Difficulties in the understanding of false belief: specific to autism and other pervasive developmental disorders?

The present study examined the performance on a false belief task of atypical autistic children, i.e., children with a pervasive developmental disorder not otherwise specified (n = 50), socially immature children (n = 50), and normal children (n = 50). Children were shown a chocolate box and its unexpected content, i.e., a pencil, and then required to indicate what a friend would say about the content of the box. Results can be summarized: (1) over-all, 3-year-old children performed less well than children of 6 years. (2) Responses of 3-year-old atypical autistic and socially immature children did not differ significantly from those of normal children of the same age. (3) At age 6, normal children performed better than atypical autistic and socially immature children. (4) In general, no differences in performance between atypical autistic and socially immature children were found, and (5) their performance was linked to intelligence. The results support prior findings that atypical autistic children find it difficult to understand false beliefs; however, this difficulty does not seem to be specific for (atypical) autism, but might be a common feature of social immaturity in general.