Every 40 seconds a stroke occurs in the United States, but most don't know what to look for and how to respond, a non-profit group says. The American Heart Association/American Stroke Association and the Ad Council began a national multimedia public service advertisement campaign to raise awareness about F.A.S.T. -- an acronym to recognize and respond to the sudden warning signs of stroke. F.A.S.T. is designed to help bystanders spot a stroke fast because the quicker a stroke victim receives medical attention, the greater his or her chances of survival and a better recovery. F.A.S.T. stands for: -- Face Drooping: Does one side of the face droop or is it numb? Ask the person to smile. -- Arm Weakness: Is one arm weak or numb? Ask the person to raise both arms. Does one arm drift downward? -- Speech Difficulty: Is speech slurred? Are they unable to speak, or are they hard to understand? Ask the person to repeat a simple sentence like: "The sky is blue." Is the sentence repeated correctly? -- Time to call 9-1-1: If the person shows any of these symptoms, even if the symptoms go away, call 9-1-1 and get them to the hospital immediately. The American Stroke Association, a division of the American Heart Association, reported the quicker a stroke victim gets to a hospital, the quicker he or she can be assessed for a clot-busting drug that may reduce disability and death from stroke. The television, radio, print, outdoor and Web PSAs were created pro bono by advertising agency Grey New York.