Tics are involuntary movements or vocalizations, of a repetetive nature.
They are common in childhood - about one in thirty children will exhibit some sort of tic at some time during childhood. Tics may sometimes be the root cause of frustrating searches for the source of a nagging little cough in a child. The tic might seem to begin either for no appreciable reason, or perhaps be incited by something like an eye irritation which begins a cycle of blinking that doesn't stop when the irritation is gone. The simple tic usually goes away in six months or so, seemingly sooner if the child is not being reminded of it all the time by his family. Sometimes the symptoms become more chronic.