You will have come across the various names for the use of red and near infrared lights. Michael Hamblin, one of the lead researchers in the area, has summarised the terminology changes beautifully in a recent article called (somewhat dauntingly) Mechanisms and Mitochondrial Redox Signalling in Photobiomodulation. Click here to read the full article.
Low Level Laser Therapy (LLLT)
Almost 50 years ago in Hungary, Endre Mester found by accident, that a low power red laser noticeably improved wound healing.
It was initially thought that light delivered by a laser was the key factor in the wound healing, and so the term Low Level Laser Therapy, abbreviated to LLLT, was developed.
If you put “LLLT” in your favourite search engine, you’ll find a lot of references will pop up.
Once LED lights became available, it was found that light in laser form was not magical or special. The key was the wavelength. Whether from a LED light or a laser, the wavelength in the red to near infrared range was the critical factor.
Lasers need to be handled carefully, as they can be dangerous, whereas LEDs are safe to use, and they can be easily made into a variety of wavelengths. LED development has been a game changer.
As research into lights continued, it was realised that the term Low Level Laser Therapy was problematic because:
‘Nobody had any idea exactly what “low-level” meant’. (Hamblin’s own words).
LED lights were being used more and more in place of lasers.
The discovery that, depending on the “dose”, red lights can have a positive effect and not so positive effect. (See the post on the Goldilocks effect).
In 2016, there was an international agreement to change the terminology.
The term LLLT was abandoned and the term Photobiomodulation was adopted. And of course, it was immediately abbreviated to PBM.
When you return to your search engine, you will find different articles pop up for “Photobiomodulation” and for “PBM”.
I’ll return to this article in future posts as it has more interesting stuff.
Some of the differences between neuroinflammation and neurodegeneration are beautifully explained. Both diagrams come from this article.
Cells in our body and brain produce cytokines, small proteins that are powerful and wilful little beasties. They provide a very effective means of cell communication, and can “orchestrate complex multicellular behaviour”.
Over 300 different cytokines have been identified, but some of them have shown that in one situation they will behave in one way, but in another situation the same cytokine will do the complete opposite.
Cytokines are part of the body and brain’s response to something going wrong. But cytokines themselves can go haywire (called cytokine network dysfunction or dysregulation) and set up and maintain cascades of activity that can ultimately cause harm to the tissue.
In a brain without disease, the immune (white blood) cells stay inside the blood vessel and don’t cross over the blood brain barrier. Meanwhile the brain has its own immune management system, with various cell types actively protecting the brain. These cells include microglia and astrocytes.
In a healthy brain, cytokines are produced by brain cells, they are all best friends and behave themselves with due decorum.
Neurodegenerative diseases include Alzheimer’s, Parkinson’s and ALS (Stephen Hawking’s disease). In these diseases, the immune (white blood) cells do what they are supposed to do, and stay inside the blood vessels.
However, these diseases have their own mechanisms that act on the brain, and not in a good way (more on that another time).
When these changes start, cytokines produced in the brain start to take notice. They ramp up their numbers, roll up their shirtsleeves and expect to sort out the problem pretty quickly. The problem isn’t so easily sorted, though, and as the cytokines keep battling on, their prolonged activity can itself be a danger to the brain. They go haywire, creating cytokine network dysfunction or dysregulation.
Over time, the cytokine dysfunction seems to knock out the cells and disrupt the normal brain function.
In Neuroinflammatory diseases, such as Multiple Sclerosis, Meningitis and Encephalitis, the white blood cells from the blood stream break through the blood-brain barrier, and they start spreading their cytokines into the brain. The cytokines produced by these external cells throw the equivalent of petrol onto a brain fire.
The brain is besieged and not happy.
Why does this matter?
1. It reminds us that brain diseases are complicated, and that every time researchers identify some new part of a disease process, new layers of complexities are revealed.
2. It shows us that while different diseases may have different origins, they stimulate similar responses. For example, the initial brain change in Alzheimer’s and Parkinson’s are quite different, but the brain reaction with the fighting cytokines is similar.
