Harmonic effects of sham acupuncture at Tsu San Li (St-36) in the radial pulse wave

Background and aim: Acupuncture has been criticized as a theatrical placebo for the sham effect. Unfortunately, sham tests used in control groups in acupuncture studies have always ignored the underlying biophysical factors, including resonance involved in acupuncture points and meridians.Experimental procedure: In this study, the effects of sham acupuncture at Tsu San Li (St-36) were examined by analyzing noninvasive 30-sec. recordings of the radial arterial pulses for 3 groups of patients treated with different probes (blunt, sharp, and patch) on the superficial skin of the acupuncture point. The 3 groups were then treated with the sharp probe for 3 different periods (16, 30, and 50 s). Then we compared the harmonics of the radial arterial pulse after Fourier transformation before and after the treatment. Results: Our results indicated that different probes have effects similar to needle insertion at Tsu San Li. Meanwhile, the harmonic effect of the sharp probe strengthened as time increased. Conclusions: This study revealed that the meridian effect of sham testing from mechanical stimulation, even from simple touch, on an acupuncture point, should not be overlooked. Thus, even simple touch can be added to electrical or laser acupuncture.(c) 2023 Center for Food and Biomolecules, National Taiwan University. Production and hosting by Elsevier Taiwan LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).