There have been a couple of papers [1] that can induce this process while awake using particular image patterns as confirmed in an MRI. I think the NIH confirmation is running behind in the science, independent research is quite a bit ahead of them. I came across the paper on this last year and implemented a very simple page with the parameters they used [2].
There is a number of disease models that show reduced or no glymphatic clearance and as such these people need treatments to clear out their brains and these image routines seem to help. A lot of people find this pattern extremely taxing to watch especially for the recommended number of cycles, you can feel the effect on the brain its hard to describe the sensation its a bit numbing and the image has the sensation of changing as the cycle runs like its a visual trick. You might get left feeling like you have been clubbed over the head the first time.
I find it interesting this is one aspect of disease research I am looking into and is related to Long Covid and ME/CFS.
Paul's animation wasn't playing at an even rate for me, for some reason, so I created two video versions (8Hz and 12Hz) with the 16 second on/off period, starting with an off period, running for 254 seconds, as per the paper. These versions end with an an additional off period, as a 'cool down' from the flicker.
Framerate of 24Hz differs from the 120Hz as presented in the paper, but here there is no 40Hz flicker attempt so it shouldn't be an issue.
Compression may affect the edges of the lines, but downloads are enabled.
I stared at the 8hz one, for the entire duration, and I feel a calm afterward, however I'm not sure if this is because I stopped doing/thinking for a few minutes with measured breathing or if it is me noticing the difference now that there's a lack of stimuli after the video ends.
What measurements or tests can I do to judge whether something is happening, or has happened after watching the videos?
Wow! So a visual effect similar to some psychadelic hallucinations is associated with brain cleaning!
Also, I've been at concerts where the light show guy seems to have reverse-engineered the filters our brains use to process raw signal into "images", and could use the lights to create just the raw primitives.
A few hours of that and it was like I was learning to see all over again, a tune-up/calibration of my visual system.
But only for the brains of people with severe or undertreated epilepsy of carefully selected varieties. You can trigger a potentially fatal seizure by showing them an appropriately stimulating image. Which likely was a known concept to the author of the story.
For the rest of us the negative feedback along the optical axis puts a stop to such shenanigans.
I'm interested to hear your reasons why you think it's closer to reality. I don't see why the discovery of the brain wastage system would help a brain crash from being possible.
Edit: Just looked back at the post and that it involves an image causing the glymphatic system to react.
It is well established that visual patterns affect brain activity, this is used in clinical practice by neurophysiologists, put on an EEG cap and then do checkerboards, check if the activity is normal.
Now the question is if this provocation and resulting CSF flow is actually beneficial. Do you spike activity and get a rebound attempt at waste clearing due to waste accumulation of the neural spike, or is this like a massage for the brain that gives you a invigorating CSF dump?
I suspect it might not be a health improving activity. (I also suspect that you can get even more CSF flowing if you spin yourself at 6G in a full body centrifuge and that this too would not be conductive to health)
I once worked in an IT department of a genetics laboratory, which consistently publishes high impact papers in journals like Science and Nature.
While I was there I got to see some of the R/Python/Java code that had been created for all kinds of studies that had taken place there. It was some of the worst code I have ever seen.
But I do agree, the complete methodology including the code should be shared.
Staring at the v0.3 produces an effect similar to something I'm able to do trigger manually on command. I've always had the feeling that I'm somehow triggering a "flow" in my brain, but I have no way to confirm what's actually going on. It's actually stronger when I trigger it manually, and it feels like it flows down my spine and eventually some weak signal reaches my extremities. (Maybe that means it's not CSF after all?) Oddly, I do feel like I can think more clearly afterward, but the brain is very bad at judging itself, so it's more likely to be an illusion than anything real. Anyone else able to manually trigger a feeling like this in their brains?
It's similar to the effect of being hit with big news (good or bad), and the "sinking" feeling that comes with it, becoming suddenly introspective and oddly calm under pressure.
At least to me, of course. I have no idea if others have that same reaction.
I'm interested in how you accomplish this. I can do something along the lines of that by getting myself heated. I actually get a hothead and a tingling comes up to my brain like it's passing in a channel. It could simply be a sensation rising within the brain though, without an actual transport of something.
I can focus better after but it doesn't clear my head, just use that frustration or anger to become determined.
The 40hz visual + auditory stimulation is showing to be surprisingly effective in mice and humans. [1]
When I first heard this, I thought the open-loop nature, and the fixed frequency across subjects sounded improbable, but I'm happy to be proven wrong.
We work in the neurotech/sleeptech space doing slow-wave enhancement which, it is believed, increases glymphatic activity [2]. Recent studies have looked at the promise of alzheimer's prevention [3].
