Older individuals may struggle to understand what behavior is considered appropriate in
one situation but not another (e.g., casual beha vior during a job interview), or the different
ways that language may be used to communic ate (e.g., irony, white lies). There may be an
apparent preference for solitary activities or  for interacting with much younger or older
people. Frequently, there is a de sire to establish friendships wi thout a complete or realistic
idea of what friendship entails (e.g., one-sid ed friendships or friendships based solely on
shared special interests). Relationships with siblings, co-workers, and caregivers are also
important to consider (i n terms of reciprocity).
Autism spectrum disorder is also defined by restricted, repetitive patterns of behavior,
interests, or activities (as specified in Criterion B), which show a range of manifestations
according to age and ability, intervention, and current supports. Stereotyped or repetitive
behaviors include simple motor stereotypies (e.g., hand flappi ng, finger flicking), repeti-
tive use of objects (e.g., spinning coins, linin g up toys), and repetitive speech (e.g., echola-
lia, the delayed or immediate parroting of heard words; use of “you” when referring to
self; stereotyped use of words, phrases, or pr osodic patterns). Exce ssive adherence to rou-
tines and restricted patterns of behavior may be manifest in resistance to change (e.g., dis-
tress at apparently small changes, such as in packaging of a favorite food; insistence on
adherence to rules; rigidity of thinking) or ri tualized patterns of ve rbal or nonverbal be-
havior (e.g., repetitive questioning, pacing a perimeter). Highly restricted, fixated interests