The borderline interpersonal-affective systems (BIAS) model: Extending understanding of the interpersonal context of borderline personality disorder

Prominent explanatory models for borderline personality disorder (BPD) are intrapersonal in nature and hold that it is an emotional disorder. However, the empirical support for emotional models of BPD is mixed. Refinements to BPD explanatory models are needed to increase the precision with which BPD can be understood and treated. Drawing on existing theoretical and empirical research in BPD, this manuscript presents the Borderline Interpersonal-Affective Systems (BIAS) model. The BIAS model purports that harmful early life relationships and subsequent conflictual relationships lead individuals with BPD to develop a sensitivity to interpersonal threat in the form of attentional and appraisal biases. Individuals with BPD are posited to 1) experience heightened emotional reactivity specifically to perceived interpersonal threat and 2) engage in destructive behaviors both to regulate increasing emotion and to meet interpersonal needs. We review the empirical support for each component of the BIAS model, along with the role of the cognitions, emotions, and behaviors of significant others in influencing BIAS model processes in individuals with BPD over time. The BIAS model highlights a novel way of understanding and integrating interpersonal and emotional components of the disorder. Key directives for future research and clinical implications are discussed.