Figure 4.
Interaction of the parietal (PCS, 80% RMT) and premotor (CS, 90% RMT) cortices on the motor cortex. Error bars signify SEM. When conditioning the PMv at 4 ms, preconditioning of the parietal cortex reversed the premotor inhibition at 10 and 15 ms. When conditioning the PMv at 6 ms, preconditioning of the parietal cortex reversed the premotor inhibition at 6, 8, and 10 ms. The peak of the PPC-PMv interaction was observed at PMv 6ms-PPC 6 ms, which is earlier than the peak facilitation ISI (8 ms) for PPC stimulation alone.