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Bringing Gamma Back

Thursday, December 08, 2016 - 05:00 AM

Brain cells called microglia (green) stained for lba1, a microglia marker (Photo Credit: Hannah Iaccarino, Anthony Martorell)
Today, a startling new discovery: prodding the brain with light, a group of scientists got an unexpected surprise -- they were able to turn back on a part of the brain that had been shut down by Alzheimer’s disease. This new science is not a cure, and is far from a treatment, but it’s a finding so … simple, you won’t be able to shake it. Come join us for a lab visit, where we’ll meet some mice, stare at some light, and come face-to-face with the mystery of memory. We can promise you: by the end, you’ll never think the same way about Christmas lights again.

This piece was reported by Molly Webster. It was produced by Annie McEwen, Matt Kielty, and Molly Webster, with help from Simon Adler.

Special thanks to Ed Boyden, Cognito Therapeutics, Brad Dickerson, Karen Duff, Zaven Khachaturian, Michael Lutz, Kevin M. Spencer, and Peter Uhlhaas.

Producer's note about the image:

Those neon green things in the image are microglia, the brain’s immune cells, or, as we describe them in our episode, the janitor cells of the brain. Straight from MIT’s research files, this image shows microglia who have gotten light stimulation therapy (one can only hope in the flicker room). You can see their many, super-long tentacles, which would be used to feel out anything that didn’t belong in the brain. And then they’d eat it!

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Anthony J. Martorell, Dheeraj S. Roy and Li-Huei Tsai


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Comments [59]

tara conway from usa

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Feb. 26 2018 06:36 AM
Hermes from BC, Canada

I live in Canada. Both of my parents have dementia and my brother has early onset AD. I am probably next regardless of being a lifelong learner and exercising. My comment is on how the State affects medicine. In Canada we have rather Big Brother attitude to public health - that we citizens can't be trusted to make up our own minds about whether we want to be potentially endangered by incomplete research (as well as having monopoly health insurance, a related issue - unlike Switzerland and Singapore there is no two tier, i.e. everyone gets the same standard and we have a shortage of doctors - I suspect the two are linked). Anyway, to the subject at hand... Some years ago I went to a UBC conference sponsored by the AD Society. There were a lot of words but no action. Six years later none of those drugs or therapies are available. I hear periodically of promising new (and old, i.e. near IR light) therapies, but instead we continue to use drugs, many of which have side effects. I remember my mother being put on a drug where the odds were equal between doing harm, doing good and doing nothing. I thin it's time we opened up the marketplace and respected the motto 'my body, myself' when it comes to medical treatments. Perhaps government does more harm than good in monopolizing and controlling scientific research and medical practice.

Feb. 05 2018 08:27 AM

Not sure if anybody is still reading these comments after over a year but I found the link to the first article talked about.

Jan. 30 2018 06:09 PM
steve from new york

this is pretty cool.

Dec. 20 2017 02:17 PM
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Nov. 30 2017 03:48 PM
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Oct. 28 2017 09:24 PM
Mysta Squiggle from Sydney, Australia

Can RadioLab please follow up to find out how the human trials are going? It has been six months since the publication of the study and a one hour session with the lights is delivered results within 24 hours with the mice so I don't know why it is taking so long to hear about the human trials.

Jun. 16 2017 06:50 AM
Marc Traeger from Arizona

Robert Krulwich, the phenomenon you experienced with your father at the Seder dinner is not unusual. I may have missed this in one of the messages if it has already been suggested, but I suggest you watch the documentary "Alive inside: A Story of Music & Memory" in which a man plays music to people with dementia, and they "come alive" and suddenly talk about memories that you could not coax out of them by asking.
As you are probably aware, some things, such as smells and music, have particularly strong connections to memory. Perhaps sounds and smells have a different pathway through that brain to that memory, or perhaps they are just particularly strong connections. (I bet some research has explored that).
I was a little surprised that neuroscientists assumed memories were always lost or gone in people with dementia. My assumption (based on basic knowledge learned and practiced as a country doctor - nothing like the detailed knowledge neuroscientists have, so I will generally defer to them) has always been that the memory may still be there but access to it has been lost. I would not be surprised, as neuroscientists believe according to your podcast, that some memories may be lost forever since brain atrophy and loss of brain cells occurs in dementia. Thanks for a very interesting podcast.

