Theory of mind abilities of children with schizophrenia, children with autism, and normally developing children.

Theory of mind (ToM) abilities of children with schizophrenia, children with high functioning autism, and normally developing children, matched on mental age (MA), verbal MA, and performance MA, were compared. Both clinical groups were matched on chronological age as well, whereas the normally developing children were younger. A fact belief task, a value belief task, a deception task, and a false belief task were administered. The three groups did not differ on the fact belief task. Children with autism performed more poorly than normally developing children on value belief and false belief tasks, and more poorly than individuals with schizophrenia on the deception task. Children with schizophrenia performed more poorly than normally developing children only on the false belief task. Overall, the group with autism passed significantly fewer tasks compared to the normally developing group. ToM abilities correlated with verbal abilities for individuals with autism. The ToM abilities of children with paranoid schizophrenia and children with undifferentiated or disorganized schizophrenia did not differ. Findings strengthen the notion of a limited understanding of ToM in schizophrenia, and support the notion that ToM deficits, although more severe in autism, are not unique to autism.