Acupuncture—an ancient healing practice that has shown promise in treating chronic pain—typically involves a period of active needle stimulation, followed by a longer period of rest. It appears that the analgesic (pain-relieving) effects of acupuncture may actually peak long after the active stimulation ends. In the first study of its kind, NCCAM-supported researchers from Massachusetts General Hospital, Logan College of Chiropractic, and Kyunghee University (Korea) evaluated the effects of acupuncture on brain activity following active stimulation.
The researchers used functional magnetic resonance imagery (fMRI) to monitor brain activity in 15 healthy adults before and after true acupuncture and sham acupuncture. The procedure lasted 150 seconds, and the rest period was 5.5 minutes. They also monitored heart rate and respiration and surveyed the subjects on their perception of pain and other sensations (such as deqi, unique sensations experienced in connection with acupuncture and considered to be signs of its effectiveness).
Analysis of the fMRI images showed that following true acupuncture—but not sham—there were increased connections among the parts of the brain involved in the perception and memory of pain. The subjects also reported stronger sensations with true acupuncture than with sham. The researchers conclude that acupuncture changes resting-state brain activity in ways that may account for its analgesic and other therapeutic effects.
Dhond RP, Yeh C, Park K, et al. Acupuncture modulates resting state connectivity in default and sensorimotor brain networks. Pain.; 136(3):407–418.2008