Schematic representation of the experimental paradigm used to obtain V/F waves. A) Eight to nine supramaximal stimuli (with at least 1 minute between consecutive stimuli) were delivered to the posterior tibial nerve in order to obtain V/F responses that represent the “control” condition (Fc). B-E) A single supramaximal stimulation was delivered at latencies 4 (B, VF1), 8 (C, VF2), 12 (D, VF2′) and 16 (E, VF1′) seconds after the beginning of the vibratory stimulation. An independent stimulation trial was performed for each V/F-wave, so that 8–9 stimulation trials were performed for each latency in order to obtain the desired number of V/F responses. For all cases, at least one resting minute was allowed between consecutive trials. F) Eight to nine supramaximal stimuli (with at least 1 minute between consecutive stimuli) were delivered to the posterior tibial nerve immediately after the entire vibratory stimulation duration (20 s), yielding V/F responses (in the text referred to as VFc’).