Contents lists available at ScienceDirect Psychiatry Research journal homepage: www.elsevier.com/locate/psychres The effects of social exclusion on response inhibition in borderline personality disorder and major depression Mareike Ernst a,1 , Harald M. Mohr b, ⁎ ,1 , Margerete Schött a , Constanze Rickmeyer a,b , Tamara Fischmann a , Marianne Leuzinger-Bohleber a , Heinz Weiß a , Ralph Grabhorn b a Sigmund-Freud-Institut, Frankfurt, Germany b Department of Psychiatry, Psychosomatics and Psychotherapy, Goethe University Hospital, Frankfurt, Germany ARTICLE INFO Keywords: Executive function Emotion regulation Cyberball Go/NoGo task Emotional stress Cognitive impairment Personality disorders ABSTRACT It is a prevalent notion that borderline personality disorder (BPD) is characterized by deficits in executive functions (EF) like inhibition. Yet experimental studies yield inconsistent results. However, despite emotional dysregulation being a core feature of BPD, most paradigms did not control for emotional state or comorbid mental disorders. In the present study, subjects with BPD and comorbid MDD (BPD+MDD), with major depression (MDD) and healthy controls (HC) partook in a social exclusion paradigm combined with an inhibition task. We expected inhibition to be more strongly impaired in BPD+MDD than in depression and HC when experiencing negative emotions. Respecting inhibition, depressed patients performed best while (BPD +MDD) patients performed worst. Surprisingly, MDD & HC participants’ performance improved during social exclusion, but this was not the case for BPD+MDD. Inhibition deficits were correlated with childhood trauma. These results challenge the hypothesis that an induction of negative emotion results in inferior inhibition in (BPD+MDD). Instead, patients with (BPD+MDD) seem to suffer from a more general inhibitory dysfunction. Importantly, (BPD+MDD) patients were not able to improve their performance during social exclusion like HC and MDD patients did. These findings need to be investigated further, particularly regarding the efficiency of neural networks regulating inhibition and effects of trauma. 1. Introduction Borderline personality disorder is a debilitating mental illness which encompasses a multitude of symptoms. Core features pertain to emotional stability, interpersonal relations and impulsive behavior (American Psychiatric Association, 2013). In the last years there has been increasing interest in executive dysfunctions (EF) as a possible key moderator in the development of BPD (Judd, 2005; Haaland and Landrø, 2009; Bazanis et al., 2002). A growing body of literature links BPD with impairments of executive functions like planning (Beblo et al., 2006; Dinn, 2004), cognitive flexibility, and inhibition (Rentrop et al., 2007; Black et al., 2009). Yet importantly, there are inconsistent results regarding a deficit concern- ing domains of EF in BPD (for a review see McClure et al., 2015). It has been suggested that comorbid psychopathologies like depression or ADHD could account for the mixed results. Both major depression and ADHD are often characterized by impairments in EF (for depression e.g. Aker et al., 2016; Snyder, 2013; for ADHD e.g. Salomone et al., 2016). What is more, Fertuck et al. (2006) found no differences in performance between depressed patients and depressed patients with comorbid BPD in tests of cognitive flexibility and inhibition, therefore “deficits found in previous BPD samples may reflect their susceptibility to co-occurring MDD”. Furthermore, van Eijk et al. (2015) suggested impairments in response inhibition in patients with BPD when comorbid ADHD is controlled. This was also demonstrated by Lampe et al. (2007). Likewise, a recent study by Krause-Utz et al. (2013) linked response inhibition deficits in BPD with co-occurring ADHD and furthermore emphasized the importance of the assessment of stress levels at the present time. This argument is in accordance with clinical observations and neuropsychological studies which argue that BPD is characterized by emotional dysregulation and impulsivity, wherein emotional responses are inflexible, rigid and overarousing (Linehan, 1993; Putnam and Silk, 2005; Berlin et al., 2005). Despite the fact that disruption in emotion regulation is a core feature in BPD psychopathology, most of the http://dx.doi.org/10.1016/j.psychres.2017.03.034 Received 10 November 2016; Received in revised form 17 February 2017; Accepted 20 March 2017 ⁎ Corresponding author. 1 Both authors contributed equally to this manuscript. E-mail address: Harald.Mohr@kgu.de (H.M. Mohr). Psychiatry Research xxx (xxxx) xxx–xxx 0165-1781/ © 2017 Published by Elsevier Ireland Ltd. Please cite this article as: Ernst, M., Psychiatry Research (2017), http://dx.doi.org/10.1016/j.psychres.2017.03.034