Alzheimer's treatment with light.
posted: Oct. 15, 2022.
FLASHING LIGHT THERAPY FOR ALZHEIMER’S DISEASE
A non-invasive therapy that just might outperform drugs
Suppose you were diagnosed with Alzheimer’s and were battling with some of the symptoms that are associated with that disease; problems with memory, declining cognitive acuity, etc. Would you try an experimental treatment that preliminary tests indicate helps to improve memory and cognitive function in most cases? If this treatment is based in rigorous scientific investigation, is not a drug, is totally safe, non-invasive, and has no side effects; would that effect your decision? Flashing light therapy just might be that treatment.
SHOP ALTERNATIVE THERAPY FOR DEMENTIA
Some recent medical discoveries are pointing toward possible treatments like that described above; safe, non-invasive, etc. Research suggests that our body’s immune system can fight the effects of Alzheimer’s disease if they are working properly. Unfortunately, AD causes damage to many parts of the immune system. In fact, amyloid is now thought to be part of the ancient immune system; the amyloid plaques that build up in the Alzheimer’s brain result from a breakdown of that system.
There is a research-based treatment (not a cure) available for testing now that uses light to invigorate our natural immune system. Preliminary trials are encouraging; test subjects have demonstrated a 70% improvement in standardized cognitive assessments in just seven days. And there is evidence that treatment slows or even stops disease progression.
This is not bright light therapy
We have recommended and sold a different type of therapy light for many years. Bright light therapy employs a strong, full spectrum light to influence the circadian rhythms that control our wake-sleep cycle and can alleviate sleep disorders caused by dementia. This new therapy uses a flashing light to initiate a very different mechanism in the brain and produce a much more dramatic result.
People I talk to are generally skeptical by this point in a conversation, and I understand. I expect you to be as well; but before you dismiss this treatment as charlatanism, please read the scientific foundation on which it is based. It is a lot to ask of you to believe that a light can effectively treat Alzheimer’s disease, especially after the failures of so many drugs that have taken billions of dollars to develop. I won’t ask that of you. Not until I have provided some background.
Research teams at the brain and cognitive laboratories at MIT recently found a 50% reduction in amyloid plaques after just one hour of exposure to flashing light. The test subjects were transgenic mice∗ that were in early stage Alzheimer’s. Even though the subjects were mice†, these results are impressive.
On my desk now is a device that is designed around the principle used in the mouse experiments, but it is being tested to determine if human brains will react the same as do mouse brains. So far the human brain appears to react similarly to the way the mouse brain responded to the flashing light therapy.
∗ Transgenic mice are genetically engineered to model Alzheimer’s disease.
† Aside from the more obvious reasons, medical researchers use mice in their research because rodents’ “genetic, biological and behavior characteristics closely resemble those of humans, and many symptoms of human conditions can be replicated in mice and rats.” (LifeSciences) Inferences made about humans based on mice studies are more accurate than you might expect. But the correlation is by no means perfect.
A New Understanding of Memory
Among other things, the experiments outlined here shine some light on the little understood process of memory. Memories, it seems, are not actually lost when forgotten. What is lost is access to the memory. Think of a secluded pool deep in the jungle, accessible by a single path cut through the forest. One morning you find the jungle has taken back the path; the trail is completely grown over and there is no indication that it was ever there. The pool still exists, but you can no longer get there. This in itself prompts some interesting considerations concerning our understanding of memory disorders including certain dementia. If memories are in fact like the pool, then creating a new neural path to a lost memory can recover that memory.
Now the Science Behind Flashing Light Therapy
In a post of 24 Mar 2016, We May Be Able to Find Memories Lost to Alzheimer’s, we touched on some research by Susumu Tonegawa, Tonegawa’s team at the Picower Institute at MIT, using a procedure called optogenetic stimulation, found that they could get mice to remember previously forgotten experiences.
To very briefly summarize, the experimental design used electric shock to create a fear response in transgenic mice. As expected, the lab-induced Alzheimer’s caused the mice to forget the experienced shock. They no longer exhibited a fear response when in the testing environment.
Now the scientists implemented an optogenetic procedure, aimed at cells in the hippocampus of these forgetful rodents. The hippocampus is the area in the brain responsible for memory, of turning experience into memories. With optogenetics the fear response returned! The mice remembered the training that Alzheimer’s had caused them to forget.
Like an explorer hacking a new path through the jungle, It seems that the optogenetic procedure acted like a trailblazer in the brains of these mice, creating a new path to the memory of the electric shock. If optogenetics can create a new neural connection to memories, it stands to reason that it might play a role in Alzheimer’s treatment. Unfortunately, the treatment is very invasive. It involves drilling a hole through the skull to introduce a virus that makes targeted brain cells photo-sensitive. A fiber optic probe is then inserted into the brain to administer stimulation to those cells. The FDA frowns on using such procedures on human subjects.
