How Hearing Aids Work

Many people with hearing loss, whether mild or severe, use a device to assist with hearing and speech. These devices are commonly called “hearing aids.” But how do hearing aids work?

A hearing aid is a small, battery-powered device that fits onto and/or into the ear to provide the user with enhanced sound reception and comprehension. Essentially, the hearing aid is both a microphone and a speaker. The microphone receives sound from the user’s surrounding environment, and the device amplifies the sound signal and projects it via the small speaker directly into the user’s ear canal.

Hearing aids are generally used by people who have experienced hearing loss caused by damage to “hair cells” in the ear. These cells are sensitive, reacting to the vibrations created by sounds in the environment and eventually translating the sound as a signal to the brain. Many people suffer damage to these hair cells caused by exposure to excessively loud noise or from disease. Others simply lose hearing as they age.

The severity of hearing loss depends on how many hair cells have been damaged. A hearing aid can assist those with significant hearing loss by amplifying sound and directing it into the ear. When a hearing aid is in place, the surviving hair cells remaining in the ear react to the louder sound projected from the device’s speaker and send a natural signal to the brain. A patient who has more extensive hair cell damage will require a device with more powerful sound amplification. If the inner ear is severely damaged, a hearing aid may not be effective because few or no hair cells remain to receive the amplified sound.

There are both analog and digital hearing aids. Analog devices are less expensive yet still provide hearing options for the user. Circuitry in an analog hearing aid converts sound waves into electrical signals and amplifies them. With most models, the user is able to adjust the volume of the speaker manually for different listening environments. Digital aids, on the other hand, actually have processing chips that convert sound waves into numerical code. This technology allows for the sound signal to be manipulated by the device before it is amplified and sent through the speaker, giving doctors the ability to program the device to receive or block certain frequencies. Digital hearing aids allow specialists to more closely tailor the performance of the device to their patient’s hearing needs.

There are many different types and qualities of analog and digital hearing aids. If you think you may need a hearing aid, schedule an appointment with an audiologist at Arkansas Otolaryngology Center to discuss options that suit your needs.