Frequently Asked Questions about COVID-19 — October 5, 2022

“Shared expectations lead to predictability.”

590.  “Brain fog” is a disabling and not well understood long-COVID condition.

         Q:  What, exactly, is “brain fog”?

         A:  Long-COVID continues to dominate the current reports on research of COVID-19.  Among the more common conditions being discussed are neurological conditions, including severe headaches and “brain fog.”  In a recent article published by National Geographic, long-COVID headaches are contrasted with migraine attacks.  One author stated, “if migraine headaches can be rated as “9 out of 10 in severity, many people have long-COVID headaches that are “20 out of 10.”  In other words, these can become totally debilitating.  Research is underway exploring the changes in the vascular, chemical, and neurologic changes COVID-19 causes leading to this resulting condition.

Ed Yong is a staff writer at The Atlantic.  He won the Pulitzer Prize for Explanatory Reporting for his coverage of the COVID-19 pandemic. On September 22, he published an article entitled,”One of Long-COVID’s Worst Symptoms Is Also Its Most Misunderstood.”  He explained that “brain fog isn’t like a hangover or depression. It’s a disorder of executive function that makes basic cognitive tasks absurdly hard.”  Executive functions are the set of mental abilities that includes focusing attention, holding information in mind, and blocking out distractions. These skills are so foundational that when they crumble, much of a person’s cognitive edifice collapses. Anything involving concentration, multitasking, and planning—that is, almost everything important—becomes absurdly difficult.

Brain fog is by far one of the most disabling and destructive of long-COVID conditions.  Ed states, “It’s also among the most misunderstood.  From 20% to 30% of patients report brain fog three months after their initial infection, as do 65% to 85% of the long-haulers who stay sick for much longer. It can afflict people who were never ill enough to need a ventilator – or any hospital care.  And it can affect young people in the prime of their mental lives.”

Several examples are cited when health workers with brain fog seek care for themselves.  They find that physicians – even those who have treated COVID-19 patients – often fail to recognize this condition.  Patients are diagnosed as having clouded thinking like that which accompanies hangovers, stress, or fatigue.  But, in reality, brain fog involves real changes to the structure and chemistry of the brain. It is definitely not a mood disorder.

In some severe cases, people have to stop driving – suddenly, they can’t remember where they were going.  One case was cited where a woman couldn’t unload her dishwasher because she couldn’t associate the objects inside with where to place them in the cupboard.

Memory suffers, too, but in a different way from degenerative conditions like Alzheimer’s. The memories are there, but with executive function malfunctioning, the brain can neither choose the important things to store nor retrieve that information efficiently.

Most people with brain fog are not so severely affected and gradually improve with time. But even when people recover enough to return to work, they can struggle with minds that are less nimble than before.

The same constellation of problems in the brain also befalls many people living with HIV, after seizures from epilepsy, after seizures, cancer patients experiencing so-called “chemo brain,” and people with several complex chronic illnesses such as fibromyalgia. It’s part of the diagnostic criteria for myalgic encephalomyelitis, also known as chronic fatigue syndrome, or ME/CFS.  Brain fog existed well before COVID, affecting many people whose conditions were often stigmatized, dismissed, or neglected.  But with the large number of cases associated with COVID-19, scientists are now encouraged and focusing on researching this condition seeking its characteristics, its cause, and perhaps its cure.