A basic study about multi channel measurement of skin impedance vector loci on the acupuncture points

Acupuncture points have been found to be points of low electrical resistance compared to the surrounding tissue. The significance and detail of the singular electrical properties of acupuncture points are uncertain at present. In this report, we measured the absolute value and the phase of skin impedance on an acupuncture point and non-acupuncture point at many frequencies and current values. Absolute value, phase and vector loci of skin impedance showed dependencies on the amplitude of applied current. So, we examined how the current dependencies changed according to the test subject and measuring points. As a result, by performing reliable measurement of skin impedance vector loci, we found that the suitable frequency range of applied current to the skin is from 10 to 400 Hz and we need to determine the current value for each measurement. Additionally, we applied those results to 4 channel measurements of the skin impedance vector loci around the acupuncture point under the condition that the room temperature and humidity were kept constant.