Thought suppression and its effects on thought frequency, appraisal and mood state in individuals with obsessive-compulsive disorder.

Leading models of obsessive-compulsive disorder (OCD) implicate thought suppression as a key factor in the escalation and persistence of the disorder. This experiment examined the effects of suppression on the frequency of obsessional thoughts in 50 individuals with a primary diagnosis of OCD, and also investigated the effects of participants' appraisals regarding their failures in thought control on distress about intrusive thoughts and on mood. Participants' most upsetting obsessional thought was primed and they then monitored its occurrence over two 4-min intervals. In the first interval, half of the participants were instructed to suppress their obsessional thought and half were instructed not to suppress any thoughts. In the second interval, all participants were given the 'Do Not Suppress' instructions. Participants rated their suppression effort and discomfort over thought occurrences after each interval and recorded their appraisals of thought recurrences during the first interval. Mood state was then reassessed. No ironic effect of suppression on frequency was noted. However, negative appraisals of thought recurrences were associated with more discomfort over thought occurrences and more negative mood at Time 2. These findings suggest that interpretations regarding failures in thought control may be of central importance in understanding obsessional problems.