The experience of a stroke is disorienting and frightening. Some people have a panic attack at the onset of symptoms, while others are simply confused by what is happening to them. The most common physical feelings are numbness or tingling in an arm, leg, or one side of the face. In more severe cases, the speech center of the brain can be affected, which may make speech difficult or impossible to understand. In other instances, vision may become strange with visual hallucinations, blurriness, or a sudden onset of blindness. Walking may become difficult if the leg muscles are affected. The most important thing to do is remain calm, sit or lie down, and call 911 (or the emergency number in your area).