The role of defense mechanisms in borderline and antisocial personalities.
We examined whether borderline personality disorder (BPD) and antisocial personality disorder (APD) could be differentiated based on defense mechanisms as measured by observer (Defense-Q; MacGregor, Olson, Presniak, & Davidson, 2008) and self-report (Defense Style Questionnaire; Andrews, Singh, & Bond, 1993) measures. We conducted 2 studies whereby nonclinical participants were divided into borderline and antisocial groups based on scores from the Personality Assessment Inventory (Morey, 1991). Multivariate analysis of variance results revealed significant overall group differences in defense use. Univariate analyses further showed group differences on several individual defenses (e.g., acting out, denial, and turning against self). Together, the findings suggest that in BPD, the defenses may emphasize interpersonal dependency and a tendency to direct aggression toward the self; whereas in APD, the defenses may emphasize egocentricity, interpersonal exploitation, and a tendency to direct aggression toward others. Overall, this study demonstrates important differences in defense use between borderline and antisocial personality groups across both observer and self-report measures.
Institute of Community and Family Psychiatry at SMBD Jewish General Hospital, Department of Psychiatry, McGill University, Montreal, Quebec H3T 1E4, Canada. michelle.presniak@usask.ca
Michelle D
MD
Presniak
Trevor R
TR
Olson
Michael Wm
MW
Macgregor
D000328:Adult; D000374:Aggression / Q000523:psychology; D000704:Analysis of Variance; D000987:Antisocial Personality Disorder / Q000175:diagnosis / Q000523:psychology*; D001883:Borderline Personality Disorder / Q000175:diagnosis / Q000523:psychology*; D003674:Defense Mechanisms; D005260:Female; D006801:Humans; D008297:Male; D008960:Models, Psychological; D015999:Multivariate Analysis; D010555:Personality Inventory