Effective connectivity predicts distributed neural coding of perceptual decision confidence, uncertainty and speed

Decision-making is often accompanied by a level of confidence regarding the accuracy of one’s decision. Previous studies have indicated neural activity associated with perceptual decision confidence during sensory stimulus presentation. Choice reaction time (RT) has been suggested as an indirect but more objective measure of decision confidence – generally faster RT for higher confidence. However, it is unclear whether choice confidence and RT have similar neural correlates. Within a perceptual decision-making task, we applied fMRI-informed EEG-based effective connectivity analysis via dynamic causal modelling (DCM) on event-related potentials and found the frontoparietal network for fast-vs-slow RT condition to be different from that of high-vs-low confidence rating condition. Furthermore, trial-by-trial DCM analysis predicted parietal cortical layer-based, distributed and nonlinear coding of RT, confidence or uncertainty, which cannot be readily captured by scalp-level EEG. Collectively, our study suggests that decision confidence and speed are instantiated by different dynamical networks distributed across cortical layers.