Tourette syndrome is an inherited neurological disorder beginning in childhood, characterized by multiple physical (motor) tics and at least one vocal (phonic) tic. These tics characteristically wax and wane, can be suppressed temporarily, and are preceded by a premonitory urge. Tourette Syndrome is a spectrum disorder with symptoms ranging from mild to severe. The expression of symptoms leading to the diagnosis of Tourette Syndrome is more common in males.
Comorbid conditions (co-occurring diagnoses other than Tourette Syndrome) such as Attention deficit Hyperactivity Disorder (ADHD) and Obsessive Compulsive Disorder (OCD) are common. These other conditions usually cause more functional impairment to the individual than the tics that are the hallmark of Tourette Syndrome.
Diagnosis of Tourette Syndrome
For a person to be diagnosed with Tourette Syndrome, he or she must:
- have both multiple motor tics (for example, blinking or shrugging the shoulders) and vocal tics (for example, humming, clearing the throat, or yelling out a word or phrase), although they might not always happen at the same time.
- have had tics for at least a year.
- have tics that begin before he or she is 18 years of age. The usually age for the emergence of tics is between 5-7 years of age.
- have symptoms that are not caused by a medication, drug or other medical condition
Tics are sudden, intermittent, unpredictable, repetitive, nonrhythmic movements (motor tics) and utterances (phonic tics) that involve discrete muscle groups. The wide range of tics or tic-like symptoms that can be seen in Tourette Syndrome is enormous. The complexity of some symptoms often confuses family members, friends, teachers and employers who may find it hard to believe that the actions or vocal utterances are “involuntary”. Tics also wax and wane that is increase and decrease in the severity and frequency of their occurrence.
Tics can be classified in the following ways.
Motor tics are movement-based.
Phonic (Vocal) tics are involuntary sounds produced by moving air through the nose, mouth, or throat.
Simple Tics involve small muscle groups. For example, some simple motor tics may be eye blinking, head jerking, shoulder shrugging and facial grimacing. Some simple vocal tics may be throat clearing, yelping, sniffing and tongue clicking.
Complex Tics are tics that consist of a series of movements performed in the same order. For example, some complex motor tics may be jumping, touching other people or things, smelling things, twirling and, although very rare, self-injurious actions including hitting or biting oneself. Complex vocal tics may be uttering ordinary words or phrases out of context, echolalia (repeating a sound or word or phrase just heard) and in rare cases coprolalia, (vocalizing socially unacceptable words).
Tics are temporarily suppressible and are often preceded by an unwanted premonitory urge. The premonitory urge can be likened to the need to sneeze or scratch an itch. Individuals may describe the need to tic as a buildup of tension, pressure, or energy which they consciously choose to release, as if they “had to do it” to relieve the sensation or until it feels “just right“. For example a premonitory urge may be the feeling of having something in one’s throat prior to a throat clearing tic or an uncomfortable sensation in the eye prior to a blinking tic. The tic may be felt as relieving the premonitory urge sensation much like scratching an itch. Premonitory urges are also not required for a diagnosis of Tourette Syndrome and some individuals may be unable to report any. This is especially true in young children. The temporary ability to suppress a tic is somewhat like waiting to scratch an itch or holding back a sneeze. The ability to suppress tics vary within and between individuals. Also, children are generally less able to suppress tics. Suppression of tics utilizes energy and increases stress and mental exhaustion and leaves the individual with less mental resources for attention and focus. Often the suppression of tics leads to an increase in tics once the person becomes exhausted from suppressing them. After school, after work or after being in a public place an individual may have a marked increase in tic intensity and frequency.
Tourette Syndrome is a chronic, life long disorder, however the severity of symptoms generally follows a favourable course. Typically, tics improve in severity and intensity as the individual matures and may end up having minimal to mild impact once they reach adulthood. Again, symptoms of Tourette Syndrome in adulthood range from mild to severe but generally tics will diminish throughout adolescence and into adulthood. As an adult, co-morbid conditions such as Attention Deficit Hyperactivity Disorder (ADHD) and Obsessive Compulsive Disorder (OCD) continue to cause more functional impairment to the individual than tics.
Coprolalia is the spontaneous utterance of socially objectionable or taboo words or phrases and is the most publicized symptom of Tourette Syndrome. It is not a symptom that is required for a diagnosis and only about 10% of Tourette’s patients exhibit this symptom.
Copropraxia is the spontaneous use of gestures that are socially objectionable or taboo.
Echolalia is a complex vocal tic involving the repetition of the words, phrases or sounds of others.
Palilalia is a complex vocal tic involving the repetition of the words, phrases or sounds of oneself.