What is the Use of External Ears?

The external ears, also known as the auricle or pinna, are the visible part of the ear that protrude from the side of the head. While the external ears are often considered a cosmetic feature, they serve several important functions related to hearing and balance. In this article, we will explore the anatomy and function of the external ears.

Anatomy of the External Ears

The external ears consist of several parts, including the helix, antihelix, tragus, antitragus, lobule, and concha. The helix is the outer rim of the ear, while the antihelix is the curved ridge of cartilage just inside the helix. The tragus is the small, triangular projection that extends over the ear canal, while the antitragus is the smaller projection opposite the tragus. The lobule is the soft, fleshy lower part of the ear, while the concha is the bowl-shaped depression at the center of the ear.

The external ear is covered in skin and is supported by a flexible cartilage framework. The skin of the external ear contains sebaceous and sweat glands, which help to keep the ear clean and moisturized. The external ear canal, which is the passageway from the outer ear to the eardrum, is also part of the external ear.

Function of the External Ears

The external ears serve several functions related to hearing and balance. The most obvious function of the external ears is to collect sound waves and funnel them into the ear canal. The shape of the external ear, particularly the concha and the folds of the helix and antihelix, help to amplify and direct sound waves toward the eardrum.

The external ears also play a role in localization, or the ability to determine the direction from which a sound is coming. This is accomplished through the use of binaural cues, which are differences in the arrival time, intensity, and spectral content of sounds at the two ears. The external ears help to enhance these binaural cues, which are important for spatial hearing.

In addition to hearing, the external ears are also involved in balance. The semicircular canals, which are part of the inner ear, are responsible for detecting changes in head position and movement, which are important for maintaining balance. The external ears, particularly the semicircular canals, play a role in detecting these movements and sending signals to the brain to help maintain balance.

Disorders of the External Ears

Disorders of the external ears can affect hearing and balance. One common disorder of the external ear is otitis externa, which is an infection of the outer ear canal. This condition, also known as swimmer's ear, can cause pain, swelling, and discharge from the ear. It is often treated with topical antibiotics and ear drops.

Another disorder of the external ear is exostosis, which is the abnormal growth of bone in the ear canal. This condition, also known as surfer's ear, can be caused by exposure to cold water and wind. Exostosis can cause hearing loss and can be treated with surgical removal of the bone growth.


The external ears are an important part of the auditory system and play a crucial role in hearing and balance. The unique anatomy of the external ear helps to collect and amplify sound waves and enhance binaural cues for spatial hearing. Disorders of the external ear, such as otitis externa and exostosis, can affect hearing and balance and may require medical treatment.

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