Cognitive mechanisms of alexithymia in schizophrenia: Investigating the role of basic neurocognitive functioning and cognitive biases

摘要

Alexithymia is an important but poorly understood emotional deficit in schizophrenia. We aimed at investigating the role of basic cognitive functions, cognitive biases, and symptom severity in alexithymia among patients with schizophrenia. Sixty patients (31 females) with schizophrenia were assessed with standardized clinical interviews for symptom severity. Cognitive functioning was assessed with neuropsychological tests. A self-report scale (Davos Assessment of Cognitive Biases, DACOBS), as well as two experimental tasks assessing jumping to conclusions (the Fish task) and source monitoring (Action memory task), were used to investigate cognitive biases. Alexithymia was assessed with the Toronto Alexithymia Scale (TAS-20). Alexithymia was related to the severity of hallucinations but not delusions. Patients with a lifetime history of more psychotic symptoms had higher alexithymia. Alexithymia has broad relationships with different cognitive biases, especially in the self-reported measure. These relationships were not affected by neurocognition and symtpoms severity. In particular, difficulties in identification of feelings were related to various cognitive biases. Dysfunctional information processing can thus be considered as potential psychological correlates of alexithymia. The theoretical and clinical implications of our findings are discussed.