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Author Topic: HELP PLEASE! 40hz light to restore gamma waves to the brain to fight Alzheimers  (Read 35913 times)

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I tested with 2 antiparallel blue leds running directly from my FG at 40Hz AC.
It seems to me that the flickering is less this way, but it could be the difference in used leds.

Anyway, here a short video of it:   https://www.youtube.com/watch?v=GBg-dsae5Bw

Itsu
   
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One of the other grad students in my department at UCSC was studying flicker. He claimed that with the right frequency and waveform he could make anyone do anything. I participated in some of the studies and I was able to detect flickering stimuli at up to 60 Hz. Oddly enough, the "critical flicker fusion frequency" actually goes _up_ when the subject is fatigued or on certain recreational drugs. (At the time I probably fit into both those categories...  :D   )  If you have two flickering sources Red and Green, and flicker them at the right frequencies, you will see Yellow. There are many interesting perceptual things that you can do with flicker.

https://en.wikipedia.org/wiki/Flicker_fusion_threshold

As far as effective brain stimulation goes, yes, you probably want a non-smoothed signal to the LEDs (no capacitors across the output). The Arduino Nano seems like a good way to get relatively precise timing. On the other hand, the brain and the visual system in particular are definitely "analog" (although the visual system uses a type of "pulse coding") and it may make sense to program the Arduino to produce a slightly varying frequency instead of a rock-steady 40Hz.

To tell if your LEDs are flickering without instruments you may be able to use "persistence of vision"; that is, move your eyeballs (or conversely the LEDs) rapidly from side to side. A flickering LED should produce a "trail" of dots, whereas a steady LED will just make a constant streak.  I have an electric clock that seems rock-steady when viewed directly on, but if I sweep my eyeballs I can easily see the trail of dots indicating a flicker at 60Hz. (USA mains frequency).

If you can see a mains-powered incandescent bulb flickering much, there is probably something wrong somewhere, as the filament of an incandescent bulb is its own "smoother" and really doesn't have time to cool down between cycles when it is getting an AC current at mains frequency.

 :o




   

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Buy me a cigar
Hi Itsu.

How about trying a 40 Hz triangular wave form direct on the LED's?

Just a thought.

Cheers Graham.


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Of course I do not know any details about the study concerning the 40 Hz light pulses.

But if I consider that the aim is to stimulate the brain, I would say that one wants 40 rather short light pulses per second. The onset of the light would do the stimulation and not the duration of the light.

So, the duty cycle of the 40 Hz pulses only needs to be long enough to bring the LEDs to full brightness in the shortest possible time and then the LEDs could be off, also as quickly as possible.

And the light pulses should be annoying, otherwise there would be no stimulation.

Just my ideas.

Greetings, Conrad

   

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Hi Itsu.

How about trying a 40 Hz triangular wave form direct on the LED's?

Just a thought.

Cheers Graham.

Graham,

using a triangular, square or sinusiodal AC waveform does not change the flickering much, it does affect the brightness as each waveform has its own rms value.

Itsu
   

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Ok here it is. I think the frequency is right 12.5ms on / off.
https://youtu.be/ZUWMZ44yVk4
   

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Jim,

the audio is a little low, but its looking good.
The flickering seems similar as mine at 40Hz (DC) which is indeed 12.5ms on, 12.5ms off (50% duty cycle).

Itsu
   

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Jim,

the audio is a little low, but its looking good.
The flickering seems similar as mine at 40Hz (DC) which is indeed 12.5ms on, 12.5ms off (50% duty cycle).

Itsu

Thanks Itsu, back to the shop today to get more LEDs . First time I've played with arduino. I have read that trying to drive multiple leds on one microcontroler could damage it. Is that correct. I was just going to hook them up in parallel and use a 9v batt to power it.
   
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... .-.. .. -.. . .-.
Hopefully this might help, with you going along the Arduino route.
It's my 555-A-Like circuit, developed for something else but maybe it could be useful for this.
https://www.youtube.com/watch?v=_Fh3G0Nk8xY
It features a 128x64 OLED screen (cheap and effective at approx $3.50) and 2 pots for Frequency and Duty Cycle.
It doesn't need the screen and will run without it.
1% to 95% duty, but at the moment only 1Hz to 12Hz because of the screen routine. I'm going to speed the thing up for 40Hz. Anyway, will add the code link to the vid description and the Fritzing breadboard circuit is below,
The thing being, that small adjustments in duty cycle might be part of this slight flicker situation too. A 60% duty cycle would flicker less than 50%, but in the description of how their system works Picower could still say it was on for half the time, off for half the time. If the optimal was 54%, that could easily be set too. Once all was known, set up and working, the pots could be removed and either resistors put in place or the code redone.

An Arduino's outputs can deliver 40mA, more than capable of driving a transistor...which means overcurrent will be no issue. Run anything via the transistor instead. 1K resistor from the output pin to the Base, Emitter to ground, Collector out to the load.

