title: Changes in electrical skin resistance at gallbladder 34 (GB34).
abstract: OBJECTIVE
  Electrodermal screening is widely used in the acupuncture community for point location, diagnosis and therapy. However the underlying theory that electrical skin resistance (ESR) of an area corresponding to an acupuncture point (AP) is lower than ESR of the surrounding areas is yet to be proven. The objective of this study was to evaluate and quantify the phenomenon of ESR changes at the Gallbladder 34 (GB34) Acupuncture Point (AP).
  
  
  METHODS
  In this single-blinded study GB34 was measured bilaterally in 43 healthy volunteers. Electrical skin resistance measurements (ESRMs) were performed with a specially designed array consisting of 64 (8 x 8) electrodes on an area of 6 x 6 cm. Then the electrodes corresponding to the AP were identified and compared with those of the surrounding electrodes with Wilcoxon rank sum test. Values for p of less than 0.05 were considered statistically significant.
  
  
  RESULTS
  Eighty-one ESRMs were evaluated. ESR was significantly different from the surrounding skin area in 27 (33.3%) cases with 15 (18.5%) points showing a lower and 12 (14.1%) points showing a higher ESR.
  
  
  CONCLUSIONS
  This shows that ESR changes at APs exist in one third of the measured points, a very low rate for a postulation that forms the basis of various diagnosis and therapy systems.
authors.affiliation: Multidisciplinary Pain Centre, Department of Anesthesiology, University of Munich, Munich, Germany.
authors.forename: Sybille
authors.initials: S
authors.lastname: Kramer
authors.forename: Daniela
authors.initials: D
authors.lastname: Zaps
authors.forename: Bernhard
authors.initials: B
authors.lastname: Wiegele
authors.forename: Dominik
authors.initials: D
authors.lastname: Irnich
mesh_terms: D015669:Acupuncture Points; D015670:Acupuncture Therapy; D000293:Adolescent; D000328:Adult; D017097:Electric Impedance; D006801:Humans; D008297:Male; D012867:Skin / Q000737:chemistry*; D055815:Young Adult