Mapping a Pain Signature for Fibromyalgia
In the mapping study, Dr. Wagner and his team assessed 37 female patients diagnosed with fibromyalgia and matched them to 35 healthy controls.
The researchers conducted a series of multisensory tests on participants to assess their sensory and motor responses. For instance, by using pressure stimulation tests, they examined how patients reacted to low and high forms of pressure pain.
The purpose of the study was to analyze how the brains of FM patients responded to different forms of stimuli, particularly pain. Using the neurologic pain signature (NPS),5 a brain pattern measured by functional magnetic resonance imaging (fMRI) was used to assess pain responses in humans.
Many regions referred to in the NPS are involved in nociceptive processing, such as the thalamus, which relays sensory and motor information to the cerebral cortex.
Other regions included in the NPS:
- Secondary somatosensory regions (SI/SII)
- Posterior, mid, and anterior insula
- Adjacent opercula
- Dorsal anterior cingulate cortex
- Inferior frontal gyrus and amygdala
Hypersensitivity Detected in People With Fibromyalgia
The researcher team found that when FM patients were given a low-pressure form of pain stimulation, they reported much higher pain intensity in comparison to the control group, with a mean level of 71.71 ± 14.47 on the numerical rating scale versus 48.48 ± 18.31, respectively (between-group effect: t=5.95; P < 0.0005).4