Scientists from Denmark have found that the uncertainty of expectations can increase the perception of pain, even if there is no real threat. The work was published in the magazine of Science Advances (SA).
Usually, if we touch something familiar, such as a hot pan, our brain already knows what is expected and preparing for possible pain. But if a person is in an indefinite state, for example, the eyes tied, the pain is more intense, even if the heat source is not so hot to cause damage.
During the experiment, participants must guess whether they will feel warmth or cold on their forearm. However, in some cases, they were given both hot, and cold stimulus, causing a burning effect.
"Former research has shown that our expectations are creating our perception of pain. In this study, we wanted to understand whether the uncertainty of these expectations could also increase the pain. The burning illusion allowed us to prove that even in the absence of a real threat, the uncertainty makes the brain more severe pain, "said Francesca Fardo, Associate Professor at the University of Aarhus.
300 people took part in the study. Scientists have used computer modeling and brain imaging techniques to find out how the brain responds to uncertainty. The results showed that in the absence of clear signals, the brain prone to "safe play" and perceived pain more sharply than necessary.
"The relief expectation reduces pain, while the expectation of damage increases it. We have shown that even the lack of clarity for predictions makes the brain more intense to respond more intensively, "said Fardo.
Findings can change the approaches to the treatment of pain. Clear information about the upcoming procedures and reduced uncertainty will help patients understand the pain less.
"In the short term, these revelations will help us to better understand the mechanisms of pain perception and customize the treatment strategies. "In the future, we plan to study the influence of psychological factors, such as anxiety and depression, on the perception of pain in patients with chronic diseases," Fardo concluded.
Translation of: Manuel Tamazyan
