How Hearing Aids Work

The Parts of Hearing Aids

1. Microphone- Located on the outside of the hearing aid. It picks up the sound from the air as it enters the ear and converts sound waves into digital sound.
2. Microchip- A miniature computer enabling specialists to customize your hearing aid to your specific hearing loss.
3. Amplifier- The amplifier strengthens the digital sound.
4. Battery- The batteries power the hearing aid. 
5. Receiver- Converts the digital sound into vibrations that travel to your inner ear. 

Hearing aids have a microphone, amplifier and speaker. Sound is received by the microphone, which converts the sound waves to electrical signals and sends them to an amplifier. The amplifier boosts the signals and then sends them to the ear through a speaker.

Hearing aids are primarily useful to people who have suffered sensorineural hearing loss from damage to the small sensory cells in the inner ear known as hair cells. The damage can be caused by disease, aging or injury from noise or drugs.

A hearing aid magnifies sound vibrations. Surviving hair cells detect the larger vibrations and convert them into signals that are sent to the brain.

There are limits to the amplification a hearing aid can provide. In addition, if the inner ear is too damaged, even large vibrations will not be converted into signals to the brain.