Before contracting COVID-19, in November 2020, Amy Engkjer was fit, healthy, happy — and busy. She worked out three times a week, hiked regularly with her husband near their home in Missoula, Mont., ran a stained-glass business, and taught meditation.
COVID hit her hard. She suffered from fever, cough, loss of taste and smell, intense fatigue, numbness, pain, seizure-like episodes, brain fog, dizziness, and migraine attacks. Weeks after her initial infection, the list of her symptoms, including tachycardia (a racing heart), trembling hands, and problems with temperature regulation, grew longer. “Days turned into weeks and then months,” she recalls. It was anguish.
Meditation had long been part of her routine, but now she was unable to calm her mind or body. She did notice, however, that her symptoms seemed to get worse when she took in alarming stories and news reports about long COVID. And they improved when she avoided those stories and focused on nurturing feelings of hope.
What Engkjer stumbled upon was a link between her nervous system and her chronic-pain symptoms — a connection that has begun receiving more attention from researchers and health practitioners alike.
“Much of the autonomic nervous system is fragile, so any kind of severe infection, physical trauma, or emotional trauma has the capacity to result in dysfunction of autonomic functions, which include things like temperature regulation, heart rate, and blood pressure,” says Gregory Plotnikoff, MD, MTS, FACP, a functional-medicine practitioner in Minneapolis.
Researchers are still trying to understand how these connections between the brain and the body might support healing from long COVID and other chronic conditions. This is some of what they’re learning.
The Plastic Brain
In the thick of her illness, Engkjer read a book called The Brain That Changes Itself by psychiatrist Norman Doidge, MD. His focus is neuroplasticity — the ability of neurons in the brain to adapt, reorganize, and recover from trauma. Neurologists once believed the brain only generated new neurons before birth, but studies of neuroplasticity have revealed that the brain adapts throughout our lives.
“I had this idea right away that neuroplasticity could be a really big factor here,” Engkjer says. That the concept had played a role in her symptoms made sense to her. It also offered a way forward.
Many brain-retraining techniques center around neuroplasticity, including those used to help people recover from strokes and traumatic brain injuries. (These focus on retraining a healthy area of the brain to take over the functions of a damaged part.) Practitioners are now using these approaches to treat a broader range of conditions, including chronic fatigue syndrome, fibromyalgia, post-treatment Lyme disease, and multiple chemical sensitivity.
Annie Hopper, a limbic-system rehabilitation specialist and founder of the Dynamic Neural Retraining System, believes disorganized neural circuits — which can be the result of severe inflammatory illness — can lead to any of these conditions. As such, they’re akin to an acquired brain injury, one that can be healed using principles of neuroplasticity.
Engkjer began focusing on her brain to heal from long COVID. “I regularly saw a neurologist and a physical therapist. I did neurofeedback, which helped to stabilize my brain. I adopted an anti-inflammatory diet, got shiatsu, worked with neurolinguistic programming, did EMDR [eye-movement desensitization and reprocessing], even took ice-cold showers and tried IV therapy.”
Her symptoms improved, but progress was slow and setbacks frequent.
Then, about 11 months into her long-COVID ordeal, Engkjer came across the story of Paul Garner, MD, an emeritus professor at the Liverpool School of Tropical Medicine in England. He’d recovered from long COVID using brain-retraining techniques.
Brain retraining is rooted in the idea that some chronic conditions and unexplained symptoms are due not to bodily damage but to faulty signaling from the nervous system. “The brain gets ‘stuck’ in an unconscious state of chronic emergency that perpetuates illness and inflammation,” explains Hopper in her book, Wired for Healing.
Brain retraining uses tools that harness neuroplasticity to relax the threat response, normalize neural pathways, improve overall function, and reduce or eliminate symptoms.
“Everything finally clicked,” Engkjer says. “I realized I’ve been in this looping fight-or-flight pattern for so long, and I finally understood what the mechanism was.”
A year and a half after her initial COVID infection, Engkjer decided to try the Lightning Process, a mind–body training program developed by Phil Parker, PhD, that aims to help develop new neural circuits in the brain.
The Lightning Process teaches you to pause, notice the habitual reaction to your symptoms, recognize the fight-or-flight response, interrupt this pattern, and override it with messages of safety. It asks you to savor memories of feeling healthy, then move and speak as if you were in that healthier state now.
If the brain leads, in other words, the body will follow.
