The Gilles de la Tourette syndrome (TS) is a chronic neuropsychiatric disorder that involves involuntary movements and vocal noises, called tics, which come and go. In addition to tics, individuals with TS often have a variety of other conditions which can include obsessive-compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), learning difficulties and sleep abnormalities. Although these conditions are not required for the diagnosis of TS, their impact on the patient may be more significant than the tics themselves. There is no diagnostic laboratory test. Diagnoses are based on the history and clinical examination of the patient.
Tics, the essential component of the syndrome, are manifested in a variety of forms with different durations and degrees of complexity. No two patients have exactly the same symptoms.
- Simple motor tics are brief rapid movements that often involve only one muscle group, e.g., eye blink, head jerk or shoulder shrug.
- Complex motor tics are abrupt movements that involve either a cluster of simple movements or a more coordinated sequence of movements. Complex motor tics may be non-purposeful (facial or body contortions), or appear to be more purposeful but actually serve no purpose (touching, smelling, jumping, obscene gestures), or have a dystonic character.
- Simple vocal tics include such sounds as grunting, barking, yelping and throat clearing.
- Complex vocal tics include syllables, phrases, echolalia (repeating other people's words), palilalia (repeating one's own words) or coprolalia (obscene words).