Tic
It can appear as a very fast movement (clonic) or with prolonged duration (dystonic). It is usually preceded by the need to move the affected part of the body and can be voluntarily restrained. Tics get worse in stressful situations, decrease during voluntary activity and disappear while sleeping. A simple motoric tic is a purposeless movement of a relaxed muscle group (for example: eye blinking, shoulder lifting, neck twitching, etc.). Complex motoric tics appear as partially purposeful movements (touching oneself and others, imitating the movements of others, hitting the wall, etc.). Vocal tics are identical to motoric tics and they are characterized by repetitive stereotypical vocalizations.
Tics can be primary and secondary. Primary tics include transient and chronic motoric or vocal tics, adult-onset tics (over 21 years of age), new-onset tics, recurrent childhood tics or as part of Gilles de la Tourette syndrome. Secondary tics can occur as part of a number of neurodegenerative diseases, after a stroke, head trauma, chromosomal disorders, developmental disorders, the influence of drugs, the effects of toxins (carbon monoxide) and infections (post-infectious encephalitis, Lyme disease, HIV infection, neurosyphilis, PANDAS).