Electrophysical characterization of biologically active points and human skin by in vivo impedance measurement

The present work describes the in vivo electrical characteristics of the biologically active point (BAPs, also known as the acupuncture points) present in the human body, and compares them with those of the human skin. The impedance measurements of the BAPs and of the surrounding human skin, measured at a distance 5-10 mm from the BAP, were carried out in vivo on 36 young healthy people of 18 to 28 years of age. The results of the measurements have shown that (i) the resistance of BAP is lower and the capacitance is higher than the corresponding parameters of skin; (ii) the impedance spectra of BAP differ from the impedance spectra of skin not only quantitatively, but qualitatively: the former consist of two semicircles, whereas the latter has only one. An equivalent electrical circuit of a BAP is proposed, which agrees well with our experimental results. The data obtained show that the large dispersion of the in vivo impedance characteristics of the human body, measured in different parts of the body may be the effect of presence of the biologically active points under the area of the electrodes.