What cranial nerve is number 8?
vestibulocochlear nerve
The vestibulocochlear nerve, also known as cranial nerve eight (CN VIII), consists of the vestibular and cochlear nerves.
What does the 8th cranial nerve innervate?
The vestibulocochlear nerve has two components within a single trunk: the vestibular nerve, which innervates the semicircular canals of the inner ear and is involved with equilibrium, coordination, and orientation in space, and the cochlear nerve, which innervates the cochlea and subserves hearing.
What happens if cranial nerve 8 is damaged?
CN VIII pathology can result from direct trauma, congenital malformations, tumor formation, infection, and vascular injury. Presenting symptoms include vertigo, nystagmus, tinnitus, and sensorineural hearing loss.
What function does CN VIII vestibulocochlear have?
The vestibulocochlear nerve or auditory vestibular nerve, also known as the eighth cranial nerve, cranial nerve VIII, or simply CN VIII, is a cranial nerve that transmits sound and equilibrium (balance) information from the inner ear to the brain.
How do you test cranial nerve 8?
The cochlear division of CN 8 is tested by screening for auditory acuity. This can be done by the examiner lightly rubbing their fingers by each ear or by using a ticking watch.
Is cranial nerve 8 sensory or motor?
Sensory
Table of cranial nerves
| No. | Name | Sensory, motor, or both |
|---|---|---|
| VIII | Vestibulocochlear In older texts: auditory, acoustic. | Mostly sensory |
| IX | Glossopharyngeal | Both sensory and motor |
| X | Vagus | Both sensory and motor |
| XI | Accessory Sometimes: cranial accessory, spinal accessory. | Mainly motor |
What happens when the vestibulocochlear nerve is damaged?
The vestibular nerve communicates messages about head position and motion from your inner ear to your brain. When this nerve is damaged, these messages become jumbled and inaccurate, confusing your brain and producing the dizziness, nausea and movement issues.
Can the 8th cranial nerve be repaired?
Treatment. If a cranial nerve is completely cut in two, it cannot be repaired. However, if it is stretched or bruised but the nerve remains intact, it can recover. This takes time and can cause a variety of unpleasant symptoms including tingling and pain.
Which part of CN VIII is involved in hearing and which part is involved in balance?
The vestibulocochlear nerve (also known as the auditory vestibular nerve and cranial nerve VIII) has axons that carry the modalities of hearing and equilibrium. It consists of the cochlear nerve that carries information about hearing, and the vestibular nerve that carries information about balance.
Where is CN VIII from?
The roots arise from the vestibular and cochlear nuclei located in the brainstem. The fibers from both roots merge to form the vestibulocochlear trunk of the nerve that is found in the posterior cranial fossa in the petrous part of the temporal bone.
What would happen if the vestibulocochlear nerve was damaged?
What is special about the vagus nerve?
The vagus nerve is the longest cranial nerve. It contains motor and sensory fibers and, because it passes through the neck and thorax to the abdomen, has the widest distribution in the body. It contains somatic and visceral afferent fibers, as well as general and special visceral efferent fibers.