Tic

Tic is a sudden, repetitive, nonrhythmic motor movement or vocalization involving discrete muscle groups. Tics can be invisible to the observer, such as abdominal tensing or toe crunching. Common motor and phonic tics are, respectively, eye blinking and throat clearing.

Habit-tic deformity example on thumb

Classification

Tics are classified into several types:

• Simple tics: These are sudden, brief, repetitive tics that involve a limited number of muscle groups.
• Complex tics: These are distinct, coordinated patterns of movements involving several muscle groups.

Causes

Tics are believed to result from dysfunction in cortical and subcortical regions, the thalamus, basal ganglia and frontal cortex. Stress and sleep deprivation can worsen tics; alcohol, cigarettes, and caffeine can also exacerbate tics in some people.

Treatment

Treatment is not always necessary if the tics are not severe. If tics are severe or interfere with daily life, then medication and therapeutic interventions may be necessary.

See also

• Tourette syndrome
• Habit reversal training
• Comprehensive Behavioral Intervention for Tics