Shenakht Journal of Psychology & Psychiatry

Introduction: Borderline personality disorder (BPD) is characterized by emotional instability, impulsivity, and interpersonal difficulties. Rejection sensitivity and deficits in inhibitory control are considered major factors contributing to the persistence of BPD symptoms. Examining these constructs can provide a better understanding of the underlying mechanisms and guide the development of more effective interventions.
Aim: The present study aimed to model borderline personality disorder symptoms based on rejection sensitivity, with inhibitory control as a mediating variable.
Method: This descriptive-correlational study was conducted on all students of Mohaghegh Ardabili University during 2021–2022. A sample of 153 participants was selected through multistage cluster random sampling (according to Kline’s rule, a sample size of 153 was sufficient for structural equation modeling). Data were collected using the Borderline Personality Scale (STB), the Rejection Sensitivity Questionnaire, and the Go/No-Go Task. Analyses were performed using regression and structural equation modeling with SPSS 28 and SmartPLS 3.
Results: Findings indicated that the overall model had a good fit. Rejection sensitivity had a positive and significant effect on borderline symptoms (β = 0.36), while inhibitory control showed a negative and significant effect (β = −0.33). Moreover, the mediating role of inhibitory control in the relationship between rejection sensitivity and borderline symptoms was confirmed (β = 0.12).
Conclusion: These results suggest that rejection sensitivity plays a crucial role in the emergence and persistence of borderline symptoms, while inhibitory control mediates this relationship. Thus, reducing rejection sensitivity and enhancing inhibitory control may serve as essential components in therapeutic interventions aimed at alleviating BPD symptoms.