Evoked S1 responses to Electroacupuncture (EA) and Acupressure (AP): (a) For all subjects, the primary sources localized to the contralateral SI for EA (white dots) and AP (blue dots). Sources are shown as closest points on the cortex reconstructed from subjects' individual MRIs and morphed to an average inflated brain surface (sulci/gyri are dark/light gray respectively). (b) Average time-courses for all trials of EA and AP (black, dashed lines) demonstrated analogous M20, M30, M50/M60 and M120 (those of AP being slightly delayed). Five minute sub-averages (blue, red and green lines) show attenuation of peak-to-peak amplitude over the course of the run. (c) Peaks demonstrating significant decreases (p < 0.01) following 5 minutes of stimulation are marked by a red "*" For EA this was the M30 peaks and for AP the 130 ms peak. Significant differences occurring after > 10 minutes stimulation were seen for the M30 and M50 with EA and with the M50 and M120 with AP.
Witzel et al. BMC Neuroscience 2011 12:73 doi:10.1186/1471-2202-12-73