Decreased Connectivity and Increased Blood Oxygenation Level Dependent Complexity in the Default Mode Network in Individuals with Chronic Fatigue Syndrome. — CFSMEATLAS
Decreased Connectivity and Increased Blood Oxygenation Level Dependent Complexity in the Default Mode Network in Individuals with Chronic Fatigue Syndrome.
Shan, Zack Y, Finegan, Kevin, Bhuta, Sandeep et al. · Brain connectivity · 2018 · DOI
Quick Summary
This study used brain imaging to look at how a specific network in the brain (called the default mode network) works differently in people with ME/CFS compared to healthy people. Researchers found that in ME/CFS patients, this brain network shows more chaotic activity and weaker communication between different regions. These differences might one day help doctors diagnose ME/CFS using brain scans.
Why It Matters
ME/CFS lacks objective diagnostic biomarkers, forcing reliance on symptom reporting. This study provides evidence that brain imaging could identify consistent neurobiological differences, potentially leading to objective diagnostic tools. Understanding DMN dysfunction may also illuminate the cognitive and fatigue symptoms that characterize ME/CFS.
Observed Findings
BOLD signals in the posterior cingulate cortex were more complex in CFS patients during both resting state and task conditions.
Functional connectivity between the medial prefrontal cortex and both inferior parietal lobules was weaker in CFS patients at rest.
During task performance, connectivity between the medial prefrontal cortex and left inferior parietal lobule, and between mPFC and posterior cingulate cortex, was reduced in CFS.
Dynamic functional connectivity between DMN hubs showed greater complexity in CFS patients during task performance.
Each identified brain difference accounted for 7-11% of the variability in health scores.
Inferred Conclusions
Default mode network activity is characterized by increased complexity and decreased coordination in ME/CFS patients.
Brain network analysis measures show promise as potential diagnostic biomarkers for ME/CFS.
The altered DMN connectivity patterns suggest impaired communication between core brain regions involved in self-referential thinking and cognition.
Remaining Questions
Would these DMN abnormalities be specific to ME/CFS or do they occur in other fatigue-related or neurological conditions?
Do brain imaging measures change with disease progression or treatment, and could they serve as markers of clinical improvement?
What This Study Does Not Prove
This study does not prove that DMN changes cause ME/CFS symptoms or that these brain differences are specific to ME/CFS (other conditions may show similar patterns). As a cross-sectional study, it cannot determine whether brain changes precede symptom onset or result from the disease. The modest effect sizes (7-11% variance explained) mean these measures alone cannot yet reliably diagnose individual patients.
Tags
Symptom:Fatigue
Biomarker:Neuroimaging
Method Flag:PEM Not DefinedSmall SampleExploratory Only