Emotion regulation (ER) often happens in social contexts but research on interpersonal ER is still scare. This study aimed to investigate the impact of interpersonal ER strategies on emotional...Show moreEmotion regulation (ER) often happens in social contexts but research on interpersonal ER is still scare. This study aimed to investigate the impact of interpersonal ER strategies on emotional working memory (eWM) performance, particularly focusing on individuals with borderline personality disorder (BPD). The study hypothesized that ER domains, specifically those addressing negative affect, adversely affect eWM performance and that the presence of BPD would moderate this relationship. This within-subject, experimental study involved 164 participants, with complete data from 89 individuals (68 females, mean age 25.30 ± 4.16 years). BPD was assessed by trained clinicians using the International Personality Disorder Examination. Participants completed the Interpersonal Emotion Regulation Questionnaire and an Emotional Working Memory Task (EWMT) featuring emotionally arousing stimuli as distractors. Linear regression analyses were conducted to examine the predictive and moderating effects of interpersonal ER strategies and BPD on eWM performance. The study found opposite effects of what was originally hypothesized: the Perspective Taking domain of ER significantly predicted eWM performance. This relationship was moderated by BPD: individuals with BPD and higher scores on the Perspective Taking scale experienced less distraction during the EWMT in the presence of emotional facial stimuli, while there was no significant difference for controls. Additionally, Enhancing Positive Affect negatively influenced eWM performance, suggesting that higher scores in this domain were associated with increased distraction by emotional stimuli. However, no significant effects were found for the Soothing and Social Modeling domains. The findings highlight the importance of not only considering intrapersonal but also interpersonal ER strategies in understanding and treating emotional dysregulation in BPD. Integrating computer-based eWM training programs and interpersonal ER strategies into therapeutic approaches may enhance cognitive control and emotional regulation in individuals with BPD.Show less