BRIEF REPORT CHANGES IN DEFENSIVE FUNCTIONING IN A CASE OF AVOIDANT PERSONALITY DISORDER MICHELLE D. PRESNIAK University of Saskatchewan TREVOR R. OLSON McGill University JOHN H. PORCERELLI Wayne State University School of Medicine V. BARRY DAUPHIN University of Detroit Mercy This case study is based upon data from a male patient with Avoidant Personality Disorder who was in psychoanalytic treatment for 5 years. Defense mecha- nism use was assessed by 3 coders using the Defense Mechanisms Rating Scales. Session transcripts from intake, each year of therapy, and 1-year follow-up were used for the ratings. Over the course of psychoanalysis and follow-up, the pa- tient’s Overall Defensive Functioning and High-Adaptive defense level use in- creased and his use of the Disavowal defense level and Fantasy decreased. The pattern of change throughout treatment was also assessed. The patient’s Overall Defensive Functioning decreased initially, followed by an increase through year 4. Overall Defensive Functioning decreased again prior to termination before increas- ing to its highest level at follow-up. The results demonstrated changes consistent with hypotheses and theory, including overall improvement in defensive func- tioning, an initial regression of defensive functioning, decline in functioning imme- diately prior to termination, and contin- ued improvement posttermination. This pattern of defense change highlights the importance of assessing defenses in treat- ment research. Keywords: defense mechanisms, Avoidant Personality Disorder, psycho- analysis In 2007, Porcerelli and colleagues published the first systematic case study of a psychoanalytic treatment of Avoidant Personality Disorder (AvPD). Change was assessed with measures of personality, psychosocial functioning, object re- lations, general psychopathology symptoms, and AvPD symptoms. The patient, Mr. A, experi- enced significant improvements at termination, and these gains were maintained at 1-year follow- up. The goal of the current study was to reexam- ine this case for changes in defensive functioning across treatment and follow-up. Defense mechanisms are unconscious mental operations that alleviate stress and anxiety. The development of defenses is a healthy phenome- non that begins early in life (Cramer, 2006). Defenses are considered adaptive if they are ap- Michelle D. Presniak, Department of Psychology, University of Saskatchewan; Trevor R. Olson, Institute of Community and Family Psychiatry at SMBD Jewish General Hospital, Depart- ment of Psychiatry, McGill University; John H. Porcerelli, De- partment of Family Medicine & Public Health Sciences, Wayne State University School of Medicine; V. Barry Dauphin, Depart- ment of Psychology, University of Detroit Mercy. Michelle D. Presniak is now at the Institute of Community and Family Psychiatry at SMBD Jewish General Hospital, McGill University. The study was funded in part by the American Psychoan- alytic Association Fund for Psychoanalytic Research (John H. Porcerelli, Principal Investigator). Correspondence regarding this article should be addressed to Michelle D. Presniak, PhD, ICFP Jewish General Hospital, 4333 Chemin de la Cote Ste-Catherine, Montreal, Quebec, H3T 1E4, Canada. E-mail: Michelle.Presniak@usask.ca Psychotherapy Theory, Research, Practice, Training © 2010 American Psychological Association 2010, Vol. 47, No. 1, 134 –139 0033-3204/10/$12.00 DOI: 10.1037/a0018838 134