developmental disorders, the behaviors are typically less responsive to such efforts. In
other cases, the individual demonstrates self-restraining beha viors (e.g., sitting on hands,
wrapping arms in clothing, finding a protective device).
The repertoire of behaviors is variable; each individual presents with his or her own in-
dividually patterned, “signat ure” behavior. Examples of no n-self-injurious stereotypic
movements include, but are not limited to, bo dy rocking, bilateral flapping or rotating
hand movements, flicking or fl uttering fingers in front of the face, arm waving or flapping,
and head nodding. Stereotyped self-injurious behaviors include,  but are not limited to, re-
petitive head banging, face slapping, eye poki ng, and biting of hands, lips, or other body
parts. Eye poking is particularly concerning; it occurs more freq uently among children
with visual impairment. Multiple movements may be combined (e.g., cocking the head,
rocking the torso, waving a small string  repetitively in front of the face).
Stereotypic movements may oc cur many times during a da y, lasting a few seconds to
several minutes or longer. Frequency can vary  from many occurrences in a single day to
several weeks elapsing between episodes. The behaviors vary in context, occurring when
the individual is engrossed in other activities , when excited, stressed, fatigued, or bored.
Criterion A requires that the movements be  “apparently” purposeless. However, some
functions may be served by the movements. For example, stereotypic movements might
reduce anxiety in response to external stressors.
Criterion B states that the stereotypic mo vements interfere with social, academic, or