Outer ear

As its name indicates the outer ear is the outermost part of the auditory system.

Structure of the outer ear

The outer ear is both a protective and resonance structure and is made up of the pinna (or auricular shell) and the auditory canal which leads to the tympanic membrane.

Role of the outer ear

The pinna captures and concentrates sound waves while buffering sudden transfer of open air into the enclosed air in the auditory canal. These acoustic waves then pass along the auditory canal behaving as rectilinear waves over approximately 2 to 3 centimetres before encountering the tympanic membrane. This then oscillates in response to fluctuations in the acoustic wave in the canal.

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