The Effect of a Defusion Exercise Including a Hierarchical Procedure on Depressive Rumination

This study examined the effect of a defusion exercise with a hierarchical procedure in the context of depression, depressive rumination, and behavioral inflexibility. A total of 38 undergraduates were randomly assigned to either a defusion or control group. All participants answered questionnaires and engaged in a behavioral flexibility task before and after intervention. For the intervention, the defusion group engaged in a hierarchical defusion procedure. They sorted their depressive private events into either thoughts, feelings, or sensations, and all of them were integrated to “depression.” Subsequently, they engaged in word‐repetition exercises for “depression.” The control group read an emotionally neutral article on Japanese culture for 5 min. Results showed that the defusion exercise decreased cognitive fusion regarding depression. However, it did not decrease depressive rumination or promote behavioral flexibility. These results suggest that adjustments in the implementation of defusion exercises and other interventions may be necessary to reduce depressive rumination and promote behavioral flexibility.