The ear is a clever and complex organ that allows us to hear and helps us keep our balance. It has three main parts: the outer ear, middle ear, and inner ear.

Outer Ear

The outer ear includes the pinna (the part you can see) and the ear canal.

The pinna works like a funnel, collecting sound from the environment and directing it into the ear canal. It also helps your brain work out where sounds are coming from by subtly changing how sound enters the ear.

The ear canal carries sound down toward the eardrum. It is slightly curved and has tiny hairs and ear wax (cerumen), which help protect the ear by trapping dust, dirt, and foreign objects.

Middle Ear

The middle ear sits just behind the eardrum and contains the eardrum and three small bones called the ossicles:

• Malleus (hammer)
• Incus (anvil)
• Stapes (stirrup)

When sound reaches the eardrum, it causes it to vibrate. These vibrations are passed along the ossicles, which amplify the sound and send it into the inner ear.

Inner Ear

The inner ear contains the cochlea (for hearing) and the balance system (vestibular system).

The cochlea is a small, snail-shaped, fluid-filled structure. When sound vibrations enter it, they move through the fluid and stimulate tiny sensory cells called hair cells.

Different hair cells respond to different pitches:

• High-pitched sounds are detected at the base of the cochlea
• Low-pitched sounds are detected toward the top

How We Hear

When hair cells are stimulated, they turn sound vibrations into electrical signals. These signals travel along the hearing nerve (auditory nerve) to the brain, where they are interpreted as sound.

Hearing loss is a very common condition, affecting around 1 in 6 Australians. With increasing exposure to loud noise (such as headphones and concerts) and an ageing population, this is expected to rise to 1 in 4 people by 2050.

Hearing loss can affect people in different ways depending on where the problem occurs in the hearing system.