Do you have COVID fog, TBI, PTSD or other brain damage? New research found that Long-COVID is characterized by traumatic brain injury (TBI) in some people (Agoston 2024, unpublished). Learn how brain damage can be reversed to help you regain function again. Check out our page on why your brain may need healing.
*Kai L's (32 year old woman) story: a Native American military veteran with double brain trauma.
"I was diagnosed with a traumatic brain injury (TBI) after serving in the Air Force. I had developed coping skills for my TBI and was doing well until I developed Long Covid. Suddenly my brain was like alphabet soup. I couldn't’ ‘find’ the words to reply or even speak. I felt out of it and like I was in a fog most of the time. Couldn't remember what I did an hour before ... lost motivation to care for myself.
My TBI symptoms became worse and I was no longer able to compensate for it. I had reoccurring headaches. I couldn't sleep and I started showing signs of PTSD."
To make matters worse, Kai also had shortness of breath, heart palpitations and chronic fatigue. She used to love backpacking but now got tired walking around her house. Due to her illness she lost over 20 pounds which she didn't need to lose.
Why does ethnicity matter? People of different ethnic backgrounds have different reactions to COVID. This may be due to genetics or to socioeconomic factors. American Natives, Native Hawaiians, Hispanics and Black Americans had higher rates of COVID mortality when compare to White Americans (Faust et al. 2024).
Check out: Brain cell regeneration starter kit. Your guide to practical information on how to heal your brain.
Damaged brain and neuron cells can revert back to an embryonic or infant state. Like new babies, these regressed brain cells can regrow back normally. The regrown brain cells develop new connections and can restore lost brain functions (Poplawski et al. 2020, Cao et al. 2021).
After a seizure, specialized neuroimmune cells called microglia hop into action. Microglia (a subset of glial cells) are found in the brain and contribute to brain development, homeostasis, and synaptic plasticity (changes in nerve rewiring used in making memories) (Sierra et al. 2019). These small cells produce brain-derived neurotrophic factor (BDNF) which influences the functional and structural properties of neurons. This promotes learning and memory (Parkhurst et al. 2014).
When nerve cells are injured the microglia form pouches called microglial process pouches. These pouches gently tend to the injured and swollen nerves and their branches (dendrites) (Eyo et al. 2021). This helps the injured brain cells heal.
How do you do this? Exercise, sleeping 7-8 hours a night, reducing stress, eating a healthy low inflammation diet and learning new skills all have been shown to promote new brain cell growth.
Here are some quick and easy ways to grow new brain cells (See Train Your Brain for more tips):
✿ Do tasks with your non-dominant hand. Ambidexterous? Use your toes! Try brushing your teeth with the 'wrong' hand.
✿ Drive or walk to work or school using a different route.
✿ React or respond to someone or something in a different manner than you normally do.
✿ Take 5-20 minutes to learn something new each day. Try a language app or a YouTube tutorial series in anything that interests you.
✿ Try to do something you normally find difficult.
✿ Eliminate people who are sources of stress from your life.
✿ Add antiinflammatory foods to your diet.
You can speed this process up by learning new skills and tasks. It doesn't matter how long your brain has been damaged; your brain can relearn tasks when motivated.
Synapses are junctions or connections between two nerve cells. The synapse is a small gap where the nerve cells are close together but do not touch. Electrical and/or chemical signals jump or flow across this gap. This allows the nerve cells to communicate.
Silent synapses are immature or inactive connections between neurons. It is believed that the human brain contains millions of silent synapses. These inactive synapses are bored and always on the lookout for new information and connections. Once exposed to new information they become active and can form new memories and skills. Previously inactive synapses can be used to replace damaged neurons or learn new skills (Vardalaki et al. 2022). This helps your brain remain plastic throughout life.
In a randomized double blind study, Killgore et al. 2020 gave 32 adults (18-48 years old) with a mild traumatic brain injury (TMI) either a cube that emitted blue light (peak wavelength of 469 nm) or a placebo cube emitting amber light (peak wavelength of 578 nm). They used the light for 6 weeks of 30-minutes in the morning.
