Labyrinthitis
A prominent and debilitating symptom of labyrinthitis is acute vertigo
The vestibular system is a set of sensory inputs consisting of three semicircular canals, sensing changes in rotational motion, and the otoliths, sensing changes in linear motion. The brain combines visual cues with sensory input from the vestibular system to determine adjustments required to retain balance. When working properly, the vestibular system also relays information on head movement to the eye muscle, forming the vestibulo-ocular reflex, in order to retain continuous visual focus during motion. When the vestibular system is affected by labyrinthitis, rapid, undesired eye motion (nystagmus), often results from the improper indication of rotational motion. Nausea, anxiety, and a general ill feeling are common due to the distorted balance signals that the brain receives from the inner ear.
http://www.emedicinehealth.com/labyrinthitis/article_em.htm
This can also be brought on by pressure changes such as those experienced while flying or scuba diving