The Brain’s Alarm System
Physical symptoms like pain and fatigue serve as signals from the unconscious nervous system, explains physician and long-COVID specialist Rebecca Kennedy, MD, in an interview broadcast on YouTube; the body urges us to retreat and rest to boost our odds of survival.
“When the body responds to illness, our feelings and behaviors change,” writes Stockholm University professor of psychoneuroimmunology Mats Lekander, PhD, in The Inflamed Feeling: The Brain’s Role in Immune Defense. “In the short term, this seems to be a good strategy to promote our natural healing mechanisms. But in the longer term, if the reaction doesn’t shut itself down, it is not such a good thing.”
To call off a state of alarm, the brain must convey a message of safety to the body. To do this deliberately may literally sound like wishful thinking. But the brain’s ability to create changes in physiology has been well-studied — down to specific inflammatory responses.
In a study published in Cell in 2021, researchers added a chemical to the drinking water of mice that triggered a bout of colitis. They marked the neurons in the brains of the mice that became active when their intestinal inflammation peaked. Several weeks later, the researchers reactivated the neurons — which prompted a similar inflammatory response in the colon.
The idea that the brain can spark symptoms without a pathological cause is not new. In 1885, researchers stimulated symptoms in a woman with a pollen allergy by exposing her to an artificial flower she believed real.
Brain-retraining programs aim to reeducate these responses by teaching the brain to more accurately distinguish the difference between apparent and actual threats. This helps the body return to a state of safety where it can unconsciously begin to downshift any protective sickness response.
A growing evidence base offers qualified support for brain retraining’s efficacy. The process has helped relieve symptoms from multiple sclerosis, chronic fatigue syndrome, and chronic-pain conditions. Published in 2021, a systematic review of studies seemed to largely support its use, though it acknowledged not all participants found relief.
Engkjer was among those whose results were positive. “I thought I would just go through the process and see if it could help with the few things I wasn’t completely over. It ended up taking these concepts I knew theoretically and making them real. I could almost feel these new neural pathways in my brain starting to line up, and symptoms and beliefs that had come up before began to atrophy.”
Now fully recovered, Engkjer has become a passionate advocate for the tools that helped her heal. She started a nonprofit called Positively COVID, where she shares patient-recovery stories along with education and resources on mind–body tools for healing.
No one knows how many people have used brain retraining to recover from long COVID, but there are plenty of positive testimonials in online forums and videos as well as in patient-support groups.
There are also plenty of people who have tried brain retraining without success. Like most healing modalities, it can be powerful for some and have no impact for others.
Even when it does help, it’s rarely a one-size-fits-all solution, and finding an effective approach often requires persistence, patience, and trial and error. For some, the obstacles to healing have been years in the making.
The Biology of Threat
Threat signaling in the nervous system can result in conditions that are both very real and not pathological. Howard Schubiner, MD, an internal-medicine physician and author of Unlearn Your Pain, explains the difference: “When you have cancer or a fracture, that’s a pathological finding — it means there is tissue damage in the body. If you have a high heart rate when you’re stressed, that’s a physiologic finding; there is no tissue damage in the heart, and the heart is under the control of the brain and the nervous system.”
An accumulation of adverse childhood experiences, chronic stress, or trauma — even persistent overtraining without adequate recovery — can increase hypervigilance in the brain, predisposing the nervous system to this kind of “stuck” response.
In a study of 338 COVID patients, those who’d experienced at least one traumatic event during childhood were three times more likely to develop long COVID. Those who’d experienced two or more were at more than five times greater risk.
In a study of 338 COVID patients, those who’d experienced at least one traumatic event during childhood were three times more likely to develop long COVID. Those who’d experienced two or more were at more than five times greater risk.
The COVID pandemic and its disruption to our lives, work, and social connections represented a massive source of stress for us all — an important element to understand in the conversation about long COVID.
The physiological impact of the collective fear and threat that so many of us felt during the global pandemic cannot be underestimated, says Lilia Graue, MD, LMFT, a London-based physician specializing in mind–body medicine. “Even if we weren’t consciously fearful of COVID, our underlying neurophysiology was responding to a present threat that was endangering lives. That activates pathways involving inflammatory mediators and nervous-system structures like the amygdala that respond to danger and create symptoms such as pain or fatigue in order to protect us.”
Still, even those who uphold the nervous-system theory of long COVID do not see it as comprehensive. It’s well understood that many people suffer lasting organ damage after severe COVID. Undetected diabetes, autoimmunity, and thyroid disorders can also contribute to lasting COVID symptoms.
