Metacognition that a cognitive task disrupts subsequent recognition causes the revelation effect

Engaging in a cognitive task prior to making a recognition judgment increases the probability of ‘old’ responses—termed the revelation effect. The occurrence mechanism of this effect has not been clarified despite 30 years of studies. To reveal the mechanism, we examined the validity of the criterion shift by metacognition account—metacognition that a cognitive task disrupts a subsequent recognition judgment causes a liberal criterion shift and the revelation effect occurs, and vice versa. In Experiment 1, to provoke the metacognition that a cognitive task would make subsequent recognition easy, words that were easy to recognise were used after the cognitive task. In Experiment 3, conversely, difficult words were used after the task. In Experiment 2, word difficulty was not manipulated. The results showed that the degree of the revelation effect increased linearly from Experiment 1 to Experiment 3 as a function of word difficulty. These results suggest metacognition is related to the revelation effect, and the validity of the criterion shift by metacognition account was confirmed. This study sheds new light on the study of the revelation effect because the account is novel in that metacognition is assumed to be a key inducing the effect.