Fig. 7

Intramuscular EMG recordings during EES and possible spillover of the EMG signal into the ECAP component in ESR trace. A EMG traces recorded by bipolar recording electrodes inserted in or near the muscle group. B Dose-response curves of the EMG recordings from bipolar electrodes. Boxes indicate stimulation current at threshold for each muscle activation, among which activation for GL, Q and BF muscles were not observed. The EMG dose-response curves were calculated using the EMG window from 1.8 to 13 ms and the magnitude is displayed in log scale. C Representative ESR traces with clear contamination to ECAP component from EMG component spillover. ECAP component versus EMG component spillover in ESR can be differentiated as the ECAP has a known conduction velocity that results in a signal propagation delay across recording contacts. Insertion on the right showing signal propagation delay in ECAP component but not EMG component. Each recording trace corresponds to a median waveform of 300 trials and a stimulation amplitude of 4 mA