Dissociable aspects of imitation: a study in autism.

What does it mean for a child to imitate someone else? We tested matched groups of children with and without autism (n=16 for each group, with a mean chronological age of 11 years and a mean verbal mental age of 6 years) to investigate two potentially dissociable aspects of imitation: copying goal-directed actions, on the one hand, and imitating the "style" with which a person demonstrates those actions, on the other. Our hypothesis was that the latter, but not necessarily the former, kind of imitation reflects a special quality of interpersonal engagement in which one person identifies with another, and that the propensity to identify with others is specifically weak in autism. As predicted, participants with and without autism were similar in their ability to copy six relatively complex goal-directed actions but were significantly different in imitating the style with which six simpler goal-directed actions were executed, especially when style was incidental to accomplishing a goal. We interpret the findings in terms of a link among children's capacities for intersubjective engagement, imitation, and learning new ways to relate to objects.