Theory of mind in borderline and cluster-C personality disorder

Borderline Personality Disorder (BPD) is associated with interpersonal problems, such as intense, unstable relationships and fears of abandonment. It has been hypothesized that deficits in social cognitive capacities explain these difficulties. One important aspect of social cognition is theory of mind (ToM)-the capacity to infer others' mental state. We tested ToM capacities with Happé's advanced ToM-test in 16 BPD patients, 16 Cluster-C PD patient controls, and 28 nonpatients. Social reasoning (WAIS Picture Arrangement), general intelligence, and current mood were also assessed. With and without controlling for intelligence, social reasoning, and mood, no evidence for deficits in ToM in BPD patients was found. In fact, both Cluster B and Cluster C patient groups tended to show generally superior performance to the nonpatients on the subscales of Happé ToM-test. All tests correlated similarly with intelligence in the 3 groups. These findings do not support the hypothesis that BPD patients have inferior theory of mind capacities.