People using the blue light fell asleep faster and woke up one hour earlier in the morning compared to the people using the amber placebo light. The blue light group felt more alert during the day. Blue light exposure suppresses melatonin
Due to the blue light treatment, people improved their brain processing speed and efficiency. In addition, the size of the pulvinar nucleus, a part of the brain responsible for visual attention, increased. The blue light group strengthened their neuron connections and the communication flow between the pulvinar nucleus and other parts of the brain that promote alertness and cognition (Killgore et al. 2020, Killgore et al. 2022). These benefits may be due to the positive effects of blue light on sleep.
In a similar but larger study, Raikes et al 2022 reported that people with mild TBI who received blue light treatment for 30 minutes daily for 6 weeks had greater growth in 15 areas of the brain than people receiving amber light treatment. Blue light therapy was associated with moderate to large increases in brain gray matter volume. Increased functional connectivity was observed in areas and cognitive networks associated with sleep regulation as well as daytime cognitive function, alertness, and attention. People receiving blue light therapy reported less daytime sleepiness.
Other studies have found similar benefits for people with PTSD. Kilgore et al. 2022 reported that morning exposure to blue light in people with PTSD was associated with improvements in sleep duration. They also had an increased volume of the left amygdala when compared with people treated with amber placebo light. The changes in the amygdala volume were directly correlated with sleep improvement.
Neurons only make up half of your brains cells. The other half are comprised of glial cells (glia); part of the neuroimmune system. The neuroimmune system is the interaction between the nervous system and the immune system.
Brain inflammation, viruses, bacteria, injury, and stress can transform helpful glial cells into reactive or activated glial cells. Activated or reactive glia respond to chemicals produced by cytokines, neurotransmitters, neurodegeneration, growth factors, damage-associated molecular patterns (DAMPs), and pathogen-associated molecular patterns (PAMPs) (see Giovannoni and Quintana 2020 for more). There are many types of glia including astrocytes, radial glia, ependymal cells, oligodendrocytes, schwann cells, bergmann glia,satellite cells, and microglial cells.
While reading about glia you may come across the terms reactive and activated. Some scientists use the term reactive for transformed astrocytes and activated for transformed microglia. To me, it makes sense to think of it as the cells are activated (by injury or inflammation) and this causes them to become reactive. Normally I use the term activated glia because I like how it makes them sound like superheros (or supervillians). Bennett and Viaene (2020) do a deep dive into this nomenclature if you are interested.
I know, DAMPs and PAMPs either sound like a questionable investment strategy or some sort of NSFW role playing. Actually they both describe patterns recognized by your body.
Pathogen-associated molecular patterns (PAMPs) are patterns that occur in pathogens. For example, let's say that all viruses in family Bee wear a yellow and black striped sweater vest and black boots. Your body recognizes this family pattern when it see it and attacks the viruses.
Likewise, damage-associated molecular patterns (DAMPs) are patterns that occur when cells are damaged or stressed. Injured cells release a set of danger chemicals to warn other cells. Your healthy cells can recognize these chemicals and react. Click here to see the role of glial cells in your brain and central nervous system (CNS).
New brain cells have been documented in the:
✿ Limbic system: this is a cluster of brain structures in the cerebral cortex that are responsible for behavioral and emotional responses. This group includes the hippocampus, amygdala, and hypothalamus.
✿ Hippocampus: this is part of the limbic system. Hippocampal function plays a critical role in learning, emotional responses, and memory formation and storage. The dentate gyrus of the hippocampus continually generates and integrates new neuron into existing neural networks through your lifetime (Cope and Gould 2019, Abbott and Nigussie 2020). Adult neurogenesis in this area may provide some resilience to stress and anxiety (see discussion in Cope and Gould 2019).
✿ Amygdala: processes fearful and threatening information; evaluates things in the environment to determine their importance; promotes strong emotions like fear, anger, aggression and pleasure; and helps form memories.
✿ Subventricular zone: contains neural stem cells that can develop into different mature brain cells (Baur et al. 2022).
✿ Hypothalamus: regulates energy balance and food intake; may grow new brain cells in order to respond to changes in diet (Recabal et al. 2017).
✿ Olfactory bulb: you continually generate new neurons in this area that interweave into the existing cells (Lledo and Valley 2016). If you have lost your sense of smell due to long COVID there is a good chance that new neurons can help you regain it. One thing to try is olfactory training.