Thanks so much for creating and sharing this! Could you point me to any other independent research in this area? Also, as I read related journal articles, I'm trying to understand if the 40Hz sound is binaural (with a 40Hz difference between frequencies in each ear) or a straight 40Hz pulse (same in both ears). It's surprisingly hard for me to get a clear answer. Do you happen to have any experience with this or suggestions for related resources that might contain the answer? Thanks!
Why do you assume you're supposed to feel an immediate effect?
Increased CSF flow aids in clearing metabolic waste, distributing nutrients, and reduced oxidative stress. You'll feel none of this after a 3 minute session.
Its very much experimental so we don't know if there are people for whom this has no impact, all the people in the studies respond so the question is whether your cerebral spinal fluid is being pumped around and flushing your brain and you don't feel an impact or whether you get no cerebral spine fluid movement at all. Someone would need to recreate this experiment with you in the MRI to find out which it is.
I wonder how this will work with hypophantic and aphantic individuals (people with little to no "mind's eye" visual imagery), such as myself. Like would the effect still be registered the same as anyone else, or would it cause the imagery effect to lessen or be ineffective altogether?
I work in this field —- You’re mis-construing the research a bit. Your reference talks about CSF flow on a more macroscopic scale (clearance out the fourth ventricle), which is fundamentally different than the glymphatic system referenced in the original story.
From the paper, it seems like that the blood flow changes and the seizures are both caused by the increased processing load in the visual cortex; with the seizures also resulting from some faulty wiring in localizing that increased load to only the visual cortex.
So, more like A->B and A->C instead of A->B->C.
But I'd bet this visual stimuli is even more effective at causing seizures in vulnerable people than an unfortunate pokemon episode.
I’d like to see if anyone with Fatal Familial Insomnia has been treated with this pattern. I expected that insomnia stops this glymphatic clearance, and that’s what eventually kills them.
Wow, that is wild. I never would have thought that simply watching images would trigger something in the lymphatic system. This could have huge implications for multiple diseases.
It's taken 12 years to get from "this stuff exists in mice" to "we now know it actually exists in humans and is not vestigial". That seems like a long time. People get brain MRIs with contrast all the time, is there any reason why this never showed up? Because no one was looking? Or because it's a slow mechanism?
Looking up “brain MRI with contrast”, the biggest difference seems to be that in a regular MRI the contrast goes to the blood, but here it goes straight to the brain cerebrospinal fluid. You need open brain for that, so indeed doesn’t seem trivial.
Cerebrospinal fluid is produced in the brain, I would imagine that the contrast would end up in newly produced fluid as well, but maybe that assumption is wrong.
1. Blood brain barrier and CSF should be separate for all but tiny molecules. It's why CT angiograms are able to visualize distinct vessels. So it is pretty hard to directly interact with this sort of thing in vivo
2. A good chunk of the neuro community have been operating under the assumption that some of those mouse model findings are mechanisms in humans too. Since we couldn't easily prove it, people used a bunch of next best tools with fancy imaging that demonstrated it was very likely. On top of furter proof, this sort of study allows us to begin pinpointing exactly how close our next best tools are at estimating in vivo processes without opening up the head.
They injected a dye into the cerebrospinal fluid to confirm the pattern of diffusion into the brain.
I imagine this procedure would have to be confirmed safe in humans first. Also they needed subjects who already happened to be undergoing a specific type of brain surgery.
Its because we don’t normally inject Gad in CSF. Its kind of wild west to even do so, and these researchers were able to identify this unique dataset and ask some interesting questions.
“Other studies have suggested that the glymphatic system may be most active during sleep.”
Not only that but also the right sleeping position is relevant here. I don’t recall the scientist but he studied primates and their natural sleeping position, exactly this position also opens up the channels for the cerebrospinal fluid to flush the accumulated brain waste.
Interesting - whats the frequency - response hypothesis? I don't think you would want to do lymphatic drainage everyday unless you had a problem with your system (?)
Or the brain is high complex organ and full of MANY known and unknown functions which meet a specific or general need. Don't forget, it took us 100k years as human to get here, our current understanding of brain. you're being a little harsh here.
Readit News
There is a number of disease models that show reduced or no glymphatic clearance and as such these people need treatments to clear out their brains and these image routines seem to help. A lot of people find this pattern extremely taxing to watch especially for the recommended number of cycles, you can feel the effect on the brain its hard to describe the sensation its a bit numbing and the image has the sensation of changing as the cycle runs like its a visual trick. You might get left feeling like you have been clubbed over the head the first time.
I find it interesting this is one aspect of disease research I am looking into and is related to Long Covid and ME/CFS.
