Abstract
AbstractThe integration of somatosensory signals across fingers is essential for dexterous object manipulation. Previous experiments suggest that neural populations in the primary somatosensory cortex (S1) are responsible for this integration. However, the integration process has not been fully characterized, as previous studies have mainly used two-finger stimulation paradigms. Here, we addressed this gap by stimulating all 31 single- and multi-finger combinations. We measured population-wide activity patterns evoked during finger stimulation in human S1 and primary motor cortex (M1) using 7T functional magnetic resonance imaging (fMRI). Using multivariate fMRI analyses, we found clear evidence of unique non-linear interactions between fingers. In Brodmann area (BA) 3b, interactions predominantly occurred between pairs of neighboring fingers. In BA 2, however, we found equally strong interactions between spatially distant fingers, as well as interactions between finger triplets and quadruplets, suggesting the presence of rich, non-linear integration of somatosensory information across fingers.
Publisher
Cold Spring Harbor Laboratory