This study sought to differentiate pervasive developmental disorder not otherwise specified (PDDNOS) from similar nonautistic disorders on the basis of a cognitive deficit, theory of mind (ToM), which is the ability to infer mental states in others, a deficit highly prevalent in autism, a disorder similar to PDDNOS. Results suggest that children…

Describes two experiments that examined children's understanding of the distinction between real and apparent emotion. Discusses the findings in relation to research concerning children's concept of mind, their grasp of the appearance-reality distinction; their ability to produce complex, embedded justifications; and their ideas about emotion.…