Description and Physiology
The eighth cranial nerve is the vestibulocochlear nerve. This nerve has several other names such as the auditory nerve, acoustic nerve, or the auditory-vestibular nerve. The vestibulocochlear nerves runs laterally on both sides of the facial nerves. The vestibulocochlear nerve is primarily a sensory nerve responsible for the sense of hearing and the sensation of equilibrium. This nerve innervates the cochlea of the ear for hearing through the cochlear branch. The vestibulcochlear nerve also innervates the vestibular branch found in the inner ear, which is responsible for balance. Through our vestibulcochlear nerves we are able to sense sounds, gravity, and body rotation. When this nerve has been damaged a person may experience a false sense of movement, vertigo, or even hearing loss.
Vestibular neuritis often occurs due to an inflammation of the vestibulocochlear nerve in the inner ear. The chief symptom of vestibular neuritis is sudden vertigo, which may feel like the room is spinning or balance has been lost. The vertigo may last several days or a few weeks. Other symptoms associated with vestibular neuritis include vomiting and nausea. The neuritis often comes after a viral infection and so researchers believe the neuritis may be cause by a virus. Incorrect body movement signals are sent to the brain by the inflamed nerve and since those sensory signals do not match signals from other senses like the eyes it creates a feeling of vertigo. Antibiotics do not treat the condition, but vestibular neuritis generally resolves itself with time.
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