A disorder of the nervous system that causes a person to make repeated and uncontrolled movements and sounds called tics. People with this condition may twitch, shrug their shoulders, blink, jerk their head, utter grunts or make strange sounds, or even to yell out curse words. About 1-2% of Americans have the disorder. Many children with Tourette's will outgrow the disorder. The symptoms appear in childhood and in about half disappear in the late teen years.