Tic Disorders and Tourette’s Syndrome

What are Tics?  

Tics are short-lasting repetitive muscle movements that may involve any voluntary muscle groups and occur suddenly during what is otherwise normal behavior.  Most tics are mild and hardly noticeable. However, in some cases they are frequent and severe, and can affect many areas of an individual’s life.  With tics a part of the body moves repeatedly, quickly, suddenly and uncontrollably.  Despite this, they can be stopped or partially controlled for brief periods of time, during which an individual makes a strong effort to control them.   However, after some time the tics will reoccur and may be stronger as a result of having held them back.  Think of a tic as resulting from an internal pressure or itch at the location of the where the tic will occur.  This grows in intensity until the tic is released.  Imagine if you felt the need to sneeze and without touching your nose you would try to prevent yourself from doing this.  How long could you go without sneezing?  This is how a person with a tic disorder feels constantly.  Additionally, while no one knows exactly what causes tics to occur, it is known that tics become worse when people are under stressful situations or just escaped one.  Basically, anything that causes excitement, good or bad, can bring out tics.  In addition to stress, sleep deprivation seems to play a role in both the occurrence and severity of motor tics.  Tics usually fluctuate in intensity and are often temporary.  It is only when they occur with increased frequency that they qualify for a specific tic disorder.

What are the Different Types of Tics?

There are two kinds of tics.  There can be vocal tics, motor tics or a combination of both.  Motor Tics can include the hands, arms, shoulders, legs, face, neck, mouth, eyes and nose.  Vocal Tics can include throat clearing, grunting sounds, coughing sounds, sniffing sounds or basically any sound, produced by the mouth, throat, or nose.   In addition to this, tics can be simple or complex.  Simple Vocal Tics  are purposeless and can include humming, grunting, or any other sound.  They usually occur in a spastic explosive fashion and at times are out of context to what is being discussed, such as an odd sound inserted into the middle of a sentence.  Simple Motor Tics can include, but are not limited to eye blinking, nose twitching, head-jerking, shoulder-shrugging, facial grimacing, mouth opening or nasal flaring.  A Complex Vocal Tic is one that actually produces a word, not just a sound.  They can include bad words (coprolalia).  Complex Motor Tics consist of a series of muscle movements performed with a purpose, such as scratching, throwing, or chewing.  A person with a complex motor tic might reach out and touch something repeatedly or kick out with one leg and then the other.  Finally, tics can be transient or chronic.  While Transient Tics disappear within a year, Chronic Tics can last for a year or more.  Chronic tics affect less than one percent of children and may be related to a special, more unusual tic disorder called Tourette’s Disorder.

What is the Difference Between Tics and Twitches?

It is important to note that while many people interchange the words tic and twitch, there are significant differences between these two forms of movements.  Unlike tics, the majority of muscle twitches occur rarely and are not repetitive actions. Muscle twitches are also known as myoclonic jerks. They are entirely involuntary and cannot be controlled or suppressed.  Many people experience these spastic movements of particular muscles at some point.  They often affect the eyelids or face, but can occur anywhere in the body.  In most instances they are harmless and temporary.  While an eyelid twitch may mimic an eye-blinking tic, it is different because it cannot be controlled.  However, they can be aggravated by having dry eyes or worsened by stress, lack of sleep, caffeine, and harsh light conditions.

How Common are Tic Disorders and Tourette’s Syndrome?

While people of all ages can experience tics, they are most common in children.  In fact, experts say that around 25% of children can experience tics and they are much more likely to affect boys than girls.  For instance, Tourette’s syndrome is three times more common in boys than in girls.  Tic symptoms typically begin when children are between 5 and 18 years old.  They are generally most severe between 10 and 12 years of age and decrease by adulthood.  Children who develop tics between ages 6 and 8 usually do very well.  Their symptoms may last 4 to 6 years, and then stop without treatment in early adolescence.  However, when the disorder begins in older children and continues into the 20s, it may become a life-long condition.  Some children are more susceptible than others.  Non-Hispanic white children were more than twice as likely as non-Hispanic black children or Hispanic children to have a parent-reported case of Tourette’s syndrome.  According to the CDC, those with chronic tics including Tourette’s syndrome include about one in 100 people and three out of every 1,000 children between ages 6 and 17 in the United States.  It is estimated that 200,000 people in the U.S. are living with Tourette’s syndrome, though many people with the disorder have not been diagnosed.  Twenty-seven percent of children with Tourette’s syndrome have moderate or severe cases and 79% of those diagnosed with Tourette’s also have been diagnosed with at least one additional mental health or Neurodevelopmental condition, including higher rates of attention deficit/hyperactivity disorder, obsessive-compulsive disorder, and impairments associated with these conditions, such as learning disabilities and problems with peer relations.

