Transient resting-state salience-limbic co-activation patterns in functional neurological disorders, 2024, Weber et al

Highlights

• Patients entered more frequently into insular-somatomotor co-activation.
  
  
• Patients entered less often into insular co-activation with subcortical regions.
  
  
• Dynamic alterations correlated with alpha-amylase and duration of illness.
  
  
• Functional alterations reflect prioritizing allostatic mechanisms due to alert.

Abstract

Background
Functional neurological disorders were historically regarded as the manifestation of a dynamic brain lesion which might be linked to trauma or stress, although this association has not yet been directly tested yet. Analysing large-scale brain network dynamics at rest in relation to stress biomarkers assessed by salivary cortisol and amylase could provide new insights into the pathophysiology of functional neurological symptoms.

Methods
Case-control resting-state functional magnetic resonance imaging study of 79 patients with mixed functional neurological disorders (i.e., functional movement disorders, functional seizures, persistent perceptual-postural dizziness) and 74 age- and sex-matched healthy controls. Using a two-step hierarchical data-driven neuroimaging approach, static functional connectivity was first computed between 17 resting-state networks. Second, dynamic alterations in these networks were examined using co-activation pattern analysis. Using a partial least squares correlation analysis, the multivariate pattern of correlation between altered temporal characteristics and stress biomarkers as well as clinical scores were evaluated.

Results
Compared to healthy controls, patients presented with functional aberrancies of the salience-limbic network connectivity. Thus, the insula and amygdala were selected as seed-regions for the subsequent analyses. Insular co-(de)activation patterns related to the salience network, the somatomotor network and the default mode network were detected, which patients entered more frequently than controls. Moreover, an insular co-(de)activation pattern with subcortical regions together with a wide-spread co-(de)activation with diverse cortical networks was detected, which patients entered less frequently than controls. In patients, dynamic alterations conjointly correlated with amylase measures and duration of symptoms.

Conclusion
The relationship between alterations in insular co-activation patterns, stress biomarkers and clinical data proposes inter-related mechanisms involved in stress regulation and functional (network) integration. In summary, altered functional brain network dynamics were identified in patients with functional neurological disorder supporting previously raised concepts of impaired attentional and interoceptive processing.

Open access, https://www.sciencedirect.com/science/article/pii/S2213158224000226

 

There is no such thing as stress biomarkers. In almost all instances where 'stress' is used, they can be substituted with exertion or other labels and actually gain meaning, especially if the meaning respects the context. However much they want to make cortisol a marker of stress, the carelessness with which they pretend that it is so while insisting that chronic illness has no biomarkers means they're fake illnesses is just impressive double standards.

Also: what the hell is a dynamic brain lesion?

So, not a lesion. Gotcha. Words and their meaning, so inconvenient at times, convenient at others, as long as you don't really bother adhering to their meaning.

An entire imaginary area of medicine built on weak correlations and lies, damn lies and complete bullshit. And they expect it to somehow work. Good grief.