Light therapy, also known as low level laser therapy or photobiomodulation (PBM), is gaining lots of attention in the health and medical industry, as a tool for improving brain health. Research supports its potential as a complementary treatment option for those with a range of brain conditions such as Parkinson's, dementia, traumatic brain injury, and mental health disorders (1, 2). There's also a growing body of literature supporting its use for enhancing cognitive performance in everyday people (3).
But how does it work?
What is light therapy?
We can intuitively understand that light can positively affect on our bodies. For example, being in the sun can help us produce Vitamin D, regulate our circadian rhythms and sleep, and even improve our mood.
Light therapy is an extension of this - it harnesses specific wavelengths of light to target parts of the body for a therapeutic effect.
4 ways light therapy can support brain health
It is worth noting that light therapy is a relatively new area of medicine and therefore research into efficacy and placebo effects is ongoing. However, there are already over 6000 published papers on light therapy for various conditions, with even more to come.
So, what happens when we use light therapy on the brain? However, here is what research data has gathered so far.
1) It can stimulate mitochondria to energise cells.
Research is suggesting that light therapy can stimulate the mitochondria to produce more energy (2).
Why is this important?
Our bodies are made of cells and the mitochondria is the cell's "battery”, where energy is created to carry out important activities such as repairing the body and helping it function.This energy is known as adenosine triphosphate (ATP).
When we're stressed, unwell, or simply ageing, these mitochondria don't work as well. This is called mitochondrial dysfunction or insufficiency, and has been associated with many chronic conditions, including brain conditions. For example developing Alzheimer's disease, Alzheimer’s, metabolic conditions, cardiovascular diseases and chronic pain (4).
How can light therapy help? By stimulating the mitochondria to produce more energy, our brain cells have more capacity to grow, repair and regulate healthy cellular activities. This is particularly helpful in supporting brain health, because the brain is the most energy-demanding organ in the body (it constitutes only 2% of body weight, yet consuming 20% of our energy supplies (5)). The sheer quantity of mitochondria in our brain cells makes it a particularly useful organ to target with light therapy.
2) It can reduce inflammation and oxidative stress.
Neuroinflammation (inflammation of the brain) has been linked with a variety of neurological disorders, including Parkinson’s, Alzheimer’s, mental health issues, brain fog and memory problems (2, 6, 7).
Oxidative stress occurs when there is an imbalance between ROS, and our body's ability to neutralise them with antioxidants. Oxidative stress can lead to many chronic and neurodegenerative conditions, such as cancer, cardiovascular diseases, or Parkinson's.
How can light therapy help? Research suggests that light therapy can assist with both of the above, due to their anti-inflammatory and anti-oxidating capabilities, allowing for a healthy brain (2, 6, 7). It appears that light therapy triggers both anti-inflammatory and anti-oxidating cascades, which can accelerate healing and repair in both acute and chronic conditions (2, 6, 7).
3) It can improve circulation of oxygenated blood.
Improved circulation helps transport fresh nutrients to the brain and remove toxins, which build up either due to illness, or naturally over the course of a day.
How can light therapy help? Data suggests that light therapy can cause the dissociation of nitric oxide, which then helps to regulate and improve blood flow to the brain, and therefore improve circulation to keep the brain healthy.
4) It can modulate natural brainwaves.
Research suggests that light therapy can also help modulate our natural brainwave patterns (2). Our brain naturally produces electrical impulses, known as brainwaves, which help the nerve cells to function and communicate with one another.
The 5 brainwaves are:
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Gamma
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Beta
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Alpha
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Theta
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Delta
Each brainwave is associated with a different state of mind. For example, alpha (8-12 Hz) is the primary kind of brainwave pattern when we're in a calm, relaxed state. 40+ Hz, on the other hand, is the frequency of gamma waves, which are particularly important for focus, alertness, and movement control (9).
