Objective: Clozapine and risperidone are used for treatment-resistant schizophrenia and known to improve the positive and negative symptoms. However, there are some conflicts about effects on social cognition, which is measured with facial emotion recognition ability. The impairments in facial emotion recognition ability have frequently been in different stages of the illness and might have negative influences on psychosocial functioning. In the present study, we aimed to examine clozapine and risperidone effects recognizing facial emotions in patient with treatment-resistant schizophrenia.
Methods: Thirty-four patients were screened for the study, and 19 patients were included. All patients were evaluated with Positive and Negative Syndrome Scale (PANSS), Calgary Depression Scale for Schizophrenia, and Functional Remission of General Schizophrenia Scale at baseline and after 16–20 weeks of clozapine (n = 12) or risperidone (n = 7) treatment. Furthermore, the Facial Emotion Recognition Test was performed before and after treatment. The test included the photos of four male and four female models (totally 56 mixed photos) with happy, surprised, fearful, sad, angry, disgusted, and neutral facial expressions from Ekman and Friesen’s catalog.
Results: The mean dose of the index drug in clozapine group was 295.83 ± 103.26 mg/day. The mean positive (p = .002), negative (p = .050) general psychopathology (p = .002), and total score (p = .002) according to the PANSS were significantly improved after treatment. The mean dose of the index drug in risperidone group was 6.86 ± 1.57 mg/day. The mean positive symptom (p = .018) and total score (p = .041) were significantly improved after treatment but negative symptom scale (p = .396) and general psychopathology (p = .149) scores did not change. There were no significant differences between baseline and after treatment in clozapine and risperidone group according to the accuracy rate of facial emotion recognition expressions (p > .05 for each). At baseline phase, the patients were significantly impaired in recognizing disgusted faces in risperidone than those in clozapine group (p = .032) and it was significantly poorer after treatment with risperidone than with clozapine (p = .031). The patients responded significantly faster after the treatment to all facial emotions except for fearful faces (p = .355).
Conclusions: Clozapine and risperidone were not found to have extensive effects on the ability to recognize facial emotions because of ineffectiveness to negative symptoms as in our study. We speculated that the higher dopaminergic receptor occupancy rate of risperidone in insular cortex than that of clozapine might be related with hypo-activation of insula that was associated with particular deficit in ability to recognize expressions of disgust in patients with schizophrenia. Impaired facial emotion recognition ability is present even in first-episode psychosis, which might be a trait marker in schizophrenia.