Paralysis Stroke

Strokes are the number one cause of paralysis. A stroke is when an inadequate supply of oxygen to the brain results in damaged brain tissues and vessels. This event is caused by a blood clot or a ruptured artery and paralysis, weakness, sensory change, speech defect and/or death may occur. Some of the risk factors include: high blood pressure, high cholesterol, smoking, and diabetes.

A stroke causes paralysis because of the damage done to an area of the brain. Because of the this the damaged area of the brain is not able to send out the signals to the nerves that tell the muscles what to do.
 Paralysis Definition

Why does a stroke cause paralysis in different parts of the body.

Nerve cells in the brain tissue communicate with other cells to control such functions as memory, speech, and movement. When a stroke happens, nerve cells in the brain tissue become injured. As a result, they cannot communicate with other cells, and functions are impaired. If a stroke occurs on the right side of the brain, the left side of the body is affected, and vice versa.  Information from Cleveland Clinic