Are There Differences in Neurocognition and Social Cognition Among Adolescents with Schizophrenia, a Pervasive Developmental Disorder, and Both Disorders?

Schizophrenia (SCH) and pervasive developmental disorders (PDDs) belong to different diagnostic categories. There is, however, overlap between these 2 diagnostic groups. The aim of this preliminary study was to evaluate some aspects of neurocognitions and social cognitions in adolescents with SCH (n = 10, 2 boys and 8 girls; age range = 13.3-17.7 years), a PDD (n = 15, 7 boys and 8 girls; age range = 13.3-18.0 years), or both disorders (n = 8, 5 boys and 3 girls; age range = 13.5-18 years). Eight subtests (Information, Similarities, Arithmetic, Comprehension, Picture Completion, Coding B, Block Design, and Object Assembly) of the Wechsler Intelligence Scale for Children-Third Version and 2 subtests (Theory of Mind [ToM] and Affect Recognition) of the NEPSY-II were administered. Adolescents with both disorders and those with a PDD only performed better on visual processing tasks than did adolescents with SCH only. On the other hand, adolescents with both disorders as well as those with SCH only experienced more problems with processing speed than did adolescents with a PDD only. Adolescents with SCH only performed significantly more poorly with verbal ToM tasks compared with those with a PDD only. Adolescents with both disorders performed as well as those with SCH only. All in all, our preliminary findings support the current idea that SCH and PDDs are separate disorders.