A characteristic estimation of bio-signals for electro-acupuncture stimulations in human subjects

This research evaluates the effect of physiological responses during electrical acupuncture (EA) stimulation on specific acupuncture points (APs: PC5 and PC6). A variety of special responses in the human body were determined by electroencephalogram (EEG), heart rate (HR) in an electrocardiogram (ECG), and skin impedance test for 2 groups, sham group as a control and a group under acupuncture stimulation. The total stimulation time in this study was set for 5 min since the effect of EA on all recorded parameters became stable within this period. According to the experiments, during EA stimulation of PC5 and PC6, the power spectrum of EEG showed that the number of low frequency waves was increased in all lobes. Heart rate variability measures of 10 subjects stimulation trials at PC6 and PC5 were compared to 10 subjects who received no stimulation treatment. In both the AP and the sham groups, the mean R-R interval increased significantly during EA stimulation. A comparison between the AP and non-AP group in terms of skin resistance measurement experiments revealed no difference in skin resistance. The results of this study verified that EA stimulation of APs (PC5, PC6) causes EEG changes, and ECG heart rate changes. However, from human skin impedance measurements, the beneficial effects were not sustained. These results may be helpful in the understanding of the mechanism underlying the effect of electrical acupuncture on PC6 and PC5.