422 replies to this topic

[srd]

I am starting A new thread on tDCS which is transcranial Direct current Stimulation.

I will be adding studies on tDCS.

1.tDCS during sleep improves memory
http://socyberty.com...arative-memory/

[bdoris]

I am starting A new thread on tDCS which is transcranial Direct current Stimulation.

I will be adding studies on tDCS.

1.tDCS during sleep improves memory
http://socyberty.com...arative-memory/

Left lateralizing transcranial direct current stimulation improves reading efficiency
Transcranial direct current stimulation over Broca's region improves phonemic and semantic fluency in healthy individuals

There's a lot of research on it. I recommend reading this review:

Electrified minds: transcranial direct current stimulation (tDCS) and galvanic vestibular stimulation (GVS) as methods of non-invasive brain stimulation in neuropsychology--a review of current data and future implications.

TDCS is great but TMS is better! The main issue is that you need a really good understanding of the brain if you want it to be effective. And a good MRI of your head. That is, if you do it yourself which I strongly disagree. Also, I advice you not to make a DIY device - a battery and two wires is the best way to damage your brain. Even if in theory it looks sounds, in practice it' not the case.

The lack of accuracy is a big downside, the fact that you need to have both cathodal and anodal stimulation at the same time is a another big downside - and your shoulder isn't the best way to avoid this issue. And finally, TDCS/TMS is best used in conjunction with other exercises - otherwise it's effectiveness is vastly reduced.

An anecdote: the lateralization of functions in my brain is completely screwed up, especially concerning language areas. I learned empirically that when I got a completely different effect from stimulating language areas - I've become a super spell checker / grammar checker for an hour. Understanding went down, but I could spot any mistake in style, grammar or spelling unlike any other time - because it was mentally painful to spot one. Luckily, it's not permanent =P

I'll be soon working with a real TMS device so I'll be able to test a few theories so I'm going to have some real fun this coming months.

Edited by bdoris, 03 July 2011 - 10:57 AM.

[IanA87]

How did you get access to the device? Where are you? If you're close enough I want you to experiment on me :P

[srd]

I have my own tDCS device. It works for me but it is very inconvenient to apply everyday.

[IanA87]

"It works for you" how? What exactly is it improving for you? How have you measured these improvements? Where did you purchase the device and how much was it?

[bdoris]

"It works for you" how? What exactly is it improving for you? How have you measured these improvements? Where did you purchase the device and how much was it?

A real medical TDCS device would cost you 3,000 euros. A iontophoresis device would be cheaper - between 200 to 300 euros, but you'd have to tweak it and be sure to buy a DC one, not an AC. A TMS device would cost 30,000 euros.

You can buy an iontophoresis device on the internet easily, the other two have to be purchased through your institution or you'd need to be a medical doctor.

I haven't used it frequently - tried a few times for experimenting purposes - therapeutically it won't do much due to its disadvantages. Simply changing the membrane potential of a large zone of neurons isn't making necessarily improvements. It can help in some cases - major depression for example - or nicotine dependance - but for "enhancement" uses it is much less practical. All the clinical trials were made on older subjects or people with pathologies - on a healthy adult brain there will be much less improvements.

[srd]

2. tDCS effects on working memory
http://socyberty.com...working-memory/

[srd]

I am Research Worker and with the help of an engineer I managed to build my tDCS device. It would cost around 250$. You have to put tDCS every day for 20 mins. Anode on left dorsolateral prefrontal cortex and cathode on right supraorbital region. The device runs on 9V battery.

[srd]

I am Research Worker and with the help of an engineer I managed to build my tDCS device. It would cost around 250$. You have to put tDCS every day for 20 mins. Anode on left dorsolateral prefrontal cortex and cathode on right supraorbital region. The device runs on 9V battery.

[Ben]

I am Research Worker and with the help of an engineer I managed to build my tDCS device. It would cost around 250$. You have to put tDCS every day for 20 mins. Anode on left dorsolateral prefrontal cortex and cathode on right supraorbital region. The device runs on 9V battery.

Hi there, just wondering if you have the schematics for this device. Also, have you used it yourself? Notice anything interesting?

Kind regards,

Ben.

