Exploring the relationships among impulsivity, interpersonal difficulties, and social risk-taking in borderline personality disorder: behavioural influences and neural correlates

Abstract

Impulsivity and difficulty maintaining interpersonal relationships (interpersonal difficulties) are two symptoms characteristic of borderline personality disorder (BPD). Past work has shown that these symptoms may have differential effects on risk-taking behavior: impulsivity has been associated with increased risk-taking, while interpersonal difficulties has been associated with decreased trust in social contexts, which can be construed as decreased risk-taking behavior. More work is needed to understand how these symptoms are related to monetary risk-taking in social contexts. The goal of this dissertation is to better understand the relationships symptoms of impulsivity and interpersonal difficulties have with monetary risk-taking in a social context in individuals displaying a range of BPD features (Study 1) and individuals with BPD (Study 2). This dissertation further seeks to elucidate the neural correlates of social risk-taking as they pertain to these sets of symptoms in individuals with BPD (Study 3). Study 1 finds that individuals with increased symptoms of impulsivity are less sensitive to the difference between two gambles' risks, and individuals with increased symptoms of interpersonal difficulties are less sensitive to the difference between two gambles' risks only in a social context. Study 2 finds that individuals with increased symptoms of impulsivity are less sensitive to the difference between two gambles' risks, and individuals with increased symptoms of interpersonal difficulties are less sensitive to the difference between two gambles' risks regardless of context. Study 3 finds that individuals with BPD show decreased anterior insula response to the difference in risk between the gamble they select and the unchosen gamble, though it did not find a relationship between insula response and BPD symptoms. Together, these studies show that individuals with BPD respond differently to monetary risk-taking than individuals without BPD. This work suggests symptoms of impulsivity and interpersonal difficulties may be new targets for behavioral interventions to treat BPD.