Confidence reports during perceptual decision making dissociate from changes in subjective experience

In noisy perceptual environments, people frequently make decisions based on non-perceptual information to maximize rewards. Therefore, a central problem in psychophysics, metacognition and consciousness research is to distinguish between decisions resulting from changes in subjective experience and those arising from non-perceptual information. It has recently been proposed that confidence reports can be used to discriminate between changes in subjective experience and those arising from non-perceptual information. Here we use a Bayesian ordinal modeling framework combined with an explicit measure of subjective experience to show across two experiments and three bias manipulations that confidence during perceptual decision-making does not uniquely reflect subjective experience. Instead, non-perceptual manipulations affecting response bias ‘leak’ into perceptual confidence reports. This occurs not only for biases resulting from changes in the base-rate of stimuli (‘cognitive’ priors), but also when biasing information does not inform decision correctness (asymmetric payoff matrix).