People with “chemo brain” and covid brain fog could not seem more different: Those with “chemo brain” have a life-threatening disease for which they’ve taken toxic drugs or radiation. Many of those with covid brain fog, in contrast, describe themselves as previously healthy people who have had a relatively mild infection that felt like a cold.
So when Stanford University neuroscientist Michelle Monje began studies on long covid, she was fascinated to find similar changes among patients in both groups, in specialized brain cells that serve as the organ’s surveillance and defense system.
“It was really quite striking,” Monje said.
In cancer patients undergoing treatment, a malfunction in those same cells, known as microglia, are believed to be a cause of the fuzzy thinking that many describe.
Monje’s project is part of a crucial and growing body of research that suggests similarities in the mechanisms of post-covid cognitive changes and other long-studied brain conditions, including “chemo brain,” Alzheimer’s and other post-viral syndromes following infections with influenza, Epstein-Barr, HIV or Ebola.
“There is humongous overlap” between long covid and these other conditions, said Avindra Nath, intramural clinical director of the neurological disorders and stroke unit of the National Institutes of Health.
