Tics are rapid, purposeless, repetitive but not rhythmic, involuntary movements (muscle or motor tics) or involuntary, abrupt, often repetitive sounds and/or words (vocal tics). They can be suppressed but only for a short time and only with conscious effort. Tourette syndrome is diagnosed when people have had both motor and vocal tics for more than a year.
The urge to blink, grimace, jerk the head, move in some other way, or make a sound is irresistible, and the action is not voluntary.
Doctors base the diagnosis on symptoms.
Many tics disappear on their own, but if they are troublesome or severe, Comprehensive Behavioral Intervention for Tics and sometimes medications may help.
Tics vary widely in severity, and are common among children.
Many tics are mild and often are not recognized as a disorder by parents and doctors.
Tics are 3 times as likely to occur in boys as in girls.
Tourette syndrome is the most severe type of tic disorder and occurs in 3 to 8 of 1,000 children.
Tics begin before age 18 years (typically between ages 4 years and 6 years), increase in severity to a peak at about age 10 to 12 years, and decrease during adolescence. Eventually, most tics disappear. However, in about 1% of children, tics persist into adulthood.
Children with tics may have other disorders such as
These disorders often interfere more with children's development and well-being than the tics. Sometimes tics first appear when children with ADHD are treated with a stimulant medication such as methylphenidate. These children probably have an underlying tendency to develop tics.
Adolescents (and adults) with tics may also have
Classification of Tic Disorders
There are three major types of tic disorder:
Provisional tic disorder: Children have had motor and/or vocal tics for less than a year.
Persistent tic disorder (chronic tic disorder): Children have had motor or vocal tics (but not both) for more than a year.
Tourette syndrome: Children have had both motor and vocal tics for more than a year.
Typically, children begin with provisional tic disorder and sometimes go on to develop persistent tic disorder or Tourette syndrome.
Causes of Tic Disorders
The cause of tic disorders is not known, but tic disorders often run in families, so doctors think heredity plays a part.
Sometimes people who have another disorder, such as Huntington disease or a brain infection (encephalitis
In children who have or have had a streptococcal (strep) infection, tics and/or symptoms of OCD sometimes start suddenly or become dramatically worse within a day. Such cases are called pediatric autoimmune neuropsychiatric disorder associated with streptococcus (PANDAS). Some investigators think that antibodies produced by the body to fight the streptococcal bacteria may cause tics (or OCD) or make tics worse. However, most investigators think that the proof of this connection is lacking.
Symptoms of Tic Disorders
Before a tic occurs, an urge to do the tic may be felt. This urge is similar to the need to sneeze or scratch an itch. Tension builds up, usually in the affected body part. Giving in to the tic provides brief relief.
The tic can sometimes be postponed for seconds to minutes but only with conscious effort and difficulty. Usually, the urge to do the tic eventually becomes irresistible. Trying to control tics is usually difficult, especially during times of emotional stress. Stress and fatigue can make tics worse. However, tics often also become worse when the body is relaxed, as when watching TV. Calling attention to a tic, particularly in children, may make the tic worse. Typically, tics do not occur during sleep, and they rarely interfere with coordination. Tics may lessen when people are concentrating on a task such as school or work activities or when people are in an unfamiliar place.
People with severe tics, particularly Tourette syndrome, may have difficulty functioning and experience considerable anxiety in social situations. In the past, they were shunned, isolated, or even thought to be possessed by the devil. They may become impulsive and aggressive and behave in self-destructive ways.
Children with a severe tic disorder or Tourette syndrome are more likely to have another disorder, such as OCD, ADHD, and/or learning disorders. These problems seem to result from the brain abnormalities that cause tics and Tourette syndrome. However, when a tic disorder is severe, the extraordinary stresses of living with the disorder may make these problems worse.
Tics tend to be similar at any given time, but they vary in type, intensity, and frequency over a period of time. Sometimes they start suddenly and dramatically. They may occur several times an hour, then almost disappear for many months.
Types of tics
Tics may be
Simple or complex
Motor, vocal, or both
Simple tics are extremely brief. They may begin as nervous mannerisms.
Complex tics last longer and may combine several simple tics. In some complex tics, people may call out socially inappropriate words, such as obscenities or words related to feces (called coprolalia). Although people often associate coprolalia with Tourette syndrome, at least 85% of people with Tourette syndrome do not have coprolalia. Complex tics may appear intentional, as in coprolalia or when a person repeats another person's movements or words, but they are not.
Types of Tics
Type | Motor | Vocal |
|---|---|---|
Simple | Blinking Grimacing Head jerking Shoulder shrugging | Grunting or barking Sniffing or snorting Throat clearing |
Complex | Combinations of simple tics (such as head turning plus shoulder shrugging) Copropraxia: Using sexual or obscene gestures Echopraxia: Imitating someone's movements | Coprolalia: Uttering socially inappropriate words (such as obscenities or ethnic slurs) Echolalia: Repeating one's own or another's sounds or words |
Did You Know...
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Diagnosis of Tic Disorders
A doctor's evaluation
Early diagnosis of a tic disorder can help parents understand that the tics their children have are not intentional and that punishment cannot stop the tics and may even make them worse.
The diagnosis is based on the symptoms and their duration.
To distinguish Tourette syndrome from other tic disorders, doctors may have to evaluate children periodically over time.
Doctors also check children for disorders that often accompany tics, such as ADHD and OCD.
Treatment of Tic Disorders
Reassurance and support
Comprehensive Behavioral Intervention for Tics
Medications
If symptoms are mild, reassurance is often best, with as little attention paid to the tic as possible until it disappears on its own. Treatment can often be avoided if the family understands the disorder and if the disorder is explained to and understood by the child's teachers and schoolmates.
Comprehensive Behavioral Intervention for Tics (CBIT)
CBIT is a type of behavioral therapy. It may help some older children manage their tics.
CBIT includes the following:
Cognitive-behavioral techniques (such as habit reversal training)
Education about tics
Relaxation techniques
Habit reversal training involves teaching children new behaviors to substitute for the tics. For example, if the tic involves shrugging their shoulders, they may be taught to stretch out their arms until the urge to shrug passes.
Education may involve teaching children (and their parents) to identify situations in which tics occur or become worse.
Medications
Medications to stop tics are recommended only if tics persist and are interfering with the child's activities or self-image. The lowest dose needed to make tics tolerable is used, and doses are decreased as tics lessen.
For mild tics,clonidine can cause drowsiness, which may interfere with the child's daytime activities. Although clonidine is also used to treat high blood pressure, it rarely causes low blood pressure in children. However, after children have taken clonidine for a while, suddenly stopping clonidine may cause blood pressure to increase temporarily.
For severe or difficult to control tics, antipsychotic medicationsparkinsonism), and tardive dyskinesia, which is repetitive, slow, involuntary movements. However, these side effects are rare because the doses used to treat tics are low.
Treatment of other problems
Children who have tics and who are struggling in school should be evaluated for learning disorders and provided with support as needed.
If obsessive or compulsive traits are bothersome, a medication such as a selective serotonin reuptake inhibitor (SSRI), which is an antidepressant, may be useful.
ADHD can be difficult to treat because the stimulant medications typically used to treat it may worsen tics. Sometimes low doses of these medications can effectively treat ADHD without making tics worse. Or a medication that is not a stimulant can be used to treat ADHD.