With optogenetics scientists control brain activity with light
A detailed account of optogenetics is beyond the scope of this article. The procedure involves introducing light sensitive proteins into specific neurons, then stimulating those nerve cells with light. In this way individual groups of neurons can be studied in a Optogenetics is an exiting addition to science’s tools for exploring and understanding the brain. In fact, a team at MIT’s McGovern Institute for Brain Research were able to create false memories in mice using this technique.x If you are interested you can get more detailed accounts of optogenetics from Scientific American and on Wikileaks.
Aware of this research, a team headed by Li-Huei Tsai∗ also at MIT’s Picower Institute for Learning and Memory wondered if light stimulation could be administered in a less invasive manner. Professor Tsai’s group put transgenic mice into a dance club for one hour. Well, it wasn’t really a club but a box with a strobe-like light flashing at 40 times per second.
Light entering through the eyes will stimulate the visual cortex rather than the hippocampus, but these investigators were not attempting to influence memory producing neurons, but what we commonly call brain waves.
What are Brain Waves?
Brain waves are rhythms caused when neurons fire in groups. This synchronous firing is how different parts of the brain communicate. Different brain states (sleep, meditative, excited, contemplative, etc.) are each associated with a frequency range measured in Hertz (cycles per second). Lower frequencies correspond to more relaxed brain states. Gamma waves are at the highest frequency (38 to 42 HZ) and are present during normal waking activity. They are associated with thinking, memory, attention, spatial navigation, etc. The speed of the flickering lights used in the study (40 Hz) was selected to induce gamma waves in the brains of these mice.
After just an hour in the box the researchers found that the test mice had significantly reduced levels of Alzheimer’s plaques (amyloid-β) than a test group that didn’t get to party. “If humans behave similarly to mice in response to this treatment, I would say the potential is just enormous, because it’s so non-invasive, and it’s so accessible,” said Li-Huei Tsai. In other words, this study could result in the inexpensive, non-invasive, non-pharmacological treatment that we alluded to at the beginning of this article.
But how does a blinking light eliminate the hallmark plaques from the Alzheimer’s brain?
Normal neurons and neurons containing tangles and surrounded by Amyloid plaques. These plaques and tangles, the hallmarks of Alzheimer’s disease, are the proteins that, stimulated by flashing light therapy, the newly-voracious microglia clear out. ~Image credit Bright Focus Foundation
It appears there is a connection between gamma waves and a cellular structure called microglia. Microglia are immune cells that act as the garbage collectors of the nervous system, removing debris and dead cells and helping to control inflammation. AD somehow causes these cells to become inactive or ineffective, unable to keep the brain tidy and operating normally. Microglia in this impotent state might be considered to be another hallmark of Alzheimer’s disease.
The light blinking at a rate of 40 times per second stimulates gamma waves in the visual cortex, which in turn somehow modifies or transforms the microglia into what Professor Tsai calls “an engulfing state”. Responding to the flashing light therapy the microglia do their job and clear the brain of the debris that is at least partly responsible for damaging neurons and causing the symptoms we associate with Alzheimer’s disease.
And the surprises just keep on coming. Another major hallmark of AD, the fibrillary tangles caused by misfolded tau protein disappeared as well, cleaned out by the now voracious microglia. Blood vessels in the brain enlarged to almost twice their previous size. Eight weeks of this treatment protected brain cells from dying and the team found that synaptic connections were being restored.
Perhaps the biggest surprise was the discovery that the effects of this seemingly simple treatment spread to other parts of the brain, including the hippocampus and the prefrontal cortex.
∗ We have met Professor Tsai before; she is the researcher who helped Alzheimer mice remember a maze by putting them in a stimulating environment. Read more at Can We Remember Lost Memories?
Is Flashing Light Therapy Too Good to be True?
Now that I have laid it out it seems too simple to be a real solution. But Tsai’s team continues to get some remarkable results in the lab with her mice, and we are seeing some equally remarkable results with flashing light therapy and human subjects.
What does this mean? In the short term, it looks like we can slow, maybe even stop the progression of Alzheimer’s disease. For how long we don’t know. But we are also witnessing a marked improvement in memory and cognitive ability in as little as a week in our human subjects with Alzheimer’s.
A preliminary study assessed 24 individuals with AD diagnoses using two standardized cognitive scales, the MoCA Cognitive Assessment Test, the Mini-Cog™ Cognitive Impairment Exam; and a Subject Specific Life History (SSLH) exam, before and after administration of flashing light therapy. Following just seven days of treatment, the conclusion of this study was that:
All subjects exhibited improvement of cognitive function as expressed by testing with an average improvement of 73.6% across all exams. 92% of subjects were described as “improved” by their family and or caregivers, inclusive of “mood, disposition, and engagement” as defined in administration of a post therapy interview.
You can read the abstract of this study below in Related Research.
In the mice studies the affects of AD, the buildup of amyloid plaques and the ensuing memory and cognitive issues, return quickly if the treatment is stopped. We need more data to know if this is true of human subjects as well, but it will likely be. I, for one, would prefer have this non-invasive treatment for one hour everyday than to live with a diminishing cognitive ability.