Here's the research standard. It shouldn't be beyond DIY.

soterixmedical.com/tdcs.php

And the simple circuit (now that I see that to post a link that isn't one just leave off the totally redundant HTTP: // www prefix.)

delabs-circuits.com/cirdir/theory/tutors/doc00009.html


Hey, Giorgio, I'm no Churchill but...

WARNINGS


While I find this a fascinating topic ALL CARE MUST BE TAKEN.

The level of current, regardless of voltage, that is deadly to us humans is around 30 mA. The better the connection the higher the current, like wet skin, tongue, strong pressure, damaged surface of skin, etc, so be very careful what you do.

Constant current is the best idea but if you want more safety add a voltage limit control to the connections to the skin so the voltage does not go above a set limit, like no more than 5 Volts as an example - just to be sure to be sure! This can be adjustable to take into account skin condition etc. I have no suggestion about any specific voltage but if 9 V is causing some problems a lower value would be wise. Use a Zener diode to control a set voltage, they are cheap and simple to use.

Making the Constant Current variable is easy too by adding a potentiometer to the circuit but make sure the maximum is well below the danger point as even 10 mA can cause damage to fragile tissues like nerve cells. Don't want to be a vegetable or go blind do you? Be Safe everyone.

And avoid using power packs etc in case of any mains voltage leakage, spikes etc. You only need one accident to to end it all. There's no second chances after that!

Hello all. I've been messing with my own tDCS rig a while now. In my case I went with the simplest option and used a 4.7K ohm resister on the 9volt. As I read the available material it seems the 2ma is "at the scalp". Therefore I took that to mean what the current would be if the electrodes were in direct contact with each other.

Of course the changing resistance of the skin makes a constant current regulator sound good. Otherwise a set-up like mine is likely to fall below effective current whenever the scalps resistance is too great. Still not quite a dead-man's switch but it's pretty much fail-safe as it is.

The one thing I really want to STRESS is the risk of heavy metal poisoning here. You do *not* want to use lead solder. Also use only lithium batteries. Otherwise you could get mercury, lead, nickel, cadmium, etc, etc. I saw a post that suggested the rate of heavy metal ion injection does not scale with voltage or wattage but with current. This means a tDCS rig with 1000+ times the current of a TENS device will push that much more into you. Maybe. And even TENS units generally come with lithium batteries.

Anyway I splurged for the $15 9volt at the ratshak. (So far I have yet to go insane.)

The full description of my device is the 9volt, connector, 4.7k ohm resistor, some TENS electrodes -I fit with sponges- connected by TENS unit leeds. So the plugs make it unnecessary to solder new electrodes on when the old ones wear out.

I don't use a switch or anything to avoid the usual tingle and other telltale effects. These let me know it's working so why 'fix' them? (Then I'd need a power indicator!)

Good luck, there are a ton of tDCS papers out there. Not many if any large scale studies though. Not yet, and too bad.

Disclaimer -I am not nor do I claim to be anyone you want to listen to or imitate.

Hi all,

Thanks for the warning gubins.

My two pence worth.

After doing my own research I suspect I might have ADD, which is an adult form of ADHD.

I'm lucky to have a job working as a teaching lab technician in a university. As a kid I loved the science classes, and that was one of the only times I'd pipe up and answer questions from the teacher. Eventually I dropped out of school in the 80's though. Got distracted and just floated down the wrong path and lost track of what was really important, education. Now I'm grown up (ha ha ha) and working in a Uni with students is fun, but I can't talk science with them. I kind of know what's happening in the practicals but I just can't help them with the work and I'm getting frustrated with myself.
With so many people out of work I'd never be able to get another job like this so I can't afford to lose this job and will do everything within my power to keep it......if only I could focus and keep my mind from wondering of the tasks/ jobs at hand. I'm so tired of being unfocused. It is, no pun intended, doing my head in .

