Repeated checking really does cause memory distrust.

Memory phenomena associated with obsessive-compulsive disorder (OCD) have received increased attention in the recent literature. Some debate remains about whether OCD is characterized by deficits in memory per se, or by poor memory confidence. Following from a recent study that demonstrated memory distrust results from repeated checking of a virtual computerized stove, we asked 50 undergraduate students to repeatedly turn on, turn off and check either a real kitchen stove (relevant checking) or a real kitchen faucet (irrelevant checking) in a standardized, ritualized manner. All participants completed a final check of the stove following these 19 checking trials. Results indicated that following repeated relevant checking, participants reported significantly reduced memory confidence, vividness and detail. Repeated irrelevant checking did not produce these decreases. Results are discussed in terms of cognitive-behavioural formulations of OCD and in terms of the effects of repetition on memory and metamemory.