What We Know and Don’t Know About Neurological Symptoms from Long COVID Like Brain Fog and Fatigue

Graphic text: What do you know about Covid-19?

In the world of brain injury, healthcare professionals often say, “When you’ve seen one brain injury, you’ve seen one brain injury.” The same assertion seems to apply to what is called long COVID — what the Centers for Disease Control and Prevention (CDC) describes as post-COVID conditions that can have a wide range of symptoms, lasting more than four weeks or even months after infection. Sometimes the symptoms can even go away or come back again…. Oftentimes, these post-COVID symptoms cannot be explained by tests.

Long COVID: What we know and don’t know at this point

Long COVID does not discriminate. People of every age, gender, and ethnicity can suffer. The CDC states, “Post-COVID conditions are found more often in people who had severe COVID-19 illness, but anyone who has been infected with the virus that causes COVID-19 can experience post-COVID conditions, even people who had mild illness or no symptoms from COVID-19.”

“Long COVID is an umbrella term for the many post-acute consequences that result from COVID-19. The more we learn, the more we see that COVID-19 can affect nearly every organ in the body — from the heart and brain to the lungs, kidneys, skin, and gastrointestinal (GI) tract,” says Ziyad Al-Aly, M.D., chief of Research and Development Service at Veterans Affairs St. Louis Health Care System. “We are still learning, but we need to listen to our patients, validate their experiences, and treat their symptoms.”

And the symptoms run the gamut. 

Here is a list of post-COVID conditions that people most commonly report, prepared by the CDC:

General symptoms

  • Tiredness or fatigue that interferes with daily life
  • Symptoms that get worse after physical or mental effort (also known as “post-exertional malaise”)
  • Fever

Respiratory and heart symptoms

  • Difficulty breathing or shortness of breath
  • Cough
  • Chest pain
  • Fast-beating or pounding heart (also known as heart palpitations)

Neurological symptoms

  • Difficulty thinking or concentrating (sometimes referred to as “brain fog”)
  • Headache
  • Sleep problems
  • Dizziness when you stand up (lightheadedness)
  • Pins-and-needles feelings
  • Change in smell or taste
  • Depression or anxiety
  • Digestive symptoms
  • Diarrhea
  • Stomach pain

Other symptoms

  • Joint or muscle pain
  • Rash
  • Changes in menstrual cycles

“And although the research is still in early stages, some experts believe that COVID-19 may either accelerate the progression of an underlying disease or result in a new disease that the patient would not have otherwise experienced without COVID-19,” says Dr. Al-Aly. “Both scenarios are very possible.”

Meghan O’Rourke in her book, The Invisible Kingdom: Reimaging Chronic Illness (Riverhead Books, Penguin, 2022), asserts, “The COVID-19 pandemic has given us a keen sense of how variable the human response to infection can be, vividly dramatizing the ways that a virus or bacterium (or multiple viruses and bacteria) can collide with an individual’s biology to unleash a host of perplexing aftereffects in the body, often incited by the individual’s immune system.”

Voices of Long COVID

While living in New York City, 20 years into a rich and fulfilling career at the United Nations, Sarah R., 48, contracted COVID in March 2020 during the first wave. She had a low temperature and felt tired, but nothing too different from any other flu she had ever had. After a few weeks of lethargy, she felt fully recovered and resumed her pre-COVID life of daily runs and UN projects as a speech writer and policy analyst. Three weeks later, however, she woke up feeling as if she was “being invaded by an alien.” Most of her hair fell out, she lost weight, she felt exhausted all the time, and brain fog and the inability to make connections made writing her complex reports for work all but impossible. And then she started feeling numb and tingly; she felt like she was being physically pulled and tightly wrapped with plastic wire, in particular around her throat, eyes, mouth, arms, hips, and pelvic floor. 

For three years, she saw countless doctors in numerous fields of expertise and underwent more tests than she can remember. She lost her job, her partner, and finally moved back to Minnesota to live with her parents. Finally, she was diagnosed with dystonia — what the National Institute of Neurological Disorders and Stroke defines as “a disorder characterized by involuntary muscle contractions that cause slow repetitive movements or abnormal postures. The movements may be painful, and some individuals with dystonia may have a tremor or other neurological symptoms.” 

