Pain relief by touch: a quantitative approach

Pain. 2014 Mar;155(3):635-642. doi: 10.1016/j.pain.2013.12.024. Epub 2013 Dec 18.


Pain relief by touch has been studied for decades in pain neuroscience. Human perceptual studies revealed analgesic effects of segmental tactile stimulation, as compared to extrasegmental touch. However, the spatial organisation of touch-pain interactions within a single human dermatome has not been investigated yet. In 2 experiments we tested whether, how, and where within a dermatome touch modulates the perception of laser-evoked pain. We measured pain perception using intensity ratings, qualitative descriptors, and signal detection measures of sensitivity and response bias. Touch concurrent with laser pulses produced a significant analgesia, and reduced the sensitivity in detecting the energy of laser stimulation, implying a functional loss of information within the ascending Aδ pathway. Touch also produced a bias to judge laser stimuli as less painful. This bias decreased linearly when the distance between the laser and tactile stimuli increased. Thus, our study provides evidence for a spatial organisation of intrasegmental touch-pain interactions.

Keywords: Analgesia; Pain; Relief; Signal detection theory; Space; Touch.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Female
  • Humans
  • Lasers / adverse effects
  • Male
  • Pain / diagnosis
  • Pain / physiopathology
  • Pain / prevention & control*
  • Pain Measurement / methods*
  • Pain Perception / physiology*
  • Pain Threshold / physiology
  • Physical Stimulation / adverse effects
  • Physical Stimulation / methods
  • Reaction Time / physiology
  • Therapeutic Touch / methods*
  • Touch / physiology*
  • Young Adult