Abstract
BACKGROUND: In recent studies, the deficit in the cognitive process has been investigated as one of the etiological hypotheses in a wide range of obsessive-compulsive disorders (OCD). This study aimed to compare the effectiveness of acceptance and commitment therapy (ACT) and metacognitive therapy (MCT) on objective cognitive information processing style in obsessive-compulsive patients. MATERIALS AND METHODS: This quasi-experimental study with a pre-test and post-test plan and a control group was conducted on 45 patients with OCD, matched with gender, age, and educational and marital status. The samples in three groups were selected using the convenience sampling method. Finally, the study participants were randomly divided into two experimental groups and one control group and assessed using Pacini and Epstein's rational experimental Inventory (REI) in two stages, pre-test, and post-test. The experimental groups received ACT and MCT weekly during eight and seven sessions and in a group. RESULTS: The results showed that ACT and MCT are effective at a significant level in the objective cognitive information processing style of obsessive-compulsive patients (P < 0.05). The post-test results showed that the effect of ACT in changing rational processing style is more effective than MCT treatment. Also, the effect of ACT on intuitive processing style changes was greater than on MCT treatment. CONCLUSION: The findings of this study indicate that ACT and MCT cause a significant change in intuitive style to rationalism in the thematic processing of cognitive information of obsessive-compulsive patients. According to the results, both methods of treatment improve the research variables in these patients.