Die Bedeutung von Metakognitionen bei Zwangsstörungen

According to cognitive models of obsessive-compulsive disorder (OCD), dysfunctional cognitive beliefs (e.g., inflated responsibility) contribute to the development and maintenance of the disorder, whereas the metacognitive approach by Wells (1997) takes the perspective that dysfunctional metacognitive beliefs (e.g., beliefs about the power of thoughts) play the central role in the development of the disorder. This dissertation aims to investigate the relevance of metacognitive beliefs to obsessive-compulsive (OC) symptoms and related impairments, in order to clarify the importance of the metacognitive approach in more detail. An important precondition for investigating the relevance of metacognitions is a valid and reliable measurement of these constructs. The OC-specific metacognitive beliefs of thought-action fusion are measured by the “Thought Action Fusion scale” (TAF scale). The structure and psychometric properties of a German version of this measure were assessed (study 1). The original structure was replicated using exploratory and confirmatory factor analyses, the reliability was satisfactory to very good and the validity was partly satisfactory. The TAF scale could discriminate between clinical and nonclinical samples, but not between different clinical samples. A second study aimed to investigate the relevance of OC-specific metacognitions such as thought fusion beliefs, positive beliefs about rituals and inappropriate stop signals for OC symptoms (study 2). Results indicated that a group of patients with OCD reported significantly more positive beliefs about rituals and stop signals than did three other (non)clinical groups. No differences were found for thought fusion beliefs. In the sample of patients with OCD, each OC-specific metacognition explained incremental variance in OC symptoms, even when controlling for cognitive beliefs and general, non OC-specific metacognitions. A third study aimed to investigate emotion-related effects and the influence of metacognitive beliefs in verbal-episodic memory in relation to high checking (study 3). Higher checking was related to better memory performance for a checking-related story as compared to two neutral stories. However, higher checking was also related to higher rates of forgetting of OC-specific material over a delay period. Rates of forgetting in relation to checking were mediated by the metacognitive belief of cognitive confidence. To conclude, the findings of this dissertation suggest a relevance of (OC-specific) metacognitions to OCD. Methods of the metacognitive therapy might address these beliefs and thereby lead to a reduction of both OC symptoms and cognitive impairment.