Wojcik, Grzegorz M, Shriki, Oren, Kwasniewicz, Lukasz et al. · Frontiers in neuroscience · 2023 · DOI
This study looked at brain electrical activity in people who had COVID-19 and experienced 'brain fog'—persistent mental cloudiness that can last several months. Researchers compared three groups using advanced brain scans while people performed thinking tasks, and used computer algorithms to see if they could distinguish between those with brain fog, those without it, and healthy controls. They found measurable differences in brain activity patterns between the groups, suggesting brain fog has a detectable physical basis in the brain.
Brain fog remains poorly understood in post-viral illnesses including ME/CFS, and this study provides objective electrophysiological evidence that cognitive complaints correlate with measurable brain activity changes. Developing biomarkers for brain fog could improve patient recognition, prognosis, and monitoring of recovery—critical for optimizing rehabilitation and return-to-function.
This study does not establish causation or mechanism—only that brain activity patterns differ between groups. The 60-70% classification accuracy means this approach cannot yet reliably diagnose brain fog in individual patients. The authors explicitly note that explaining *why* these differences exist requires much larger cohorts and additional investigation.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
The first block is for the primary paper and is the citation you should use in research work. The atlas-snapshot line only applies if you are specifically referring to this atlas’s reading of the paper on the date shown.
Primary citation
Wojcik, Grzegorz M, Shriki, Oren, Kwasniewicz, Lukasz, Kawiak, Andrzej, Ben-Horin, Yarden, Furman, Sagi, et al. (2023). Investigating brain cortical activity in patients with post-COVID-19 brain fog.. Frontiers in neuroscience. https://doi.org/10.3389/fnins.2023.1019778
BibTeX
@article{mecfsatlas-wojcik-2023-investigating-brain,
author = {Wojcik, Grzegorz M and Shriki, Oren and Kwasniewicz, Lukasz and Kawiak, Andrzej and Ben-Horin, Yarden and Furman, Sagi and Wróbel, Krzysztof and Bartosik, Bernadetta and Panas, Ewelina},
title = {Investigating brain cortical activity in patients with post-COVID-19 brain fog.},
journal = {Frontiers in neuroscience},
year = {2023},
doi = {10.3389/fnins.2023.1019778},
note = {PubMed: 36845422},
url = {https://www.mecfsatlas.com/evidence/wojcik-2023-investigating-brain},
}Atlas snapshot reference
ME/CFS Atlas. Generator v1 / Scanner v1.4 / policy v0.1. Accessed 2026-05-27. https://www.mecfsatlas.com/evidence/wojcik-2023-investigating-brain
Contribute
Private, reviewed by a human. Not a public comment thread.