Emotions may determine why some people are more likely to suffer chronic pain than others, a study has found.
The emotional state of the brain can explain why different individuals do not respond the same way to similar injuries, say scientists.
Some recover fully while others remain in constant pain.
Brain scan studies showed for the first time how chronic pain emerges as a result of an emotional response to an injury.
The process involves interaction between two brain regions, the frontal cortex and nucleus accumbens.
Lead scientist Professor Vania Apakarian, from Northwestern University in Chicago, US, said: "The injury itself is not enough to explain the ongoing pain. It has to do with the injury combined with the state of the brain."
The more emotionally the brain reacted to the initial injury, the more likely it was that pain will persist after the injury has healed, he said.
Prof Apakarian added: "It may be that these sections of the brain are more excited to begin with in certain individuals, or there may be genetic and environmental influences that predispose these brain regions to interact at an excitable level."
The research involved 40 volunteers who had all suffered an episode of back pain lasting one to four months.
Four brain scans were carried out on each participant over the course of one year.
The results, published in the journal Nature Neuroscience, made it possible to predict with 85% accuracy which individuals would go on to develop chronic pain.
(WATCH) Pain Perception And The Human Brain...
The nucleus accumbens teaches the rest of the brain how to evaluate and react to the outside world.
Prof Apakarian said it may use the initial pain signal to teach other parts of the brain to develop chronic pain.
"Now we hope to develop new therapies for treatment based on this finding," he added.
Take a look at natural ways to beat pain...
8 Foods That Fight Pain
Turmeric For Muscle Pain
According to previous research, turmeric is more effective in tackling pain relief and inflammation than steroid medications. According to researchers from the<a href="http://www.nih.gov/" target="_hplink"> National Institutes of Health</a>, the pain relief properties from turmeric are more prevalent to <a href="http://www.nhs.uk/conditions/Rheumatoid-arthritis/Pages/Introduction.aspx" target="_hplink">rheumatoid arthritis</a> sufferers, as it inhibits the destruction of joints from arthritis. Turmeric contains a protein called NF-kB, which, when turned on, activates the body's inflammatory response, which helps battles aches and pains.
Red Grapes For Back Pain
Red grapes are packed full of resveratrol, a powerful antioxidant compound that blocks enzymes that degenerate tissue damage, which can lead to joint and muscle pain. According to the <a href="http://www.rush.edu/" target="_hplink">Rush University Medical Center</a>, resveratrol helps protect against cartilage damage that causes back pain in particular. Another study by the <a href="http://www.msu.edu/" target="_hplink">Michigan State University</a> found that cherry extract is ten times more effective than aspirin when it comes to relieving inflammation in the body. Other berries rich in back-pain fighting resveratrol include blueberries, cranberries and blackberries.
Ginger For Knee Pain
Ginger is well known for its ability to block the pain-causing prostaglandin levels in the body. Ginger has long been used as a natural method of pain relief, particularly in India, where researchers regularly test its inflammation and pain relief properties. According to research by the <a href="http://www.miami.edu/" target="_hplink">University of Miami</a>, researchers discovered that two third of patients with chronic knee pain reported less soreness after taking a daily dose of ginger extract for six weeks. Health experts recommend a daily dosage of 500 to 1,000mg of ginger a day to help ward off aches and pains.
Soy For Joint Pain
Research by the <a href="http://osu.okstate.edu/welcome/" target="_hplink">Oklahoma State University</a> found that osteoarthritis sufferers who consumed 40g of soy protein a day for three months, reported a 30% improvement on their arthritis-related knee pain. Soy contains bundles of <a href="http://www.isoflavones.info/" target="_hplink">isoflavones</a>, a plant hormone with strong anti-inflammatory properties, which helps reduce the discomfort of osteoarthritis and other related joint pains.
Salmon For Neck Pain
Omega-3 fatty acids are crucial for keeping the immune system healthy - and warding off inflammation and chronic neck pain. During research at the <a href="http://www.pitt.edu/" target="_hplink">University of Pittsburgh</a>, 60% of participants experienced enhanced pain relief from eating more fish or taking fish oil supplements for three months. The effect was so great, almost as many stopped taking their daily pain relief as a result. Besides salmon, other fish that contain high levels of the essential EPA and DHA omega-3 fatty acids include halibut, tuna, trout, mackerel and sardines.
Cherries For Arthritis
Cherries, like the other members of the berry family, contain high amounts of antioxidants called anthocyanins - the key compound to the cherry's pain fighting power. According to research by the <a href="http://www.agriculture.gov.ie/" target="_hplink">Department of Agriculture</a>, participants who ate 45 big cherries daily for 28 days reduced their inflammation levels significantly. Researchers found that cherry anthocyanins are especially effective in treating arthritis symptoms, as participants of the study said their joint pain had improved as a result of consuming cherries or cherry juice. Anthocyanins contain antioxidants, anti-inflammatory and anti-diabetic properties.
Coffee For Post-Workout Pain
If you ever wondered why over-the-counter painkillers contain caffeine, it's because coffee enhances the effects of common pain relief. It also acts as a natural pain reliever itself, particularly good for post-workout aches and pains. Researchers from the <a href="http://www.uga.edu/" target="_hplink">University of Georgia</a> discovered that patients who drank two cups of coffee after working out, reduced common post-workout aches and pains by almost 50%. Experts also claim that caffeine is good for a pre-workout boost too, as it has been proven to raise the body's pain threshold.
Sage For Sore Throats
The humble sage is commonly used to treat throat ailments, like tonsillitis, mouth ulcers, gum disease, laryngitis, as well as other problems like headaches, bruises, bad memory and common menopause symptoms. Sage contains rosmarinic acid, which is absorbed into the body and acts as an anti-inflammatory agent, which soothes inflamed muscles. Add it to boiling water and make your own sage tea, or sprinkle it as a seasoning on your food.