Etiology of Obsessive Beliefs: A Behavioral-Genetic Analysis

Abstract

Contemporary cognitive models of obsessive-compulsive disorder, derived from Beck’s cognitive approach to emotional disorders, emphasize the importance of particular dysfunctional beliefs in giving rise to obsessive-compulsive (OC) symptoms. These beliefs represent three factor-analytically distinct domains: (a) The overimportance of one’s thoughts and the need to control these thoughts; (b) perfectionism and the intolerance of uncertainty; and (c) inflated personal responsibility and the overestimation of threat. The models suggest that these beliefs arise from environmental factors, such as exposure to particular forms of learning. To test this assumption, we conducted a behavioral-genetic analysis of scores on these dysfunctional beliefs from a community sample of 167 monozygotic and 140 dizygotic twin pairs. Results indicated that the beliefs are significantly heritable, with genetic factors accounting for 32% to 40% of the variance in scores. Over two-thirds of the variance in scores for the three types of beliefs was attributable to a set of genetic and environmental factors that influenced all of these beliefs. Results suggest that contemporary cognitive models require revision, because they erroneously attribute the development of OC-related dysfunctional beliefs entirely to environmental factors.