Not long into the COVID-19 pandemic, infected individuals began reporting cognitive issues, commonly called "brain fog."
So, what exactly is it?
People said they were having issues with attention, concentration, retrieving words and names, processing speeds and working memory.
Dr. Joanna Hellmuth, a neurologist and assistant professor in the UCSF Memory and Aging Center, said on KCBS Radio’s "Ask An Expert" that the issues fall into the domain of executive functioning, or how the brain organizes or plans the other functions of the brain.
Hellmuth said that they’re trying to determine whether the virus is actually doing something to the brain or the brain is reacting to what’s happening elsewhere in the body.
"There’s a few possible mechanisms that could be causing this," the doctor noted. "One, you could theorize, perhaps the virus is getting into the brain early on in the disease and damaging the brain or transiently causing problems in the brain."
There’s some data that supports this and some that doesn’t, Hellmuth said.
"When we actually look for the virus in the brain fluid of individuals, which we can do with a spinal tap, a lot of people who were really sick in the hospital with COVID with neurologic problems - we’re not finding the virus in their brain fluid," she told KCBS Radio. "So, maybe we’re not looking at the right time or maybe the virus got in earlier - we don’t know."
Hellmuth said maybe the virus isn’t getting into the brains of most people, and the immune system’s response to the virus is actually causing the problems.
She finds the other symptoms that people who have COVID-19 report interesting because they all provide clues as to what mechanisms are causing the neurocognitive issues. Other symptoms many patients experience are nerve issues, loss of taste and smell, headaches and autonomic symptoms.
