Acupuncture, a traditional therapy originated from China, has been gradually accepted as an alternative and complementary therapy by the Western medical community for its undeniable efficacy for pain and chronic diseases [1–5]. As acupuncture is widely used all over the world, its underlying mechanism attracts increasing attention. Since the 1970s, several studies of acupuncture on experimental animals have proven that the integration of central nervous system (CNS) plays an important role in acupuncture efficacy [6, 7]. With the development of neuroimaging techniques such as functional Magnetic Resonance Imaging (fMRI), Positron Emission Tomography (PET), Single-Photon Emission Computed Tomography (SPECT), electroencephalography (EEG), and magnetoencephalography (MEG), using these techniques to investigate the cerebral responses to acupuncture stimulations in vivo [8] has gradually become a spotlight in acupuncture mechanism research. Over the past two decades, there are around 200 original articles having been published in English, and a growing body of evidence demonstrates the involvement of CNS in acupuncture mechanism [9]. However, it was found that the results of acupuncture-neuroimaging studies were untenable. For example, some studies on acupoint specificity showed that the cerebral responses to acupoint stimulation significantly differed from acupoint to sham acupoint [10–13]. Some studies demonstrated that there was no significant difference in cerebral reaction between acupoint and sham acupoint [14–16]. Some investigators held that the significant difference in cerebral responses between acupoint and sham acupoint was only found during Deqi (needle sensation) state [17]. Methodology issues might contribute to the conflict results.