Acupuncture is originated from China thousands years ago and has been used since. It is now more popular than ever in all over the world. However mechanisms of acupuncture on the central nervous system (CNS) still remain unclear.
New techniques are invented to study brain including Functional Magnetic Resonance Imaging (fMRI), Positron Emission Tomography (PET), Electroencephalography (EEG), and Evoked Potentials (EP). fMRI can used to measure the brain's neuronal activity and the resulting regional changes in metabolism and circulation.PET can be used to measure the brain's regional blood flow, oxygen, or glucose metabolism and reflect the activity in the according brain region. EEG is used to measure brain activity. EP measurement reflects the number of cortical cells activated and the intensity of the stimulus. These techniques are applied to acupuncture research. Using these technologies, researchers are able to examine the acupuncture process in the brain noninvasively and provide scientific evidences how acupuncture works.
Using biochemical approach, researchers found that acupuncture analgesia might be induced by the release of endogenous opioids, as well as by modulating other signalling systems such as the adrenergic system/the serotonin signalling system/the N-methyl-D-aspartic acid/AMPA/kainate signalling system etc. Recently by using neuroimaging techniques researchers found that acupuncture modulates brain networks such as brain resting state networks; acupuncture modulates a wide network of brain areas including cortical, subcortical/limbic, and brainstem areas; acupuncture can enhance functional connectivity among different brain regions.
References
Scheffold BE et al Evid Based Complement Alternat Med (2015) 2015:641742
