Check, check, double check: checking the autopilot causes distrust: Experimental studies on the effects of compulsive perseveration

Abstract

Obsessive-compulsive disorder (OCD) is characterized by persistent doubt. The majority of patients with OCD engage in repeated checking to reduce these feelings of uncertainty. However, numerous studies demonstrated that repetitive behavior ironically increases uncertainty: perseverative checking increases memory uncertainty, staring induces uncertainty about perception, compulsive cleaning leads to uncertainty about contamination, and repeating sentences induces uncertainty about the meaning of the sentence. Apparently, perseverative behavior is counterproductive and patients with OCD easily end up in a vicious circle: to reduce feelings of uncertainty they engage in perseverative behavior, but this paradoxically increases uncertainty, which again induces compulsive perseveration. OCD is a disabling disorder with severe impairments in daily functioning. Patients with OCD spend almost 10 years of their lives with this disorder, engaging in obsessive-compulsive behavior multiple hours a day. The first aim of Eliane Dek’s dissertation was to examine whether the effects of repeated checking on memory are domain specific, or whether perseverative checking also affects confidence in attention and perception. Healthy participants performed a checking computer task in which they activated, deactivated and checked threat-irrelevant stimuli. The results indicated that repeated checking reduces meta-memory (i.e., memory confidence, vividness, and detail), while memory accuracy remained unaffected. Confidence in perception did not reduce after repeated checking. Confidence in attention reduced slightly, but because attentional focus actually is reduced after repeated checking the reductions in attentional confidence may be considered to be a ‘general’ phenomenon. The second aim was to study if automatization could be a mechanism underlying the effects of repeated checking. To test this, the checking task was extended with a secondary reaction time (RT) task. In the pre- and post-test of this checking/RT dual task, participants performed checks while simultaneously responding to tones. First, we tested whether checking behavior automates as a result of repetition and increased familiarity with the checked stimuli. Second, we proposed that defamiliarization, by modifying the perceptual characteristics of the stimuli, leads to de-automatization. Third, we examined whether defamiliarization could attenuate the effects of checking on meta-memory. The results demonstrated that the negative effects of repeated checking are associated with automatization of checking behavior. Although strong defamilarization increased memory confidence, the results on defamiliarization were not straightforward. The data suggested that defamiliarization may not only affect automatization, but can also directly affect meta-memory. Further research into the influence of (de)automatization and defamiliarization on the ‘perseveration à uncertainty’ cascade needs to be conducted to unravel the mechanism underlying this paradoxical phenomenon. The third aim of this thesis was to test if the findings on perseveration effects generalize to stimuli that are unrelated to threat, and whether the perseveration effects occur in a clinical sample. The results indicated that the perseveration phenomenon is a general phenomenon: the negative effects of perseverative behavior are not bound to stimuli that are related to OCD concerns. Furthermore, there were no differences in the effect of perseveration on meta-memory, or the degree of automatization of checking behavior, between patients with OCD and healthy controls.