Studying defensive styles is typically associated with dynamic theory and therapy. The present study was designed to examine the efficacy of adding two individual sessions of Motivational Interviewing (MI) and Thought Mapping (TM) to cognitive-behavioral group therapy (CBGT) to promote changes in the use of defense mechanisms among obsessive-compulsive disorder (OCD) patients.

Forty outpatients meeting OCD DSM-IV criteria were randomly assigned to either a MI+TM group or a control group, before 12 weekly CBGT sessions. To evaluate changes in defense mechanisms, the Defense Style Questionnaire (DSQ) was administered before and after treatment.

The use of the mature defense mechanisms increased in the MI+TM group at post-treatment, and there were significant differences in the decrease of use of the neurotic defense mechanisms. In addition, patients who achieved full remission differed in the use of the immature defense mechanisms. The control group presented no significant decrease in the use of any defense mechanisms.

These findings suggest that adding two individual sessions of MI and TM to CBGT can facilitate changes in use of defense mechanisms in OCD adult outpatients, as measured by a specific instrument.