Apr. 12 2017 01:45 AM

Using flickering light to (try) to adjust brain frequencies has been around for a long time (though they obviously didn't know about the Alzheimers effect). I know these things have been around for a long time because, about 20 years ago, I bought a pair of opaque glasses that would flicker light onto your eyes at various frequencies. The device I bought would also play sounds at various frequencies, too - so that you'd get the effects of both light and sound. I still have them.

Mar. 10 2017 10:31 PM
Matt from Ann Arbor, MI

Really great coverage, and many of the criticisms are warranted concerning it being a single study, in animals, etc. However there's evidence that exogenous rhythms can produce endogenous rhythms—speaking very broadly—and that those endogenous rhythms are not limited to the sensory regions of the brain in charge of perception. Otherwise, how is it that a certain piece of music can give you chills? It's not as if the sound waves began at the speaker and ended in the cochlea.

If you're interested in trying this therapy, the easiest way to get LEDs to flicker at 40 Hz seems to be by modifying an LED dimmer from Amazon. Here's the tutorial:

Feb. 23 2017 09:48 PM
Michael from San Diego, CA

This is an interesting piece of science that is *completely* misrepresented in order to hype up its potential therapeutic value.

Flashing light by itself does nothing to non-visual brain regions. The only reason light has an effect on these mice is because their neurons were genetically modified to respond to light.

In semi-basic terms, a modified virus was used to deliver a light-sensitive ion channel to a specific region of the brain. When light is shone on this brain region, the light-sensitive channel causes cells that received the virus to activate. For more information on this technique, you can google "Optogenetics."

The light itself has no effect--don't go out and buy flashing lights for yourself! The effect is caused by activation of neurons, and light is simply the means by which this is achieved (in combination with the virus injection). The only exception is primary visual cortex, which IS affected by flashing light without the need for virus, but this brain region is barely affected by Alzheimer's disease. It's super cool that flashing light has this profound effect on visual cortex, but there's no therapy here.

So any therapy requires delivery of the light-sensitive ion channel via virus injection, which means this is not clinically feasible for a number of reasons:

1) Alzheimer's disease affects the entire cortex of the brain. Currently we can only treat small brain regions with this modified virus, and this in itself is very invasive--it requires drilling a hole in the skull and injecting directly into the brain. So there is no way to deliver the light-sensitive ion channel to the entire cortex, and thus no way to use it to treat Alzheimer's.

2) Even if we could deliver the light-sensitive ion channel to the entire cortex, there is no way to activate it throughout the entire cortex without opening up the entire skull and shining light onto the brain. Anyone raising their hand to have their skull removed daily?

3) If we did have a way to deliver a gene to the entire cortex--we're working on it!--there are better therapeutic gene candidates that would not require light stimulation to activate. These include growth factors, neprilysin, anti-amyloid antibodies, and ApoE2.

In summary: this is cool science, but the therapeutic implications are completely fabricated. Given the number of people affected by Alzheimer's and looking for cures, this is just irresponsible. I hope that not many people wasted their money on flashing lights after hearing this episode.

Feb. 18 2017 09:15 PM

What role does this research have in understanding the cause and treatment of Alzheimer’s disease?

Feb. 16 2017 05:39 PM
Josh from Research Triangle Park, NC

I love the show and really appreciate all the hard work that must go into each podcast episode. However, I was disappointed with the "gee-whiz" science presented in this episode.

I would recommend reviewing your fellow WNYC programs Break News Consumer Handbook - Health News Edition from On The Media.

Bring Gamma Back violates a number of those suggestions - press release from a scientist with a bias, single source, hyperbolic descriptions, mice data only.

I appreciate your quote from the lead scientist at MIT regarding the abysmal failure rate of Alzheimer's therapies to date. I hope that flashing green light is the cure we've been searching for, but I wish the "we got a scoop" attitude had been tamped down in this episode.

