Mapping digit-representations in BA3b during stimulation and investigating their intrinsic connectivity at rest using VASO

While inter-digit interactions are crucial for manual abilities like tool use or object manipulation, individual digits seem to be distinctly represented in the primary somatosensory cortex. Here, we used cortical depth-resolved high-resolution CBV-measurements to investigate these representations in the putative S1-subregion “BA3b” and depth-dependent temporal correlation during rest, as a potential index for layer-specific integration between digit representations. We found that we can

1. identify individual digit-representations in human subjects during stimulation using VASO
2. show more specific depth profiles for VASO than BOLD
3. see intrinsic interactions between digits at rest, which might be driven by deep-to-deep layer connections