Gamma brainwaves are the fastest of our 5 natural brainwaves. They are active when we are most alert and focused, and are critical for memory, learning, and concentration.
The link between brain waves and Parkinson's
Gamma brainwaves affected in a number of conditions, including Parkinson’s (9). In fact, providing electrical impulses to modulate brainwave patterns is one way Deep Brain Stimulation (DBS) surgery is believed to help Parkinson's disease. Although DBS typically uses a higher frequency than light therapy (60-200 Hz, as opposed to 40 Hz with light therapy), they all work within the frequency of gamma.
It may be that light therapy may offer a natural, non-invasive, cost-friendly treatment to also help modulate brainwave patterns, that doesn't require surgery or specialist referral.
What are the potential benefits?
Whilst research is ongoing into how light therapy can help you maintain a healthy brain, here are some of the benefits that research papers have uncovered.
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Focus and concentration
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Mood
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Memory
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Information processing
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Perception
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Learning capacity
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Problem-solving skills, multi-tasking, decision-making, resource management, logic, and pattern recognition
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Mental acuity and sharpness
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Energy levels
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Cognitive health and function
It can also:
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Promote relaxation
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Assist with managing stress, which is beneficial for sleep and can also positively impact digestive health and the gut-brain connection
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Support mental wellbeing
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Support your brain's natural activities
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Improve overall wellbeing, health, and wellness
As we age, it is common to start experiencing cognitive decline such as worsening memory, attention, and other aspects of cognition. That's another reason why prioritising brain health is important.
How much light penetrates through to the brain?
It's important to state that a large part of the light that is emitted by a helmet is absorbed by the cells in the skin, fascia, blood, nerves, skull and other vessels more superficial to the brain, rather than the brain itself (10). Only a small percentage penetrates through the skull to the brain.
However, research has shown that near infrared light, which we cannot see, can penetrate through the skull to stimulate brain tissue (1, 2). Specifically, 810 nm is the wavelength that's been shown to be most appropriate for directly treating the brain (1, 2, 10).
Red light, on the other hand, does not have the ability to penetrate as deeply through the skull (1, 2, 10).
3 tips to choose the right light therapy technologies to support brain function and health
It's important to understand that not all devices are made equal. There are three main factors that impact the quality of the product you are receiving such as diode placement, wavelength, and frequency. These factors are all really important to ensure that the helmet you're using is having the desired effect, so let's talk a little more about each of these features.
1. Diode placement
Perhaps one of the most important features to consider, is what parts of the brain the device shines the light on. This is because different parts of the brain control different aspects of our health. For example, the front part of our brain is particularly important for cognitive functions and social interaction, whereas the sides are important for emotional control and memory, and the back part of our brain is famously connected to vision.
Light diodes are the parts of the device where the light comes out of. They can either be like small light bulbs (LEDs), or a laser. Therefore, the placement of these light diodes will impact which parts of the brain is targeted.
2. Wavelength of light
Wavelength is another important factor that you should always consider when you're looking at a light therapy device. This is because different wavelengths have different depths of penetration. Depending on what issue you are trying to treat, this becomes an important consideration.
To learn more about depth of penetration of red and infrared light therapy particular, you may want to read "What's the difference between infrared and red light therapy? What you should know before purchasing.".
3. Frequency
As discussed already, light therapy has been shown to be able to modulate brainwaves (2). This is why the frequency (Hz) of a device is really important. If someone has issues with cognition or alertness, or has a neurodegenerative condition, such as Parkinson's, research suggests that their gamma waves (40+ Hz) may be aberrant (9). Therefore, they may wish to look for a device that pulses at 40 Hz.
Still have questions?
If you're unsure which helmet might be right for you, you may want to consider getting the opinion of a health professional. For example, the SYMBYX Clinical Support team is a network of practising health professionals. They're a team of international clinicians who're highly skilled in using light therapy, and can determine what type of helmet may be best for you. You can email your questions through to our team at info@symbyxbiome.com.
