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hearing aid |
Also found in: Medical, Wikipedia, Hutchinson | 0.01 sec. |
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hearing aid, device used in some forms of deafness to amplify sound before it reaches the auditory organs. Modern hearing aids are electronic. They contain a tiny receiver and a transistor amplifier, and are usually battery powered. Some are small enough to fit into an arm of a pair of eyeglasses, or into the outer ear. The bone-conduction hearing aid, placed behind the ear, channels sound waves to the adjacent bony part of the skull, which then transmits the vibrations to the auditory nerve of the cochlea. The air-conduction hearing aid amplifies sounds and directs them into the ear toward the tympanic membrane. In recent years, a number of advancements have been made to hearing aids, improving the comfort, sensitivity, and aesthetic quality of the devices. Today, many hearing aids are customized to amplify only those noises (e.g., high frequency) that the user has difficulty hearing. Cochlear implants have been developed for use by certain totally deaf people. They consist of mechanical replacements for ineffective hair cells in the inner ear, which transform sound vibrations into electronic impulses that stimulate the auditory nerve. hearing aidDevice that increases the loudness of sounds in the user's ear. Its principal components are a microphone, an amplifier, and an earphone. Hearing aids are increasingly smaller and less conspicuous, fitting behind the earlobe or within the ear canal. They have widely differing characteristics, amplifying different components of speech sounds for maximum comprehension by each wearer. Hearing aids with automatic volume control vary the amplification automatically with the input. hearing aid a device for assisting the hearing of partially deaf people, typically consisting of a small battery-powered electronic amplifier with microphone and earphone, worn by a deaf person in or behind the ear hearing aid [′hir·iŋ ‚ād] (engineering acoustics) A miniature, portable sound amplifier for persons with impaired hearing, consisting of a microphone, audio amplifier, earphone, and battery. How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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