Abstract
Most theories of human consciousness substantially vary in the proposed spatial extent of brain activity associated with conscious perception. Here, we investigate which local and global changes accompany conscious tactile perception. Thirty-eight healthy participants performed a tactile detection task and reported their decision confidence during fMRI. We report BOLD activations and applied graph theory to analyze the whole-brain network topologies. With confident conscious tactile perception in contrast to undetected near-threshold trials, we observed increased BOLD activity in the precuneus, the posterior cingulate cortex, the intraparietal sulcus, the insula, and the contralateral secondary somatosensory cortex. For confident misses compared to correct rejections, bilateral secondary somatosensory cortices showed greater activations. Furthermore, we assessed the whole-brain functional network topology for hits, misses and correct rejections. We did not observe any significant differences in the modularity, participation, clustering or path length of the whole-brain networks, which was supported by Bayes factor statistics. While the functional network topology did not change, conscious tactile perception emerged from greater activations at task-relevant network nodes in the posterior parietal, somatosensory and insular cortices.