How Hearing Aids Work

By Author: Kamal Elliot
Total Articles: 2
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Hearing aids are basically very small amplifiers. However, with modern digital technology, digital hearing instruments can be very precisely manipulated to customize a specific patient’s hearing loss and hearing lifestyle. Every analog and digital aid has a microphone, a small loudspeaker (receiver), and a battery.

All hearing instruments are powered by a zinc-air battery. Zinc-air batteries are small, button-like batteries with a beveled edge on one side and a flat side. The flat side has a small color coded sticker tab that indicates what size battery it is. Zinc-air batteries are activated by exposure to air. Once the colored sticker tab is removed, the battery immediately begins to drain. Placing the tab back on the flat side will not prevent the battery from continuing to drain. This power allows the other parts (e.g., microphone, receiver, etc.) to work.

Sound enters the hearing instrument through the microphone port(s) on the outer case of the aid. On in-the-ear styles, microphones are usually located around the battery door. On behind-the-ear styles, the microphone port(s) are typically located near the ...
... top of the aid where the instrument sits over the ear. Incoming sound waves are converted to an electric signal, amplified, and converted back into an audible sound. The receiver, sitting in the outer ear canal, plays the amplified sound to your ear. If the hearing instrument is digital, a computer chip is also a main component. This computer chip converts incoming sound into digital codes (i.e., strings of numbers). This sampling and coding allows for the sound to be easily modified to suit the individuals hearing impairment.

While modern digital aids are very sophisticated pieces of technology with noise reduction algorithms, feedback (whistling) cancellers, and the like, they are still an amplifier at their core and cannot restore hearing to normal. Sound must still pass through a damaged system, and the brain will need time to adjust to its newfound sounds. Your hearing decreases may have been so gradual that you may not realize all the sounds you have lost. Small, insignificant sounds like the hum of your air conditioner, the noise of the road, the birds chirping early in the morning – your brain will have to re-learn all of these now “new” sounds. Initially, these sounds may seem particularly bothersome, but with consistent wear, acclimation and benefit should increase. Most people will notice an almost instantaneous benefit during one-on-one conversations, in quiet and overall greater ease when listening with their hearing aids.

Kamal Elliot, Au.D. Doctor of Audiology Dr. Elliot is a licensed Audiologist who earned her Doctor of Audiology degree from the University of Florida and has been practicing since 1994. Dr. Elliot has over 17 years of experience and she brings a wealth of knowledge in audiology and hearing aid services. She is dedicated and committed to continuing to provide quality hearing care to you and the entire Sun City Center, Florida and Hillsborough County community.