Abstract

Disturbed interpersonal relationships and misreading of others' intentions are core symptoms of borderline personality disorder (BPD). Despite these impairments, some studies have found an enhanced theory of mind (ToM) in BPD patients. Taking this into consideration, the current study attempts to further understand these discrepancies by separating ToM into two domains: affective and cognitive. Moreover, the study considered the role of comorbid symptoms of depression in these patients. Subjects were 21 patients with BPD, 23 patients with BPD and comorbid major depressive disorder (MDD), and 25 healthy controls (HC). ToM was measured with the Reading the Mind in the Eyes Test (RMET) and the Faux Pas Task, which assessed the affective and cognitive aspects of ToM, respectively. In addition, all participants were evaluated with the Beck Depression Inventory (BDI). Results showed that in both BPD groups (i.e., BPD without MDD and BPD with MDD) affective ToM scores were higher than in the HC group; however, in the cognitive ToM, the HC group performed better than the both BPD groups. Also, overall the BPD group with MDD had decreased ToM skills. Finally, BPD groups received greater scores on the BDI as compared to the HC group.