Trustworthiness Appraisal in Borderline Personality Disorder

Abstract

Borderline personality (BPD) is a highly impairing illness with marked instability across multiple domains, including affect, interpersonal functioning, identity, and behavior. Within the past 15 years, researchers have sought to understand and characterize deficits in social cognition that might contribute to or arise from affective or interpersonal dysfunction. The purpose of this dissertation is to understand one aspect of impaired social cognition in BPD: biased trust processing. Individuals with borderline features rate others as less trustworthy in laboratory tasks and act accordingly. However, little is known about the influence of affect on ratings or behavior, or whether biased processing is related to real-world functioning or is merely an artifact of the laboratory. The main study included two groups of participants: (1) individuals who met 3 or more diagnostic criteria for borderline personality disorder (n =30) and (2) a control group of individuals who met 2 or fewer diagnostic criteria (n = 47). An experimental paradigm was used to determine whether affectively arousing information has undue influence on trustworthiness ratings for individuals with borderline features. Individuals with borderline features made more negative trustworthiness appraisals overall. Additionally, negative affective information had more impact on trustworthiness ratings for individuals in the borderline features group relative to the control group. This effect was not mediated by rejection sensitivity or moderated by childhood trauma. A recognition task was used to examine the influence of momentary trustworthiness perceptions on recognition. Overall, individuals who rated faces as less trustworthy during the affective priming task also rated faces as less trustworthy during the recognition task. This indicates some stability in trustworthiness appraisals. Borderline and control groups did not differ in recognition accuracy. However, the borderline group expressed significantly less certainty than the control group about their responses. Incorrect responses in the borderline group, but not the control group, were also rated as less trustworthy than correct responses. Social functioning was examined using multiple measures. A pilot study examined the utility of three new measures of social functioning designed to address perceived flaws in current measures. A group of community participants (N = 100) completed these measures through Amazon’s Mechanical Turk, an online crowdsourcing service. Preliminary findings from this pilot study suggest that these new measures may add meaningfully to our understanding of social functioning impairments in BPD. These new measures were used alongside already validated measures to examine how laboratory-demonstrated trustworthiness processing biases relate to real-world social functioning. Overall, results indicate that despite its reliability and replicability, the finding that individuals with borderline features have biased trustworthiness appraisal may not have much practical significance. Although individuals with borderline features rate others as less trustworthy and act accordingly in laboratory situations, this bias does not translate to real-world social functioning, at least in the current study. Taken together, the findings of the current study show that negative trustworthiness appraisal is a robust and replicable bias in individuals with borderline personality features. Consistent with deficits in frontolimbic regulation of affective influence, this bias is augmentable in the context of negative affective information. However, the bias does not appear to relate to real-world social functioning. Further work is needed to determine whether laboratory-demonstrated trust appraisal biases replicate to more ecologically valid scenarios in which negative trust appraisals may have greater influence on social functioning.