Facial expression in patients with bipolar disorder and schizophrenia in response to emotional stimuli: a partially shared cognitive and social deficit of the two disorders.

Introduction: It has recently been highlighted that patients affected by schizophrenia (SCZ) and those affected by bipolar disorder (BD) undergo gradual chronic worsening of cognitive and social functioning. The objective of the current study was to evaluate and compare (using the Facial Action Coding System [FACS]) the way by which patients with the two disorders experience and display emotions in relation to specific emotional stimuli. Materials and methods: Forty-five individuals participated in the study: 15 SCZ patients, 15 BD patients, and 15 healthy controls. All participants watched emotion-eliciting video clips while their facial activity was videotaped. The congruent/incongruent feeling of emotions and the facial expression in reaction to emotions were evaluated. Results: SCZ and BD patients presented similar incongruent emotive feelings and facial expressions (significantly worse than healthy participants); SCZ patients expressed the emotion of disgust significantly less appropriately than BD patients. Discussion: BD and SCZ patients seem to present a similar relevant impairment in both experiencing and displaying emotions; this impairment may be seen as a behavioral indicator of the deficit of social cognition present in both the disorders. As the disgust emotion is mainly elaborated in the insular cortex, the incongruent expression of disgust of SCZ patients can be interpreted as a further evidence of a functional deficit of the insular cortex in this disease. Specific remediation training could be used to improve emotion and social cognition in SCZ and BD patients.