Tics are repetitive, stereotyped movements, such as lip smacking, throat clearing or grimacing. People can suppress tics for a while but eventually feel compelled to give in to the impulse, in order to relieve the tension that builds up when the tic is suppressed. Mild tics are common in all ages, though they're most common in children. Some conditions cause more complex tics, composed of a combination of different movements.
Transient Tic Disorder
Transient tic disorder, the most common form of tics, affects about 10 percent of children in the early years of elementary school, as noted by the American Academy of Child and Adolescent Psychiatry. Common tic patterns include shrugging the shoulders, sticking out the tongue and curling the toes. Anxiety, stress and fatigue may worsen tics. Simple tics usually disappear on their own within several months, though they can turn into a chronic tic disorder.
Tourette's Syndrome
People with Tourette's syndrome exhibit a variety of tics, including shouting obscenities. As the National Tourette's Syndrome Association explains, the condition starts before age 18 and lasts at least one year. The first symptom is often a facial tic, such as blinking or grimacing. Later on, movements of the body appear in addition to vocal tics. Tics in this disorder can be frequent and can interfere with functioning. The severity of Tourette's can vary widely. At times, it becomes a disabling condition. Most people who suffer from Tourette's can lead full and productive lives despite their tics. Children with Tourette's may have associated conditions such as ADHD or obsessive compulsive disorder.
Other Causes
Stimulant medications such as methylphenidate, used in the treatment ADHD, can cause tics. As explained by "Adams and Victor's Principles of Neurology," various conditions that affect the basal ganglia, the area of the brain responsible for involuntary movements, can also lead to tics. These conditions include head trauma, stroke and encephalitis, which is an infection of the brain.
References
- American Academy of Child and Adolescent Psychiatry: Tic Disorders
- National Library of Medicine: Transient Tic Disorders
- National Tourette's Syndrome Association: What Is Tourette's Syndrome
- "Adams and Victor's Principles of Neurology"; Maurice Victor and Allan Ropper; 2001