[1] https://journals.plos.org/plosbiology/article?id=10.1371/jou...
[2] https://www.paulkeeble.co.uk/posts/cff/
Framerate of 24Hz differs from the 120Hz as presented in the paper, but here there is no 40Hz flicker attempt so it shouldn't be an issue.
Compression may affect the edges of the lines, but downloads are enabled.
8Hz version - https://vimeo.com/1023278230/8ad6db6234
12Hz version - https://vimeo.com/1023275135/378186db55
What measurements or tests can I do to judge whether something is happening, or has happened after watching the videos?
Makes me think of Neal Stephenson's Snow Crash where a datafile can be a narcotic or mind virus. Maybe that's not such a crazy idea?
Also, I've been at concerts where the light show guy seems to have reverse-engineered the filters our brains use to process raw signal into "images", and could use the lights to create just the raw primitives.
A few hours of that and it was like I was learning to see all over again, a tune-up/calibration of my visual system.
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Dead Comment
But only for the brains of people with severe or undertreated epilepsy of carefully selected varieties. You can trigger a potentially fatal seizure by showing them an appropriately stimulating image. Which likely was a known concept to the author of the story.
For the rest of us the negative feedback along the optical axis puts a stop to such shenanigans.
Deleted Comment
Now the question is if this provocation and resulting CSF flow is actually beneficial. Do you spike activity and get a rebound attempt at waste clearing due to waste accumulation of the neural spike, or is this like a massage for the brain that gives you a invigorating CSF dump?
I suspect it might not be a health improving activity. (I also suspect that you can get even more CSF flowing if you spin yourself at 6G in a full body centrifuge and that this too would not be conductive to health)
> Psychophysics Toolbox Version 3 (PTB-3) is a free set of Matlab and GNU Octave functions for vision and neuroscience research
Scientists almost never want to share their code and it makes me sad. Why wouldn't they want to make their paper more easily reproducible?
I once worked in an IT department of a genetics laboratory, which consistently publishes high impact papers in journals like Science and Nature.
While I was there I got to see some of the R/Python/Java code that had been created for all kinds of studies that had taken place there. It was some of the worst code I have ever seen.
But I do agree, the complete methodology including the code should be shared.
It's similar to the effect of being hit with big news (good or bad), and the "sinking" feeling that comes with it, becoming suddenly introspective and oddly calm under pressure.
At least to me, of course. I have no idea if others have that same reaction.
I can focus better after but it doesn't clear my head, just use that frustration or anger to become determined.
What I also noticed were the after image effects. A strong blue dot every time it flashed and circles divided into 8 sections like a star.
This was trippy.
We work in the neurotech/sleeptech space doing slow-wave enhancement which, it is believed, increases glymphatic activity [2]. Recent studies have looked at the promise of alzheimer's prevention [3].
More links to research papers are on our website https://affectablesleep.com/science
[1] - https://www.nature.com/articles/s41586-024-07132-6 [2] - https://www.frontiersin.org/journals/neuroscience/articles/1... [3] - https://pmc.ncbi.nlm.nih.gov/articles/PMC10758173/
Being able to set a max duration would be neat, in case it's unsafe to lose track of time and let the pattern run for too long?
Classic outdated comment BTW ;)
Am I an outlier?
Increased CSF flow aids in clearing metabolic waste, distributing nutrients, and reduced oxidative stress. You'll feel none of this after a 3 minute session.
A lot of the reactions here reek of placebo.
Curious, could seizures caused by strobe light be related to the effects of draining of this fluid?
It certainly feels quite strange after watching the prototype for 8 cycles.
javascript:document.documentElement.webkitRequestFullScreen();
This is the closest I've ever felt to being a Borg.
1. Blood brain barrier and CSF should be separate for all but tiny molecules. It's why CT angiograms are able to visualize distinct vessels. So it is pretty hard to directly interact with this sort of thing in vivo
2. A good chunk of the neuro community have been operating under the assumption that some of those mouse model findings are mechanisms in humans too. Since we couldn't easily prove it, people used a bunch of next best tools with fancy imaging that demonstrated it was very likely. On top of furter proof, this sort of study allows us to begin pinpointing exactly how close our next best tools are at estimating in vivo processes without opening up the head.
I imagine this procedure would have to be confirmed safe in humans first. Also they needed subjects who already happened to be undergoing a specific type of brain surgery.
Not only that but also the right sleeping position is relevant here. I don’t recall the scientist but he studied primates and their natural sleeping position, exactly this position also opens up the channels for the cerebrospinal fluid to flush the accumulated brain waste.
https://pmc.ncbi.nlm.nih.gov/articles/PMC7698404/ Section 3.4.3
Dead Comment