Intimacy in close relationships and borderline personality features: the importance of traumatic childhood experiences, rejection sensitivity, and first-impression social judgments for attachment security

BACKGROUND: Intimacy, feeling close to others, and mutual trust and regard are important aspects of a secure attachment style that contributes to stable relationships. Difficulties experiencing intimacy have been linked to traumatic childhood experiences, such as abuse and neglect, rejection sensitivity (RS), and borderline personality disorder (BPD). In experimental studies, patients with BPD perceived unfamiliar faces as less trustworthy and detected less positive cues of happiness, social affirmation, and inclusion. However, it remains unclear whether social-cognitive judgments of unfamiliar faces predict attachment-related intimacy beyond BPD features, childhood trauma, and RS. OBJECTIVE: This study aimed to simultaneously investigate the predictive effects of BPD features, childhood trauma, RS, and first-impression social-cognitive judgments of trustworthiness and happiness on intimacy in close relationships, beyond romantic relationships. Additionally, we investigated whether the association between BPD features and attachment-related intimacy is moderated by childhood trauma, RS, and first-impression social judgments. METHODS: In an online study, 509 women completed questionnaires on intimacy in close relationships (subscales of the Adult Attachment Scale Revised), BPD features (Personality Assessment Inventory Borderline Features Scale), childhood trauma (Childhood Trauma Questionnaire Short Form), and RS (Adult Rejection Sensitivity Questionnaire). Additionally, they evaluated happiness and trustworthiness in unfamiliar female faces. Hierarchical linear regression analysis with intimacy as outcome tested the predictive strengths of all variables including interactions with BPD features. RESULTS: Higher BPD features, childhood trauma, particularly emotional neglect, and RS, as well as lower trustworthiness impressions predicted less intimacy in close relationships. Despite their interrelations, all predictors except happiness ratings showed unique predictive effects on intimacy. Interaction effects were not significant. DISCUSSION: Findings support the importance of BPD features, childhood trauma, and RS for experiences of closeness and connection in adult attachment relationships. Additionally, findings provide first evidence for a small direct link between trustworthiness evaluations of unfamiliar faces and lower experiences of intimacy. Future research should investigate these associations in clinical samples including both women and men to further understand whether trustworthiness impressions could be an important socio-cognitive mechanism and potential treatment target.