The dystonia accounts for some of Sarah’s post-COVID symptoms, but not all.

“My life has transformed. I am no longer a high-powered part of the UN; my ambitions are now scaled way back. I was once on top of the world looking up, now I am looking behind me and down … but trying so very hard not to look too far down,” says Sarah. “The worst parts of the last three years have been the not knowing, the lack of diagnoses, the physical, emotional, and social changes that have come with these chronic conditions, and worst, the feelings shame and helplessness. I don’t really recognize who I have become.”

Holly K., also in her mid-40s, says that before she developed long COVID symptoms — debilitating fatigue, brain fog, and ongoing GI issues — her “energy bucket” felt limitless and full of joy. A university professor for more than 15 years, Holly says, “My whole identity as a professional and a multi-taking single parent has changed. Before getting sick, I’d take my kids on bike rides, to the library, on picnics. I listened to podcasts and loved book clubs. Now, I have to respect my cerebral, cognitive, and physical limitations. I have to teach from home. I can only drive my kids to school in the morning — a few blocks from home. I have other people set up to pick them up from school and drive them to activities or friends’ houses. Sometimes getting dressed or cooking one dish sucks all the energy out of the bucket. Everything comes at a cost. If I didn’t have my mother, sister, and step-mother to help, I would not be able to work or take care of my kids.” 

Since having COVID in December 2021, Holly has seen 15 doctors across multiple disciplines. She has been told to take vitamins. She has been diagnosed with Epstein-Barr, imbalanced hormones, and anxiety. “The brain fog, in particular, makes me feel like I’m not in the same room as everyone else … as if there is a barrier between us or that I am in a different dimension.”

Both women say they are grateful for many of their doctors — for their concern, honesty, and support — but at the end of the day, they feel alone and often “out of medical options.”

“We see a lot of patients with symptoms from long COVID also struggling with mental health issues like depression and anxiety. The research tells us that there is a bidirectional relationship between mental health symptoms and COVID. Having a history or predisposition to depression and anxiety, for example, appears to be a risk factor for long COVID symptoms, but COVID itself is associated with new onset mental health difficulties in people with no such history,” says Tracy Vannorsdall, Ph.D., associate professor of Psychiatry and Behavioral Sciences, Johns Hopkins School of Medicine. “We do want our patients to know that they are not alone and that we will help them manage their symptoms with existing interventions as well as with new treatments developed specifically for COVID-19.”

Sarah and Holly are just two examples of the 1 out of 5 American adults suffering with the myriad — and often baffling — effects of long COVID.

What we know from the research to date

To date, researchers and clinicians are learning as much as they can about the short- and long-term physical and neurological effects from COVID-19 in both individuals who were hospitalized with severe illness and those who experienced mild illness or no symptoms at all —but there is a long way to go. 

A study of tens of thousands of people in Scotland found that nearly half of people who had COVID have yet to fully recover months after their illness. The good news from the study, however, showed that people who were vaccinated but still infected with the virus were far less likely than those who were not vaccinated to manifest long COVID symptoms.

Another study, co-authored by Dr. Al-Aly, published in Nature Medicine, found that people who were infected with the COVID-19 virus (hospitalized and non-hospitalized) are at a higher rise of various brain injuries than those who were not infected, in particular brain fog, which can hinder every part of cognition, making people feel incredibly adrift. Specifically, people with COVID had a 77 percent higher risk of memory problems compared with the control group.

In May 2020, Igor Koralnik, M.D., chief of Neuro-infectious Disease and Global Neurology, Northwestern Feinberg School of Medicine, along with his team, opened the Neuro COVID-19 Clinic at Northwestern Memorial Hospital, one of the first of its kind in the country. Its goal was not only to treat patients but also to collect data on demographics, quality of life, and cognitive test results related to COVID-19. And in September 2020, they opened the Comprehensive COVID-19 Center, which spans 12 specialties; to date, they have seen more than 1,600 patients. As Mark Caro writes in his article, “The Long Haul” in Chicago magazine, “Koralnik and his team have authored a dozen COVID-related papers, with three more on the way, and their work has drawn much attention in the medical world and beyond. Koralnik uses Altmetric, a data tracking tool, to monitor the many mentions of their research across social and traditional media. ‘It’s important in the sense that people learn about what you’re doing, and so they learn about what long COVID is doing to the brain,’ [Koralnik] says. A paper he wrote … published in July by the journal Neurotherapeutics states that given the large number of individuals experiencing a diminished quality of life and productivity, the neurological manifestations of long COVID are ‘likely to have major and long-lasting personal, public health, and economic consequences.’ It notes the ‘critical need’ for a greater understanding of how the disease works and the development of therapies to treat these serious, persistent symptoms.”

