title: A novel method of eliciting pain-related potentials by transcutaneous electrical stimulation.
abstract: BACKGROUND
  Electrophysiological techniques such as laser and contact heat evoked pain-related potentials are very useful for studying trigeminal and somatic pain transmission in humans. These methods are, however, partly invasive, expensive, and therefore not available for broad clinical use. We recently proposed a novel technique of noninvasive transcutaneous electrical stimulation.
  
  
  OBJECTIVE
  To elicit pain-related evoked potentials (PREP) by using a concentric planar electrode and demonstrate their nociceptive specificity.
  
  
  METHODS
  We registered PREP following stimulation of the forehead and hand in 14 healthy volunteers. Latencies, peak-to-peak amplitudes, and conduction velocities of nociceptive fibers have been estimated. Effects of temporal and spatial summation and of cutaneous anesthesia were evaluated.
  
  
  RESULTS
  Stimulation with the concentric planar electrode produced pinprick-like painful sensation. Cutaneous anesthesia led to abolishment of PREP responses. Estimated mean conduction velocity was 11.61 +/- 5.12 m/s, which corresponded well with conduction via A-delta fibers. Spatial as well as temporal summation resulted in a parallel increase of perceived pain intensity and PREP amplitudes.
  
  
  CONCLUSIONS
  The technique is noninvasive, affordable, and easy to perform and allows quantitative assessment of human nociceptive pathways.
authors.affiliation: University of Essen, Department of Neurology, Germany.
authors.forename: Zaza
authors.initials: Z
authors.lastname: Katsarava
authors.forename: Ilya
authors.initials: I
authors.lastname: Ayzenberg
authors.forename: Florian
authors.initials: F
authors.lastname: Sack
authors.forename: Volker
authors.initials: V
authors.lastname: Limmroth
authors.forename: Hans-Christoph
authors.initials: HC
authors.lastname: Diener
authors.forename: Holger
authors.initials: H
authors.lastname: Kaube
mesh_terms: D000328:Adult; D000772:Anesthesia, Local; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D009431:Neural Conduction / Q000502:physiology; D009475:Neurons, Afferent / Q000502:physiology; D009619:Nociceptors / Q000502:physiology; D010146:Pain / Q000503:physiopathology*; D010147:Pain Measurement; D004561:Transcutaneous Electric Nerve Stimulation