Several studies have consistently shown that patients with schizophrenia spectrum disorders (SSD) display less expressive behaviours during social interaction. There is, however, a paucity of research into the underlying emotional or cognitive abnormalities in SSD. It is theoretically conceivable that patients engage less in social interaction, because they misinterpret intentions and dispositions or overattribute desires and thoughts to their interlocutors.

We tested the hypothesis that the non-verbal behaviour of patients with SSD correlates with their understanding of other people's thoughts and intentions, known as “theory of mind” (ToM) and with their ability to decipher emotional expressions from faces. Standard ToM picture stories and pictures of facial affect were given to a group of 50 patients with SSD. The patients’ nonverbal behaviour was measured using the Ethological Coding System for Interviews (ECSI; Troisi, 1999). In addition, intelligence, executive functioning and psychopathology using the PANSS were assessed.

Preliminary results suggest that patients’ nonverbal behaviour correlates with ToM, emotion recognition, verbal intelligence and cognitive flexibility.

These findings point to an important link of social cognitive abilities with the actual non-verbal behaviour of patients with schizophrenia.