Abstract
Much is known about how metacognition modulates individual performance in perceptual decision. Yet to be determined is how metacognitive ability modulates the performance of collective perceptual decision. In the first experiment (Exp 1), we adopted a contrast discrimination task and examined the relationship between collective (dyad) and individual sensitivities in 12 groups (12 groups*2 subjects/group). Individual decisions were shared after each participant made choice without consulting each other; If participants disagreed, they discussed the matter until they reached a joint decision. We found that although collective perceptual sensitivity can be generally explained by a weighted confidence sharing model (WCS) that assumes individuals communicate genuinely their level of confidence (i.e. uncertainty) and two heads are Bayes-optimally integrated (Bahrami, et al., 2010), there is evident discrepancy between WCS model prediction and empirical collective sensitivity in many groups. Aiming to test whether metacognitive ability contributed to this collective failure, eleven groups were asked to report their level of confidence via confidence rating after joined decision was made (Exp 2; 11 groups*2 subjects/group). Metacognitive ability was quantified by the interrelationship of the confidence rating and the accuracy of visual judgments using the type-II receiver operating characteristic (ROC) curve (Fleming, et al., 2010). The result showed that the discrepancy between the empirical and predicted collective sensitivity negatively correlated with group metacogntive ability (r=-.703, p=0.016); the higher the metacognitive ability, the less the discrepancy. In experiment 3, we confirmed the findings in the case of triad decision (8 groups*3 subjects/group): discrepancy between empirical performance and the WCS model prediction negatively correlated with group metacognitive ability (r=-.749, p=0.018). To conclude, our results implied that metacognitive ability of understanding and communicating visual uncertainty modulates optimization of collective perceptual decision.
Meeting abstract presented at VSS 2015