Outer ear

Outer ear refers to the external part of the ear, which includes the pinna, the ear canal, and the eardrum. It plays a crucial role in the process of hearing by collecting sound energy and directing it to the middle and inner ear.

Anatomy

The outer ear consists of two main parts: the pinna (or auricle) and the external auditory canal.

Pinna

The pinna is the visible part of the ear that resides outside of the head. Its primary function is to collect sound, and includes the following parts: the helix, antihelix, concha, tragus, and lobule.

External Auditory Canal

The external auditory canal is a tube running from the outer ear to the middle ear. The adult human ear canal extends from the pinna to the eardrum and is about 2.5 cm in length and 0.7 cm in diameter.

Function

The outer ear serves several key functions in the hearing process. It helps in localizing sound sources, and it amplifies sound, particularly those frequencies associated with human speech.

Clinical significance

Conditions that can affect the outer ear include otitis externa, cellulitis, and earwax blockage. These conditions can lead to symptoms such as ear pain, hearing loss, and tinnitus.

See also

• Middle ear
• Inner ear
• Hearing

References

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  Anatomy of the Human Ear
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  Outer ear
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  Outer ear
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  Outer ear
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  Outer ear