Fibromyalgia Patients May Process Pain Differently

Brain scans reveal that people with fibromyalgia are not as able to prepare for pain as healthy people, and they are less likely to respond to the promise of pain relief.This altered brain processing could explain why people with the mysterious chronic ailment feel pain more intensely and don't respond as well to narcotic painkillers.the people with fibromyalgia needed much less pressure to reach the same pain rating as a healthy person,But the doctors also noticed key differences in the way certain parts of their brain dealt with pain before, during and after.One brain region that showed an altered response was the ventral tegmental area (VTA), a group of neurons in the center of the brain that responds to reward or punishment. The VTA helps regulate the release of dopamine, a pain-relieving brain chemical. It plays a crucial role in a person's response to pain medications and has been linked to drug addiction."The VTA in healthy volunteers activated before pain and during pain, and the region deactivated when they received the relief signal. People were more worried about the pain to come and more rewarded by the cue that the pain would soon end," Loggia said. "In people with fibromyalgia, we don't see this. The activation is completely blunted."The altered response of the VTA also could explain why fibromyalgia patients often do not respond to narcotic painkillers, he added.The investigators also noted a different response in the periaqueductal gray (PAG), a small structure in the center of the brain that plays a role in pain transition. "In animals, it has been shown that if you electrically stimulate this area, pain responses go down," Loggia said.The PAG activates in healthy people who have received a cue that pain is imminent, as they prepare themselves for the pain to come. But the region does not activate when people with fibromyalgia are warned of oncoming pain, suggesting that they are less capable of guarding against pain signals,Loggia noted that the altered brain activity could be explained away by the fact that fibromyalgia patients endure constant pain and the disorder has altered the brain response, instead of the other way around."The healthy volunteers go from a state of no pain to a state of pain," he said. "But fibromyalgia patients go from a lower level of pain to a higher level of pain, which could affect the way they process the pain and relief cues."