Chronic Motor Tic Disorder

Overview

Chronic motor tic disorder is a condition in which a person has one or more motor tics, which are sudden, repetitive, involuntary movements, that last for more than a year. Unlike Tourette syndrome, it involves only motor tics and not vocal tics. The condition usually begins in childhood.

Tics can range from simple movements such as eye blinking or shoulder shrugging to more complex sequences. They often wax and wane in frequency and severity, and many people can briefly suppress them with effort, though this usually builds an uncomfortable urge to release the tic. For many children the tics are mild and improve over time, and treatment is needed only when they interfere with daily life.

Symptoms

The main feature is one or more motor tics that have persisted for more than a year. These may include:

• Simple motor tics such as eye blinking, facial grimacing, head jerking, or shoulder shrugging
• More complex movements such as touching, jumping, or repeating a sequence of motions
• Tics that come and go, change over time, and vary in intensity
• An uncomfortable urge or sensation before the tic, relieved by performing it
• Temporary ability to hold back tics, often followed by a stronger release

By definition, vocal tics such as throat clearing, grunting, or making words are not part of chronic motor tic disorder; if both motor and vocal tics are present, the condition is classified differently.

Causes

The exact cause is not fully understood, but tic disorders are thought to involve differences in the brain circuits that control movement. Contributing factors include:

• Genetics: Tic disorders often run in families, suggesting an inherited tendency.
• Brain chemistry and circuits: Differences in the pathways involving the basal ganglia and chemical messengers such as dopamine are believed to play a role.
• Developmental factors: Tics usually emerge during childhood as the brain is developing.

Tics are not caused by bad behavior or poor parenting, and they are not deliberate. Stress, excitement, and tiredness can temporarily make tics more noticeable.

Risk Factors

• A family history of tics or Tourette syndrome
• Being male, as tic disorders are more common in boys
• Childhood onset, typically before age 18
• Coexisting conditions such as ADHD or obsessive-compulsive features

Diagnosis

There is no single test for chronic motor tic disorder; the diagnosis is based on the history and observation of the tics. A doctor will:

• Confirm that one or more motor tics have been present for more than a year
• Confirm the absence of vocal tics and that tics began before age 18
• Make sure the tics are not caused by another medical condition or a medication
• Look for related conditions such as ADHD, anxiety, or obsessive-compulsive symptoms

Tests may occasionally be used to rule out other movement disorders, but they are not needed to make the diagnosis itself.

Treatment

Many children with mild tics need only reassurance and education, since tics often improve with time. Treatment is considered when tics interfere with daily life, school, or self-esteem.

• Education and reassurance: Understanding that tics are involuntary and often temporary reduces worry for the child and family.
• Behavioral therapy: Comprehensive Behavioral Intervention for Tics (CBIT) teaches awareness of the urge and a competing response to reduce tics.
• Medication: When tics are severe or distressing, certain medications can lessen them, but they are used selectively because of possible side effects.
• Treating related conditions: Addressing coexisting ADHD, anxiety, or obsessive-compulsive symptoms often improves overall functioning.

Prevention

• Tics cannot be prevented, but their impact can be reduced
• Reduce stress and ensure enough sleep, since fatigue and stress can worsen tics
• Create a supportive environment at home and school that does not draw negative attention to tics
• Address related conditions such as anxiety or ADHD early

When to See a Doctor

See a doctor if a child has involuntary movements that persist for several weeks or longer, especially if they interfere with school, friendships, or self-esteem, or cause physical discomfort. Seek prompt evaluation if tics appear suddenly and severely, are accompanied by other new neurological symptoms, or follow a new medication, so that other causes can be ruled out.

Related Topics

Frequently Asked Questions

References

1. Centers for Disease Control and Prevention (CDC). Tourette Syndrome and Tic Disorders.
2. National Institute of Neurological Disorders and Stroke (NINDS). Tics.
3. MedlinePlus, U.S. National Library of Medicine. Tics.
4. American Academy of Neurology. Treatment of tics in Tourette syndrome and chronic tic disorders.