What is the inner ear?

The inner ear is invisible from outside your body, but its role in hearing is critical.  This is where cells and nerves process sound and send it to the brain. A lot of age-related hearing loss takes place in the inner ear, because these important cells and nerves deteriorate with age. The inner ear also helps us keep our balance. 

The cochlea

The cochlea is a hollow, spiral-shaped cavity deep inside your ear. It looks a bit like a snail shell - in fact, the name cochlea is derived from the Greek word for “snail.” Sound is transformed in the cochlea by 15,000 tiny hair cells. When these hair cells deteriorate, you may have trouble hearing. 

The auditory nerve

The other important part of your inner ear anatomy is the auditory nerve. It carries sound from the cochlea to your brain. 

What happens in the inner ear?

The cochlea’s hair cells convert sound into electrical signals. Those electrical signals are transmitted via neurotransmitters along the auditory nerve to the brain, which can then analyze what you are hearing.

The inner ear
and hearing loss

When you have hearing loss based in your inner ear, it is usually called sensorineural hearing loss. This can usually be treated with amplification from good hearing aids. In some cases, a “cochlear implant” may be considered to improve the function of the inner ear anatomy. 
Sensorineural hearing loss
Hearing care professional testing a patient's hearing.