The Function of Self Touch Body Language
When we’re hurt, we brace ourselves. For example, pinching your fingers in a door jam forces our hands together. Our healthy hand instinctively clasps the hand that is in pain. But why do we do this and what does it mean when we do this absent of any apparent physical injury?
Researchers Marjolein Kammers, Frederique de Vignemont and Patrick Haggard devised a study using the “thermal grill illusion” to show that people use self-touch to reduce acute pain.
In the study, participants pressed their fingers on two warm objects surrounding one cool object. The warm which surrounds the cool unmasks pain pathways which then make the cool object feel painfully hot. In the experiment, the researchers warmed the index and ring finger while cooled the middle finger of each (the thermal grill). Then the subject was instructed to press the three fingers of one hand against the other three fingers. Amazingly, this reduced the perception of pain by 64% suggesting that touch itself was effective at reducing perception of pain.
This experiment shows why we clutch a painful hand with the other hand.
“We show here that self-touch not only gates pain signals reaching the brain but also, via multisensory integration, increases coherence of cognitive body representations to which pain afferents project,” say the researchers.
The results indicate that self-touch is a way that we deal with physical pain. However, previous research has also noted that self-touch is also a way that people deal with emotional pain.
When we see a person self-hug, stroke, or rub themselves such as their forearm, or the back of their neck or head, we can use this as evidence that a person is dealing with negative emotions. In much the same way that self-touch helps us deal with physical pain, self-touch also helps us deal with emotional pain through tactile comfort.
Kammers, Marjolein P.M.; Frederique de Vignemont and Patrick Haggard. Cooling the Thermal Grill Illusion through Self-Touch. Current Biology. 2010. 20, 1819–1822. DOI 10.1016/j.cub.2010.08.038