Experiencing misinformation: The effect of pre-exposure warnings and debunking on psychic beliefs.

Misinformation can have a detrimental impact on our beliefs, and it is therefore necessary to understand the cognitive mechanism by which false information is integrated or can be changed. In two experiments, we worked with fake psychic demonstrations, because observers easily adopt the experience as reflecting a "true" psychic event. We manipulated the availability of alternative explanations by providing a general warning that the performer is a magician with no psychic abilities (Experiment 1) or disclosing afterwards how the fake demonstration had been staged (Experiment 2). In Experiment 1, witnessing the psychic demonstration significantly increased participants' psychic beliefs, even though they had been warned. However, providing the alternative explanation about the deceptive method mitigated this effect. In Experiment 2, the realisation of deception significantly reduced participants' psychic beliefs directly after the performance and remained reduced 1 week later.

Differential Effects of Experience and Information Cues on Metacognitive Judgments About Others' Change Detection Abilities.

This study explored the interaction between visual metacognitive judgments about others and cues related to the workings of System 1 and System 2. We examined how intrinsic cues (i.e., saliency of a visual change) and experience cues (i.e., detection/blindness) affect people's predictions about others' change detection abilities. In Experiment 1, 60 participants were instructed to notice a subtle and a salient visual change in a magic trick that exploits change blindness, after which they estimated the probability that others would detect the change. In Experiment 2, 80 participants watched either the subtle or the salient version of the trick and they were asked to provide predictions for the experienced change. In Experiment 1, participants predicted that others would detect the salient change more easily than the subtle change, which was consistent with the actual detection reported in Experiment 2. In Experiment 2, participants' personal experience (i.e., whether they detected the change) biased their predictions. Moreover, there was a significant difference between their predictions and offline predictions from Experiment 1. Interestingly, change blindness led to lower predictions. These findings point to joint contributions of experience and information cues on metacognitive judgments about other people's change detection abilities.

Exploiting failures in metacognition through magic: Visual awareness as a source of visual metacognition bias.

We used cognitive illusions/magic tricks to study the role of visual awareness as a source of biases in visual metacognitive judgments. We conducted a questionnaire-based study (n = 144) and an eye tracking study (n = 69) in which participants watched videos of four different magic tricks that capitalize on failures of visual awareness (inattentional blindness and change blindness). We measured participants' susceptibility to these illusions, their beliefs about other people's susceptibility, as well as the role that fixating (i.e. eye position) the critical event has on detecting the secret. Participants who detected the method of the tricks believed it was more likely that other people would detect it compared to those participants who failed to notice the method. Moreover, they believed that they moved their eyes to look at it. Eye tracking data show that, contrary to participants' beliefs, peripheral vision played a significant role in detecting the method. Overall, the findings from these studies suggest that visual awareness may bias visual metacognitive judgments.