[Progress of fMRI Research on "Deqi" of Acupuncture and Our Considerations About Further Studies].

The objectification of "Deqi" of acupuncture is a hot topic in acupuncture research at present, and functional magnetic resonance imaging (fMRI) is one of the most frequently-used techniques for revealing its brain responses. We searched literature about "Deqi" from PubMed in recent 10 years by using key words "Deqi""acupuncture sensation""needling sensation" and fMRI, trying to expound the central mechanism of "Deqi" and to put forward our understandings. Acupuncture "Deqi" evoked deactivation of the limbic-paralimbic-neocortical network (LPNN)/ default mode network (DMN), including medial prefrontal cortex (frontal pole, anterior cingulate), temporal lobe (amygdala, hippocampus, parahippocampus gyrus, temporal pole), and apparent activation of brain regions as the somatosensory cortex, thalamic-somatosensory area-insular lobe, orbitofrontal cortex, etc., which may enhance the connectivity of brain networks and function in analgesia, anti-anxiety, anti-depression, etc., but the activated and deactivated brain regions are different from study to study possibly due to the stimulated different acupoints, subjects' psychophysical conditions, scanning parameters, image acquiring sequences, etc. It is recommended that the coming stu-dies should pay more attention to the influence of acupuncture "Deqi" on brain functions in subjects suffering from diseases, the brain response characteristics of the longer post-effects and the accumulated effects of acupuncture treatment.