Facial emotion space in schizophrenia

Abstract

Introduction. Previous studies show that patients with schizophrenia have a deficit in facial emotion recognition. In the framework of emotion categorisation theories, the purpose of the present study was to test if this impairment could result from abnormal boundaries between emotions (whether these boundaries are shifted along continuums or are less sharpened).

Method. Twenty-six schizophrenic patients and the same number of healthy participants were required to perform a facial emotion recognition task and an emotion categorisation task with different emotion intensities obtained using morphing techniques.

Results. The main results indicate that schizophrenic patients exhibited an emotion space with less sharpened categories which favoured confusion between different emotions and intrusions of other emotions. Moreover, correlations between different indices showed that the less sharpened the categories, the more frequent the intrusions and the less discriminable the facial emotions.

Conclusion. We conclude that patients with schizophrenia process facial expressions in a less categorical way which involves impaired recognition of facial expressions. Such a specific impairment may favour false perceptions and lead to the settlement of delusional ideas.

Acknowledgements

All participants gave their informed consent to participate in the study, which was performed in accordance with the ethical standards laid down in the 1964 declaration of Helsinki. We gratefully acknowledge Professor Jean-Louis Terra and clinical staff managed by Mrs Ghislaine Bailly for their collaboration and use of facilities. We wish to thank Gethin Hughes and Karen Reilly for their assistance in proofreading this paper. This work was supported by an ACI “Jeunes Chercheuses et Jeunes Chercheurs 2003” grant (No. 6056) from the French Ministry of Research to J-YB.