Feb. 08 2017 06:12 PM
Karen Kraft from CA

I ordered the stuff to try this, will report back

Feb. 07 2017 09:36 PM
RC Crocitto

I made a DIY video on how to construct the light:

Feb. 07 2017 02:43 AM
Dave Siever from Edmonton, Alberta, Canada

This was a mouse study, so we can't say conclusively on the basis of this study that it will apply to humans, but fortunately, we have a study using SMR and beta frequencies of audio-visual stimulation that halted the Alzheimer's immediately and reversed it somewhat. Our devices now produce frequencies up to gamma, so all the basis are covered.

Dave Siever
Mind Alive Inc.

Jan. 17 2017 12:27 PM
Jennifer from NJ

Great episode. My dad passed away very recently. He cared for my mother, who has had Alzheimer's for many years. His sister also had Alzheimer's. We would like people to donate to Alzheimer's research in his memory. It sounds as though MIT is doing productive, smart research, and in a nice piece of synchronicity, my dad graduated from MIT himself. Does anyone know if the Picower Institute for Learning and Memory at MIT needs funding, or if it would be more effective to ask people to donate to a large fund, e.g. Cure Alzheimer's Fund or Alzheimer's Research & Prevention? Thanks so much.

Jan. 16 2017 02:15 PM
Vickie O'Sullivan from Boise Idaho

This is an exciting revelation that I couple in with music. The important word was BEAT.

I am an adult who cared for a father with 2 types of dementia. I now care for elderly women with dementia/s. One lady has been living with me for over 4 years. In these 4 years I have learned to keep a beat.

Observation 1) I've been leading a stretch yoga class 1 to 2 times per week at our local community center. I use the same routine and it is preferred I do not deviate from my constant routine. There are 4 people with dementia who have regularly attended this class and their caretakers insist I am the only instructor they like. It's not me, it's the fact that I use rhythm and repetition.

Observation 2) I keep my dementia residents lives organized with schedules, they trust the routine.

Observation 3) I have an alto voice and I read for residents for an hour nightly in the cozy mystery genre, keeping my voice in an even tempo. Although in her 7th month on Hospice, my present lady laughs at the humor and leans forward into the intrigue.

Observation 4) It has been a known fact that dementia patients respond to music. My present lady remembers and will sing with repeated songs.

Is there something about the energy in our brains responding to the beat?

Jan. 13 2017 12:12 PM
Leanne from Australia

How exciting is all the progress being made w Alzheimers in 2016.
Researchers in Australia in 2015 did a very similar project except using ultrasound.

Jan. 10 2017 08:53 PM
Rebecca from Atlanta GA

If light that flickers at 40hz could alter mouse brains in a beneficial way, could light at other rates of flicker cause damage to mouse (and possibly human) brains? Could one of the causes of Alzheimer's be related to exposure to (or lack of exposure to) certain kinds of light?

Jan. 10 2017 07:37 PM
dina from OH

A critical concept here that people are choosing to ignore, is the vast difference between a mouse brain and a human brain. Simply stated very little research on mouse brains can be generalized to human brains, or even rat brains! This is interesting research and exciting but not necessarily pertinent to human neuroscience. Perhaps they can duplicate their research on rats and then higher mammals. I have done mouse and rat research and one cannot necessarily be reproduced in the other. Calm down. This may be good for grant money for future research but dont potentially harm yourself assuming it will help humans.

Jan. 06 2017 03:36 AM
Rich Diman

Hey I made a version of this on youtube if any one wants to try it online.

heres the link

Jan. 05 2017 11:07 PM
Bryan White from Deep River, Canada

This research is encouraging. There is a publication that may be relevant to this topic. "Treatment of Alzheimer Disease With CT Scans: A Case Report" Jerry M. Cuttler1, Eugene R. Moore2, Victor D. Hosfeld3,and David L. Nadolski4
Ionizing radiation appears to have a similar effect. This paper does not identify any temporal modulation of the radiation intensity delivered by the CT scanner. As this seems to be important to the 'gamma' effect described, it may warrant further investigation.

