Tiejun Tang, Ying Zhang
"Brain fog" is not a medical terminology, but a colloquial term used to describe slow or fuzzy thinking and slowed-down cognitive response. The symptoms are various depending on different body constitution, such as confusion, memory loss, difficult recalling words, slow thinking, difficulty concentrating, and being easily distracted. Symptoms of brain fog can appear during the recovery period after many viral infections. Serena Spudich, a professor of neurology at Yale University, reported that a person seems to experience more cognitive slowing and emotional problems after contracting the coronavirus than most of other viral infections.Neurological symptoms occurred in 80% of hospitalized patients with COVID-19 investigated in one study..A survey study published in Eclinical Medicine, The Lancet showed that in 3,762 people with confirmed or suspected COVID-19, 85% reported brain fog . A cohort study based on linked electronic health records data from 81 million patients including 273,618 COVID-19 survivors, 36.55% of people have sequelae during the 3-6 months. This condition, often referred to as long COVID, a common and particularly difficult problem with long COVID is brain fog. Why does brain fog occur? How to diagnose and treat brain fog in traditional Chinese medicine and western medicine? These questions are important in the long-term treatment of COVID-19 and significant to a nation’s medical system. In this work, we aim to provide an alternative view (TCM) in treating brain fog.
The Mechanism of Brain Fog and the Pathogenesis of TCM
The reason of brain fog is not very clear in modern medicine, but Dr. Spudich believes the most likely cause was inflammation caused by the body's immune response, rather than the virus itself. A study issued in the March 2021 found autoantibodies in the cerebrospinal fluid of COVID-19 patients with neurological symptoms . This result suggests that the generation of brain fog may have its pathological material basis, and it is not entirely a psychological problem. It's also possible that the virus itself has somehow entered the brain, possibly by spreading through the top of the nose or by infecting cells known to cross the blood-brain barrier. But in a study by Columbia University published in September 2021, no evidence of coronavirus RNA or protein was found in brain cell samples from 41 people who died of COVID-19 but a recent study published in Nature shows strong evidence for brain-related abnormalities in COVID-19. In this study, researchers investigated brain changes in 785 UK-based participants (aged 51-81 years) who underwent imaging twice and found reduced grey matter thickness and tissue contrast in the orbitofrontal cortex and para hippocampal gyrus, which is correlated with changes in functionally relevant regional tissue damage markers, and overall causing brain-capacity reduction. This explains why infected participants also exhibited greater cognitive decline on average between the two time points.
However, whether such deleterious effects can be partially reversed or whether these effects will persist in the long term remains to be further investigated..
Traditional Chinese Medicine Theory believes that people's spiritual consciousness activities are dominated by the heart. "Huangdi Neijing" (Inner Canon of the Yellow Emperor) recorded: "The heart is the official of the monarch, whom in charge of the consciousness." ZHANG Jiebin (a Chinese Physician, 1563-1640) explained: "The heart is the king of a body, with a vain spirit and it has the ability to cope with many changes. All the internal organs and the whole body are controlled by heart, thus, wisdom and spiritual comes from the heart. And the consciousness comes from heart". In the words of Traditional Chinese Medicine, the brain belongs to the "extraordinary Fu-organ ", with a function in regulating mental activities. JIN Zhengxi (1598-1645) of the China’s Yuan Dynasty said: "The memory and people's inspirations lie in the brain. Children's brains are not full but with gradual growing. Old people’s brainis gradually empty, therefore with memory declining."
There have been some debates in the field of Chinese medicine about whether the heart dominatesmind or the brain dominates mind. Professor DENG Tietao (the author’s supervisor) published "The scientific evidence of the Theory of Heart Dominates the Mind" in the journal of New Chinese Medicinewith an opinion that “the theory of heart dominating the mind comes from practice, which in turn can guide clinical practice. Practice is the criterion for testing the truth. Therefore, this theory is scientific”.One of my articles "A Joined Discussion about the Heart and Brain Dominating the Mind" extended Deng’s work by arguing the mechanism of heart dominating mind as the root, and the brain dominating the mind as the branch . In my opinion, although western medicine believes that the brain fog comes from the brain, its origin does come from the heart. According to the principle that treatment must be based on the origin of the pathology, the treatment of brain fog should therefore focus on nourishing the heart and calm the mind at the same time, while taking the opening of the orifices of brain into account.
In addition, according to the TCM,(1) the kidneys govern the bones, and the bones generate marrow, while the marrow nourishes the brain, so nourishing the kidneys and filling essence is to nourish the brain; (2) the liver controls stagnation, regulates qi, thus, relieving the stagnation of liver qi helps relieving depression; (3) spleen is the source of qi and blood, meanwhile related to thinking . Strengthening the spleen and nourishing qi can also indirectly nourish the heart and calm the nerves. Although brain fog is in the brain, to regulate the function of five Zang organs can achieve the purpose of treatment. In particular, nourishing the heart and calming the nerves should be the focus.
Chinese and Western Medicine in Treatment of Brain Fog
Western Medicine Treatment
Western medicine believes that cognitive rehabilitation seems to be the best way to treat brain fog. Cognitive rehabilitation is like physical therapy, but it targets the brain. Usually performed by a neuropsychologist, and the treatment consists of written and oral exams and focuses on strategies to improve certain functions, such as attention or memory. Many hospitals in the U.S. currently have cognitive rehabilitation programs, and many long COVID clinics also offer brain fog treatment. There is some evidence that playing games like CogMed, Lumosity, etc. on a computer or mobile phone can also improve cognitive performance. It can be a great addition to cognitive rehabilitation therapy.
