Researchers in this small study used a special brain scan called a blood oxygenation level-dependent (BOLD) contrast fMRI to look for different reactions to pain in fibromyalgia and healthy controls in response to varying amounts of pressure.
They say scans revealed significant activity differences in the insular cortex (IC) and superior temporal gyrus (STG) at medium and high pressure levels. Furthermore, at medium pressure levels the amount of change in the STG was greater for those with more tender points.
The Insular Cortex
The insular cortex, also called the insula, deals with myriad functions, including:
- Judging the degree of pain
- Blood pressure regulation, especially during exertion
- Judging temperature level
- Body awareness
- Eye movement
- Gastric motility
- Use of complex language
Previous research has linked fibromyalgia to high levels of the neurotransmitter glutamate in this region. Glutamate is an excitotoxin, which means it stimulates activity -- and sometimes a dangerous level of over-activity -- in brain cells.
The Superior Temporal Gyrus
The superior temporal gyrus deals with many functions as well, including:
- Sound processing, including frequency and amplitude
- Language comprehension
- Language production, including word generation and object naming
- Social cognition (interpreting and reacting to social cues)
Previous fibromyalgia research has identified a decreased grey matter in this region, suggesting altered function. STG abnormalities may also be associated with language and social impairment in autism.
Abnormal activity in the IC and the STG could help explain many symptoms of fibromyalgia. This research also supports the prevailing theory that fibromyalgia is a neurological illness.
Learn more or join the conversation!
- Fibromyalgia Pain: Physiological Evidence
- Fibromyalgia & Language Problems
- Temperature Sensitivity in Fibromyalgia
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