Pleasure and pain brain signals disrupted in people with fibromyalgia

 A disruption of brain signals for reward and punishment contributes to increased pain sensitivity (hyperalgesia) in people with fibromyalgia, says research published in Arthritis & Rheumatism. And this altered brain processing could contribute to widespread pain and lack of response to opioid therapy.

The research team enrolled 31 people with fibromyalgia and 14 healthy volunteers; functional magnetic resonance imaging (MRI) and cuff pressure pain stimuli on the leg were performed on all participants. During the MRI, participants received visual cues alerting them of impending pain onset (pain anticipation) and pain offset (relief anticipation).

During pain anticipation and relief, people with fibromyalgia had a less robust response in the areas of the brain involved in sensory, affective, cognitive and pain regulating processes.

In healthy people, the parts of the brain involved in the processing of reward and punishment were activated during pain anticipation and stimulation and deactivated during anticipation of relief. But in people with fibromyalgia, these responses were inhibited.

“Our findings suggest that fibromyalgia patients exhibit altered brain responses to punishing and rewarding events, such as expectancy of pain and relief of pain,” says Dr Marco Loggia who led the work. “These observations may contribute to explain the heightened sensitivity to pain, as well as the lack of effectiveness of pain medications such as opioids, observed in these patients.”