Tourette syndrome — also called Tourette's syndrome, Tourette's disorder, or Gilles de la Tourette syndrome — is a neurological or neurochemical disorder characterized by tics: involuntary, rapid, sudden movements or vocalizations that occur repeatedly in the same way. more...
The eponym was bestowed by Jean-Martin Charcot after and on behalf of his resident, Georges Gilles de la Tourette, (1859 - 1904), French physician and neurologist.
Symptoms include multiple motor and one or more vocal tics present at some time during the disorder although not necessarily simultaneously; the occurrence of tics many times a day (usually in bouts) nearly every day or intermittently throughout a span of more than one year; the periodic change in the number, frequency, type and location of the tics, and in the waxing and waning of their severity; symptoms disappearing for weeks or months at a time; and onset before the age of 18.
Vocal tics may fall into various categories, including echolalia (the urge to repeat words spoken by someone else after being heard by the person with the disorder), palilalia (the urge to repeat one's own previously spoken words), lexilalia (the urge to repeat words after reading them) and, most controversially, coprolalia (the spontaneous utterance of socially objectionable or taboo words or phrases, such as obscenities and racial or ethnic slurs). However, according to the Tourette Syndrome Association, Inc., only about 10% of TS patients suffer from this aspect of the condition. There are many other vocal tics besides those categorized by word repetition: in fact, a TS tic can be almost any possible short vocalization, with common vocal tics being throat clearing, coughing, sniffing, grunts, or moans. Motor tics can be of an endless variety and may include hand-clapping, neck stretching, shoulder shrugging, eye blinking, and facial grimacing.
The term "involuntary" has been used to describe TS tics, since it is known that most people with TS do have limited control over the expression of symptoms. Immediately preceding tic onset, individuals with TS experience what is called a "premonitory urge," similar to the feeling that precedes yawning. The control which can be exerted (from seconds to hours at a time) may merely postpone and exacerbate the ultimate expression of the tic. Children may be less aware of the premonitory urge associated with tics than are adults, but their awareness tends to increase with maturity. Tics are experienced as irresistible (like a yawn or sneeze or itch) and must eventually be expressed. People with TS often seek a secluded spot to release their symptoms after delaying them in school or at work. It is not uncommon for children to suppress tics during a visit to the doctor or while at school. Typically, tics increase as a result of tension or stress (but are not solely caused by stress) and decrease with relaxation or concentration on an absorbing task. In fact, neurologist and writer Oliver Sacks has described a man with severe TS who is both a pilot and a surgeon.
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