Tag: supplementary motor area connectivity

Microstructural alterations in brain tissue of ME/CFS and long COVID using diffusion tensor imaging and diffusion kurtosis imaging

Abstract:

Introduction: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and long COVID have overlapping symptoms, such as profound fatigue, cognitive impairment, post-exertional malaise, pain and sleep disturbances that are debilitating and reduce quality of life. While Magnetic Resonance Imaging (MRI) techniques, specifically Diffusion Tensor Imaging (DTI) and Diffusion Kurtosis Imaging (DKI), have been used to investigate brain tissue microstructure in ME/CFS or long COVID, no study has yet combined these modalities to directly compare tissue microstructural differences between people living with ME/CFS and long COVID.

Methods: We recruited 37 ME/CFS participants (Age: 43.56 ± 12.5), 19 long COVID participants (Age: 47.92 ± 13.3), and 27 healthy controls (Age: 37.9 ± 10.4). Data were acquired using a 3 Tesla (3T) Prisma MRI scanner. DTI and DKI metrics were determined using MRtrix v3.0.7 and Designer V2.0 software, respectively. Voxel-based statistical analysis of cohort differences was performed using the Statistical Parametric Mapping (SPM12) toolbox in MATLAB. Correlation analysis was performed between DTI, DKI metrics and clinical measures such as duration of illness, fatigue severity, SF36 domains and WHODAS domains.

Results: Compared with healthy controls, individuals with ME/CFS showed microstructural alterations in the cingulum, supplementary motor areas, and parts of the corpus callosum (all p < 0.05). Long COVID participants demonstrated microstructural alterations in regions including the fusiform and precentral gyrus and in major white matter tracks (all p < 0.05). Direct comparisons between ME/CFS and long COVID revealed difference in the left corona radiata (p = 0.001).

Conclusion: This study identifies distinct tissue microstructural alterations in ME/CFS and long COVID and offers a vital insight into the neuropathological basis of shared symptoms in both conditions.

Source: Singh TB, Marshall-Gradisnik S, Barnden L, Eaton-Fitch N, Huynh TH, Inderyas M, Thapaliya K. Microstructural alterations in brain tissue of ME/CFS and long COVID using diffusion tensor imaging and diffusion kurtosis imaging. Front Med (Lausanne). 2026 Jul 17;13:1824498. doi: 10.3389/fmed.2026.1824498. PMID: 42539798; PMCID: PMC13424405. https://pmc.ncbi.nlm.nih.gov/articles/PMC13424405/ (Full text)

Fatigue Is Associated With Altered Monitoring and Preparation of Physical Effort in Patients With Chronic Fatigue Syndrome

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is characterized by disabling fatigue, which is suggested to be maintained by dysfunctional beliefs. Fatigue and its maintenance are recently conceptualized as arising from abnormally precise expectations about bodily inputs and from beliefs of diminished control over bodily states, respectively. This study used functional neuroimaging to identify the neural correlates of fatigue and its maintenance by beliefs during a physical effort task.

METHODS: We isolated behavioral adjustments and cerebral activity during feedback processing and motor preparation, in the context of a task in which patients with CFS (n = 85) and healthy control subjects (n = 29) produced 30%, 50%, and 70% of their right-hand maximal voluntary contraction, and received directional feedback on performance (e.g., too little force).

RESULTS: Patients with CSF showed an effort-dependent behavioral bias toward less effort investment in response to directional feedback for the highest effort level as compared with healthy control subjects. This bias was associated with reduced feedback-related activity in the dorsolateral prefrontal cortex. These effects were proportional to state-related fatigue and prior beliefs about CFS patients’ ability to perform the task. Patients with CFS also showed higher activity in the supplementary motor area, proportional to their state-related fatigue, and reduced connectivity between the supplementary motor area and sensorimotor cortex during motor preparation as compared with control subjects.

CONCLUSIONS: These findings link fatigue symptoms to alterations in behavioral choices on effort investment, prefrontal functioning, and supplementary motor area connectivity, with the dorsolateral prefrontal cortex being associated with prior beliefs about physical abilities.

Copyright © 2018 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Source: van der Schaaf ME, Roelofs K, de Lange FP, Geurts DEM, van der Meer JWM, Knoop H, Toni I. Fatigue Is Associated With Altered Monitoring and Preparation of Physical Effort in Patients With Chronic Fatigue Syndrome. Biol Psychiatry Cogn Neurosci Neuroimaging. 2018 Apr;3(4):392-404. doi: 10.1016/j.bpsc.2018.01.015. Epub 2018 Feb 12. https://www.ncbi.nlm.nih.gov/pubmed/29628071