In 1885 George Gilles de la Tourette, a Parisian neuropsychiatrist, described nine patients with a chronic disorder characterized by the presence of multiple motor and vocal tics. He recognized many of the salient clinical features of the syndrome that today bears his name, including its onset in childhood, the tendency of tics to wax and wane, and the presence of a variety of comorbid neurobehavioural problems such as obsessive–compulsive symptoms, anxieties, and phobias. Nevertheless, Gilles de la Tourette (1885) and his mentor Charcot attributed this disorder to a form of ‘hereditary insanity’ and felt it was a degenerative disorder with ‘no hope of a complete cure’. Today, Tourette syndrome (TS) is considered a complex neuropsychiatric disorder with a wide spectrum of behavioural manifestations and psychological comorbidities.

Clinical features

Tics are the cardinal feature of TS. They encompass a wide variety of involuntary movements and sounds and are formally defined as involuntary, sudden, rapid, brief, repetitive, non-rhythmic stereotyped movements or vocalizations. Motor tics consist of involuntary movements and are subdivided into simple and complex subtypes. Simple motor tics are movements of single muscle groups. Examples include eye blinking, head jerking, and facial twitching. Complex motor tics consist of a coordinated pattern of movements that may be non-purposeful (facial or body contortions) or appear to be more purposeful but actually serve no purpose (touching, smelling, jumping, obscene gestures). Copropraxia describes the presence of obscene gestures, whereas echopraxia is the imitation of the gestures of others as a tic manifestation. Phonic (vocal) tics involve the production of sound. Simple phonic tics include sniffing, grunting, and throat clearing. Complex phonic tics involve the production of partial or complete words, phrases, or sentences. Palilalia is the repetition of one's own words and echolalia is the repetition of words of another person. Coprolalia is a dramatic type of tic that consists of the involuntary utterance of obscene words and phrases. Although once considered necessary for the diagnosis of TS, coprolalia occurs in only a small minority of patients with TS (Goldenberg et al., 1994). Tics are commonly misdiagnosed as other problems such as chronic respiratory symptoms, visual problems, asthma, allergies and anxiety.