My wife's Dad passed away last November due to this and her mom is showing signs of a similar path. All of us might end up with the damn condition, so this research can be self centered for the future as well as helping those who have it now.
The glasses idea was marvellous ! which brings thoughts of a sleep cap for overnights.
Wasn't there something about flickering ping pong balls on the eyes at nights recently ?

Best wishes to you, your father and family Jim :)
 


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ʎɐqǝ from pɹɐoqʎǝʞ a ʎnq ɹǝʌǝu
   

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just trying to work out how to best attach the board to the hat now. I've put a pot in so I can adjust brightness.
   

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Hopefully this might help, with you going along the Arduino route.
It's my 555-A-Like circuit, developed for something else but maybe it could be useful for this.
https://www.youtube.com/watch?v=_Fh3G0Nk8xY
It features a 128x64 OLED screen (cheap and effective at approx $3.50) and 2 pots for Frequency and Duty Cycle.
It doesn't need the screen and will run without it.
1% to 95% duty, but at the moment only 1Hz to 12Hz because of the screen routine. I'm going to speed the thing up for 40Hz. Anyway, will add the code link to the vid description and the Fritzing breadboard circuit is below,
The thing being, that small adjustments in duty cycle might be part of this slight flicker situation too. A 60% duty cycle would flicker less than 50%, but in the description of how their system works Picower could still say it was on for half the time, off for half the time. If the optimal was 54%, that could easily be set too. Once all was known, set up and working, the pots could be removed and either resistors put in place or the code redone.

An Arduino's outputs can deliver 40mA, more than capable of driving a transistor...which means overcurrent will be no issue. Run anything via the transistor instead. 1K resistor from the output pin to the Base, Emitter to ground, Collector out to the load.

My wife's Dad passed away last November due to this and her mom is showing signs of a similar path. All of us might end up with the damn condition, so this research can be self centered for the future as well as helping those who have it now.
The glasses idea was marvellous ! which brings thoughts of a sleep cap for overnights.
Wasn't there something about flickering ping pong balls on the eyes at nights recently ?

Best wishes to you, your father and family Jim :)

Thanks mate. Good video and some awesome ideas. Mum was delivered the news today that he has to go into a nursing home. I'm now thinking of a battery operated lamp for his room. Would the addition of the transistor be enough to run some of those 50 led lamps. In the podcast the professor ends with her xmas tree lights are tuned to 40hz. I'd like every light in his room tuned to it.  All the best for your wife's mum. I'm sitting here testing the cap and it's bloody annoying.

The podcast does say white light when discussing the LEDs. I listened again today.
Thanks Wallace.
   

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One of the other grad students in my department at UCSC was studying flicker. He claimed that with the right frequency and waveform he could make anyone do anything. I participated in some of the studies and I was able to detect flickering stimuli at up to 60 Hz. Oddly enough, the "critical flicker fusion frequency" actually goes _up_ when the subject is fatigued or on certain recreational drugs. (At the time I probably fit into both those categories...  :D   )  If you have two flickering sources Red and Green, and flicker them at the right frequencies, you will see Yellow. There are many interesting perceptual things that you can do with flicker.

https://en.wikipedia.org/wiki/Flicker_fusion_threshold

As far as effective brain stimulation goes, yes, you probably want a non-smoothed signal to the LEDs (no capacitors across the output). The Arduino Nano seems like a good way to get relatively precise timing. On the other hand, the brain and the visual system in particular are definitely "analog" (although the visual system uses a type of "pulse coding") and it may make sense to program the Arduino to produce a slightly varying frequency instead of a rock-steady 40Hz.

To tell if your LEDs are flickering without instruments you may be able to use "persistence of vision"; that is, move your eyeballs (or conversely the LEDs) rapidly from side to side. A flickering LED should produce a "trail" of dots, whereas a steady LED will just make a constant streak.  I have an electric clock that seems rock-steady when viewed directly on, but if I sweep my eyeballs I can easily see the trail of dots indicating a flicker at 60Hz. (USA mains frequency).


If you can see a mains-powered incandescent bulb flickering much, there is probably something wrong somewhere, as the filament of an incandescent bulb is its own "smoother" and really doesn't have time to cool down between cycles when it is getting an AC current at mains frequency.

 :o


Thanks for the info and link TK.

indeed when moving my eyeballs rapidly from side to side over the 80Hz leds, i see only a constant streak, no dots, so 80Hz is to much for my eyes to persive any flickering.
So 40Hz it is, either AC (antiparallel leds) or DC.


Itsu
   

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Jim,

would an hour a day (like 4x 15 minutes or 2x half an hour spread over the day) not be enough?
I mean who want to stay in a room with this constant flickering going on.

