Why do we touch the painful area after receiving a blow? A new study by neuroscientists at University College London (UCL) shows thatplacing our hands on the affected area relieves pain.
To demonstrate this, researchers Patrick Haggard, Marjolein Kammers and their colleagues worked with a group of volunteers who caused them to feel pain using an experimental model called“thermal grill illusion”(TGI), in which they were asked to put their index and ring fingers in hot water and their heart in cold water. This generates aparadoxical painful sensation of heat in the middle finger, which allows scientists to investigate the experience of pain without causing harm to anyone.
The most interesting thing is that, if the three fingers were then touched with the same fingers of the other hand, thepain experienced was reduced by up to 64%. However, when another person pressed the affected hand, no relief was experienced.
According to the researchers in the journalCurrent Biology,? acute pain levels depend not only on the signals sent to the brain, but also on how the brain integrates these signals into acoherent representation of the body as a whole“And that is achieved by touching the painful area yourself.
The researchers now hope to apply their new knowledge to also understand the brain mechanisms involved in chronic pain and to find our analgesic strategies that reduce the perception of pain.
