The effects of acupuncture needling on the evoked responses of brain, spinal cord and muscle in man.
The effects of acupuncture (needling at the Stomach Meridian-36) on the somatosensory evoked responses from the brain (SER), from the spinalcord (EESG) and on the evoked electromy o-gram (EEMG) were studied in normal healthy man. Although amplitude of the early component of the SER was variable during the course of acupuncture and among the subjects, the inhibition of amplitude was seen during and after acupuncture needling. Late components of SER and the negative and positive waves of the EESG showed a high variability during the course of needling and among the subjects. The H-wave amplitude and H/M ratio were also variable, but decreased during and after the needling. The M-wave showed no significant changes. These results suggest that acupuncture reduced the excitability of the specific sensory pathway.