Emotional Intelligence deficits in schizophrenia: The impact of non-social cognition.

Background: Previous studies using the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) revealed significant performance deficits across all areas of Emotional Intelligence (EI) in schizophrenia patients compared to healthy controls. However, none of these studies has investigated a potential influence of non-social cognition on these findings.

Methods: 56 schizophrenia outpatients and 84 control subjects were investigated using the MSCEIT and the Brief Assessment of Cognition in Schizophrenia (BACS). Analyses of covariance were performed with adjustment for the BACS composite score and education. To investigate this issue in more detail, a mediation analysis was conducted.

Results: Patients showed significantly lower EI and non-social cognition levels compared to healthy controls. After adjustment for BACS composite score and education, only the group difference in the "managing emotions" branch and thus in the "strategic" EI part of the MSCEIT remained statistically significant, whereas for all other MSCEIT branches (perceiving, using, understanding emotions) statistical significance was lost. The mediation analysis revealed that the difference between schizophrenia patients and controls regarding the MSCEIT total score was almost fully attributable to the mediating effect of non-social cognition.

Conclusions: Our findings suggest that in schizophrenia patients EI is largely influenced by non-social cognitive functioning. Only the "managing emotions" branch was found to be independent of non-social cognition. Consequently, non-social cognitive performance was mainly responsible for the observed differences in EI between schizophrenia patients and controls. This has to be taken into account when interpreting MSCEIT data in this population.