Somatosensory evoked potential elicited by acupoint's stimulus.

Based on the observation that repeated acupoint stimulation elicits evoked potentials whose latency varies as a result of the stimulus intensity we assessed the evoked potential elicited by stimulus of three acupoints (Hegu, Shenmen and Houxi), comparing the results to the potentials produced by median nerve stimulus and nonacupunctural point. Fourteen healthy individuals were studied, and no modifications related to the Hegu and Shenmen point potentials increased with the amount of stimuli, until it reached a plateau at around 400 stimuli. It did not vary for Houxi and the nonacupunctural point. We conclude that the somesthesic afference from acupunctural points must involve control circuits that are quantitatively different for each point.