People with fibromyalgia have an increased frequency of their rhythmic brain waves in areas linked to pain modulation, which correlate with pain severity. The study, published in the journal Frontiers in Human Neuroscience, adds to the evidence of abnormal brain processing of sensory signals in fibromyalgia, indicating that interventions that regulate the rhythmicity of these neural signals might ease pain in fibromyalgia patients.
Recent research has suggested disrupted rhythms exist in neural networks connecting the thalamus — a brain region processing pain and sensory signals — and the cortex, the receiver of those signals. Such rhythmic patterns, called neural oscillations and classified according to their frequency, are crucial for numerous brain functions, and disturbed rhythm has been described also in other disease states.
The study, performed by researchers at the Seoul National University College of Medicine, South Korea, analyzed brain waves in 18 women with fibromyalgia and 18 healthy controls of the same age and sex, using recordings of spontaneous activity by magnetoencephalography.
Analysis found that patients had increased power, or amplitude, of three types of oscillations, termed theta, beta and gamma, and a slowing of a fourth, known as the alpha peak. Combining the analysis with magnetic resonance imaging, the study, “Increased Low- and High-Frequency Oscillatory Activity in the Prefrontal Cortex of Fibromyalgia Patients,” could localize the disturbances to specific brain regions.
Also, the increased activity of high-frequency beta and gamma oscillations in two brain areas — the dorsolateral prefrontal cortex and the orbitofrontal cortex — was tied to higher clinical pain scores in fibromyalgia patients. These brain regions are employed in cognitive and emotional processing of pain, and abnormal activity in these regions may explain the unrelenting perception of pain in people with the disease.
This is the first study of neural oscillations in fibromyalgia patients, presenting data that support other types of observations stating that thalamocortical dysrhythmia lies at the heart of many chronic pain disorders. While the authors stated that the findings need to be replicated in larger studies better modeling activity to specific brain regions, the study is an important contribution to the understanding of fibromyalgia disease processes.