Tourette's Syndrome

A treatable neurological disorder that consists of involuntary "tic" movements or vocalizations that become more apparent under stress. Common manifestations include shoulder-shrugging, neck-jerking, facial twitches, coughing, grunting, throat clearing, sniffing, snorting, and barking. Children with Tourette's often have problems with hyperactivity as well.

Source: Children Welfare Information Gateway