Yet many people have long-COVID symptoms that can’t be explained by known pathological mechanisms. This is where the nervous system can be a useful arena to explore.
“Out of the hundreds of patients I’ve assessed, maybe one or two fit in that category of organ damage. For the majority of long-COVID patients, most likely it’s a nervous-system issue rather than damage in the body,” Kennedy says.
Getting to the Root Cause
Even concrete pathological findings may not offer a consistent explanation for long-COVID symptoms. Many studies have reported abnormal findings in people with long COVID, such as viral remnants, high levels of blood clot–related proteins, microbiome alterations, low cortisol, immune-cell irregularities, reactivated viruses, or dysfunctional mitochondria.
Yet correlation does not necessarily mean causation, Schubiner says. The nervous system is intricately connected to the endocrine and immune systems and has two-way communications.
“When you find these endocrine and immunologic abnormalities, you could presume that they’re the cause of someone’s illness, but it might be that they’re the result of their illness,” he explains. They may be occurring downstream of the root cause, which could be the brain’s alarm system stuck in threat-response mode.
How do all of the pieces fit together?” Kennedy asks. “They fit together great when we’re looking through the lens of the brain and the nervous system, rather than through the lens of the body alone.”
Abnormalities — changes in nerve conduction, microbiome alterations, presence of food-specific immunoglobulin G antibodies, irregular MRI findings, and atypical skin-biopsy findings — have been found in a whole range of what Schubiner calls “nonspecific” conditions, such as back pain, irritable bowel syndrome, chronic fatigue syndrome, and migraine.
“And yet we routinely see people who recover using techniques that rewire the brain’s neural circuits in days, weeks, or months, despite those abnormalities,” Schubiner says.
He’s seen the same rapid recovery in long-COVID patients he’s treated, some of whom had been bedridden. “Many of the symptoms are physiologic abnormalities that are reversible.”
Specifically, they’re reversible when approached through the lens of the nervous system.
“So, how do all of the pieces fit together?” Kennedy asks. “They fit together great when we’re looking through the lens of the brain and the nervous system, rather than through the lens of the body alone.”
Reading the Signs
There are ways to differentiate a pathological condition, such as cancer or heart disease, from a condition driven by a hypervigilant nervous system.
“If the pattern of symptoms does not follow some sort of structural damage in the body — if pain, tingling, numbness, or sensations don’t follow known physiologic pathways of the nerves, if symptoms jump around, or they’re worse sometimes and better other times in a way that doesn’t make sense physiologically — that’s a piece of evidence,” Kennedy says.
A wide range of symptoms in different areas and systems of the body is another clue.
“If the pattern of symptoms does not follow some sort of structural damage in the body — if pain, tingling, numbness, or sensations don’t follow known physiologic pathways of the nerves, if symptoms jump around, or they’re worse sometimes and better other times in a way that doesn’t make sense physiologically — that’s a piece of evidence.”
“The chance that there’s an undiscovered reason due to damage in the body gets less and less with the more symptoms you have,” she adds. “If someone has nerve pain and brain fog and insomnia and a GI disorder and rashes, there is unlikely to be one pathogenic mechanism that’s going to explain all these different things.”
One method Schubiner uses is asking patients to close their eyes and imagine doing some kind of activity, then notice how they feel. “They may say, ‘I feel dizzy,’ or ‘I’m getting chest pain or a headache,’” he says. “It’s a way of demonstrating that maybe it’s not walking that’s causing the symptoms, but it’s the fear in the subconscious brain of walking.”
Understandably, mysterious and debilitating symptoms are scary — and the anxiety they provoke can lead to a feedback loop that makes them worse over time. “Fear strengthens that danger signal in the brain, and then the brain makes symptoms worse,” Schubiner explains. “It’s a feedback loop of pain or fatigue leading to fear of the pain or fatigue, leading to increased pain or fatigue.”
Absorbing the stories of others’ suffering and symptoms often adds more fuel to this fire. This may be a reason to approach social media and online patient forums with caution. Some research has shown that people who are active in online patient forums (specifically patients with chronic fatigue syndrome and fibromyalgia) report greater symptom severity and less improvement than those who choose to leave the groups.
This may, of course, be due to people leaving the community when their symptoms abate. But anecdotally, many people report shifting their focus away from stories of suffering toward stories of healing as being integral to their recovery.
Breaking the Feedback Loop
Unraveling the symptom-fear-symptom feedback loop takes time, patience, and self-compassion, says Graue. And it involves approaches that are both top-down and bottom-up.
