Abdominal acupuncture reduces laser-evoked potentials in healthy subjects

Objective: Acupuncture is known to reduce clinical pain, although the exact mechanism is unknown. The aim of the current study was to investigate the effect of acupuncture on laser-evoked potential amplitudes and laser pain perception. Methods: In order to evaluate whether abdominal acupuncture is able to modify pain perception, 10 healthy subjects underwent a protocol in which laser-evoked potentials (LEPs) and laser pain perception were collected before the test (baseline), during abdominal acupuncture, and 15 min after needle removal. The same subjects also underwent a similar protocol in which, however, sham acupuncture without any needle penetration was used. Results: During real acupuncture, both N1 and N2/P2 amplitudes were reduced, as compared to baseline (p<0.01). The reduction lasted up to 15 min after needle removal. Furthermore, laser pain perception was reduced during real acupuncture, although the difference was marginally significant (p=0.06). Conclusions: Our results show that abdominal acupuncture reduces LEP amplitude in healthy subjects. Significance: Our results provide a theoretical background for the use of abdominal acupuncture as a therapeutic approach in the treatment of pain conditions. Future studies will have to be conducted in clinical painful syndromes, in order to confirm the analgesic effect of acupuncture in patients suffering from pain.