Identity Pathology and Mentalization Deficits: An Attempt to Support Clinical Theory With Data

An extensive theoretical literature links identity pathology with deficits in mentalization, which is the ability to understand the internal mental states of self and others. However, only a few investigations have attempted to bridge theory and data by empirically testing the relation between mentalization and identity pathology, and none have done so with mentalization measured using a laboratory task. The current study investigated the association between mentalization deficits and identity pathology in a large, nonclinical sample. Participants (N = 305) completed a self-report measure assessing identity pathology and a laboratory task assessing mentalization ability. Whereas the existing theoretical literature would argue for a robust association between identity pathology and mentalization impairment, our results revealed essentially no association between identity pathology and mentalization impairment. Moreover, we found essentially no association between identity pathology and any of a number of specific mentalization deficits in our sample. Our findings failed to provide empirical support for the clinical and theoretical literature linking mentalization and identity pathology. Given our adequate statistical power to detect even relatively small associations, we offer these findings to advance theoretical and methodological discussion in this important area. We discuss the implications of these null findings, particularly attuned to the possibility that a link between mentalization impairment and identity pathology may be more complicated than hypothesized. We also consider that these results might be related to methodological features of our study (e.g., self-report and laboratory measures; the range of mentalization impairment in our sample).