It has been argued that the best way to develop effective psychological interventions is to understand the development and maintenance of the disorder in question, and then to devise treatments that reverse the maintaining mechanisms (Clark, 1997). Such an approach has proven successful in a range of psychological disorders including panic disorder (eg, Clark, 1986), bulimia nervosa (Wilson & Fairburn, 2002), and OCD (Abramowitz, 1997). This chapter first describes the purpose of cognitive-behavioral models of OCD and then goes on to discuss five cognitive-behavioral models that have been proposed to account for OCD symptomatology. Each of these models is presented in detail, and the empirical evidence evaluating them is reviewed. The existing research incorporates a range of methods including questionnaire studies and controlled experimental laboratory research. It is concluded that the data are largely consistent with the cognitive-behavioral approaches, but that important questions remain to be addressed. Implications of these models for the conceptualization and treatment of OCD are also discussed.
THE PURPOSE OF COGNITIVE-BEHAVIORAL MODELSGelder (1997) considered models of psychological disorders to be theoretical schemes for ordering information in a broad and comprehensive way. Such models have two main purposes: First, they provide a means of understanding the development or maintenance of the essential phenomenological aspects of a disorder. In OCD, the cognitive aspects that require explanation include (but are not limited to) (a ) the occurrence of persistent, repetitive intrusive thoughts, images, or impulses, (b) the experience of these thoughts as repugnant and unwanted, and (c) the attempts to ignore or suppress the thoughts. The primary behavioral symptoms in OCD that require explanation are compulsive rituals (eg, handwashing, checking), neutralizing (overt and covert), and avoidance. Related aspects to be explained include why the themes of the obsessions are consistent (ie, aggressive, blasphemous, sexual) and why it is that although 90% of people experience intrusive thoughts of a similar content, only 229