Impact of intelligence on social cognition in mentally disordered offenders: preliminary evidence in schizophrenia and personality disorders

Social cognition (SC) enables individuals to perceive, interpret, and respond to the intentions and behaviours of others. Impairments in SC are common among forensic psychiatry patients and can contribute to the emergence of violent behaviour, and such impairment may differ according to a patient’s intelligence quotient (IQ) and psychiatric diagnosis (schizophrenia spectrum vs. personality disorders). In a sample of 75 male forensic inpatients, we examined both emotional and cognitive social cognition. Cognitive SC impairment was present in 39.2% of patients and emotional SC impairment in 25.3%. Higher IQ emerged as a strong, independent protective factor for cognitive SC (an approximately ten-fold effect), regardless of psychiatric diagnosis or criminal history. For emotional SC, average intelligence and a personality-disorder diagnosis were protective relative to schizophrenia, while foreign nationality increased risk. Recidivism and crime severity were unrelated to SC deficits. These findings suggest that clinicians should account for a patient’s level of intelligence and assess emotional and cognitive SC separately when referring mentally disordered offenders for SC training to improve their prosocial skills.

Journal article