What are tic disorders?
A tic is “… a sudden, rapid, recurrent, nonrhythmic motor movement or vocalization” (DSM-5). There are two primary types of tics: motor tics (involving movements of the body) and vocal tics (producing words or sounds). Tourette Syndrome (TS) is diagnosed when an individual has multiple motor tics and at least one vocal tic. Chronic tic disorder (CTD) is diagnosed when an individual has either motor tics or vocal tics, but not both.For both disorders, the tics occur multiple times per day, must begin before the age of 18, and last for at least one year. The tics must also cause the person a significant amount of distress and impairment in his or her life.
What causes tics?
We do not know exactly what causes tics. We do know that there is a genetic component, but that is certainly not the only cause, and researchers are learning more about systems in the brain and abnormalities in specific neurotransmitters (e.g., dopamine). Additionally, there are likely both internal (cognitive/emotional) and external (social/environmental) factors that contribute to the tic expression in a person vulnerable to developing them. Certain kinds of situations or experiences can trigger tics for a person with TS, like being upset or anxious, being in crowds, being alone, experiencing stressful life events, or even just talking about tics. The situations that will trigger tics vary between people.
How common are tics?
Tics are much more common in children compared to adults, and they most often begin between 5 and 7 years of age. For many individuals, their tics will increase through early adolescence but then subside as they grow older, often disappearing entirely by adulthood. However, for about 25% of people who have tics as a child, the tics persist into adulthood. It is also common for tics to wax and wane over time, with some periods being characterized by more intense and frequent tics than others. The type of tics that a person engages in can also change over time.
Are tics involuntary?
Researchers believe that tics are neither completely involuntary nor always under the individual’s control. Tics are usually preceded by what is called a ‘premonitory urge’— meaning that the individual will experience a growing tension, pressure, or urge to tic right before they actually do. Performing the tic will bring about a feeling of relief or a reduction in tension. In this sense, people often feel the need to tic and know they are about to do it, but find it extremely difficult to control.
Treatment for Tourette Syndrome and Chronic Tic Disorder
Therapy for Tourette Syndrome and Chronic Tic Disorder can be a good option, particularly for those who prefer not to take medication. Growing evidence suggests that Habit Reversal training (HRT), a type of behavioral therapy, is an effective treatment for TS/CTD. In HRT, the therapist teaches the individual strategies for becoming aware of the urge to tic and for engaging in a different physical response (a competing response) that is physically incompatible with the original tic. There are several major components typically included in habit reversal training: psychoeducation, awareness training, competing response training, functional interventions, and relaxation training. HRT is generally brief in duration—patients are often able to see reductions in the frequency and severity of their tics within a few months of HRT. For continued improvements, however, individuals must commit to engaging in the practices and completing homework even after the treatment has ended.
It is always best to consult with a doctor regarding medication recommendations. For individuals with mild tic symptoms, medication may not even be necessary—therapy, psychoeducation, and support may be enough. For individuals who have more significant tic symptoms causing distress, interference, or impairment, medication may be helpful.
There are several different kinds of medication that can be prescribed to reduce the frequency and severity of tic symptoms. The effects of each kind of medication will vary from individual to individual, so there is no one “best” medication. For individuals with mild to moderate tic symptoms, guanfacine (Tenex) or clonidin (Catapres) are often prescribed. These drugs are also prescribed to treat anxiety and panic disorders. For individuals who have tic symptoms that fall in the moderate to severe range, neuroleptics are often prescribed, such as the newer atypical neuroleptic risperidone (Risperdal) or a traditional neuroleptic such as haloperidol (Haldol).
For more general information regarding treatment, please read our Treatment Approaches page on our website.
How CORD can help:
Our center specializes in evidence-based treatment for tics with therapy and medication. For more information, please contact:
If you are interested in learning more about our studies, please contact us at CORDResearch@mgh.harvard.edu.