Neuropsychological impairment: the disturbed effect of self-processing in patients with major depressive disorder

Abstract

Neuropsychological impairment has long been established as a fundamental characteristic of depression, but a generally accepted, specific pattern of neuropsychological impairment has not been summarized. In this study, we examined the classic neuropsychological paradigm of self-face recognition, to explore whether the self was impaired in major depressive disorder (MDD). Eighteen MDD patients and 20 healthy subjects were recruited to participate in this study. By using a face morphing technique, we measured the size of processing bias in MDD patients during different face discrimination tasks relative to controls. Results of analysis of variance (ANOVA) showed a significant main effect of Group (F(1, 36) = 7.388, P = 0.01). Subsequent independent t-tests further revealed that self bias (t = 2.636, P = 0.012) and self-recognition bias (t = 2.190, P = 0.035) observed in self-famous task and self-stranger task respectively for patients were significantly greater than that for controls. Both self-processing and self-recognition were impaired in patients with MDD, indicating that MDD individuals might exist level of self-abnormalities. These findings provide a new perspective for further study on the etiological and pathological mechanisms of MDD.