Autism and Tic Disorders

An interview with Samuel Zinner, MD.

Sometimes we at Seattle Children’s Autism Center get questions or concerns from parents about some of the unusual mannerisms children with autism display. In an earlier blog post, we discussed many of these behaviors and why our kids do these things. One question (not covered in that post) we often hear is this: “Is what I’m seeing a tic?” when it comes to repetitive vocalizations or motor movements.

To answer this question, we turned to an expert on tic disorders, Samuel Zinner, MD. Dr. Zinner is an associate professor of pediatrics and a developmental-behavioral pediatrician at the University of Washington and Seattle Children’s Hospital. His research, advocacy and clinical interests focus on tic disorders and associated conditions including Autism Spectrum Disorders.

According to Dr. Zinner, tics are a semi-voluntary or voluntary response to involuntary sensation.

One way to think of it is like this:

There is an URGE (involuntary sensation), the TIC occurs (the semi-voluntary or voluntary response) and then there is RELIEF.

Dr. Zinner explains, “If you ask a person with a tic disorder, they can describe an unpleasant urge/sensation right before the tic occurs.”

To help us understand the pattern of a tic, Dr. Zinner gave a good example we all can relate to – trying not to blink. As time passes, an urge is building and you are thinking “I want to blink!” That urge is going to build and remain there until it is relieved. In this case, a blink brings relief.”

That is a very simple description of a pattern of a tic, but for people that suffer from tic disorders, it isn’t as easy as a blink. Often the urge will increase in intensity until it can no longer be ignored, which can be embarrassing in social situations, especially when the person is trying to hold it in. Tics must be performed and completed in a satisfying enough way to diminish the urge and are reinforced by the relief associated with successful completion of the tic. Essentially, performing the tic reinforces it.

Tics are not the same as compulsions, habits, or stereotypies (repetitive or ritualistic movements, postures, or utterances) which we often see in autism.

However it is possible and not uncommon for someone to have a tic disorder and one of the other three as well. A point of difference is there is not a sense of urge or relief associated with the other three when they are completed.

Types of tic disorders:

Tourette Syndrome

Both verbal tics (also known as phonic tics) and motor tics, affects  1% of the population

Chronic Motor Tic Disorder

Verbal or motor tics, occurs for at least 1 year, more common than Tourette’s, affects approximately 1 in 50 people

Transient Motor Tic Disorder

Verbal or motor tics that come and go, don’t return and duration is less than one year

Can a child with autism also have a tic disorder?

Yes. What we know of tic disorders is they are highly genetic and neurodevelopmental in nature. They are also more common in males than females. They are also known to be related to behaviors related to anxiety. Some of the physiology that we do know about tics is that there is an imbalance in dopamine and other brain chemicals in very specific circuits in the brain of a person affected by a tic disorder. The basal ganglia, in particular, has been identified in both tic disorders and autism.

What are the options for tic management?

• Manage anxiety and/or depression first (since these disorders can increase tics)
• Manage ADHD (since treating ADHD can help decrease impulsivity)
• Educate family and the individual about tics (understand that it is the nature of tics for them to wax and wane- have patience!)

If a parent has concerns about possible tics they should talk with their pediatrician, who may refer them to a neurologist or neurodevelopmental pediatrician. It is also helpful to describe your child’s behaviors rather than just saying they have a tic. Tics are very unique to the individual experiencing them. It is important to note that there is no blood analysis, x-ray or other medical test that can identify this condition. Diagnosis is made by observing symptoms and evaluating a person’s history.

Resources

For more information and resources related to Tic Disorders please see tsa-usa.org.