Dizziness is an impairment in spatial perception and stability. Because the term dizziness is imprecise, it can refer to vertigo, presyncope, disequilibrium, or a non-specific feeling such as giddiness or foolishness. One can induce dizziness by engaging in disorientating activities such as spinning. Vertigo is the sensation of spinning or having one’s surroundings spin about them. Many people find vertigo very disturbing and often report associated nausea and vomiting. It represents about 25% of cases of occurrences of dizziness. Disequilibrium is the sensation of being off balance, and is most often characterized by frequent falls in a specific direction. This condition is not often associated with nausea or vomiting. Presyncope is lightheadedness, muscular weakness and feeling faint as opposed to a syncope, which is actually fainting. Non-specific dizziness is often psychiatric in origin. It is a diagnosis of exclusion and can sometimes be brought about by hyperventilation. A stroke is the cause of isolated dizziness in 0.7% of people who present to the emergency room.