Can defense mechanisms aid in our differentiation of borderline and antisocial personalities?

Abstract

Goal: The aim of the current studies was to evaluate the ability of individual defenses to differentiate Antisocial (APD) and Borderline (BPD) personalities. Because multiple defense measures were utilized, Study 1 was dedicated to evaluating the convergent validity between the measures used: Defense Style Questionnaire (DSQ), Defense-Q, and Defense Mechanism Manual (DMM). Studies 2, 3, and 4, then evaluated the ability of the defenses to differentiate APD and BPD groups. Method: In Study 1, participants completed all defense measures and correlations were conducted between the individual defenses. In Studies 2, 3, and 4, groups of nonclinical participants were divided into APD and BPD groups based on scores from the Personality Assessment Inventory. They also completed the DSQ (Studies 2, 3, & 4), the Defense-Q (Study 3), and/or the DMM (Study 4).The groups were then examined for differences on defenses using MANOVA and DFA analyses. Results: Results from Study 1 revealed no significant correlations between the measures for any of the individual defenses. In Studies 2, 3, and 4, DSQ and Defense-Q results revealed that defenses were able to differentiate the APD and BPD groups, but the DMM results did not replicate these findings. Univariate analyses showed that many defenses differed between the groups (e.g., Acting Out, Denial, and Turning Against Self), while others showed no differences (e.g., Idealization). Conclusion: The results were discussed in relation to previous theory and research. The findings provided support for many theoretical expectations. For example, the results supported: Kernberg (1984) who posited both groups would use primitive defenses (e.g., Splitting, Denial); Perry and Cooper (1986) who posited BPD groups would internalize negative views towards the self; and Gacono and Meloy (1988) who believed Denial was characteristic of APD. Overall, the results suggested that APD and BPD groups demonstrated differences in defense use.