Tics, or habit spasms, are frequent in childhood. They are sudden brisk involuntary contractions of muscles around the eyes or lower part of the face, and may spread to cause jerking of the neck, trunk and limbs. They are repetitive, non-purposeful, unilateral or bilateral and resemble the normal motor accompaniments of the startle reaction to a sudden, loud noise.
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.