A new study based on data collected by UK Biobank suggests that COVID-19 survivors may suffer gray matter loss over time.
The long-term experiment, which involved 782 volunteers, compared brain scans of people before the pandemic. To draw an analogy between brain scans before and after the pandemic, researchers asked 394 COVID-19 survivors to return for another scan, as well as 388 healthy volunteers.
Among participants who recovered from COVID-19, the researchers saw significant effects of the virus on human brain matter, with loss of gray matter in areas of the brain.
It should be noted that the study has not yet undergone rigorous peer review.
The authors wrote: “Thus, our findings are consistently related to the loss of gray matter in limbic areas of the cerebral cortex directly related to the primary olfactory and gustatory system,” or brain regions associated with the perception of senses such as smell and taste.
The gray matter in our brain is part of the central nervous system and essentially controls all of our brain functions.
It allows people to control movement, memory and emotions, so a disruption in the gray matter of the brain can affect communication skills and brain cells.
The study also suggests that loss of gray matter in memory-related areas of the brain “may in turn increase the risk of developing dementia in these patients in the long term.”
This finding followed a study published last year in the journal Lancet Psychiatry, which suggested that serious COVID-19 infections can damage the brain, leading to long-term complications such as stroke or dementia-like symptoms. The authors noted that more data are needed to adequately assess the effects of COVID-19 on brain health.
Most COVID-19 survivors who participated in the study experienced mild to moderate symptoms or no symptoms at all. This was seen as a merit of the study, as most brain imaging publications have focused on moderate to severe cases of COVID-19.
“There is a fundamental need for more information about the cerebral effects of the disease even in its mildest form,” the Biobank study said.