Jan. 04 2017 03:40 PM
Miles Standish from Santa Cruz, Ca.

I may have missed this in other comments, but the podcast referred to an MIT study that was finally released through a periodical publication. What was the publication and when was it published? I would like to read the original source.

Jan. 03 2017 07:45 PM

Re the post from Joey from Australia on an existing device. It probably is good for what it is trying to do and It looked promising for replicating this protocol, but the gamma range that they use in the device is from 40 to 100hz. You cannot select a frequency of flicker within that range other than the mid point; their device will flash only the middle of the range or the whole range. The other DIY options may be the way to go.

Dec. 29 2016 04:32 PM
JW from NY

Looks like someone's actually made an app for the Vive VR set to implement the therapy in this episode.

Dec. 29 2016 09:49 AM
Debra Savelle from eugene, oregon

So I just wanted to send along this link in response to Robert Krulwich sharing about his father singing a passover song after a long period of not speaking. I would wonder also how music might be related to gamma

Dec. 24 2016 01:10 AM
Tom Wieland from Bishopville, MD

Very interesting story. Two questions or points occured to me. One, what frequency do our LED lights work at? I wonder if this influences any of our brain activity. Number two, another avenue to the brain is the ear. And the Jewish song might have had a frequency that opened up an avenue. So, have they considered putting songs or a beat out at 40 beats per second? Just curious.
Thanks for the show. Ta.

Dec. 20 2016 09:30 AM
Anthony Shaya from Florida

Wow, listened to this, amazing.
I'm sure other folks have considered this. But I think the broader implication, is that simply frequencies that we are exposed to, might potentially affect our health. If frequencies that are undetectable to the conscious mind in light, are affecting brainwaves that can have long term physiological effect on overall health of the organism. THAT IS AMAZING.
What about the fact that we are exposed to 60hz through light pretty much all day everyday? And how does sound affect this? Is this why music, or certain types of music has different appeals?
Think of how modern life could be affecting us in so many ways that are just being discovered. There are frequencies of lights and sounds everywhere that we are exposed to that we cannot detect consciously
I know a few years back there were these sound and light machines, that would pulse and beat at certain frequencies, I don't think they really caught on.
Presumably, light from the sun or fire, does not have any oscillation.

Dec. 19 2016 09:02 PM

So here's the problem: we can't just shine the 40 hz lights in our eyes and hope to get rid of Alzheimer's because the memory portions of the brain reside too far in back of the skull. With this said, how bright of a light would one need to permeate the skull? Is it possible? Please somebody who knows something answer this. Secondly, one commentator mentioned sound - is MIT experimenting with binaural beats at 40 hz? And maybe using it in tandem, or in float tank, our of pure curiosity? And thirdly - gamma is created in meditation. Since float tanks are meditation on steroids, then this seems like an interesting route as well.

Dec. 19 2016 07:15 PM
Jim Vandiver from Smithfield, VA at produces a long-lived LED light that I understand uses an oscillating circuit to pulse power to the light. An AA battery will run it 5 weeks. It's produced as a light source for places that lack electricity. I wonder if that circuit can be modified to produce the 40cps result used in this research. I've sent information to them about this episode, with a link, in case the idea has any merit and a result would be an inexpensive, long-lived source of 40cps lighting.

Dec. 18 2016 01:00 PM
Eva from Ohio

I love radiolab...and this last episode was great. It's been bugging me ever since though: if using light to stimulate the gamma frequency in the brain reduces beta-amyloid plaque in such significant measures, can the same reduction be achieved by simply giving the mice beta-inducing tasks? (Like having them figure out a maze or something)

Dec. 18 2016 09:04 AM

For anyone interested in creating a DIY version of this I created a working example of the flashing lights for under $50 using an Arduino Uno and a LED strip. The setup is very easy and code and instructions are available here:

Dec. 17 2016 09:14 PM
Mithrandir from San Jose

Hi Guys,

My full time job is making embedded systems and I can vouch that making a simple 40Hz LED light is something you can DIY. There are some caveats based on the intensity(nothing was mentioned in the podcast here) but it is mostly straightforward. If anyone is really interested, I can put up a simple circuit(you may need a teeny bit of soldering if you want to move the light around) with DIY parts for you to do this.

