Abstract
Impaired cooperation has been proposed to contribute to social dysfunctioning in borderline personality disorder (BPD). However, prior research has not distinguished active from reactive cooperation (i.e., nonexploitation versus non-retaliation)—two aspects of cooperative behavior associated with different basic personality traits (viz. Honesty-Humility and Agreeableness). The authors hypothesized that, due to low levels of Agreeableness, but normal levels of Honesty-Humility, borderline personality (BP) features are related to impaired reactive cooperation, but unrelated to active cooperation. Participants (N = 559) hypothetically played both the allocator in the dictator game and the recipient in the ultimatum game. High levels of BP features predicted impaired reactive cooperation in the ultimatum game, which was mediated through low Agreeableness. In contrast, BP features did not predict active cooperation in the dictator game—mirroring the nonassociation between BP features and Honesty-Humility. The findings highlight the importance of focusing on aspects of forgiveness in interventions aiming to improve cooperativeness in BPD.
