Theory of mind in adolescents with early-onset schizophrenia: correlations with clinical assessment and executive functions.

Objective: We examined Theory of Mind (ToM) abilities in adolescents with early-onset schizophrenia (EOS) and their correlation with clinical findings and Executive Functions (EF).
Methods: The ToM abilities of 12 adolescents with EOS were compared with those of healthy participants matched in age and educational level. The Moving Shapes Paradigm was used to explore ToM abilities in three modalities: random movement, goal-directed movement and ToM - scored on the dimensions of intentionality, appropriateness and length of each answer. EF was tested using Davidson's Battery and the clinical psychopathology with the Positive and Negative Syndrome Scale (PANSS).
Results: Adolescents with EOS were significantly more impaired than controls in the three dimensions evaluated for the goal-directed and ToM modalities. Regarding the random movement modality, the only difference was in appropriateness (p<0.01). No correlation with age or level of education was evident for ToM skills. Total PANSS score was negatively correlated with appropriateness score for the goal-directed (p=0.02) and ToM modalities (p=0.01). No correlation existed between performance in the ToM Animated Tasks and positive, negative or disorganisation PANSS subscores. No correlations were found among the three scores in the Moving Shapes Paradigm and any measures of the accuracy of the three tasks assessing EF.
Conclusion: Our results confirm previous findings of ToM deficits in adult individuals with schizophrenia and attest the severity of these deficits in patients with EOS.