Figure 5. Corticomuscular coherence (CMC) obtained for right hand muscles for 5 subjects in the bimanual and unimanual conditions.

A. Grand average time-frequency plots of the z-score CMC between right hand FDI and electrodes C3 and FCz in the bimanual condition (left side) and in the unimanual condition (right side). The color scale indicates the z-score CMC values, thresholded between 0 and 2 for clarity. The vertical axis represents the frequency scale ranging from 10 to 60 Hz. The horizontal axis represents the time scale ranging from 1.5 to 13.5 s (0 s, off-scale, corresponds to the beginning of the ascending ramp). The vertical dotted lines indicate the time windows over which we averaged to obtain the topographies. B. Grand average z-score CMC topographies averaged over the frequency band 20–30 Hz and over 2 s of the periods of interest SF1.5 and SF0.5 for right hand FDI obtained for the bimanual condition (left side) and the unimanual condition (right side). The color scale indicates the z-score CMC values, thresholded between 0 and 1 for clarity. M1_R: right primary motor cortex. M1_L: left primary motor cortex. SMA: supplementary motor area. Similar results were found for right AbPB (not shown).