title: Inconsistency and social decision making in patients with Borderline Personality Disorder.
abstract: Inconsistent social behavior is a core psychopathological feature of borderline personality disorder. The goal of the present study was to examine inconsistency in social decision-making using simple economic social experiments. We investigated the decisions of 17 female patients with BPD, 24 patients with major depressive disorder (MDD), and 36 healthy controls in three single shot economic experiments measuring trust, cooperation, and punishment. BPD severity was assessed using the Zanarini Rating Scale for BPD. Investments across identical one-shot trust and punishment games were significantly more inconsistent in BPD patients than in controls. Such inconsistencies were only found in the social risk conditions of the trust and punishment conditions but not in the non-social control conditions. MDD patients did not show such inconsistencies. Furthermore, social support was negatively correlated with inconsistent decision-making in the trust and punishment game, which underscores the clinical relevance of this finding.
authors.affiliation: Institute of Psychology, University of Bern, 3000 Bern 60, Switzerland; Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden.
authors.forename: Nora
authors.initials: N
authors.lastname: Preuss
authors.affiliation: Psychiatric University Hospital, University of Bern, 3000 Bern 60, Switzerland.
authors.forename: Laura S
authors.initials: LS
authors.lastname: Brändle
authors.affiliation: Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich, 8006 Zürich, Switzerland.
authors.forename: Oliver M
authors.initials: OM
authors.lastname: Hager
authors.affiliation: Psychiatric University Hospital, University of Bern, 3000 Bern 60, Switzerland.
authors.forename: Melanie
authors.initials: M
authors.lastname: Haynes
authors.affiliation: Department of Economics, University of Konstanz, 78457 Konstanz, Germany; Thurgau Institute of Economics, 8280 Kreuzlingen, Switzerland.
authors.forename: Urs
authors.initials: U
authors.lastname: Fischbacher
authors.affiliation: Psychiatric University Hospital, University of Bern, 3000 Bern 60, Switzerland. Electronic address: gregor.hasler@puk.unibe.ch.
authors.forename: Gregor
authors.initials: G
authors.lastname: Hasler
mesh_terms: D000328:Adult; D001883:Borderline Personality Disorder / Q000523:psychology*; D003657:Decision Making / Q000502:physiology*; D003865:Major Depressive Disorder / Q000523:psychology; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D008875:Middle Aged; D011678:Punishment; D012919:Social Behavior; D012944:Social Support; D035502:Trust; D055815:Young Adult
keywords: Behavioral economics; Borderline personality disorder; Game theory; Interpersonal behavior; Intra-individual variability