[Krell]

Zap your brain into the zone: Fast track to pure focus

http://www.newscient...cus.html?page=1

[zeroskater6979]

for such an old technology it really does some great things on the cognitive enhancement front. wonder if there are any studies being conducted that we could participate. its funny, tDCS seems so promising that adventurous people are making their own devices. i'd rather buy a professionally made device, and wouldn't be afraid to experiment on myself, so long as an experienced person guided me in the right direction. very interesting.

[SucubbusLT]

Zap your brain into the zone: Fast track to pure focus

http://www.newscient...cus.html?page=1

This is really interesting. I am thinking of building one myself.

[Nootr]

Does anyone know how to make suitable electrodes to avoid skin burning and irritation or have any schemes of such devices?

[SucubbusLT]

Does anyone know how to make suitable electrodes to avoid skin burning and irritation or have any schemes of such devices?

There is link for schema: http://brmlab.cz/pro...in_hacking/tdcs
It uses beercan foil and soaked sponges with salty water

[zeroskater6979]

i dont trust it, i dont trust any dyi devices or experiments, and i can't even interpret the data the guy posted, its complete nonsense. it's a shame there aren't any consumer versions that the public can buy. i think there have been enough studies demonstrating its safety and efficacy.

[Nootr]

I am not good in electronics. What for does he use current regulator? His scheme is not understandable as well as how he made the electrodes. Did he attach sponges to the foil cut from beer can? Also I do not understand why he adds a test lamp to the scheme. The new battery will work for some time and he can later measure the current with a digital multimeter or by attaching the lamp from an old pocket lantern.
Also it is strange that he attached electrodes to the piece of cloth. If they are not detachable from it, he cannot use electrodes on other areas of head where the distance between electrodes is larger or smaller. He presents only one way of application of electrodes to head. Are there any other ways? Who has already tried tDCS? Any experiences?
IS it possible to use nickel-magnesium rechargeable battery instead of the alkaline one?

[Nootr]

Maybe we will not see a commercial device soon because if we have it, the large industry of antidepressants will become bankrupt. So why no use diy-made device?

[zeroskater6979]

i don't think they could possibly go bankrupt because of a tdcs consumer device. if anything it would be used as an adjunct to antidepressants or for MDD patients that don't respond to drugs. I do think you're right in assuming that it would be marketed as a therapy for depression but it's probably going to be used for cognitive enhancement mostly and stroke recovery and things like that. The FDA has already approved it and we all know they're in bed with Big Pharma.

[SucubbusLT]

I am not good in electronics. What for does he use current regulator? His scheme is not understandable as well as how he made the electrodes. Did he attach sponges to the foil cut from beer can? Also I do not understand why he adds a test lamp to the scheme. The new battery will work for some time and he can later measure the current with a digital multimeter or by attaching the lamp from an old pocket lantern.
Also it is strange that he attached electrodes to the piece of cloth. If they are not detachable from it, he cannot use electrodes on other areas of head where the distance between electrodes is larger or smaller. He presents only one way of application of electrodes to head. Are there any other ways? Who has already tried tDCS? Any experiences?
IS it possible to use nickel-magnesium rechargeable battery instead of the alkaline one?

- current regulator is recommended to add, because current from the battery tends to deviate which could affect the performance. I have tried with beercan foil but it was covered with something which didn't let electricity trough, so i just used tinfoil. Test lamp i think is not necessary at all.

[Nootr]

- current regulator is recommended to add, because current from the battery tends to deviate which could affect the performance. I have tried with beercan foil but it was covered with something which didn't let electricity trough, so i just used tinfoil. Test lamp i think is not necessary at all.

Which voltage should be used? The scheme mentioned here shows some resistors and a current regulator? Don't resisters low down the voltage? I thought that the voltage should be 9 volts and 1 ma strength.
Could you describe your experience with this method of brain stimulation? Did it work for you? What were the results?

[SucubbusLT]

I am still experimenting with that and can't say anything yet. I know little about electronics, but I guess resistors are needed to make it 1mA. Here is more: http://forum.allabou...ead.php?t=63037 and here: http://www.pearltree...1&N-f=1_2107261

[trismatic]

- current regulator is recommended to add, because current from the battery tends to deviate which could affect the performance. I have tried with beercan foil but it was covered with something which didn't let electricity trough, so i just used tinfoil. Test lamp i think is not necessary at all.

