Hearing Loss Basics: How We Hear

Before you try to understand the reasons for your hearing loss, it is important to understne the basics of how we hear.

The ear is divided into three parts leading up to the brain – the outer ear, middle ear and the inner ear-- and hearing loss can occur when any of these pieces is damaged or altered in any way.

The outer ear consists of the ear canal and eardrum. Sound travels down the ear canal, striking the eardrum and causing it to move or vibrate.

The middle ear is a space behind the eardrum that contains three small bones called ossicles. This chain of tiny bones is connected to the eardrum at one end and to an opening to the inner ear at the other end. Vibrations from the eardrum cause the ossicles to vibrate which, in turn, creates movement of the fluid in the inner ear.

Movement of the fluid in the inner ear, or cochlea, causes changes in tiny structures called hair cells. This movement of the hair cells sends electric signals from the inner ear up the auditory nerve (also known as the hearing nerve) to the brain. Any damage to these hair cells can lead to hearing loss.

The brain then interprets these electrical signals as sound.

To see it in action, check out this video on the basics of how we hear.