Chronic pain lasting longer than three months is a common problem that affects about 1 in 5 people at some point in their lives. The lack of effective treatments has led to widespread use of a group of drugs called opioids – the best-known example is morphine. Unfortunately, long-term use of opioids can cause many undesirable effects, including drug dependency.
A better understanding of how the brain’s natural painkilling system works could help scientists develop painkillers that offer relief without the harmful side effects of opioids.
Now, Zhang et al. show that the brain (imaged trough fMRI) reduces pain while individuals are trying to find relief.
A next step will be to see how the brain decides to turn off pain and if it also controls opioid-like or other chemicals. This could improve the use of opioids, or even help to discover alternative treatments for chronic pain.