Metacognition-related regions modulate the reactivity effect of confidence ratings on perceptual decision-making.

Prompting confidence ratings following perceptual decision-making could significantly affect the decision-making per se, a phenomenon known as the reactivity effect. The current study aimed to explore the neural substrates underlying the reactivity effect by comparing behavioral and functional magnetic imaging data between when participants making decisions with prompted confidence ratings (DCR+) and when without providing confidence ratings (DCR-). The results showed that DCR+ was associated with longer decision response times (RTs) and higher accuracy than DCR-. The analysis of fMRI data revealed significantly increased activation in the DCR+ condition, relative to the DCR- condition, in multiple metacognition-related regions including the left supplementary motor area, left dorsal anterior cingulate cortex, left opercular part of the inferior frontal gyrus, and bilateral precuneus. Changed beta values (BetaDCR+ minus BetaDCR-) of these clusters were correlated with the changed decision RTs between the two conditions (ΔRT = RTDCR+ - RTDCR-). Psychophysiological interaction analysis revealed increased functional connectivity between the left supplementary motor area and the right inferior parietal lobe in the DCR+ condition than the DCR- condition. Further multiple regression analysis found that ΔRTs was significantly associated with activities in the bilateral dorsal anterior cingulate cortex and supplementary motor area. Together, this study found that provide confidence ratings significantly changed online decision-making while activating multiple metacognition-related regions. The activity of metacognition-related regions may be a crucial part of the neural mechanisms underlying the reactivity effect of confidence ratings on perceptual decision-making.