Tic Disorders

Tic disorders are neurological ^* conditions characterized by sudden, rapid movements (for example, neck jerking) or sounds (words or other types of sounds, such as grunting or sniffing) that are repeated over and over in a consistent way many times a day.

What Are Tics?

Tics have been described as brain-activated "involuntary" movements or sounds, meaning that the person does not produce them intentionally. People with tics often can suppress them, sometimes for up to hours at a time, just as one might suppress a cough or a sneeze for a period of time. Imagine, for example, suddenly having to cough in the middle of a concert. To avoid interrupting the musicians, people might try very hard not to cough until the intermission. When they finally cough, however, they might cough several times instead of just once or twice. The experience of trying to suppress a tic is similar. After a tic is suppressed, it may erupt with even greater force or frequency.

Tics tend to get worse when people feel anxious or tired and get better when they are calm and focused on an activity. One interesting aspect of the condition is that tics usually lessen around strangers and are expressed more freely among family members and other trusted people. This does not mean that a person is producing the tics purposely around family members. It probably reflects the fact that they are working harder to suppress them in less comfortable situations, while it is natural for a person to relax their suppression when they are in more familiar surroundings. It is not uncommon for a child to be taken to a doctor to diagnose the problem, only to have the child be unable to produce tics "on command." Just as tics are experienced as uncontrollable, they cannot be voluntarily brought on. While tics may appear as early as 2 years of age, the average age at onset is about 7.

What Are the Symptoms of Tics?

Simple tics

Simple tics involve a single movement, such as eye blinking or repeatedly sticking out the tongue. Tics also may be vocal, made up of a single sound, such as throat clearing or snorting, stuttering, or sniffing. The most common type of tics, and often the first to appear, are simple facial tics. Over time, more complex motor ^* tics may appear.

Complex tics

Complex motor tics involve several coordinated muscle movements, such as touching or smelling an object, jumping or twirling, or making deep knee bends while walking. These tics may include neck stretching, foot stamping, body twisting and bending, or mimicking the gestures of other people. Complex vocal tics can range from combining "simple" throat clearing or grunting with other vocal behaviors, to repeating a long but meaningless string of words at regular intervals.

With complex tics, the repeated phrase or gesture at first may seem meaningful, even when it is not. For example, the person with a complex motor tic may feel a need to do and then redo or undo the same action several times (for example, stretching out one arm ten times before writing or retracing the same letter or repeating the same word) before proceeding to another activity. Such forms of behavior can interfere with a person's ability to accomplish school- or work-related tasks.

Researchers have identified more than 80 tics, which are a mix of simple and complex motor and vocal tics. Some recognizable tic patterns include:

• Echopraxia (EK-o-PRAX-ee-a): imitating other people's movements or gestures
• Copropraxia (KO-pro-PRAX-ee-a): making obscene, rude, or socially unacceptable gestures
• Palilalia (PA-li-LAY-lee-a): repeating a person's own words
• Echolalia (EK-o-LAY-lee-a): repeating someone else's words
• Coprolalia (KO-pro-LAY-lee-a): shouting obscenities, or impolite and offensive language
• Repetition: repeating words or phrases out of context (for example, "Look before you leap").

What Are Tic Disorders?

Doctors usually classify tic disorders into four categories: Tourette syndrome, chronic motor or vocal tic disorder, transient (TRAN-shent) tic disorder, and tic disorder (not otherwise specified).

Tourette syndrome

Tourette syndrome is the best known of the tic disorders, and it is characterized by a frequent and long-lasting pattern of both vocal and motor tics.

Chronic motor or vocal tic disorder

In contrast to Tourette syndrome, chronic ^* motor or vocal tic disorder involves only one of these two basic types of tics (either motor or vocal), but not both. In other respects, chronic tic disorder has many of the same symptoms as Tourette syndrome in that:

• The tics occur many times a day, nearly every day, and the condition lasts for more than a year.
• The tics may disappear for a time, but that period never exceeds more than 3 months in a row.
• The tics first appear before the age of 18.
• The tics are not the result of a medication or another medical condition.
• The tics cause significant impairment at school or work.

Transient tic disorder

In contrast to chronic motor or vocal tic disorder, transient tic disorder refers to a briefer problem with tics. Transient tics may be motor or vocal, or both. For a condition to be considered transient tic disorder, the tics must begin before age 18, occur several times a day, nearly every day for at least 4 weeks but for no longer than 12 months in a row. As with the other tic disorders, transient tics are not the result of another medical condition or a medication.

Tic disorder (not otherwise specified)

This is a category for tic disorders when they do not fit into any of the other three groups, usually because the tics last less than 4 weeks or because they begin when a person is older than 18.

How Are Tic Disorders Diagnosed?

While there are clear differences between tic disorders, a doctor may find it difficult to make a diagnosis, because tics often change in type or frequency over time. Transient tics, for example, are short-lived tics that last for less than a year. But a child may experience a series of transient tics over several years. Neck jerking may last for several months and then be replaced by finger snapping or stamping in place. Chronic tics, on the other hand, last longer than a year and tend to remain stable and constant over time.

Transient tics that change over time are believed to affect as many as one-fourth of all school-aged children. While they last, these tics may be quite odd. They might range from sticking out the tongue again and again to repeating a word or phrase a set number of times to poking or pinching various parts of the body. These strange kinds of behavior are more common than was once believed, but often they disappear as a child matures.

Distinguishing transient tics from chronic tics often requires careful evaluation by a physician over a period of years. In addition, it is important for a doctor to gather information about other members of the family (including parents, grandparents, and siblings) who also may have tics or related conditions. It is now known that the tendency for tics to develop is passed on genetically ^* (inherited) from generation to generation. Because a person may inherit the genetic tendency to tics without ever experiencing tics, it is possible for the disorder to skip several generations in one family. Research is under way to identify the specific gene (or genes) for tic disorders and to understand other factors that may influence whether a person at risk actually will experience tics.

Related Conditions

For most people who have tics, the real threat may not be the tics themselves but the sense of shame and social isolation that can result from this odd behavior. A child may have great difficulty dealing with these embarrassing, unwanted behaviors. It also may be hard for teachers, fellow students, and family members to understand that a person with tic disorder is not making these strange gestures and sounds intentionally, to gain attention or to avoid working. Other people can easily get that impression if the pattern of tics changes from day to day, as it often does. It can make matters even more difficult when tic disorders in children are associated with attention disorders, hyperactivity, impulsive behavior, obsessive-compulsive disorder ^* , irritability, or aggressiveness.

It is estimated that as many as half of the children with Tourette syndrome also have the attention and impulse-control problems that are seen in attention deficit hyperactivity disorder. Children with Tourette syndrome also have higher than average rates of learning disabilities that cause reading or language problems.

How Are Tics Treated?

There are several therapies to help children with tics cope with the frightening feelings of being out of control and with the specific types of behavior related to their condition. These include relaxation and stress-reduction techniques, and biofeedback. Often, medication is an important part of the treatment plan. Because of associated stress, anxiety, and self-esteem and relationship issues, working with a mental health professional when concerns begin to interfere with the quality of life is particularly important. A combination of treatment approaches is often required when tics and associated mental health problems are serious.