Decoding and Reasoning Mental States in Major Depression and Social Anxiety Disorder

Abstract Background: Major depression (MDD) and social anxiety (SAD) disorders are debilitating psychiatric conditions characterized by disturbed interpersonal relationships. Despite these impairments in social interaction, little research has simultaneously evaluated the dysfunction in two aspects of theory of mind (ToM) in these disorders: Affective ToM or decoding mental states and cognitive ToM or reasoning mental states. Taking this into consideration, the current study attempts to compare both decoding and reasoning abilities in MDD, SAD, and healthy controls (HC). Methods: Subjects were 37 patients with MDD, 35 patients with SAD, and 35 HCs. ToM was measured with the Reading the Mind in the Eyes Test (RMET) and the Faux Pas Task, which assessed decoding skills and reasoning mental states, respectively. Results: Results showed that in decoding mental states, both the SAD and MDD groups achieved lower scores than HC group; moreover, there was no significant difference between SAD and MDD groups in decoding mental states. However, in reasoning mental states, SAD and HC groups had higher scores than the MDD group and no differences observed between SAD and HC groups in reasoning ability. Conclusions: Results of this study are discussed on generalized impairment in ToM or dysfunction in both decoding and reasoning mental states in MDD and only reasoning dysfunction in SAD.