Borderline personality disorder (BPD) is associated with the use of maladaptive emotion regulation (ER) that predicts unstable interpersonal relationships and emotion dysregulation. Rumination, a maladaptive cognitive ER response, may be one mechanism by which those with BPD experience emotion dysregulation. However, it remains unclear whether emotion dysregulation is linked to rumination in general, or to rumination during interpersonal situations that often prove challenging for those with BPD. The present study examined whether interpersonal exclusion conferred an increased risk to spontaneously ruminate among those with elevated BPD features relative to an impersonal negative mood induction, and whether spontaneous rumination mediated the effects of BPD features on distress reactivity. Overall, BPD features predicted stronger tendencies to spontaneously ruminate and higher levels of distress following interpersonal exclusion; spontaneous rumination following interpersonal exclusion mediated the effects of BPD features on distress. These findings highlight the importance of context when examining ER outcomes.
Keywords: borderline personality disorder; context; emotion regulation; interpersonal exclusion; rumination.