So, what are the main take-aways from these and myriad other studies? Long COVID can affect anyone no matter their demographic and no matter the severity of the illness. Post-COVID symptoms can span multiple organs. Symptoms can resolve only to return, or resolve completely. Symptoms can last weeks, months, or even years. Some go away. Others may not. More research is needed.

“The bottom line is that we are still learning. The studies are helpful but we need more in-depth research … descriptions of trees, not descriptions of forests,” says James Jackson, Psy.D., director of Behavioral Health at the ICU Recovery Center at Vanderbilt University.

Dr. Jackson writes in his forthcoming book, Clearing the Fog: From Surviving to Thriving with Long COVID — A Practical Guide (Little Brown Spark, May 2023), “The research on long COVID that is emerging from medical trials and investigations, and is published in prestigious academic journals, describes the experience of thousands of patients through figures, graphs, and mean and median scores. But in my clinic and support groups, and in others around the world, we see what these data represent in our patients’ daily lives as they deal with the frustrating reality of symptoms like brain fog. They know firsthand the ramifications of living with cognitive impairment, which include problems in attention, executive functioning, memory, and processing speed, and daily problems in functioning.”

Dr. Al-Aly adds, “What is most important right now is to leverage what we know and urgently develop clear clinical care guidelines and an action plan to train clinicians and healthcare providers out there who many know little to nothing about post-COVID conditions.” 

COVID clinics 

Clinics like Dr. Koralnik’s at Northwestern and John Hopkins’ Post-Acute COVID-19 Team (JH PACT) Program, of which Dr. Vannorsdall is a part, are running tests and offering strategies and support for their patients but there is long wait for appointments, oftentimes up to many months.

And, there is the whole question of accessibility and equity of care and insurance. Getting help for post-COVID symptoms should not be a privilege.

“There can definitely be long waits to get into post-COVID clinics just like there are now often long waits these days for mental health care,” says Dr. Vannorsdall. “But I think the pandemic has given society at large an opportunity to have more of a conversation about and appreciation of mental health as an integral component of our physical health. Physical and mental health should not be treated as two separate entities. At JH PACT, we work with patients symptom by symptom, mostly through cognitive behavioral therapy (CBT); sleep hygiene; fatigue management and energy conservation; compensatory strategies; and acceptance and commitment therapy. Most importantly, we want our patients to know that our expectation is that they will get better over time, and that while they are dealing with symptoms, we are here to help them thrive, not simply survive.”


Both Dr. Koralnik and Dr. Al-Aly speak of taking an “all hands-on-deck approach” to learning about the physical, psychological, and day-to-day impacts of long COVID and developing more effective and pointed treatments based on the expanding research. And that takes critical funding, education, and guidelines for clinical care. 

“If we study long COVID and figure it out, what we learn may help us figure out other complex syndromes like post-Lyme disease and chronic fatigue syndrome, for example,” says Dr. Koralnik. And “figuring it out” not only means finding answers to how and why COVID can affect multiple organs in the short and long term, but, while long COVID still exists, how to get people back into their lives … cooking, socializing, sending emails, focusing on a book or movie, one small activity, one step, one gain at a time.

“There are rays of hope. We do want our patients to know that they are not alone. We want them to know that lots of people are working day and night to crack this long COVID and that we are learning more and developing better ways to treat these varied symptoms,” says Dr. Al-Aly. “But this is an international health crisis — an urgent situation — and we can’t let it go on too long. We need funding for research, more professional development across the board to take care of people with long COVID, and most importantly, a cultivation of better understanding of this new disease and empathy for the people impacted.”

Posted on BrainLine November 14, 2022. Reviewed February 2, 2023.