LAUSR

Abstract Objectives: Social cognitive deficits have been discussed to be endophenotypes for schizophrenia and other serious mental illnesses. The current study aimed to assess emotional intelligence (EI) in unaffected siblings of schizophrenia patients to investigate its potential role as endophenotype for schizophrenia. Methods: EI was measured in 56 schizophrenia patients, 57 unaffected siblings, and 127 healthy control subjects by using the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT). In addition, non-social cognition was assessed with the Brief Assessment of Cognition in Schizophrenia (BACS). Linear mixed models with compound symmetric correlation structure were used for of the three groups with respect to EI and non-social cognition. Results: Schizophrenia patients showed significantly lower overall EI and performed significantly worse in three out of four MSCEIT branches compared to unaffected siblings and control subjects, whereas the two latter groups had comparable EI levels. Similar performance patterns (patients