Tic Disorders: What Are They?
This disorder is characterized by tics, which are sudden, rapid, recurrent motor movements or vocalizations. If a child has both motor and vocal tics, he is diagnosed with Tourette’s disorder; if he has only motor tics or vocal tics, but not both, he is diagnosed with chronic motor or vocal tic disorder. Transient tics are common over the course of development. It is their persistence that raises concern. To meet criteria for a chronic tic disorder, the tics must persist in one form or another for more than a year. Onset must be before 18 years of age.