3. Research has shown that red and near infrared light has a direct and positive effect on the activities of some cytokines, increasing the calming cytokines and dowsing the cytokines that promote inflammation.
4. Red and near infrared light seems to reduce cytokine dysregulation, and thus protect brain cells and brain cell function.
Thinking about Alzheimer’s, the drugs developed to treat it have not shown much effectiveness. In theory, and in early research evidence, exploring the use of red and near infrared lights might be a better way to spend medical research dollars.
I watched a lecture by Prof Michael Hamblin, of Harvard University. He is one of the most respected researchers into the use of red and near infrared light. The lecture is behind a paywall, so I can’t give a link to it, alas.
His last slide had a series of questions – things that we don’t yet know.
What are the diseases and conditions that are most responsive to light?
How important is it for light to penetrate into the brain?
What are the effects on other parts of the body (the parts not receiving the red light)?
What is the best way to deliver light?
How important is it to pulse the light (versus continuous)?
How important is the location on the head?
How important is the biphasic response (check out the post on the Goldilocks effect)?
What about cognitive enhancement (meaning using lights to improve brain function in people with no neurological disease)?
What about pre-conditioning (using lights before an intervention to improve function and reduce injury)?
How does photobiomodulation compare to other brain stimulating devices (eg transcranial direct current stimulation)?
Can too much light be given?
I must confess to feeling rather relieved when I first saw this list. I get frustrated about how much I don’t know, and how difficult it is to answer some of the questions from blog readers.
I’m also pretty excited, too. The blog readers who so generously give regular feedback about their experience with red and near infrared lights are actively contributing to knowledge in this whole area. We need every bit of information we can get.
So if you are a quiet user of a red light hat device, please consider being part of citizen science into the effects of red and near infrared lights. I’d love hear from you.
The couple who made the first light hat from the blog instructions (more) reminded me that an Eliza (or in their case, a Daffodil) is more than just an item for use on the head.
Sore knees – put your feet up on the sofa, bring your heel towards your bottom and put your foot in a place that affords a comfortable bend to your knee. Then perch the Eliza on the top of your bended knee and let the light shine around the knee.
Sore toes and bunions – again, put your feet up on the bed or sofa, but this time perch the Eliza light hat over your offending foot.
Sore wrists and fingers – sit wherever you like, but put your hand in the bucket and let the red light shine on your hand.
If you use the red lights daily on sore parts of your anatomy, you will most likely find that the pain levels starts to recede. It’s the daily use that makes it work, so persist with it. Why put up with pain, if there is a way to reduce it without the use of medication.
This whole red light adventure started with a very painful and arthritic knee (more). I still use the lights daily on that knee. It is not acting like an arthritic knee, and I have long ceased using pain medication.
When I first started working with red lights, I found a rather strange device that was being marketed for rhinitis (hayfever). It had two nasal prongs, each with a 660nm light at the end of it, battery operated. The blurb said that the lights were lasers, but they were really LEDs.
I bought a stack of these things and when we tried them, they were immediately christened Rudolph, as they created the perfect red-lit nose.
The first person to be given a Rudolph was of course Max with Parkinson’s Disease, my first guinea pig. All the people involved in the early days of the light adventures were given a Rudolph and instructed to use it at the same time as the one wavelength Eliza light hat.
It has only just occurred that I had neglected the value of the Rudolph, and I have not mentioned it at all in any of the posts.
So for all those of you using your red light Eliza, think adding a Rudolph to your red light armamentarium.
The photo shows the first Rudolph. The brand name is Bionase, but I’ve just done a quick search on various websites and you can buy exactly the the same device under different brand names. The prices vary considerably, so do look around before buying. (I paid $A8 for the one in the photo.)
I do recommend that you use Rudolph in a private spot at home. Observers of Rudolph-in-action cannot help making a comment about your nose and I can guarantee it won’t be complimentary…