Treating disgust reactions in contamination-based obsessive-compulsive disorder.

Contamination fear associated with obsessive-compulsive disorder (OCD) has features that strongly suggest it is based in part on disgust. In particular, sympathetic magic, or the tendency for disgust-evoking stimuli to transfer that property to previously neutral stimuli, is common in contamination fear. Treatment for OCD typically involves exposure with response prevention for feared stimuli. Unexamined, however, has been the habituation for specific disgust stimuli among individuals with contamination fear. This study is a preliminary investigation with a group of primary contamination fearful participants diagnosed with OCD (C-OC; n = 9) compared to a group with primarily other symptoms of OCD (O-OC; n = 8). All participants were exposed to a set of disgust stimuli that were not associated with anxiety reactions for 30 min across five sessions, and exposed to anxiety-evoking stimuli specific to their OCD symptoms for 30 min. Comparisons showed that, while both groups had reduced disgust reactions, the C-OC group habituated more slowly and to a lesser degree than the O-OC group. No differences existed between the groups for anxiety reduction. The findings suggest that contamination fear is based in part on disgust reactions, and that disgust is amenable to exposure-based interventions.