What Is It?
A tic is a sudden, rapid, repetitive movement (motor tic) or vocalization (vocal tic).
There are two main types of tics:
Simple tics involve one muscle group
Simple motor tics include head shaking, eye blinking, sniffing, neck jerking, shoulder shrugging and grimacing. These are more common.
Simple vocal tics include coughing, throat clearing and barking.
Complex tics involve more than one muscle group
Complex motor tics include self-hitting or self-biting, jumping and hopping, and twirling while walking.
Complex vocal tics include repeating words out of context, echoing what someone else said and speaking obscenities.
Tics sometimes change over time from one simple type of tic to another or from a simple to a complex tic. Some tics are slow and sustained rather than brief and rapid. Some involve the lower body.