In terms of drug therapy, the United Kingdom has recently launched a combination preparation for the treatment of brain fog called Brainzyme, which includes EMT mixture (theanine, EGCG and polyphenols), guarana seeds, choline, ginkgo biloba, L-Tyrosine, Piperine, Bromelain, Maca Root, Vitamins and Minerals. Among them, ginkgo biloba and pepper are the ingredients of traditional Chinese medicine, and the others are mostly nutritional additives, which are also contained in many traditional Chinese medicines. The efficacy of Brainzyme in the treatment of brain fog has not been reported.
Traditional Chinese Medicine Treatment
Traditional Chinese Medicine treats brain fog according to the principle of syndrome differentiation and treatment. In clinical treatment, I found that there are mainly four common syndromes.
(1) Heart-blood deficiency and heart-yin deficiency:
Main symptoms: Memory loss, lack of concentration, insomnia and dreaminess, dizziness and fatigue, pale complexion or red cheeks, or night sweats or spontaneously sweat, pale tongue or red tongue with little coating, deep and thin pulse.
Treatment principles: Nourishing yin and nourishing blood, calming the mind and the nerves.
Formula selection: Modified BaiziZixinWan.
Herbs selection:Baiziren, Xuanshen, Shudihuang, Gouqizi, Zhigancao, Danggui, Shichangpu, Maimendong, Fuling.
For those with more blood deficiency, add Jixueteng.Heshouwu;
For those with more Yin deficiency, add Baihe, Tianmendong;
For those with sleep disorders, add Suanzaoren, Yejiaoteng.
(2) Disharmony between the heart and kidney:
Main symptoms: Forgetfulness, insomnia, trance, dizziness, palpitations, soreness and weakness of waist and knees, hot flashes and night sweats, tinnitus, red tongue with little or no coating, rapid pulse.
Treatment principles: Nourish yin and calm the mind, regulate heart and kidney.
Formula Selection: Tianwang Buxin Dan
Herbs selection: Baiziren, Suanzaoren, Maimendong, Tianmendong, Shengdihuang, Xuanshen, Taizishen, Wuweizi, Danggui, Yuanzhi, Hehuanpi, Yizhiren.
If the kidney deficiency is the main reason, add Xuduan, Duzhong;
If the heart fire is inflamed, add Zhizi, Huanglian.
(3) Liver qi stagnation:
Main symptoms: Depression, restlessness, irritability, forgetfulness, dreaminess, dizziness, hypochondriac distension, red eyes and bitter mouth, thin white or yellow tongue coating, wiry pulse.
Treatment principles: Soothe the liver and relieve depression, calm the heart and mind.
Formula Selection: Modified XiaoyaoWan
Herbs selection: Chaihu, Danggui, Baishao, Fushen, Baizhu, Xiangfu, Qingpi, Yujin, Zhigancao.
For the cases of live fire excess, add Mudanpi, Zhizi;
For cases with severe emotional depression, add Suxinhua, Meiguihua,Jianghuang;
For the cases of bitter taste in the mouth add Longdancao, Xiakucao.
（4）Heart and spleen deficiency:
Main symptoms: Forgetfulness, anxiety, lack of concentration, fatigue, palpitations, insomnia, loose stools, or abdominal distention, pale tongue, fat tongue with tooth marks, white and slippery coating, slow pulse.
Treatment principle: Nourish the heart and spleen, soothe the nerves.
Formula Selection: Modified Guipi Wan.
Herbs selection: Renshen, Huangqi, Baizhu, Danggui, Fushen, Yuanzhi, Suanzaoren, Longyanrou, Wuweizi, Zhigancao.
For those with spleen deficiency and loose stools; add Yiyiren, Cheqianzi;
For those with abdominal distension, add Muxiang, Sharen;
For those with poor appetite add Maiya, Guya;
For those with severe memory loss, add Yizhiren and Shichangpu.
In addition to herbal treatment, acupuncture is also an effective means of treating post-COVID-19 brain fog. Mainly select the points on the Heart Meridian of Hand Shaoyin, the Pericardial Meridian of Hand Jueyin, the Liver Meridian of Foot Jueyin, the Kidney Meridian of Foot Shaoyin, the Du meridian, and local acupuncture points on the head. Scalp acupuncture can also be used entirely, or electro-acupuncture can be added.
Healthy dietary can also help brain fog recovery. A healthy diet (including olive oil, fruits and vegetables, nuts and legumes, and whole grains) has been shown to improve thinking and memory. Avoid alcohol and drugs. Getting enough sleep, listening to music, regular aerobic exercise, and participating in social activities can also help eliminatethe symptoms of brain fog.
Brain fog is very common in the duration of COVID 19 infection and its aftermath. Western Medicine usually applies cognitive rehabilitation therapy to treat Brain Fog, while Traditional Chinese Medicine apply herbals to treat based on a TCM theory that many organs (liver, kidneys, spleen) can affect on brain capacity, however, the brain is mainly charged by the heart. This paper suggests that Chinese herbal medicine can be a very effective alternative or/and supplement treatment to eliminate Brain Fog, with the principle of combining heart and brain in the treatment, by nourishing the heart, tranquilizing the mind, clearing the orifices, and refreshing the brain.
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