Covid may alter brain, according to scans

According to a study, catching Covid can trigger brain abnormalities. Before and after infection, scientists discovered substantial variations in MRI (magnetic resonance imaging) scans.

The overall size of the brain had shrunk slightly even after a moderate infection, with less grey matter in the areas of the brain connected to smell and memory.

The researchers are unsure if the changes are permanent, but they do believe the brain can repair.

“We were looking at essentially mild infection, so to see that we could really see some differences in their brain and how much their brain had changed compared to those who had not been infected was quite a surprise,” said lead author Prof Gwenaelle Douaud of the Wellcome Centre for Integrative Neuroimaging at the University of Oxford.

The UK Biobank project, which has been following the health of 500,000 people for almost 15 years and contains a database of scans taken before the pandemic, offers a unique chance to investigate the virus’s long-term health effects.

The researchers rescanned:

Participants in the 401(k) plan On average, 4.5 months after their infection, 96 percent of those infected had mild Covid.
384 people who had never had Covid before
They discovered:

The overall size of infected subjects’ brains had reduced by 0.2 to 2%.
Grey matter was lost in the olfactory areas, which are associated to smell, and memory regions.
Complex mental tasks were more difficult to execute for those who had recently recovered from Covid.

However, the researchers are unsure whether the changes are reversible or actually beneficial to one’s health and well-being.

“It’s important to remember that the brain is highly plastic – that is, it can mend itself – so there’s a good probability that the detrimental effects of infection will fade with time,” Prof Douaud added.

 

The olfactory areas lost the most grey matter, however it’s unclear if te virus affects this region directly or whether cells just die off due to lack of function when persons with Covid lose their sense of smell.

It’s also uncertain if all viral versions inflict this kind of damage.

When the original virus and alpha variant were prominent, and loss of smell and taste was a primary symptom, the scans were conducted.

However, the number of persons infected with the more recent Omicron strain who report this symptom has plummeted.

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‘What is being exercised is your mind,’ says Paola Totaro.

When Paula Totaro caught Covid in March 2020, she lost her sense of smell.

“It was like living in a bubble or a vacuum when it was gone – I found it incredibly isolated,” she told BBC News.

She began scent training after contacting the charity AbScent, which helps people who have lost their sense to smell and taste.

“What scent training does is it requires you to absorb the fragrance, allow it to go back into your nose, and then think about what it is that you’re smelling,” she explained.”And what is being exercised is the relationship between what is in the external world and what goes into your brain and psyche.”

Ms. Totaro has regained the majority of her sense of smell, albeit she still has difficulty distinguishing between distinct aromas.