Evidence accumulation relates to perceptual consciousness and monitoring
Nature Communications May 31, 2021 M. Pereira, P. Mégevand, Mi Xue Tan et al.
Conscious perception and the ability to reflect on one's own perceptual experiences both rely on a common neural mechanism of evidence accumulation in the posterior parietal cortex. Recordings from a single neuron in a human participant, combined with electroencephalography in healthy volunteers, showed that detected tactile stimuli triggered neuronal activity resembling the gradual buildup of evidence seen during decision-making. A computational model reproduced the behavioral and neural data, treating a stimulus as detected when accumulated evidence reaches a threshold, and confidence as the distance between the maximal evidence and that threshold. The findings suggest that gradual changes in neuronal dynamics during evidence accumulation underlie both perceptual consciousness and perceptual monitoring.