✿ Cerebral cortex: Ohira 2021 looks at the increasing evidence that neurogenesis occurs in the adult cerebral cortex.
✿ Want to learn more about new neurons? Check out the discussions about neurogenesis in Fowler et al. 2008, Kumar et al. 2019, and Jurkowski et al. 2020.
*Names and some minor identifying details in all stories in this website are changed to protect people's privacy.
This information in this website is for informational purposes only and does not constitute medical advice, diagnosis, or treatment.
Abbott LC, Nigussie F. Adult neurogenesis in the mammalian dentate gyrus. Anat Histol Embryol. 2020 Jan;49(1):3-16. doi: 10.1111/ahe.12496. Abstract.
Agoston DV. Traumatic Brain Injury in the Long-COVID Era. Neurotrauma Rep. 2024 Jan 30;5(1):81-94. doi: 10.1089/neur.2023.0067. Full article.
Baur K, Abdullah Y, Mandl C, Hölzl-Wenig G, Shi Y, Edelkraut U, Khatri P, Hagenston AM, Irmler M, Beckers J, Ciccolini F. A novel stem cell type at the basal side of the subventricular zone maintains adult neurogenesis. EMBO Rep. 2022 Sep 5;23(9):e54078. doi: 10.15252/embr.202154078. Full article.
Bennett ML, Viaene AN. What are activated and reactive glia and what is their role in neurodegeneration? Neurobiol Dis. 2021 Jan;148:105172. doi: 10.1016/j.nbd.2020.105172. Full article.
Cao L, Wang Y, Huang Z. Reversion of Injured Adult Neurons to an Embryonic State by Grafts of Neural Progenitor Cells After Spinal Cord Injury. Neurosci Bull. 2021 Feb;37(2):271-274. doi: 10.1007/s12264-020-00584-6. Full article.
Christensen J, Wright DK, Yamakawa GR, Shultz SR, Mychasiuk R. Repetitive Mild Traumatic Brain Injury Alters Glymphatic Clearance Rates in Limbic Structures of Adolescent Female Rats. Sci Rep. 2020 Apr 10;10(1):6254. doi: 10.1038/s41598-020-63022-7. Full article.
Cope EC, Gould E. Adult Neurogenesis, Glia, and the Extracellular Matrix. Cell Stem Cell. 2019 May 2;24(5):690-705. doi: 10.1016/j.stem.2019.03.023. Full article.
Eyo UB, Haruwaka K, Mo M, Campos-Salazar AB, Wang L, Speros XS 4th, Sabu S, Xu P, Wu LJ. Microglia provide structural resolution to injured dendrites after severe seizures. Cell Rep. 2021 May 4;35(5):109080. doi: 10.1016/j.celrep.2021.109080. Full article.
Faust JS, Renton B, Bongiovanni T, Chen AJ, Sheares KD, Du C, Essien UR, Fuentes-Afflick E, Haywood T, Khera R, King T, Li SX, Lin Z, Lu Y, Marshall ADA, Ndumele CD, Opara I, Loarte-Rodriguez T, Sawano M, Taparra K, Taylor HA, Watson KE, Yancy CW, Krumholz HM. Racial and Ethnic Disparities in Age-Specific All-Cause Mortality During the COVID-19 Pandemic. JAMA Netw Open. 2024 Oct 1;7(10):e2438918. doi: 10.1001/jamanetworkopen.2024.38918. Full article.
Fowler CD, Liu Y, Wang Z. Estrogen and adult neurogenesis in the amygdala and hypothalamus. Brain Res Rev. 2008 Mar;57(2):342-51. doi: 10.1016/j.brainresrev.2007.06.011. Full article.
Giovannoni F, Quintana FJ. The Role of Astrocytes in CNS Inflammation. Trends Immunol. 2020 Sep;41(9):805-819. doi: 10.1016/j.it.2020.07.007. Epub 2020 Aug 13. Full article.
Jessen NA, Munk AS, Lundgaard I, Nedergaard M. The Glymphatic System: A Beginner's Guide. Neurochem Res. 2015 Dec;40(12):2583-99. doi: 10.1007/s11064-015-1581-6. Full article.
Jurkowski MP, Bettio L, K Woo E, Patten A, Yau SY, Gil-Mohapel J. Beyond the Hippocampus and the SVZ: Adult Neurogenesis Throughout the Brain. Front Cell Neurosci. 2020 Sep 29;14:576444. doi: 10.3389/fncel.2020.576444. Full article.
