Outer ear

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Outer ear
External and middle ear, opened from the front. Right side.
The auricula. Lateral surface.
Gray's	subject #229 1033
MeSH	External+Ear

The outer ear is the external portion of the ear.

[edit] Pinna, or auricle

The visible part is called the pinna and functions to collect and focus sound waves. Many mammals can move the pinna (with the auriculares muscles) in order to focus their hearing in a certain direction in much the same way that they can turn their eyes. Humans, unlike most other mammals, do not have this ability....

[edit] Ear canal, or external auditory meatus

From the pinna the sound pressure waves move into the ear canal, a simple tube running to the middle ear. This tube amplifies frequencies in the range 3 kHz to 12 kHz.

Sensory system - Auditory system - edit

Outer ear: Pinna | Ear canal  Middle ear: Eardrum | Ossicles (Malleus, Incus & Stapes) | Stapedius | Tensor tympani | Eustachian tube Inner ear: Cochlea (Scala vestibuli, Scala media & Scala tympani) | Oval window | Helicotrema | Round window | Basilar membrane | Reissner's membrane | Organ of Corti | Hair cells | Stereocilia Brain: Cochlear nerve VIII → Cochlear nuclei → Superior olivary nuclei → Lateral  lemniscus  → Inferior colliculi → Medial geniculate nuclei → Primary auditory cortex