Fig. 3.
Block threshold trial for a bipolar electrode with contact separation of 1.0 mm. Supramaximal twitches are delivered at ~1 Hz through the proximal electrode as designated by the black arrows. As indicated by the grey bar, the HFAC is turned on at approximately 6.5 s with an amplitude of 9.0 mA and is decremented in 0.1 mA steps until conduction block is no longer complete. The circle designates the first twitch conducted by a partially conducting nerve. Full conduction is restored by the following proximal stimulation pulse.