What is the eighth cranial nerve?
nerves in the brain are called cranial nerves. There are 12 pairs of which each has specific sensory or motor functions. One of these nerves is the vestivuloclear nerve, also known as the eighth cranial nerve. The eighth cranial nerve consists of two sensory branches, vestibular nerve and cochlear or auditory nerve. Hearing is a function of a cochlear nerve, while the sense of position of the body comes from a vestibular nerve.
The eighth skull nerve is formed from the brain stem, which is connected to the spinal cord and is located on the skull base. It travels from the inner part of the ear towards the brain. In the inner ear are receptor cells that receive sound vibrations and noise from the outside, which then stimulates the cochlear nerve to send these sounds to the brain for interpretation. Head movements also affect the fluid inside the ear and stimulate the vestibular nerve to send information to the brain about the feeling of balance or position.
injury or afterThe damage of one branch of the eighth skull nerve often leads to several symptoms. When the cochlear nerve is affected, they include manifestations of tinnitus or the ringing of the ear, poor auditory skills and deafness. Hearing loss is usually caused by noise exposure, otitis media or inflammation of the middle part of the ear, the idea of ear wax or blocking and presbycusis. Presbycusis is a term referring to hearing loss bringing old age. Some infants can also be born with defects in the cochlear nerve and the deaf throughout their lives.
When a vestibular branch of the eighth skull nerve is affected by injury or disease, symptoms usually include dizziness, nausea, ataxia, vomiting and nystagmus. Ataxia means instability or instability in voluntary movement. Nystagmus refers to unusual and involuntary fast eye movements. Disabled patients also show vertigo or false feeling that the environment is spinning. Causes often include tumors, degenerative diseases, vestibular neuritis and intoxication from drugs oralcohol.
The diagnosis of the eighth cranial nerve injury is often made by a neurologist, a doctor who treats the nervous system diseases. He usually takes the patient's medical and family history and then performs special tests to evaluate the function of the eighth skull nerve. Other diagnostic tools, which can also be useful, include magnetic resonance scanning (MRI) and computer tomography (CT). Treatment often depends on the cause of the patient's symptoms.