Tics

Nervous tics are involuntary, brief, rapid, repetitive, arrhythmic movements or sounds that lack a purpose. They are of primary and benign nature and represent the most common movement disorder in pediatric age, affecting one in five children during childhood. They are usually transient, although their duration is variable: they can last weeks or extend for years, with more exacerbated periods and others more calm.

Depending on the affected area and complexity, the types of tics are:

• Motor tics: affect the muscles.
• Simple motor tics: affect a single muscle group, often in the face, and are brief and sudden. Common characteristics include grimacing, eyebrow raising, blinking, winking, or shoulder shrugging. This is the most common type of tic.
• Clonic tics: brief, rapid, and sudden muscle contractions.
• Dystonic tics: sustained, slow, twisting, or postural contractions.
• Tonic or tension tics: sustained and prolonged muscle contractions.
• Tremor tics: oscillatory movements in the hands, resembling tremors.
• Complex motor tics: involve more than one muscle group. They are coordinated and sequential movements, such as contorting, bending, jumping, touching objects, retracing steps, or touching oneself.
• Vocal or phonatory tics: involve the laryngopharyngeal muscles and produce sounds.
• Simple vocal tics: meaningless noises or sounds, such as coughing, throat clearing, howling, blowing, or snapping.
• Complex vocal tics: complex, differentiated, and meaningful expressions, such as repeating phrases or shouting insults.

In terms of their duration, tics are classified as:

• Transient: lasting less than one year.
• Chronic: lasting more than twelve months.

Symptoms

Generally, nervous tics are preceded by uncomfortable sensations that lead to the irresistible need to perform the movement or sound:

• Itching.
• Tingling.
• Pressure.
• Heat, burning.
• Increasing anxiety.

Causes

The exact cause of tics is unknown, although the most widely accepted theory associates them with a failure in the proper development of brain pathways that inhibit the fronto-subcortical circuits (from the motor cortex to the basal ganglia), responsible for controlling and modulating voluntary movements. Additionally, this dysfunction is thought to have a genetic basis.

Risk Factors

The likelihood of developing some form of tic increases under the following conditions:

• Age: they typically appear between 5 and 10 years old.
• Sex: more common in boys.
• Family history.
• They worsen transiently in situations of stress, anxiety, fatigue, boredom, impatience, or frustration.

Complications

Occasionally, tics are associated with other more complex disorders, such as learning difficulties, obsessive-compulsive behaviors, attention deficit and hyperactivity disorder (ADHD), or autism spectrum disorder (ASD). Tics may also be a symptom of Gilles de la Tourette syndrome, a chronic neurological condition characterized by the combination of at least two motor tics and one vocal tic, which is often associated with behavioral disorders such as impulsivity, hyperactivity, inattention, or sleep problems.

Moreover, tics can have negative consequences on the child’s social and academic life, as they may stigmatize them and make them the target of mockery, bullying, or social isolation, affecting their mental health and academic performance.

Prevention

To reduce the recurrence of tics, parents or guardians can follow these recommendations:

• Normalize the tics and not pay attention to them.
• Do not scold or punish the child for doing them.
• Ensure they get enough sleep.
• Avoid stress situations.
• Engage in relaxing activities that require concentration, such as reading or drawing.

Which doctor treats tics?

Childhood tics are treated in the pediatric neurology unit.