Killgore WDS, Vanuk JR, Dailey NS. Treatment with morning blue light increases left amygdala volume and sleep duration among individuals with posttraumatic stress disorder. Front Behav Neurosci. 2022 Sep 12;16:910239. doi: 10.3389/fnbeh.2022.910239. Full article.
Kumar A, Pareek V, Faiq MA, Ghosh SK, Kumari C. ADULT NEUROGENESIS IN HUMANS: A Review of Basic Concepts, History, Current Research, and Clinical Implications. Innov Clin Neurosci. 2019 May 1;16(5-6):30-37. Full article.
Lledo PM, Valley M. Adult Olfactory Bulb Neurogenesis. Cold Spring Harb Perspect Biol. 2016 Aug 1;8(8):a018945. doi: 10.1101/cshperspect.a018945. Full article.
Mathias JL, Alvaro PK. Prevalence of sleep disturbances, disorders, and problems following traumatic brain injury: a meta-analysis. Sleep Med. 2012 Aug;13(7):898-905. doi: 10.1016/j.sleep.2012.04.006. Summary.
Ohira, K. Cortical adult neurogenesis and its biological implication. Clin Exp Neuroimmunol. 2023; 14: 44-51. doi: org/10.1111/cen3.12652. Full article.
Opendak M, Briones BA, Gould E. Social behavior, hormones and adult neurogenesis. Front Neuroendocrinol. 2016 Apr;41:71-86. doi: 10.1016/j.yfrne.2016.02.002. Summary.
Parkhurst CN, Yang G, Ninan I, Savas JN, Yates JR 3rd, Lafaille JJ, Hempstead BL, Littman DR, Gan WB. Microglia promote learning-dependent synapse formation through brain-derived neurotrophic factor. Cell. 2013 Dec 19;155(7):1596-609. doi: 10.1016/j.cell.2013.11.030. Full article.
Raikes AC, Dailey NS, Forbeck B, Alkozei A, Killgore WDS. Daily Morning Blue Light Therapy for Post-mTBI Sleep Disruption: Effects on Brain Structure and Function. Front Neurol. 2021 Feb 5;12:625431. doi: 10.3389/fneur.2021.625431. Full article.
Killgore WDS, Vanuk JR, Shane BR, Weber M, Bajaj S. A randomized, double-blind, placebo-controlled trial of blue wavelength light exposure on sleep and recovery of brain structure, function, and cognition following mild traumatic brain injury. Neurobiol Dis. 2020 Feb;134:104679. doi: 10.1016/j.nbd.2019.104679. Full article.
Piantino J, Schwartz DL, Luther M, Newgard C, Silbert L, Raskind M, Pagulayan K, Kleinhans N, Iliff J, Peskind E. Link between Mild Traumatic Brain Injury, Poor Sleep, and Magnetic Resonance Imaging: Visible Perivascular Spaces in Veterans. J Neurotrauma. 2021 Sep 1;38(17):2391-2399. doi: 10.1089/neu.2020.7447. Full article.
Poplawski GHD, Kawaguchi R, Van Niekerk E, Lu P, Mehta N, Canete P, Lie R, Dragatsis I, Meves JM, Zheng B, Coppola G, Tuszynski MH. Injured adult neurons regress to an embryonic transcriptional growth state. Nature. 2020 May;581(7806):77-82. doi: 10.1038/s41586-020-2200-5. Abstract.
Recabal A, Caprile T, García-Robles MLA. Hypothalamic Neurogenesis as an Adaptive Metabolic Mechanism. Front Neurosci. 2017 Apr 5;11:190. doi: 10.3389/fnins.2017.00190. Full article.
Sierra A, Paolicelli RC, Kettenmann H. Cien Años de Microglía: Milestones in a Century of Microglial Research. Trends Neurosci. 2019 Nov;42(11):778-792. doi: 10.1016/j.tins.2019.09.004. Full article.
Vardalaki D, Chung K, Harnett MT. Filopodia are a structural substrate for silent synapses in adult neocortex. Nature. 2022 Dec;612(7939):323-327. doi: 10.1038/s41586-022-05483-6. Abstract.