Definition
noun
A short, narrow passageway through the temporal bone of the skull where the vestibular nerve and cochlear nerve pass through to reach the brainstem from the inner ear.
Supplement
In humans, the internal auditory canal is about 1-2 cm in length. Aside from the vestibular nerve (responsible for balance) and cochlear nerve (responsible for hearing), the facial nerve also runs through this tube.
The IAC opens to the inside of the cranial cavity, near the center of the posterior surface of the temporal bone, and the opening is called ”internal acoustic opening”. At the other end of IAC are the openings for the vestibulocochlear and facial nerves.
Unlike the external auditory canal that transmits sound waves, the internal auditory canal carries the the facial and vestibulocochlear nerves that transmit information to the brain.
Abbreviation: IAC
Synonyms:
- meatus acusticus internus
- internal acoustic meatus
- internal auditory meatus
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