Mentalising and borderline personality traits

Research on eating disorders has increasingly focused on the role of personality traits (Godt, 2008; Millon et al., 1993; Vitousek & Manke, 1994; Vitousek & Stumpf, 2005). Almost 30% of patients with eating disorders meet criteria for a personality disorder (Godt, 2008). Research into personality pathology in adolescents with eating disorders has recognised four main subtypes of personality pathology: a high-

functioning or perfectionist subtype, with minimal personality pathology; an

emotionally dysregulated subtype with borderline and histrionic tendencies; an

avoidant-insecure subtype with anxious, depressed and socially avoidant tendencies;

and a constricted-obsessional subtype with obsessional, compulsive and rigid

tendencies (e.g., Espelage, Mazzeo, Sherman, & Thompson, 2002; Gazzillo et al., 2013; Magallón-Neri et al., 2014; Sansone, Levitt, & Sansone, 2004; Sansone & Sansone, 2011; Thompson-Brenner, Eddy, Satir, Boissueau, & Westen, 2008).

Borderline traits are well reported in patients with eating disorders, particularly those with binge-purge symptoms (Kleifield, Sunday, Hurt, & Halmi, 1994; Lilenfeld et al., 2000; Nagata et al., 2013; Sansone, Chu, Wiederman, & Lam, 2011). Individuals with BN have higher-than-normal comorbidity of Cluster B personality disorders, including BPD (Sansone & Sansone, 2011; Rowe et al., 2008; Selby et al., 2012). Sansone et al. (2005) conducted a meta-analysis and found that BPD was the most frequent comorbid personality disorder among both AN-BP (25%) and BN (28%) sufferers. Among outpatients with BN, BPD is associated with more generalised

psychiatric symptoms (Steiger & Stotland, 1996). The presence of BPD traits in patients with eating disorders complicates their clinical presentation, and presents unique

challenges for treatment (Robinson et al., 2014). These patients present with weight loss, bulimia, self-harm, emotional lability and impulsive behaviours. In a treatment trial, this group remained more clinically severe during and after treatment compared to controls without borderline traits, and held more maladaptive attitudes and a stronger drive for thinness throughout treatment (Steiger & Stotland, 1996).

Within an attachment paradigm, the mentalising model of BPD (Fonagy & Bateman, 2004; Fonagy & Luyten, 2009; Sharp & Fonagy, 2008) proposes that failures in attachment lead to the unstable or reduced mentalisation that is characteristic of BPD.

BPD is a psychiatric condition that involves instability of affect and identity, impaired interpersonal relationships, and self-injurious behaviour (Sharp, Kalpakci, Mellick, Venta, & Temple, 2014). Originally considered limited to adults, recent longitudinal and genetic studies have established that BPD is a valid diagnosis for adolescents (Bornovalova, Hicks, Iacono, & McGue, 2009; Miller, Muehlenkamp, & Jacobson, 2008). There has been a recent move towards studying borderline as personality traits rather than a diagnostic status, particularly in adolescent research (Sharp et al., 2014). Borderline tendencies include impulsivity, sensation-seeking, interpersonal sensitivity, affective dysregulation, stress reactivity, passive disengagement, self-harm and suicidal thoughts (Kleifield et al., 1994; Lilenfeld et al., 2000; Millon et al., 1993; Sadeh et al., 2014; von Lojewski, Fisher & Abraham, 2013). Fonagy and Bateman suggested that not only is a lack of mentalisation one of the hallmarks of BPD, but that the self-harm associated with BPD is a symptom of reduced mentalising capacity.

Research on the mentalising capacities of patients with BPD has revealed mixed results. Fertuck et al. (2009) found that adults with BPD scored higher on a mentalising test measured by the Reading the Mind in the Eyes task (Baron-Cohen et al., 2001). The authors suggested that patients with BPD may have an enhanced sensitivity to the mental states of others, and this may contribute to social difficulties in patients with BPD. Preißler et al. (2010) used the Reading the Mind in the Eyes Task to test explicit mentalising, and the Movie for the Assessment of Social Cognition (Dziobek et al., 2006) to test implicit mentalising abilities of adults with BPD. The study found no difference between healthy controls and participants with BPD on the Eyes task, but participants with BPD demonstrated significant impairments in mentalising on the Movie for the Assessment of Social Cognition. These results indicate that patients with BPD may display deficits in implicit mentalising, while displaying superior explicit

mentalising. In a similar vein, patients with BPD have been found to display a

difference in mentalising capacity between affective and cognitive mentalising. Unlike healthy controls, people with BPD display higher affective mentalising abilities

compared to cognitive mentalising abilities (Harari, Shamay-Tsoory, Ravid, & Levkovitz, 2010).

In line with the available evidence on mentalising deficits in adults with BPD, there is evidence that adolescents presenting with BPD features also display deficits in mentalising capacity, specifically excessive mentalising, rather than under-mentalising. Bleiberg (2013) offered a description of the clinical presentation of adolescents who hypermentalise. He reported that adolescents, particularly those with emerging BPD, may present with unreflective, rigid, automatic assumptions that are maintained with certainty about the states of mind of themselves or others. Such adolescents frequently place a large emphasis on overwhelming affective states. Bleiberg stated that this presentation is most often seen in the context of stress related to attachment, which can be quickly hyperactivated, creating a situation where they may engage in

hypermentalising (excessive and usually inaccurate attempts to interpret other people’s mental states).

Sharp et al. (2011) investigated mentalising and emotion regulation in

adolescent inpatients diagnosed with BPD. Mentalising was measured using the Movie for the Assessment of Social Cognition (Dziobek et al., 2006). Results identified that, rather than decreased mentalising abilities, these adolescents displayed

hypermentalising. The study found that adolescents who met criteria for BPD had a higher frequency of over-mentalising responses: they made assumptions about other people’s mental states that went beyond observable information provided. This indicates an over-attribution of mental states to others, and likely their misinterpretation (Sharp et

al., 2013). The study also found that hypermentalising interacted with emotional regulation; as these adolescents misunderstood other people’s minds, it led to distress and difficulty regulating emotions, which increased symptoms.

Sharp et al. (2013) examined whether inpatient-based mentalising interventions would serve to decrease hypermentalising in a sample of adolescents diagnosed with BPD, compared to a sample of psychiatric controls. This study confirmed a relationship between borderline traits and symptoms and hypermentalising. Hypermentalising was measured by the Movie for the Assessment of Social Cognition, as well as the Child Eyes Test, Basic Empathy Scale and the MSTA. After the intervention, results indicated that hypermentalising was significantly reduced between admission and discharge for both BPD and non-BPD groups. The correlation between the change in

hypermentalising score and the change in borderline symptoms was highly significant, indicating that hypermentalising was associated with a change in borderline symptoms.

While the study did not find a significant improvement in hypermentalising measured by the MSTA, it did find a significant relationship between hypermentalising measured by the MSTA and measured by the MASC, indicating that hypermentalising measured by the MSTA may be tapping a similar construct as hypermentalising on the MASC (Sharp et al., 2013). In support of these findings, Rossouw (2013b) found in a cross-sectional study of self-harming adolescents that patients with borderline

symptoms displayed decreased mentalising capacity using the HIF measure (Sandell et al., 2008) compared to non-clinical controls, but not compared to clinical controls of adolescents with other mental health difficulties. Although those in the self-harming group were significantly more depressed, Rossouw did not control for depression in her analysis.