Tourette's Disorder

Tics are abrupt, purposeless, and involuntary vocal sounds or muscular jerks. They are sudden, rapid, and recurrent. They can involve any body part and may vary in severity—from very mild and hardly noticeable to very disrupting, frequent, and severe.

Nearly 10 percent of school-aged children experience transient tic disorder—the most common type of tic disorder, with symptoms lasting at least 4 months, but no longer than one year. Symptoms of transient tic disorder may be more prevalent in periods of stress, fatigue, or as a result of certain types of medications, and may be confused with other symptoms of nervousness, anxiety, or restlessness that many children experience.

Tics which are seen lasting more than one year are classified as chronic tics. Chronic tics affect less than 1 percent of school-aged children and must be differentiated between Tourette's disorder in which multiple motor tics and at least one or more vocal tics must be present.

Tic disorders are generally differentiated based on the type of tics presented, the age of onset of symptoms, and the duration of symptoms.