Covid-19 might cause long-term brain tissue loss, which might have long-term implications, according to a study.
A continuing U.K Biobank study has found that loss of brain tissue may explain why patients lost their sense of smell.
For a before-and-after comparison, researchers invited 394 survivors and 388 healthy volunteers to return for follow-up scans. Most survivors reported either mild-to-moderate symptoms, or none at all, and 15 had been hospitalized.
Researchers discovered "significant" loss of gray matter in brain areas associated with smell and taste in the survivors.
The researchers highlighted ahead of peer review that several of the affected brain regions are also involved in the recall of experiences that trigger emotional response.
The changes were not observed in the noninfected group. More research is needed, according to the authors, to establish if survivors would have problems remembering emotionally charged situations in the long run.
They also don't know if the gray matter loss is due to the virus moving into the brain or another effect of the disease.
"Our findings thus consistently relate to loss of gray matter in limbic cortical areas directly linked to the primary olfactory and gustatory system," the authors wrote, or areas in the brain related to the perception of senses such as smell and taste.
The gray matter in our brains is a part of our central nervous system and, in essence, governs all of our brain's functions. It allows people to regulate their movements, memories and emotions, thus an anomaly in the gray matter of the brain can have an effect on communication skills and brain cells.
This finding is consistent with a study published in The Lancet Psychiatry journal in 2020, which suggested that serious infections may harm the brain, causing long-term consequences such as stroke or dementia-like symptoms.
