Benign positional vertigo (BPV)-or simply vertigo-is a disorder of the inner ear. You feel a sudden sensation of movement or spinning when you move your head or hold it in a certain position. The inner ear is located within your skull and consists of the cochlea, a chamber shaped like a snail shell, where sound is transformed to nerve signals for the brain, and 3 semi-circular canals that function like a gyroscope, relaying information about head position and movement to the brain. The semicircular canals contain fluid and special sensors that, when disturbed, inform the brain of a change in head position.

Vertigo is a classification under dizziness that results in a spinning sensation or illusion of movement. (Many people who experience dizzy sensations often do not have vertigo, but instead, are found to have the common lightheadedness). Vertigo arises from disturbances in the vestibular system or neural structures such as the cerebellum, the brain stem, and the proprioceptive fibers along the spine.

Vertigo is a type of dizziness felt as a shift in a person's relationship to the normal environment (a feeling that the room is spinning is common) or a sense of movement in space. Although dizziness and vertigo are often used interchangeably, they are not the same thing. While all vertigo is dizziness, not all dizziness is vertigo. True vertigo, from the Latin "vertere," to turn, is a distinct, often severe form of dizziness that is a movement hallucination.

Vertigo, or a spinning sensation, is the main symptom. The sensation often starts suddenly and can be triggered by head movement. Most often, affected patients complain of the inability to roll in bed or to look up high at something. When severe, the vertigo is often accompanied by vomiting. Patients may also have visual complaints, such as a perception that things are jumping or moving.

Vertigo is a symptom, not a disease. The term vertigo refers to the sensation of spinning or whirling that occurs as a result of a disturbance in balance (equilibrium). It also may be used to describe feelings of dizziness, lightheadedness, faintness, and unsteadiness. The sensation of movement is called subjective vertigo and the perception of movement in surrounding objects is called objective vertigo.

If your dizziness is a symptom of medications you have taken in the past, it is important to avoid these in the future, if possible. Be sure that you tell each of your health care providers about all of the medicines you are taking, including over-the-counter medications, vitamins, and herbal remedies. It is important to avoid the use of drugs that may cause further damage the cells in your ear.

Many diseases can cause dizziness, especially diseases that involve poor circulation and low blood pressure. The first step of a diagnosis is a complete medical check-up. Audiometry is a thorough test of various hearing abilities. A device that measures eye movements in various situations, an electronystagmograph, provides clues about the nature of the problem. In platform posturography, you stand on a movable platform and your responses to movement are recorded.