Abstract
“Reality monitoring” is the ability to judge the source of a memory, which can be either internally-generated (imagined) or externally-generated (perceived). Previous research suggests that both imagined and perceived stimuli recruit similar brain areas but show differentiable neural processing. This distinct neural processing leads to differences in experiences where perceived stimuli are relatively clear and precise, but imagined stimuli are vague and imprecise (Dijkstra, Kok & Fleming, 2022). Potentially, differences in the vividness of experience may lead to differences in metacognitive (i.e., confidence) judgments about the source of an experience. Here, we ask: if participants judge whether the source of a stimulus is imagined, perceived, or new, what is the profile of metacognition for each source type? To answer this question, we conducted an experiment where on each trial, participants saw a word, followed by either a corresponding picture or a blank screen. Participants were asked to imagine an image of the corresponding word when the screen was blank. After they saw or imagined a picture, they rated their visual experience on clarity and artistic merit. In the final block, on each trial, participants viewed a single word, which was either previously shown or brand new. On each trial, they judged that word to be previously-perceived, previously-imagined, or new, and reported their confidence in a single, simultaneous report. Results showed an omnibus effect of source on accuracy and confidence, but not on reaction time. Post-hoc comparisons revealed similar accuracy and confidence for perceived and imagined items. However, judgments for 'new' words were significantly more accurate than either of these two sources, and also exhibited significantly lower confidence. Overall, these results suggest that differences in our experiences of imagined and perceived stimuli may not necessarily be accompanied by differences in confidence judgments about the sources of these experiences.