Which voltage should be used? The scheme mentioned here shows some resistors and a current regulator? Don't resisters low down the voltage? I thought that the voltage should be 9 volts and 1 ma strength.
Could you describe your experience with this method of brain stimulation? Did it work for you? What were the results?

The 1k2 (1200) and 51 ohm resistors are indeed placed to regulate the current to 1mA. You can see the equation in the schematic. R1 = 1.25V/Ireq => 1.25V/0.001A equals 1250 ohms. Resistors are connected in series, so the true value is 1251 ohms.

[Nootr]

I followed the link and found this concerning the scheme in question:

"I frankly don't know how much current you will get. The resistance between OUT and ADJ is way out of specifications. I've never tried going that far beyond the specifications.

The box on the left is an excerpt from the datasheet.

While R1 = ~1.25/Ireq; they omitted that 10mA <= Ireq <= 1.5A, so 0.8333 Ohms <= R1 <= 125 Ohms. They are using 1251 Ohms, or more than 10 times the maximum allowed."

According to this post the scheme should give 10 mA and not 1 mA!

[zeroskater6979]

that is why you shouldnt diy unless you are actually experienced with electronics.

[Krell]

Where am I going wrong in my calculations below?

Take a voltmeter and set it on resistance (Ohms), put salty water on your fingers, and then hold the tips of the two probes in the wet finger tips of each hand.

What do you read?

When I do this experiment, my meter reads a resistance of about one hundred thousand (100,000) ohms +/- 100%.
That seems to be a typical resistance across any two points on the human body.

So if you want to create a current across two points on your body, then you can use Ohms Law to find out how much voltage to use:

V(volts) = I(amps) * R(ohms)

R = 100,000 ohms
I = 2 milliamps = 0.002 amps (according to my reading of the tDCS literature)

Solving:

V = 100,000 * 0.002 = 200 volts

(Better check my math)

So a 9 volt battery is not going to cut it.
You need the approximate voltage you get by sticking your fingers into house wall sockets, except as DC not AC.
Ohms Law says a 9 volt battery would produce only 9/100,000 = 0.00009 amps = 0.09 milliamps = 90 microamps
That is lower than the typical tDCS 2 milliamps by a factor of 2/0.09 = 22.22x

Looks like you will need a lot bigger battery!

Perhaps this higher voltage required explains why the the research systems are so expensive.
You want to be pretty careful when dealing with hundreds of volts and human bodies.
I guess electric chair makers found out long ago that they could not get by with battery power.

Edited by Krell, 15 February 2012 - 08:09 PM.

[Nootr]

The most simple way to do is just to measure voltage and amperage on tips of the professional equipment and to replicate it with the diy device. Am i wrong? Does anyone have access to such professional equipment?

[Nootr]

Some feedback http://health.groups...Stim/message/21

[longevitynow]

I got a tcdc machine from Canada, about $500. It works!! But I find build quality is mediocre and others with same device say the same thing.

[trismatic]

I followed the link and found this concerning the scheme in question:

"I frankly don't know how much current you will get. The resistance between OUT and ADJ is way out of specifications. I've never tried going that far beyond the specifications.

The box on the left is an excerpt from the datasheet.

While R1 = ~1.25/Ireq; they omitted that 10mA <= Ireq <= 1.5A, so 0.8333 Ohms <= R1 <= 125 Ohms. They are using 1251 Ohms, or more than 10 times the maximum allowed."

According to this post the scheme should give 10 mA and not 1 mA!

Yes, that is correct. You should use the LM317L version, which can go to 1mA or even 500uA. The normal LM317 can go lower than 10mA, but it's not going to be stable and as you said - the current can kinda be anything (well not anything, but different what you want :P).

...

I think I read somewhere that the professional stuff uses also low-voltage (9V). It's just 1mA regulated without the human head as a load. The internal synaptic voltages are very minimal, so I don't think you need a huge current to actually alter them. I think the more important factor is to have the perfect route.