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https://theconversation.com/long-covid-how-lost-connections-between-nerve-cells-in-the-brain-may-explain-cognitive-symptoms-192702>
"For a portion of people who get COVID, symptoms continue for months or even
years after the initial infection. This is commonly referred to as “long
COVID”.
Some people with long COVID complain of “brain fog”, which includes a wide
variety of cognitive symptoms affecting memory, concentration, sleep and
speech. There’s also growing concern about findings that people who have had
COVID are at increased risk of developing brain disorders, such as dementia.
Scientists are working to understand how exactly a COVID infection affects the
human brain. But this is difficult to study, because we can’t experiment on
living people’s brains. One way around this is to create organoids, which are
miniature organs grown from stem cells.
In a recent study, we created brain organoids a little bigger than a pinhead
and infected them with SARS-CoV-2, the virus that causes COVID-19.
In these organoids, we found that an excessive number of synapses (the
connections between brain cells) were eliminated – more than you would expect
to see in a normal brain.
Synapses are important because they allow neurons to communicate with each
other. Still, the elimination of a certain amount of inactive synapses is part
of normal brain function. The brain essentially gets rid of old connections
when they’re no longer needed, and makes way for new connections, allowing for
more efficient functioning.
One of the crucial functions of the brain’s immune cells, or microglia, is to
prune these inactive synapses.
The exaggerated elimination of synapses we saw in the COVID-infected models
could explain why some people have cognitive symptoms as part of long COVID."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