I don't doubt MITs work but... it almost seems too easy. For those of you who are curious, I ran into some trouble when interfacing light sensors due to tubelights. I expected them to hit a strong 60Hz but it turns out they strobe at 120Hz due to some rectification internally. Most of the time we are exposed to 120Hz light.

Another note on LED lighting. If designed well, LEDs will flicker nowhere near the visible spectrum(anywhere from 100s of Kilo Hz to 1 Mega Hz). LEDs work off DC supplies(current controlled if you want to be less cheap) and if the 60Hz AC line is rectified properly, the amount of 'flicker' is minimal. Of course if you get a cheap LED light, well, who knows.


Dec. 15 2016 07:38 PM
Robert OConnor from 41017

4k LED Tvs flicker at around 60 times a second. Since I watch my new LED tv for hours a day I will never get ALZHEIMERS but I will continue into the abyss of TV landitis and the smart people who do things like read and science will be more susceptible to ALZHEIMERS disease. God bless 4k television.

Dec. 14 2016 05:09 AM
Arturo Varela

In 1976 I was suffering from mental illness.i was hospitalized some years back. I heard voices. I couldn't difference reality from fiction. Some of the voices were so real that I could maintain long intelligent conversations with them. Others were very destructive and depressing. One night a different voice started talking to me. I noticed an accent in that voice that I never heard before. This voice wanted me to meet with me and wake me up at 2 in the morning. Asked me to go out to an empty parking lot. When I was there the voice with a sort of French accent asked me to look up to the sky. I felt wind coming from up there and I heard a whistling sound, all of a sudden a very powerful white light came from the sky directly to me eyes. I felt my whole brain illuminated. Next day a new world was open to me. The voices disappeared for good

Dec. 13 2016 08:49 PM
Andreas Kreutzer from Hurst, TX

I may have missed something (I was listening to this on my commute), but it seems to me there is a very important point that is not addressed in terms of the overall success of the treatment:

In the initial experiment, they modified cells in the hippocampus to be sensitive to light. The intervention increased microglia activity which in turn reduced beta-amyloid peptides in the hippocampus. In the follow-up, they introduced the light through the eyes and saw the same effect in the visual cortex.

So we have increased microglia activity seemingly localized to the area of the brain where the stimulus is introduced. How do we know this extends to the rest of the brain? The visual cortex obviously will respond to the visual stimulus, but how do we know this can be used to stimulate microglia activity in other areas of the brain?

Dec. 13 2016 03:04 PM
Matthew Woods from Massachusetts

LEDs don't "Dim" in the traditional sense. The flicker at lower frequencies as you dim them. Does anyone know the pulse frequency of the LED backlight on an iPhone (or other smartphone) at various brightnesses? If you could set your phone to the correct brightness (with a 40hz rate), you could then use a google cardboard or other vr headset as a therapy.

Dec. 13 2016 02:13 PM
Chris from San Francisco

We are all then living through a great experimental trial as we get AC driven LED lights in our homes, as they give us 60hz flicker. Wonder what will happen to us all in several years as they become more widespread. They annoy me now, but of course one of the benefits of LEDs is that they last forever, so it will be a while before I get to replace them.

Dec. 12 2016 11:19 AM
Mark Gearon from NSW, Australia

This is an interesting piece. I found there were many questions left unanswered which someone slightly more familiar with the content may have thought of. Before I start though I'll just state my understanding at present:
1. Beta-amyloid plaques are peptides which cause Alzheimer's Disease & are associated with some other neurodegenerative diseases. The plaques build up in the neuronal synapses over years, eventually blocking transmission of the action potential between neurons. When the neuron can no longer send or receive signals, it initiates apoptosis as it's no longer viable. Cells which have not yet committed apoptosis can become active again upon the removal of enough beta-amyloid plaque for it to receive & send action potentials. However once a cell is gone, it will never be replaced & its functionality is permanently lost.
2. The procedure discussed in the article resulted in a limited but very significant positive benefit to neurons in the stimulated regions.

