Autistic children's use of semantic common sense and theory of mind: a comparison with typical and mentally retarded children.

To compare Japanese autistic children's use of semantic knowledge and theory of mind with mentally retarded and typically developing children's, they were tested on their comprehension of active and passive sentences and false belief understanding. Autistic children were sensitive to plausibility levels of semantic bias as were 4-year-olds with typical development when comprehending sentences, although impaired in belief understanding as compared with mentally retarded children and typically developing 5-year-olds. Children's sentence comprehension had no association with belief understanding. Results suggest that autistic children with certain verbal intelligence can utilize semantic common sense to comprehend sentences as can typically developing children and that the ability to comprehend sentences is relatively independent of theory of mind.