Since the introduction of Electroacupuncture (EA), Functional Magnetic Resonance Imaging (fMRI) studies, which measures the small changes in blood flow that occur with brain activity, have found that pain managment effects of EA are greater and more effective than manual manipulation alone and that manual acupuncture and EA appear to stimulate different Central Nervous System (CNS) areas. An fMRI study of normal adults found that stimulation with EA produced fMRI signal increases in different areas of the brain than manual needle manipulation of the same point. EA also increases the tissue content of endorphins.
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