So I guess my comments & questions are:
a) If you can't stimulate the microglial to achieve the Gamma frequency, the plaques stay active. So for example - even if you give every Alzheimer's sufferer glasses with LED's & fibre optics which point the light in through the pupil, you will only achieve Gamma frequency in the part of the brain which connects to the optic nerve. Given that the visual cortex - even the occipital lobe - while important, is not key in high order functions, would this light treatment be particularly useful even if it did work at least as well in humans as in the mouse model?
b) Why did the researchers opt to use light as the stimulus? It seems an extremely complicated way to activate certain regions of the brain. I admit, it would be outstanding in its accuracy, for apart from cells you specifically modified to be light sensitive, nothing else could be activated by the treatment. However once the initial principal was established, would it not have been worth trying a more general form of stimulation e.g repetitive transcranial magnetic stimulation (rTMS) or transcranial direct current stimulation (tDCS)? If the effects can be reproduced in any cells activated to 40 Hz then in theory a good many methods could be used to target anywhere in the brain.
c) I feel a more complete description of the pathophysiology of the disease & MOA of the treatment may have reduced the number of comments which, according to my stated understanding, fall out of scope for this study. It may also have put the findings in their proper, significantly more sobering light. I know the statistics of conversion from mouse model Alzheimer's treatments to human treatments was intended to convey this, but the limitations of the trial in terms of its treatment areas were seemingly not fully conveyed.

Thanks guys. I'd be happy to receive any corrections to my understanding of what are a great number of very detailed & not fully understood processes.

Dec. 12 2016 10:44 AM
Daniel Aronov from Australia

Thins episode is like the classic radiolab that I used to love. Please keep it science.

Dec. 12 2016 07:59 AM
Curtis from Rhode Island

To expand on previous comments:

In the modern world, we are surrounded by flickering light at 60hz (AC in the US), 50hz(AC in other places), 24 hz (TV), but not at 40hz. If 40hz improves brain hygiene, is it possible that other frequencies are detrimental? If the past generation is seeing a big increase in Alzheimer's, could it be that TV really does rot our brains?

And why, oh why, are we sitting our elderly dementia patients in front of "the tube" - 24hz - for hours, days, and years on end? Why don't we modify those TV's in nursing facilities to emit 40hz?

Dec. 12 2016 04:19 AM

WOW! This has to be the most important show you've ever done- one can build such a 40 cps strobe for $10 !!! Incredible- I've played a little with strobes- used to flash flashlights in eyes in the dark for the retention of image effect (note- do not do this). Man, though- I wish I knew this 16 years ago before my mother became an alien idiot. Caring for an Alzheimer's parent is the most horrible duty on the planet. You could probably make a cheap light socket adapter that could pulse lights at that frequency. Maybe nursing homes will be half emptied out by this discovery.

Dec. 11 2016 08:15 PM
Logan from Austin, TX

The iPhone app "Strobe light tachometer (RPM meter)" seems to be able to achieve 40hz strobe on iOS 9 or older.

Dec. 11 2016 02:29 PM
Ruth from Ca

Great so where do you find 40hz Christmas lights?
I understand that it probably won't work but I need to buy some lights anyhow...

Dec. 11 2016 12:59 PM
joey from australia
This guy has been doing it for a while.
Iv done it about 20 times its amazing its very psychedelic being under the light and honestly feel amazing after it. its very very strange but he is on to something. Listening to this podcast really backed my faith in this Light

Dec. 11 2016 12:13 PM
Logan from Austin, TX

In reference to my previous two comments: It seems like my iPhone's light can't exceed ~20hz. There are several strobe tachometer apps; I have tried two. It may be that they are older and mismatched with my software/hardware, and/or frequencies higher than ~20hz require an external flash device.

Dec. 11 2016 04:30 AM
Logan from Austin, TX

This is clarification for my earlier comment about the "StrobeLight" app for ios: The app can be found in the app store by searching "strobe light tachometer". You can enter 2400rpm into the settings for 40hz.

