Fig. 1.

Sequential cutaneous silent period (CSP) responses recorded from the voluntarily contracting abductor pollicis brevis (APB) muscle following high-intensity digital electrical stimulation. In this case, single shocks (0.2 ms square waves) were delivered to middle fingertip. The CSP was defined as the portion of tracing with no visible EMG activity. CSP onset and endpoint for each tracing was marked (vertical latency markers) and latencies were measured. The CSP duration was calculated as the difference between endpoint and onset latencies. Mean values for each digit were used for analysis. Calibration bar: 20 ms, 1 mV