this chapter deals with how best to accom-
Your hearing aids and its batteries need to rest when you do. You must always take your hearing aids off at night when you go to sleep. To make sure that the hearing aids and batteries are ready for the next day open the battery compartment completely over night; you don‛t need to remove the batteries. If the hearing aids have been
Ordering and Fitting Hearing Aids Authorization for Hearing Aids Before ordering a hearing aid you must determine if the worker is eligible for a hearing aid device. Use the information below to help determine eligibility: First time hearing aids The worker should present their decision letter stating that their claim is approved and hearing .
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