Dec. 10 2016 11:35 PM
Logan from Austin, TX

So, I found this app for ios called "StrobeLight". It has 1-130hz settings. I'm using it on an iPhone 5. I don't know how to test its accuracy, but it seems to work.

Dec. 10 2016 11:23 PM
FM from Singapore

Near the last 3rd quarter of the podcast. It sound like Music could be another research area which can help old timer. I am not a scientist, so I am unsure how sound convert to electrical signal in our brain. Science podcast does provide pleasant surprise frequently.

Dec. 10 2016 08:28 PM
Allen H from Bardeen Lived Here

I immediately thought of most office buildings 60Hz florescent lighting. I wonder if having it faster or slower actually has an adverse effect on mental processes? Perhaps it should be 40hz? [Although slower will just be more annoying.] How about 80Hz? Will appear more stable, but may cause similar excitation?

Dec. 09 2016 04:18 PM

Does anyone have instructions for building a 40 Hz LED strobe?

Dec. 09 2016 03:09 PM
C REC Mc from MA

Great Podcast! Appreciate learning about something I had no knowledge about. This piece is a fantastic flow of information that might only appeal to science or medical buffs. I was drawn into this piece and did not feel disconnected at any point. This made considering science and Alzheimers interesting - and not too congested with information that could go over a young persons head for instance. I will definitely use this piece with my young folks. Thank you! Media LAb @ NEPR

Dec. 09 2016 02:05 PM

What stops somebody starting clinical trials right away, in their own home... is not invasive or dangerous, and probably you can get all the parts from amazon...

Dec. 09 2016 10:08 AM
David Andres Leon from Copenhaguen, Denmark

Hi Radiolab,

I am a huge fan and follower of your podcast. This last episode reminded me of the so called "dream machine", as conceived by artist Bryon Gysin and William S. Burroughs in the late 60's. The machine is a stroboscopic flicker device that produces visual stimuli by strategically rotating a slit cylinder around a light source in such a way that it emits a light frequency of around 20Hz, thus stimulating the frequency of Alpha waves of the brain, inducing their spectator's mind into a relaxed mind state.

I find it fascinating that such device, initially conceived by the beat culture as an artistic artifact, could possibly be considered a precedent for such a potentially groundbreaking research as the one described in this episode.

Looking forward to the next story.


Dec. 09 2016 05:50 AM
Tim Wrate from Portland

Maybe going to the movie theaters each day would help. 24fps.

Dec. 08 2016 04:53 PM
JD Medina from San Francisco, CA

Guys, in your editing style of this particular episode you're not letting the scientists talk. You are not letting us hear it from their word of mouth! I can see an intention to adding value and insight by the hosts overlapping into what the scientists are saying, but it even looks disrespectful to the scientists and specialists to just interrupt their statements over and over again.

It's a shame because the subject and findings of the episode are extremely interesting!

Dec. 08 2016 12:53 PM
Ben from New Hampshire

Halfway through your show... There are several monoclonal antibodies that are either in clinical trials now or in the past that have successfully cleared beta-amyloid plaques from the brain yet failed to have any positive clinical outcome (return of memory, cognitive function, etc.). The going theory is that the plaques cause irreversible damage, and preventing them from forming in the first place (see "Tau hypothesis," among others) is the real clinical target.

Having listened to the entire show before posting this, you walked back your excitement surrounding plaque reduction. Yay for the accurate portrayal of facts. Now we need to tackle political discourse :)

Dec. 08 2016 12:27 PM
Brandon Terrill from Augusta, ME

The experiment described in the "Bringing Gamma Back" episode with mice and the room with the flashing LED lights reminded me of this article I read at

and this Youtube video of Steph Curry using "strobe light training":

NBA basketball players are also using strobe lights to train themselves, except how it is actually helping them is still hard to describe. They describe it helping their brains process the game on the court, helping them "slow the game down" and make decisions.

It seems as though there is a burgeoning field of research with strobe or flashing light and their effects on the brain. I would be fascinated to hear what your team could come up with if you look more deeply into this topic as perhaps an addendum to this podcast episode. This is all very fascinating.

Dec. 08 2016 11:53 AM

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