Eighth cranial nerve

Eighth Cranial Nerve

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The eighth cranial nerve, also known as the vestibulocochlear nerve.

The Eighth Cranial Nerve or Vestibulocochlear Nerve is one of the twelve Cranial nerves that originate from the brain. It is responsible for transmitting sound and equilibrium (balance) information from the inner ear to the brain. The nerve is divided into two parts: the cochlear nerve, which carries information about hearing, and the vestibular nerve, which carries information about balance.

Structure

The eighth cranial nerve is composed of two distinct parts: the cochlear nerve and the vestibular nerve. The cochlear nerve originates from the cochlea in the inner ear where it receives sound in the form of vibrations. The vestibular nerve originates from the vestibular system of the inner ear and is involved in the sensation of balance.

Function

The cochlear part of the eighth cranial nerve is involved in the process of hearing. It transmits sound information from the cochlea to the auditory cortex in the brain. The vestibular part of the nerve is responsible for balance. It transmits information from the semicircular canals, which sense rotation of the head, and the otoliths, which sense linear acceleration and the force of gravity.

Clinical significance

Damage to the eighth cranial nerve can cause vestibular disorders, including vertigo, tinnitus, and hearing loss. These conditions can be caused by a variety of factors, including aging, exposure to loud noise, certain medications, and diseases such as Meniere's disease and acoustic neuroma.

See also

• Cranial nerves
• Inner ear
• Vestibular system