Top-down approaches educate people about alternate possible causes for their symptoms. Releasing the conviction that there’s physical damage or an ongoing pathological threat being harbored in the body is key. “Top-down approaches address thoughts and emotions and encourage the reprocessing of sensations,” she explains.
Still, simply addressing the conscious mind isn’t enough. “Breaking free from these loops requires focusing more on the unconscious than the conscious brain,” Plotnikoff notes. “If we could think our way out of it, it wouldn’t be an issue.”
“Breaking free from these loops requires focusing more on the unconscious than the conscious brain,” Plotnikoff notes. “If we could think our way out of it, it wouldn’t be an issue.”
This is why exclusively top-down approaches such as cognitive behavioral therapy (CBT), have had limited results; CBT doesn’t generally include tools to directly calm or reset the nervous system.
Similarly, therapies that encourage physical exercise without first addressing the nervous system can even be counterproductive: If the nervous system sees exercise as a threat, it may exacerbate symptoms as a protective mechanism. “In order for neural circuits to change, the limbic system needs to move out of its chronic alarm state and into a more relaxed state where growth and repair are possible,” writes Hopper.
Bottom-up approaches aim to relax the nervous system, sending signals of calm and safety so it can make that shift. These might include breathwork, meditation, vagal-tone exercises, somatic therapy, or acupuncture.
Shamanic journeying, religious rituals, or various forms of energy healing are other practices that can bypass the rational mind to access deeper parts of the psyche and facilitate emotional release.
Different programs offer various approaches to brain retraining, including the Dynamic Neural Retraining System, Lightning Process, Gupta Program, Curable, pain-reprocessing therapy, emotional awareness and expression therapy, Safe and Sound protocol, and more. (Visit https://www.positivelycovid.org/brain-reprogramming for a thorough list.)
Different people may benefit from different programs or combinations of elements. Some may improve with the first program they try; others may need to experiment. “If you have a functional condition [rather than a pathologic one], the cure can come in a million different ways,” notes Schubiner.
Harnessing the power of the brain to orchestrate healing is also known as the placebo effect. Schubiner describes four necessary components for successful placebo treatment:
- A believable explanation for the problem (for example, a dysregulated nervous system).
- A technique that addresses that explanation (such as tools to calm the nervous system).
- A treatment delivered in the context of a trusting and caring relationship with a provider.
- A person with hope and optimism that it can work.
Because each ingredient is necessary, one may need to make multiple attempts to find the explanation, approach, and provider or guide that makes the most sense — and offers the most hope — for them.
Mixing Hope With Humility
People who recover from chronic conditions using brain retraining can become evangelical about it, says Graue, but it’s important to stay humble.
“There are some people for whom these approaches will have limited utility, particularly if they feel endangered by them,” she notes. “There can be a certainty in statements like, ‘This is helpful for everybody if you just follow steps one, two, and three.’ This leaves many people feeling like they’re doing something wrong, because it’s not working for them.”
Each successful recovery involves individuals who found their own combination of tools and approaches. “Even within mind–body approaches, there’s a wide array of frameworks that will have different usefulness for different people,” she explains. And the patient’s belief that they can heal makes a difference. (Visit “What Is a Functional Neurological Disorder?” to learn how experts are beginning to uncover these mind-body complexities — and how to treat them.)
At the same time, many people feel ongoing resistance to the idea of their pain having a nervous-system component. “People have been really hurt and dismissed in many spaces with the typical narrative that this is all in their heads,” Graue adds. “That fails to acknowledge how real these symptoms are and the impact they have on people’s lives.”
People with chronic-pain conditions have often experienced skepticism from their conventional physicians, who may lack the tools to diagnose and treat their complex symptoms. This leaves many frustrated and hurt as well as eager for a structural explanation for their symptoms so they will be recognized as legitimate. (Check out “How to Manage Chronic Pain — Naturally” to learn more about the challenges of chronic pain conditions.)
Online patient communities and media coverage may reinforce the idea that there must be a biomarker that’s being neglected — and this can amplify the drumbeat of fear, alarm, and despair.
Yet mind–body modalities suggest that the choice between a biomarker and a nervous-system explanation for a chronic illness is a false one. What we really need is a paradigm shift to understand how our brains and bodies interact to create our health, says Graue.
“We need to be doing a better job at going beyond the either-or narrative of mind versus body to a both-and explanation — one that allows for many different pathways to healing.”
