[Failure of acupuncture anesthesia. A psychophysical study (author's transl)].

Four volunteers judged eight levels of thermal stimuli induced by a Hardy dolorimeter, varying in intensity from extremely painful to a low level seldom even perceived. Half of the 406 stimuli were applied during acupuncture and half either before the insertion or after removal of the needles. The experimental design minimized or eliminated factors other than the needles themselves; i.e. no medications were given; the subjects were scientists accustomed to objectivity and, on a preceeding day or days, all became experienced in assigning a number (individually chosen) to the sensation produced by the different stimuli. Galvanic skin resistance was also tested. The results did not show any influence of acupuncture on pain perception or galvanic skin resistance.