Brain's early warning system for pain

New research showing how the brain builds an "early warning detection system" by working out the odds on potentially harmful experiences could pay dividends in the treatment of chronic pain, UK researchers report in Nature.Dr Ben Seymour and colleagues at the Wellcome Department of Imaging Neuroscience, University College London, conducted a study in fourteen men and women undergoing a half-hour test while lying in a functional magnetic resonance brain scanner. They were then shown a series of abstract pictures followed by a one-second electric shock.When the tests were completed many of the volunteers could not recall the sequence of images. But the scanner revealed that two key areas, the ventral striatum and part of the cerebral cortex, were working together to figure out what was coming next."If we showed a square followed by a circle followed by the painful shock this part of the brain could soon learn to predict that the circle was bad news," said Dr Seymour. "However, after a while, it would learn that the square wasn't that good either, as it was followed by the circle. By recording these chains of events, the brain was able to set early alarm bells ringing in the volunteer.Evolution favours animals that are good at looking after themselves, Dr. Seymour noted. "Although we may not always be aware of it, the brain tries to ensure our self-preservation through a complex mathematical strategy."He hopes that further research on the brain's computational skills could eventually help many people who suffer ongoing pain."Although chronic pain is relatively common, it remains poorly understood and often remarkably difficult to treat," he added. Reference...