The peripheral fibers divide into three branches (some sources list two):[1] The primary role of the vestibular nerve is to transmit information about balance of the head in relation to the body.

As an example, when standing upright and facing forward, if you wished to tilt your head to the right you would need to perform a slight leftward motor movement (shifting more of your weight to your left side) to maintain balance.

[3] The most common causes of damage to the vestibular nerve are exposure to ototoxic antibiotics, Ménière's disease, encephalitis and some rare autoimmune disorders.

[3] Typically, patients with a damaged nerve suffer from acute attacks of vertigo accompanied by nausea/vomiting, inability to maintain posture and horizontal nystagmus.

By administering betahistine to the damaged nerve over a long period of time, the process of vestibular compensation can be accelerated to alleviate symptoms.