A sturdy transistor or MOSFET would be able to drive a string of leds (series and parallel), not sure what you mean by " those 50 led lamps", they probably
have their own circuit to transform the 220 or 120V AC to whatever they use to drive those leds.


Itsu
   
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Ok here it is. I think the frequency is right 12.5ms on / off.
https://youtu.be/ZUWMZ44yVk4

May be it is only the video, but your LED hardly switches off. The flicker is not pronounced.

Try 5 ms on and 20 ms off. Or even 2 ms on and 23 ms off.

Greetings, Conrad
   
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JimBoot, i strongly encourage you to contact that doctor personally and discuss it with her.

I fly over research and i dont think is so simple. Brain is not computer, we still dont fully understand how it work. I think that frequency is not enough to make any difference, there must be some synchronization with brainwaves to get positive effect (if she done none that explain why just half of patients react in positive way).

Doctors like this should be interested in human test subjects, so if you will get in touch with her she should be interested in cooperation. Testing this on yourself or dad could be potential risk.

regards
   

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Good point and good advice   O0


Itsu
   
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yes,,
 been getting all the Ducks in a row for the Doctor visit
 O0
   
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... .-.. .. -.. . .-.
Would bet your Dad would be thrilled about being part of such a study...something very real that his son wants to do for him, using learned skills. That's never a bad thing.
I mean, I presume you have discussed rapidly flashing lights in his eyes with him Gromit ? LOL
"Just sit here while I get the wires and lights and sticky tape and bandsaw and plasma cutter and hammer"
 O0

Btw, have converted the code to use the Adafruit library for the OLED screen. It's still only stable to 14Hz  ???
It would seem that the screen hardware is setting that limit.
So...perhaps the frequency could be displayed ON the LED's !
(not really, but the idea appeals)


---------------------------
ʎɐqǝ from pɹɐoqʎǝʞ a ʎnq ɹǝʌǝu
   

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JimBoot, i strongly encourage you to contact that doctor personally and discuss it with her.

I fly over research and i dont think is so simple. Brain is not computer, we still dont fully understand how it work. I think that frequency is not enough to make any difference, there must be some synchronization with brainwaves to get positive effect (if she done none that explain why just half of patients react in positive way).

Doctors like this should be interested in human test subjects, so if you will get in touch with her she should be interested in cooperation. Testing this on yourself or dad could be potential risk.

regards
Have you listened to the podcast? The professor would disagree with you. Her xmas tree lights are at 40hz. Thanks for your concern. I have tweeted to the institute and the professor.
   

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Jim,

would an hour a day (like 4x 15 minutes or 2x half an hour spread over the day) not be enough?
I mean who want to stay in a room with this constant flickering going on.

A sturdy transistor or MOSFET would be able to drive a string of leds (series and parallel), not sure what you mean by " those 50 led lamps", they probably
have their own circuit to transform the 220 or 120V AC to whatever they use to drive those leds.


Itsu
Sorry itsu, yeah that was a little vague sorry! Was trying to get an idea of the upper limit of the number of LEDs I'll have a tinker today.
   

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Would bet your Dad would be thrilled about being part of such a study...something very real that his son wants to do for him, using learned skills. That's never a bad thing.
I mean, I presume you have discussed rapidly flashing lights in his eyes with him Gromit ? LOL
"Just sit here while I get the wires and lights and sticky tape and bandsaw and plasma cutter and hammer"
 O0

Btw, have converted the code to use the Adafruit library for the OLED screen. It's still only stable to 14Hz  ???
It would seem that the screen hardware is setting that limit.
So...perhaps the frequency could be displayed ON the LED's !
(not really, but the idea appeals)

Dad thinks he's a fire truck. Well not quite but no, we won't be having that conversation. :) bit too late for that.
   

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Have you listened to the podcast? The professor would disagree with you. Her xmas tree lights are at 40hz. Thanks for your concern. I have tweeted to the institute and the professor.


Jim,

what do you mean by podcast?   I see a video in the link on your first post,  is that what you mean?   No mention there of a xmas tree though.


Itsu
   

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May be it is only the video, but your LED hardly switches off. The flicker is not pronounced.

Try 5 ms on and 20 ms off. Or even 2 ms on and 23 ms off.

Greetings, Conrad
Hi Conrad, I've been looking at the the gamma brainwave patterns and as Tk pointed out they are certainly not in anyway a constant 40hz. Thanks for the suggestion.
   

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Jim,

what do you mean by podcast?   I see a video in the link on your first post,  is that what you mean?   No mention there of a xmas tree though.


Itsu
Sorry itsu this is the podcast where the news was announced last week. http://www.radiolab.org/story/bringing-gamma-back/
   

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Thanks Jim,

a kind of chaotic podcast, but indeed she was talking in the end about "OED lights", so pointing to these new Oled lights.

http://www.photonics.com/Article.aspx?AID=35845

http://www.oled-lights.org/category/oled-lights/

Itsu
   
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