Human uses 3 main systems to stay in balance in space. First one is the vestibuler system located in the inner ear, the second is vision and the third is proprioception. The vestibular system is located behind the hearing part in the inner ear and, unlike the other systems, its only function is the sense of balance.
Describing purposes, imagine a hose full of water. When we move the hose in one direction, the water in it can not be adapted to that action and moves in the opposite direction. The parts of the vestibular system are the same rationale ruled by the nerves that perceive this reverse rubbing. Semicircular canals settled in three directions are a system of perception carried to the brain. Utriculus and sacculus are the detectors of the vertical motion similarly.
Positional vertigo is the most common type of equilibrium disorder among people. Here a displacing otolite particle irritates the vestibuler system causing a false motion effect. This cause patient to move opposite side as a deffence. This phenomenon more frequently occure in the horizontal semicircular channel. In treatment the displaced particle must be repositionedby using a method called Epley maneuver. If treated properly, using this maneuver, an immediate improvement is seen.
Another common cause of vertigo is Meniere's disease. The reason of the symptoms arouse because of the overpressure in the inner ear fluid system. Meniere disease, differently, hearing symptoms like hearing loss and tinnitus accompany the picture.