What is stroke?

A stroke occurs when the blood supply to an area of the brain is cut off. The symptoms depend upon the region of the brain that is affected by the loss of blood supply and can include changes in sensation or motor control.

Symptoms of a stroke also depend on how much of the brain tissue is deprived of blood supply. For example, someone who had a mild stroke may experience temporary weakness of an arm or leg, but those with a more severe stroke may be permanently paralyzed on one side of their body or be unable to speak. If the blood supply is not quickly restored, either on its own or via medical treatment, the effects may be permanent.

A transient ischemic attack, or TIA, is sometimes referred to as a "mini-stroke." With a TIA, the stroke symptoms occur but go away on their own.

Some people fully recover completely from strokes, but over 2/3 of stroke survivors are left with some type of disability.