Impaired complex theory of mind and low emotional self-awareness in outpatients with borderline personality disorder compared to healthy controls: A cross-sectional study

Abstract

Studies on the theory of mind (TOM) and alexithymia in borderline personality disorder (BPD) have yielded inconsistent results. Also, the relationship between TOM abilities and alexithymia facets as two domains of social cognition has not been studied in BPD. This study aimed to fill this gap. Participants were 50 outpatients with BPD and 50 age and gender-matched healthy controls. Assessments performed using Reading the Mind in Eyes Task (RMET), Toronto Alexithymia Scale (TAS-20), Faux Pas Task (FPT), and Digit Span subtest of Wechsler Adult Intelligence Scale. Results showed that BPD patients scored lower on overall FPT (p < .001) and its cognitive (p < .001) and affective TOM (p < .001) subtests but were comparable with healthy controls in emotion recognition ability assessed by RMET (p = .241). The BPD group also scored significantly lower in overall alexithymia (p < .001) and subscales of difficulty identifying feelings (DIF; p < .001) and difficulty describing emotions (DDF; p = .001). However, they performed similarly to the healthy control group in externally oriented thinking (EOT; p = .164). Correlation analysis revealed a significant negative correlation between EOT and RMET in the BPD group (r = -0.33, p < .05). No association, however, was found between FPT and RMET. This study suggests that BPD patients are impaired in the complex TOM abilities and have lower self-awareness of emotions, but their recognition of others' emotions is intact. Also, the results demonstrate that a heightened level of EOT is associated with difficulties in facial emotion recognition in BPD patients.

Keywords: Alexithymia; Borderline personality disorder; Emotion recognition; Social cognition; Theory of mind.