Effects of acupuncture needling with specific sensation on cerebral hemodynamics and autonomic nervous activity in humans

Effective therapeutic factors in acupuncture therapy include specific stimulation points, called acupoints, and specific sensations, called de-qi, that are induced by needling manipulation. Human neuroimaging studies have reported that acupuncture stimulation with de-qi sensations induced specific activity patterns in the brain and modulated autonomic nervous activity. However, acupoints and nonacupoints have been reported to induce de-qi sensations. Thus, it remains unclear whether these physiological responses induced by acupuncture and associated with therapeutic efficacy are related to specific stimulation sites (acupoints) or unique de-qi sensations. This review focuses on the cerebral hemodynamic responses and autonomic nervous activity changes induced by acupuncture stimulation at acupoints and nonacupoints with and without de-qi sensations. We argue that the specific sensations induced by acupuncture are more important than the specific stimulation sites for inducing cerebral hemodynamic and autonomic responses and that autonomic responses during acupuncture, which might be important for therapeutic efficacy, might be mediated though the brain activity changes exemplified by the cerebral hemodynamic responses during acupuncture.