We hope you found this blog post useful and informative!
References:
1) Salehpour F, Mahmoudi J, Kamari F, Sadigh-Eteghad S, Rasta SH, Hamblin MR. Brain Photobiomodulation Therapy: a Narrative Review. Mol Neurobiol. 2018 Aug;55(8):6601-6636.
2) Salehpour F, Sadigh-Eteghad S, Mahmoudi J, Kamari F, Cassano P, Hamblin MR (2023). Photobiomodulation for the Brain: Photobiomodulation Therapy in Neurology and Neuropsychiatry. Springer Charm. https://doi.org/10.1007/978-3-031-36231-6.
3) Salehpour F, Majdi A, Pazhuhi M, Ghasemi F, Khademi M, Pashazadeh F, Hamblin MR, Cassano P. Transcranial Photobiomodulation Improves Cognitive Performance in Young Healthy Adults: A Systematic Review and Meta-Analysis. Photobiomodul Photomed Laser Surg. 2019 Oct;37(10):635-643.
4) Zong, Y., Li, H., Liao, P. et al. Mitochondrial dysfunction: mechanisms and advances in therapy. Sig Transduct Target Ther 9, 124 (2024). https://doi.org/10.1038/s41392-024-01839-8
5) Mergenthaler P, Lindauer U, Dienel GA, Meisel A. Sugar for the brain: the role of glucose in physiological and pathological brain function. Trends Neurosci. 2013 Oct;36(10):587-97. doi: 10.1016/j.tins.2013.07.001. Epub 2013 Aug 20. PMID: 23968694; PMCID: PMC3900881.
6) Hamblin MR. Mechanisms and applications of the anti-inflammatory effects of photobiomodulation. AIMS Biophys. 2017;4(3):337-361.
7) Cardoso FDS, Salehpour F, Coimbra NC, Gonzalez-Lima F, Gomes da Silva S. Photobiomodulation for the treatment of neuroinflammation: A systematic review of controlled laboratory animal studies. Front Neurosci. 2022 Sep 20;16:1006031
8) Reddy OC, van der Werf YD. The Sleeping Brain: Harnessing the Power of the Glymphatic System through Lifestyle Choices. Brain Sci. 2020 Nov 17;10(11):868. doi: 10.3390/brainsci10110868. PMID: 33212927; PMCID: PMC7698404.
9) Guan Ao , Wang Shaoshuang , Huang Ailing , Qiu Chenyue , Li Yansong , Li Xuying , Wang Jinfei , Wang Qiang , Deng Bin. The role of gamma oscillations in central nervous system diseases: Mechanism and treatment. Frontiers in Cellular Neuroscience. 2022; 16.
10) Henderson T. Can infrared light really be doing what we claim it is doing? Infrared light penetration principles, practices, and limitations. Frontiers in Neurology. 2024; 15. 10.3389/fneur.2024.1398894.
11) Wu T, Hallett M. The cerebellum in Parkinson's disease. Brain. 2013 Mar;136(Pt 3):696-709. doi: 10.1093/brain/aws360. Epub 2013 Feb 11. PMID: 23404337; PMCID: PMC7273201.
12) Seidel K, Mahlke J, Siswanto S, Krüger R, Heinsen H, Auburger G, Bouzrou M, Grinberg LT, Wicht H, Korf HW, den Dunnen W, Rüb U. The brainstem pathologies of Parkinson's disease and dementia with Lewy bodies. Brain Pathol. 2015 Mar;25(2):121-35. doi: 10.1111/bpa.12168. Epub 2014 Sep 12. PMID: 24995389; PMCID: PMC4397912.
13) Calabresi, P., Mechelli, A., Natale, G. et al. Alpha-synuclein in Parkinson’s disease and other synucleinopathies: from overt neurodegeneration back to early synaptic dysfunction. Cell Death Dis 14, 176 (2023). https://doi.org/10.1038/s41419-023-05672-9
