Hearing and Balance Anatomy

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The anatomy of the ear can be a little confusing, especially since the ear is responsible not only for hearing, but also for balance.

There are three components to the ear: the outer ear, the middle ear and the inner ear. All three are involved in hearing but only the inner ear is responsible for balance.

The outer ear is composed of the pinna, or ear lobe, and the external auditory canal. Both structures funnel sound waves towards the ear drum or tympanic membrane allowing it to vibrate. The pinna is also responsible for protecting the ear drum from damage. Modified sweat glands in the ear canal form ear wax.

The middle ear is an air filled space located in the temporal bone of the skull. Air pressure is equalized in this space via the Eustachian tube which drains into the nasopharynx or the back of the throat and nose. There are three small bones, or ossicles, that are located adjacent to the tympanic membrane. The malleus, incus, and stapes are attached like a chain to the tympanic membrane and convert sound waves that vibrate the membrane into mechanical vibrations of the three bones. The stapes fills the oval window which is the connection to the inner ear.

Medically Reviewed by a Doctor on 12/1/2014