Conscious tactile perception entails distinct neural dynamics within somatosensory areas.
Current biology : CB – June 09, 2025
Source: PubMed
Summary
Our sense of touch relies on complex brain activity patterns. Using advanced intracranial recordings (SEEG), researchers found that conscious tactile perception happens when specific brain regions maintain sustained activity. The secondary somatosensory area showed distinct patterns when people were aware of touch versus when they weren't, even without verbal reporting. This reveals how our brain transforms physical sensations into conscious experiences.
Abstract
Distilling the neural correlates of consciousness (NCCs) in humans is challenging due to limitations in the spatiotemporal resolution of recording techniques and confounds related to pre- and post-perceptual processes. In this study, we leveraged the detailed insights provided by human intracortical recordings to elucidate how somatosensory responses to simple tactile stimuli vary across different stimulus intensities and reporting conditions. Among the various spatiotemporal components of somatosensory processing, we observed tonic responses in posterior perisylvian regions that exhibited all the key characteristics of somatosensory NCCs. These responses remained invariant regardless of reporting, displayed an all-or-nothing pattern at the verge of the sensory threshold, and showed the most pronounced divergence between perceived and non-perceived stimuli. Overall, our findings indicate that conscious perception of simple tactile stimuli depends on higher-order somatosensory regions and that sustained neural dynamics in these areas may serve as an organizational principle of somatosensory awareness.