Exploring dynamical coupling between primary somatosensory and motor cortices
Huy Cu, Laurie Lynch, Kevin Huang, David Borton, Wilson Truccolo & Arto V. Nurmikko
Everyday experiences that are essential to intelligent dexterous manipulation for primates involve interaction between tactile sensory inputs and motor outputs in the nervous system. Still, the functional communication between sensory and motor cortical areas is underexplored. We compute the intracortical Granger Causality, which may reveal the functional connectivity, between the hand primary motor (M1) and somatosensory (S1) cortices as monkeys perform the compliant-object squeezing task with tactile surprising. (Fig. 1)
We report that the Granger Causality between M1 and S1 is bidirectional and that communication gradually changes depends on the stage of the task. Comparing to the resting stage, causalities in the steady stage are significantly stronger by numerous pairs of signals and are prominently driven by the M1. During the tactile surprise and recovering stage, we report the role of S1 in providing sensation feedback as the S1-causality increases remarkably the M1-causality becomes less significant. Finally, frequency analyses suggest that Beta (15-30hz) oscillation provides another path of temporal communication between primary motor and sensory cortices. Together, these findings suggest that sensorimotor integration could be relied on and modified through the Granger causality and Beta band dynamics.
Granger Causalities show bi-directional communication between 2 areas
Abrupt and Randomly Timed Change in Compliance Modulates Somatosensory Circuits and Affects Bidirectional S1-M1 Communication
Abrupt compliance change affects field potentials in the frequency domain