A stroke is a "brain attack". It can happen to anyone at any time. It occurs when blood flow to an area of brain is cut off. When this happens, brain cells are deprived of oxygen and begin to die. When brain cells die during a stroke, abilities controlled by that area of the brain such as memory and muscle control are lost. How a person is affected by their stroke depends on where the stroke occurs in the brain and how much the brain is damaged. For example, someone who had a small stroke may only have minor problems such as temporary weakness of an arm or leg. People who have larger strokes may be permanently paralyzed on one side of their body or lose their ability to speak. Some people recover completely from strokes, but more than 2/3 of survivors will have some type of disability. Stroke by the Numbers Each year nearly 800,000 people experience a new or recurrent stroke. A stroke happens every 40 seconds. Stroke is the fifth leading cause of death in the U.S. Every 4 minutes someone dies from stroke. Up to 80 percent of strokes can be prevented. Stroke is the leading cause of adult disability in the US .