There is still a lot to learn about how COVID-19 affects the brain and why some are left with brain fog.
For some, it's not thinking as clearly as before. For others, it's constant confusion, forgetfulness and lack of mental clarity.
"A lot of the other brain issues that we see with COVID are not very well understood and the mechanisms behind it can be very challenging to fully understand," said Dr. Mohammed Osman, neurocritical care physician with Texas Health Physicians Group at Texas Health Fort Worth.
Is brain fog caused by an inflammation of certain parts of the brain?
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"There's some research now that is starting to look at the changes in the brain that happened in COVID patients. And one of the things that is gaining interest is the recognition of abnormal tau proteins," said Dr. Osman.
"While that is something that we see quite frequently in conditions that cause inflammation in the brain, it is not something that is normal."
Unfortunately, right now, there is no recommended or evidence-based therapy or treatment for any of these conditions.
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"There is no data right now to completely support that," said Osman.