How the ear works

Sounds reach our ears as sound waves. These move through the ear canal to the eardrum which vibrates.

ear diagram

Outer ear

This is the part of the ear that your doctor or audiologist can see and examine.

The pinna acts like a satellite dish, gathering sound which then travels through the ear canal to reach the eardrum, making it vibrate. 


Middle ear

The middle ear includes the Eustachian tube and three tiny bones (ossicles) called the malleus, incus and stapes (or hammer, anvil and stirrup).

When the eardrum vibrates, the ossicles move. The smallest bone, the stapes, is connected to the oval window which lies between the middle ear and inner ear.

The middle ear focuses and amplifies the sound and sends it on to the inner ear via the oval window. 


Inner ear

The inner ear is made up of two parts - the hearing organ (cochlea) and the balance organ (semi-circular canals).

The cochlea is a coiled hollow tube, filled with fluid and lined with thousands of sensory cells known as ‘hair cells’. The vibrations of the oval window cause waves in the fluid and the cells convert these waves into electrical signals.

The auditory nerve passes the signals to the brain which recognizes them as different sounds.

 

Date of review – January 2013

Date for next review – January 2015

Last updated on 15th January 2013

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