Hearing From Sound to Signal: How Hearing Works

Hearing is a complex sense that involves converting sound vibrations into electrical signals. Hearing loss can happen at multiple points along that journey. Hearing aids can sometimes help.

Sounds are pressure waves that send air (or other materials) molecules into vibration. These vibrations interact with human ears and are converted into electrical messages that are delivered to the brain through nerves.

The ear itself consists of the outer ear, the middle ear, and the inner ear. The outer ear includes the ear canal, which conducts the sound, and the ear drum, which receives the sound.

The middle ear consists of three tiny bones called ossicles which pick up the vibrations of the ear drum and transmit them into the fluid-filled inner ear through a membrane known as the oval window.

The inner ear is a snail-shaped organ containing fluid and specialized cells called hair cells. These cells pick up the vibrations that were passed into the inner ear by the ossicles and convert them into electrical signals that then go to the brain via nerves.

Conductive hearing loss results from a problem with the outer or middle ear.  Hearing aids help people with conductive hearing loss.   Hearing aids work like a microphone and speaker system to pick up sound and increase the volume of the sound making its way down the ear canal.

Other types of hearing loss are known as sensorineural, central, or mixed hearing loss. Sensorineural hearing loss, which involves a problem with the inner ear or the nerves that carry the signals to the brain. Central hearing loss occurs when the part of the brain that handles hearing is damaged. Mixed hearing loss is a mixture of these problems.

While not all people with hearing loss can benefit from hearing aids, they can be beneficial to many.