Post-COVID Fatigue โLinked toโ Reduced Blood Flow in Visual Processing centersโ of the Brain
New research โฃreveals a consistent pattern of reduced blood flow-hypoperfusion-in the right โขoccipital lobe among individuals experiencing persistent fatigue โfollowing a COVID-19 infection. The findings, published in PLoS One, suggestโค a neurological basis for the debilitating fatigue experienced by many in the post-COVID condition, perhaps opening avenues for targeted diagnostic and therapeutic interventions.
Millions worldwide continue to grapple with long-term symptoms after initial COVID-19 infection, collectively known as post-COVID โฃconditionโค or “long COVID.” Fatigue isโ among the most prevalent and disabling of these symptoms, considerably โimpacting quality of life and daily function. This study provides critical evidence linking thisโ fatigue not โtoโค psychological factors alone, but to demonstrable changes in cerebral blood flow, specifically impactingโฃ areas of theโฃ brainโข responsible for visual processing and โspatial awareness. โฃUnderstanding these neurological underpinnings is crucial for developing effective strategies to alleviate the burden of post-COVID fatigue and improve patient outcomes.
Researchers utilized single-photon emission computedโ tomography (SPECT) to assess โฃcerebral blood flow in 36 participants-20 experiencing post-COVID fatigue and โฃ16 healthy controls. SPECT imaging revealedโ significantlyโ decreased regional cerebral blood flow in the right occipital lobe of โขfatigued participants comparedโค to the control group. This hypoperfusion was observed evenโ when accounting for factorsโ like โage, sex, and cardiovascular risk.
The right occipital lobe is critical for processing visualโ information, spatial orientation, and attention-functions often impaired in individuals with post-COVID โขfatigue. This finding aligns with previous research highlighting disruptions in visual processing in post-COVID patients (Renier et al.,โ 2010; de Haas et al., 2021; Friederichs โ& โFriederichs, 2022; Bennett โฃet al., 2020).The study also noted alterations in โฃEEG power spectraโ during simulated driving tasks in โfatigued โindividuals (Makeig,2009; Chuang et al., 2018), suggesting a broader impact on brain function related to cognitive demands.
Notably, theโ observed โฃhypoperfusion wasn’t linkedโ to structural brain changes, as evidencedโ by MRI scans, indicating a functional rather than โstructural deficit. Researchers propose that the reduced โblood flow may contribute to impaired neuronal function and the โsubjective experience of โfatigue. Further inquiry is needed to determine the underlyingโข mechanisms driving this hypoperfusion and to explore potential interventions, such as targeted rehabilitation or pharmacological approaches,โข to restore cerebral blood flow and alleviate fatigue symptoms. A recent study also indicated structural brainโ changes in post-COVID fatigue patients (Heine โฃet al., 2023), suggesting a complexโข interplay between structuralโฃ and functional alterations.
References
* Bennett CR, Bauer CM, Bailin ES, Merabet LB. Neuroplasticity in cerebral visual impairment (CVI): Assessingโ functional vision โคand the neurophysiological correlates of dorsal stream dysfunction. Neurosci Biobehav Rev.2020;108:171-81.
* Chuang C-H,Cao Z,King J-T,wu B-S,Wang Y-K,Lin C-T. brain Electrodynamic and Hemodynamic Signatures Against Fatigue During Driving. Front Neurosci. 2018;12:181.
* โค de Haas B, Sereno MI, Schwarzkopf โDS. Inferior Occipital Gyrus Is Organized โalong Common โคgradients of โขSpatial and Face-Part Selectivity. J neurosci. 2021;41(25):5511-21.
* Friederichs E, Friederichs P.approaching New Clinical Horizons: The Case of Cerebral Visualโค Impairment (CVI). MRAJ. 2022;10(8).
* โฃ Heine J, Schwichtenberg K, hartung TJ, Rekers S, Chien C, Boesl โขF, et โal. Structural brain changes in patients with post-COVID fatigue:โ a prospective observational study.EClinicalMedicine. 2023;58:101874.
*โข Makeig S. Tonic Changesโฃ in EEG Power spectra during Simulated Driving.Lecture Notes in โComputer science. Berlin, Heidelberg: Springer Berlin Heidelberg. 2009. p. 394-403.
*