What was once used to absolve you of lying, has now been proven by scientists to relieve pain. Crossing your fingers can change what you feel on a single finger, finds a new University College London research. The research, published in Current Biology, used a variation on an established pain experiment, known as the “thermal grill illusion.” In the thermal grill illusion, a pattern of warm-cold-warm temperatures applied to the index, middle and ring finger respectively causes a paradoxical, sometimes painful, sensation of burning heat on the middle finger — even though this finger is actually presented with a cold stimulus.
The thermal grill produces burning heat sensations because of a three-way interaction between the nerve pathways that tell the brain about warmth, cold and pain. The warm temperature on the ring and index fingers blocks the brain activity that would normally be driven by the cold temperature on the middle finger. Cold normally inhibits pain, so inhibiting the input from the cold stimulus produces an increase in pain signals. It’s like two minuses making a plus.
Many people suffer from chronic pain, and the level of pain experienced can be higher than would be expected from actual tissue damage. This research it raises the interesting possibility that pain levels could be manipulated by applying additional stimuli, and by moving one part of the body relative to others. This has earlier been done in yoga asanas where pressing on certain fingers relieves pain in that part of the body. It is also the underlying philosophy behind acupressure. Seems like doctors will believe yoga and acupressure are effective, now that it has been proven in a lab.