Positive thinking can lower the body's sensitivity to pain, research has shown.
A five-minute session of cognitive behaviour therapy (CBT) reduced the physical pain symptoms of volunteers who had burning heat applied to their arms by almost 40%.
The finding suggests that CBT could be a useful treatment for people suffering from chronic back problems or conditions such as fibromyalgia, which causes widespread pain.
A total of 34 men and women aged 21 to 38 took part in the "mind over body" study. In a series of hour-long sessions, a thermal probe was used to apply heat to their forearms and evoke pain.
The stimulation generated secondary hyperalgesia, or enhanced pain sensitivity beyond the site of an injury - a common feature of burns.
Lead researcher Dr Tim Salomons, from the University of Reading, said: "Of the 34 participants given secondary hyperalgesia, half were trained to control negative thoughts related to the pain, the other half was given training unrelated to the pain stimuli.
"We then examined the groups' secondary hyperalgesia. The results were striking. The 'pain-trained' group achieved a 38% reduction in secondary hyperalgesia, while the control group reported an increase of 8%.
"We know that pain feels more debilitating when it signals illness or injury compared to when we are undertaking an activity we feel is beneficial - we go through the pain barrier. However we didn't know whether our beliefs simply changed the emotional response to pain or if the mind actually changed sensations that arise from the body - until now."
The CBT-trained group also reduced the self-reported "unpleasantness" of the eight pain sessions by 58%, said Dr Salomons. This indicated that CBT changed the emotional response to pain as well as the sensitivity of skin around the burn.
Each year more than five million people in the UK develop chronic pain. Back pain alone is believed to cost British business 4.9 million work days a year as a result of employee absenteeism.
The kind of CBT used, designed to alter "distorted and unhelpful" pain-related thoughts, was adapted "almost entirely" from a commonly available manual, said Dr Salomons.
"At-home cognitive treatments, working in tandem with other treatments, could make a difference to NHS finances and waiting times as well as improving the lives of chronic pain sufferers," he added.
He conducted the research, published in the journal Pain, while working at the University of Toronto in Canada.