Tics- Simple and Complex

A tic is a brief, repetitive, purposeless, nonrhythmic, involuntary movement or sound. Tics that produce movement are called “motor tics,” while tics that produce sound are called “vocal tics” or “phonic tics.” Motor tics seems to be more common than vocal tics.

Tics are often characterized by whether they are “simple” or “complex.” A simple tic involves one muscle group or one simple sound. Many simple motor tics are associated with the face/head/neck region, such as eye blinking, head jerking, shoulder shrugging, mouth grimacing, etc. Simple vocal tics include throat-clearing sounds, grunting, sniffing, and coughing. Simple motor tics of the face and head/neck region are the most common first tics in children.

A complex tic involves a coordinated movement produced by a number of muscle groups (complex motor tic) or a linguistically meaningful utterance or phrase (complex vocal tic). As examples, complex motor tics can involve touching objects or other people, jumping up and down, spinning around, or even more complex motor sequences such as imitating someone else’s actions (echopraxia) or exhibiting inappropriate or taboo gestures or behaviors (copropraxia). Complex vocal tics may involve having to repeat one phrase over and over, whether it is something one heard (echolalia) or one’s own last words (palilalia).