OCD and Cognitive Illusions

Evidence suggests that obsessive-compulsive disorder (OCD) could be associated with cognitive biases and deficits, and such deficits may inform us about characteristic OCD thinking and behaviour. Information processing research has suggested, for example, that mnestic and executive dysfunctions (Greisberg and McKay, in Clin Psychol Rev 23:95-117, 2003), may account for organizational problems. Lack of cognitive flexibility in problem-solving (Chamberlain et al., in Am J Psychiatry 163:1282-1284, 2006; Chamberlain et al., in Am J Psychiatry 164:335-338, 2007) and decision-making (Volans, in Br J Social Clin Psychol 15:305-317, 1976; Fear and Healy, in Psychol Med 27(1):199-208, 1997) may encourage hesitancy. In this contribution we review the role of common cognitive illusions in OCD. Although found in the general population, cognitive illusions, particularly when present in combination, could help our understanding of the origin and the maintenance of OCD. We focus discussion on thinking illusions (conjunction fallacy, confirmation bias, illusory correlation, illusion of control, biases in deductive and causal reasoning), judgement illusions (availability and representativeness, anchoring effect, validity effect), and memory illusions (associative memory illusions, effects of labelling and misinformation effect) and their relationship with OCD. In conclusion, we draw some clinical implications and suggestions.