The present study aimed to fill a gap in empirical research on insufficiently understood core features of borderline personality disorder (BPD) and the mechanisms linking them. A statistical model which distinguishably centers dissociative experiences was tested. Specifically, it was examined whether dissociation mediates the relationship between mentalization and chronic feelings of emptiness in individuals self-reporting a BPD diagnosis, using two distinct measures of emptiness.

A total of 67 participants self-reporting a BPD diagnosis completed a set of standardized self-report measures assessing mentalization (MentS), dissociation (DESR-PL), and chronic emptiness (SES, CSV). Data were analyzed using Spearman correlations and mediation analysis with bootstrapping (PROCESS macro), controlling for age, gender, and duration of diagnosis. Critically, sample selection limits generalizability of the findings.

The results revealed significant negative associations between mentalization and both dissociation and chronic emptiness, alongside a strong positive relationship between dissociation and emptiness. Mediation analyses demonstrated that dissociation significantly mediated the relationship between mentalization and chronic emptiness. In most models, full mediation was observed, indicating that deficits in mentalization predicted increased feelings of emptiness primarily through elevated dissociative experiences. Mentalization focused on the self emerged as a particularly strong correlate of both dissociation and emptiness.

These findings suggest that dissociation may constitute a key psychological mechanism linking impaired mentalization to the feelings of emptiness in BPD. Results could use as a prompt for asking further research questions about the importance of targeting dissociative processes in psychotherapy, alongside enhancing mentalization capacities.