Perceptual confidence has near perfect access to the existence of discrete representations, but only weak access to precision

Perceptual confidence describes the degree to which we believe our internal perceptual representations reflect the external stimuli that caused them. How confidence is derived from internal representations is currently debated, but answering this question is made difficult because the nature of internal representations is also an ongoing debate. Here we leverage recent findings regarding how global motion is internally represented to test the prominent hypothesis that confidence is derived from internal representations. Participants estimated the global motion direction of two types of random-dot stimuli. In Experiment 1 a stimulus was used which induces discrete, all-or-none segmentation of signal and noise dots. Confidence nearly perfectly tracked whether or not these discrete representations existed, but had no relationship with their precision despite some representations being more precise than others. In Experiment 2 a motion stimulus was used which induces continuous local motion pooling characterized by large differences in response precision. Although confidence tracked the precision of these continuous representations, the relationship between confidence and precision was much weaker, suggesting that meta-knowledge of precision is highly error prone. This dissociation was also present when both discrete and continuous motion stimulus were presented intermixed in Experiment 3, suggesting that it is not merely driven by task set. Instead, the way in which confidence is derived from motion representations depends on whether they arose from a discrete or continuous encoding process. These results support theories which posit that confidence is generally derived from internal perceptual representations, but has only limited access to the precision of those representations.