Tourette syndrome (TS) is a neurological disorder characterized by repetitive involuntary movements and vocalizations called tics.
The associated symptoms and signs of Tourette syndrome include tics referred to as either simple or complex. Simple tics are sudden, short repetitive movements like eye blinking, eyelid twitching, head or shoulder jerking, or grimacing. Other symptoms of simple tics can include repetitive throat clearing, sniffing, or grunting sounds. Complex tics are patterns of movements in which several muscle groups work together to produce the sign or symptom, such as hopping or jumping. Other types of complex tics may include repetition of certain words or phrases, sometimes swearing involuntarily and uncontrollably.
Causes of Tourette syndrome
The exact cause of Tourette syndrome is unknown. The condition often occurs together with other neurologic or behavioral conditions including attention deficit hyperactivity disorder (ADHD) or obsessive-compulsive symptoms and signs.
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.