Elicited imitation in children and adults with autism: the effect of different types of actions

Background It was proposed by Rogers & Pennington (1991) that an early deficit in imitation, together with a cascade of developmental disorders in emotion sharing and Theory of Mind, could be important in understanding autism. Having already found that imitation appeared not to be specifically or universally impaired in autism, the present study tested whether there were distinctions between different types of actions, such as symbolic versus non-symbolic, one-handed versus two-handed or symmetrical versus asymmetrical actions, on a test of elicited imitation. Methods A large battery of tasks was used to elicit imitation from three groups of autistic children and adults (aged 4-34 years of age), two groups of typically developing children and a group of children with mild-to-moderate intellectual disabilities. Results The majority of children and adults with autism had few impairments relative to the controls, although certain actions did seem more difficult, especially for the youngest children. For example, actions within the categories of 'symbolic actions' and 'asymmetrical actions' seemed to give some groups more problems. Certain types of errors such as hand reversals and using body parts as objects were found in both autistic and non-autistic groups, but, for the most part, in the youngest children in the whole sample. A final analysis compared the number of partial imitations for eight specific actions. Conclusions The overall picture was not one of an autism-specific deficit in imitation, but rather of a normal (i.e. age-related) developmental trend. These results are discussed in terms of Rogers & Pennington's theory and other leading theories.