Impaired eye expression recognition in schizophrenia

Schizophrenia has been associated with abnormalities in recognising social emotions, inferring others' mental states and in gaze and visual scanning behaviours. Eye expression is known to convey considerable information in normal circumstances. Our study assessed the ability of individuals with schizophrenia to recognise simple and complex mental states from eye expressions alone. Sixteen individuals with a DSM-IV diagnosis of schizophrenia following SCAN [Schedules for Clinical Assessment in Neuropsychiatry (Wing JK, Babor T, Brugha T, Burke J, Cooper JE, Giel R et al. SCAN: schedules for clinical assessment in neuropsychiatry. Archives of General Psychiatry 1990;47:589-593).] interview and 16 healthy controls acted as participants. Expressions of 10 emotions (e.g. happy, afraid) and 10 complex mental states (e.g. thoughtful, bored), in the form of pictures of whole faces or eyes alone, were presented for recognition using a forced-choice response design. We observed impaired recognition of complex mental states in individuals with schizophrenia, from eye expressions alone (P=0.012). No differences in the recognition of basic emotions were detected. We also observed a negative correlation between illness chronicity and expression recognition performance (r=-0.65, P=0.006). The reduced ability of schizophrenia patients to recognise eye expressions of complex mental states could be interpreted as supporting a lack of "theory of mind". However, more parsimonious explanations based on impairments in basic recognition processes could also apply. An awareness of these processing abnormalities may have implications for future therapeutic strategies and our understanding of the pathophysiology of the disorder