Fibromylalgia is a condition which causes widespread chronic pain and an increased pain response, as well as fatigue and other symptoms. It is very hard to treat, having no widely understood cause, although it is believed to be influenced by both genetic and environmental factors. It appears to also involve abnormalities in how the central nervous system processes pain signals that would otherwise be innocuous.

Constructing pain

Pain is complicated - as well as the signals coming from the painful stimulus, how an individual experiences that pain can vary massively dependent on context and other factors, including attention. Dr Rob Gregory, under the supervision of Professor Tony Pickering and Dr Jon Brooks, used a distraction analgesia paradigm in 20 fibromyalgia patients and 20 control patients while they were in an MRI scanner to see if patients who suffer from fibromyalgia experience pain differently. Dr Gregory was funded by the Elizabeth Blackwell Institute’s Clinical Primer scheme.

Distraction analgesia

While the subjects were in the MRI machine, thermal stimuli were delivered to their forearms. The subjects were then asked to respond with a button press to a specific target letter in a stream of letters and numbers they’re presented with. Getting subjects to focus in this way has been shown to increase the threshold at which a stimulus is reported as painful - so the distraction of the task produces analgesia.

“We collected and processed data of high enough quality and quantity to test our hypothesis - that reduced off-cell activity in the brain region called the rostal ventromedial medulla correlates with reduced attentional analgesia in fibromyalgia patients,” said Dr Gregory. “Our early indications are that there may be a difference in attentional analgesic processes in people with fibromyalgia, which is in line with our initial hypothesis”.

Levelling up

Dr Gregory said, “A detailed analysis of the brain processes mediating this difference is currently underway: Professor Pickering’s team will continue second level imaging analysis. We also have a paper in draft and poster to be presented at FENS based on our findings.”