How we hear

Outer ear - The outer ear consists of what we see on the sides of our head, and the ear canal. The purpose of the outer ear is to collect sound and transfer it down the ear canal to the eardrum.

Middle ear - The middle ear is made up of the eardrum, and a cavity which contains the three smallest bones in our body (malleus, incus, and stapes). The eardrum vibrates when sound reaches it, and those vibrations are carried along the three tiny bones to the inner ear.

Inner ear - The inner ear is simply a snail shaped cavity inside our skull. Inside the cavity are small fluid filled chambers and thousands of tiny hair cells. The hair cells are connected to nerves that carry signals to the brain. When vibrations reach the inner ear, they create waves which stimulate the tiny hair cells. When the hair cells are stimulated signals are sent to the brain and processed as sound.

This is a highly simplified explanation of our hearing. For a more detailed explanation of the anatomy and physiology of hearing, visit your local library and search under the subject "audiology". Also see our links page.