Assessing the Effects of Acupuncture by Comparing Needling the Hegu Acupoint and Needling Nearby Nonacupoints by Spectral Analysis of Microcirculatory Laser Doppler Signals

Figure 4

Changes in RECs in the LDF spectra at the three measurement sites. Stimulation and measurement sites: (a1) needling Hegu (n = 13), Site 1; (a2) needling Hegu, Site 2; (a3) needling Hegu, Site 3; (b1) control (n = 10), Site 1; (b2) control, Site 2; and (b3) control, Site 3. The REC of each frequency band was defined as the total energy density within a particular frequency band divided by the total energy density of the entire spectrum from 0.0095 to 1.6 Hz. *P < .05 and **P < .01, compared with the baseline value by two-tailed paired t-test. At Hegu in the Hegu experiment, the REC was significantly decreased at FR2 and was significantly increased at FR5 during the early effect; RECs then moved towards their baseline values during the later effect. There were no significant changes in any band at the nonacupoints in the Hegu experiment and at all three sites in the control experiment.