When we accidentally touch a hot pot, we feel pain. But if we touch it as a bandage we hear more pain, because our brain is not prepared for the burning sensation and reacts by amplifying the pain “for safety”: this Curious Mental Defense mechanism It was explained in a study by the Danish University of Aarhus, who conducted an experiment on 300 participants to test their different pain reactions. “Our research shows that even when nothing dangerous happens to us, not knowing what to expect the level of perceived pain increases,” explains Francesca Fardo, one of the authors of the research published on Science Advances.
Illusion of the thermal grid. To reach their conclusions, scholars conducted an experiment in which the participants had to predict if they would receive a feeling of cold or heat on the arm. Sometimes, however, they were exposed to hot and cold stimuli simultaneously: The inability to correctly anticipate the temperature to which they were exposed caused participants a feeling of burning pain – a curious phenomenon known as “illusion of the thermal grid” -, despite the actual temperature was not harmful to the skin.
Prepare for the worst. Cerebral imaging, combined with computer modeling, has allowed the authors to see how uncertain responses are connected to specific regions of our brain. Previous studies had shown that expecting to feel better reduces the pain (placebo effect), while expecting to suffer the worsens (walnut effect): «The results of our study add a new nuance: When the brain does not know what to expect cautious, and intensifies pain beyond the necessary».
Better to know! In the short term what has been discovered, health personnel could help to develop better strategies of the pain management. For example it could be a good idea clear the patient clearly about what to expect from a therapy, rather than leaving it in uncertainty: in this way he can feel more confident than he will face, and the brain will not have to implement “Defense strategies” who would do nothing but worsen the feeling of pain.