Do Tic Disorders Have a Genetic/Biological Component?

The exact cause of tic disorders, such as Tourette’s syndrome, is unknown.  However, it is thought that Tic Disorders are transmitted in an autosomal dominant manner, but other genetic factors may play a role.  These include gene amplification (worsening effects in affected individuals through consecutive generations) and genetic imprinting (having a different presentation whether the gene is inherited from the mother’s or father’s chromosomes).   Additionally, Tourette’s syndrome may be more likely to occur in children whose mothers drank alcohol, drank caffeine, smoked, or suffered extreme stress during pregnancy.  Children with low birth weights may also be more likely to develop tics and Tourette’s syndrome.

How are Tic Disorders Diagnosed?

It is important to keep in mind that the majority of tics are not severe and have very little effect on an individual’s quality of life. However, in some instances tics can occur frequently enough to be very disruptive and troubling. When this occurs, they can affect several areas of a person’s life, including school, work, and social life.  In diagnosing tic disorders, doctors use four characteristics to identify and diagnose the various types:  1) the age when the tics began; 2) the duration of the tics; 3) the severity of the tics and 4) whether the tics are motor, vocal, or both.

What are the Types of Tic Disorders?

Transient Tic Disorder most commonly appears in kids and affects between 5% and 25% of school-age children. Transient tic disorder is the most common of the tic disorders.  It is characterized by the presence of one or more tics for at least one month, but less than one year. It may affect up to 10 percent of children during the early school years. The majority of tics seen in this disorder are motor tics, though vocal tics may also be present.  Many children with this disorder experience multiple episodes of the transient tics, which may vary in how they manifest over time and eventually go away by themselves.  Some may get worse with anxiety, tiredness, and some medications.

Chronic Motor or Vocal Tic Disorder is characterized by the presence of one or more long-lasting tics.  It involves quick, uncontrollable movements or vocal outbursts (but not both).  For the diagnosis of a chronic tic disorder, the symptoms must begin before a child is 18 years of age.  About 1 to 2% of the population has a chronic motor tic disorder and this is the second most common of the tic disorders.  The tics can even occur during all stages of sleep. They may get worse with excitement, fatigue, heat or stress.  Keep in mind that in some instances, what appears to be a chronic tic may be a sign of Tourette’s syndrome.  Tourette’s syndrome is the most severe tic disorder. It is characterized by the presence of both motor tics and vocal tics.

Tourette’s Syndrome or Tourette’s disorder is the most complicated and concerning of the tic disorders. It is a combination of both vocal and motor tics that must be present for at least 1 year and never stop for longer than 2 months at a time. The vocal and motor tics may occur at the same time, but don’t have to in order to qualify for the diagnosis of Tourette’s.  They also must be causing a significant impairment in the individual’s life.  Tourette’s disorder has a fluctuating course and the severity of the symptoms often changes over time.  There may be periods of reduced tic frequency followed by increased tic activity. Fortunately, many people with Tourette’s syndrome find that their condition improves, as they get older.  The usual presentation of Tourette’s disorder may include hyperactivity and irritability. At this time some kids may be diagnosed with ADHD and started on stimulant medication, which may be discontinued later as tics develop. The tics usually evolve, initially involving motor tics in the face area, such as eye blinking, facial grimacing, hair fixing, mouth opening, nasal flaring, and neck jerking. The tics then move to the shoulders and extremities. Usually the vocal tics develop later and frequently consist of throat clearing. Other vocal tics may consist of humming sounds, grunting, high-pitched noises, yelling, and actual words including occasional profanity.  For the most part, those with Tourette’s cannot control these sounds and movements and should not be blamed for them. Punishment by parents, teasing by classmates, and scolding by teachers will not help the child to control the tics but will hurt the child’s self-esteem and increase their distress.  The full-blown condition may be extremely disruptive and living with it may be difficult.  Additionally, obsessive-compulsive behaviors, anxiety, and depression may be associated with Tourette’s and, if not present at initial presentation, may develop later into the course of the disorder.

Tic Disorder Not Otherwise Specified includes all the other tic disorders that do not