Do children with PDDNOS have a theory of mind?

This study sought to differentiate PDDNOS from a similar nonautistic disord er (i.e., language impairment) on the basis of a cognitive deficit, theory- of-mind (ToM). ToM is an ability to infer mental states in others and has b een found to be highly prevalent in autism, a disorder that shares many cha racteristics with PDDNOS (Baron-Cohen, 1985; Volkmar & Cohen, 1988). A samp le of 28 children with either PDDNOS or a language impairment formed two gr oups (n = 14), matched on gender and verbal mental age. Participants were a dministered the brain function task (Baron-Cohen, 1989) and the false belie f task (Perner, Frith, Leslie, & Leekam, 1989) to assess ToM. Results sugge st that children with PDDNOS are deficient in a ToM ability, however, this relationship is not as strong as in previous studies with autistic samples, suggesting that children with PDDNOS may have a greater ToM ability. The e xistence of PDDNOS on the higher end of a spectrum of the Pervasive Develop mental Disorders as well as the construct of ToM itself existing on a conti nuum are discussed.