Table 1.

Different types of stereotypic behaviors

Type	Definition
Face	Grimacing, lips or tongue movements, opening the mouth, mouth stretching, licking[17], smoking, puffing noise[18], sucking objects[16].
Head and neck	Head tilting, shaking, nodding, hair twirling, head banging, neck stretching[19], teeth grinding[20], hair pulling[20], tongue wagging, biting bottoms[18], neck extension.
Trunk	Body rocking, spin[12], spinning or rotation of entire body[17].
Shoulders	Bending, scrunching;arching the back;shrugging the shoulders.
Arm/leg	Arm flapping, bilateral repetitive movements involving the arms and hands such as crossing the arms on the chest, stamping the feet, tapping one's feet, heel and toe walking[17].
Hand/finger	Hand flapping, slapping, nail biting[21], finger wiggling, Shaking, tapping, waving, clapping, opening-closing, rotating or twirling the hand or fingers, thumb-sucking, pointing, fanning fingers[17], fluttering fingers in front of the face, picking skin, scratch self, arrange objects[16].
Hand/finger with object	Shaking, tapping, banging, twirling an object, tapping pencils, touching, rubbing, repetitive ordering[22], arrange toys in patterns[12], adding objects to a line[17], manipulating of objects[16].
Gait	Pacing, jumping, running, skipping, spinning.
Self-directed	Covering the ears, mouthing, smelling, rubbing the eyes, tapping the chin, slapping self or an object or surface, touching genitals, self-mutilating behavior[22].
Visual	Atypical visual explanatory behaviors[23] such as staring at an object or the fingers ‘out of the corner of the eyes, eyelid closure, squinting eyes[17].
Vocal and speech	Vocalization, humming, tongue clucking, echolalic words/phrases[24], telling or asking[22].