After reading the article I realised that the state of 'Flow' they were talking about seems to help the brain stay on track. Sometimes when I'm playing a console game or a sport like badminton (hadn't played it since secondary/high school days) I can unconsciously slip into to that state of mind for a time. Yeah it feels like you're in the zone. Only problem is it doesn't last long and when I get that feeling I'm in the zone it evaporates. My feelings of Flow or "the zone" can't be replicated in other real world situations or when I'm looking at a text book. I suppose Flow is like your brain cutting out all the red tape, background noise, internal monologue and bureaucracy of learning and applying a new task.

Before I go to a shrink I'd like to try this tDCS just once to see if it can improve my state of mind before it's proven that I do have ADD and am put on a series of drugs or whatever.

Now can anyone point me in the direction of how to build a tDCS system from components bought and built from Maplins. I can solder no problem. I just don't know where to start. I'm looking for a safe system that will only work within the parameters of the suggested ranges of the Zap your brain into the zone article.

This might be the key to finally set people like me free of this disorder. I'm so tired of it.

Just had a thought that maybe one day we could buy a usb device, plug it into your laptop or tablet and switch on the Flow when you have to study or recharge your ability to stay focused.

Sorry If this post seems like I'm rambling on. Just giving you some background info on why I'd like to try it out.

I would like to add my voice to random e's and urge an open-source approach to this. I have Parkinson's disease and there is a sizeable contingent of volunteers looking at this and similar efforts as a way to encourage the rewiring of lost motor circuits. Given the low cost and relatively low profit potential, there is a danger of this, however promising, slipping away as other possible solutions have done. Work on the hardware and we'll provide the data.

Just a interesting abstract I found.

"Brain Res. 2012 Feb 23;1439:66-72. Epub 2011 Dec 29.
Oppositional transcranial direct current stimulation (tDCS) of parietal substrates of attention during encoding modulates episodic memory.
Jacobson L, Goren N, Lavidor M, Levy DA.
Source

Department of Psychology and Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel.
Abstract

Effective learning requires that attentional resources be focused on target information and withheld from irrelevant events in the learner's surroundings. This requires engagement of the brain substrates of selective attention and the concurrent disengagement of brain substrates of orienting toward changes in the environment. In the present study, we attempted to modulate activation of cortical substrates of attention during learning by physiological intervention, using transcranial direct current stimulation (tDCS). To effect adversarial modulation, we applied anodal stimulation directed toward left intraparietal sulcus/superior parietal cortex (IPS/SPL; a substrate of selective attention) and cathodal stimulation directed toward right inferior parietal cortex (IPL; a substrate of orienting). Such stimulation during study of verbal materials led to superior subsequent recognition memory relative to the opposite polarity of stimulation. To our knowledge, this is the first application of direct current stimulation to parietal regions implicated in different forms of attention in an oppositional manner in order to modulate learning in a verbal recognition memory task. Additionally, these results may have practical implications for the development of interventions to benefit persons with various types of attentional deficits.
Copyright © 2012 Elsevier B.V. All rights reserved.

PMID: 22265704 [PubMed - in process] "

So has this subject died and been forgotten already?

not very safe resistance of head is change very rapidly they can drp vry rapidly by polarization of neurones and sweating and current can by much higher tan you expect

poisoning - dount care about batteries importat is electrode material dont use TENS
electrodes iectrochemical product is may by dangerous and they have high resitence .
Very important is current density (size od electrodes) in study is about 55uA/cm2

Possibly some useful technical articles:

US-PAT-NO: 7483747

DOCUMENT-IDENTIFIER: US 7483747 B2

TITLE: Systems and methods for enhancing or affecting neural
stimulation efficiency and/or efficacy


---------- KWIC ---------

Description Paragraph - DETX (66):
In some embodiments, a stimulation signal generator may generate or output
a direct current (DC) signal. Such a signal may be applied transcranially at
one or more times, either alone or in association with one or more other types
of neural stimulation (e.g., VNS, cortical stimulation, or DBS). An example of
a transcranial Direct Current Stimulation (tDCS) neural stimulation system is
described by W. Paulus in "Transcranial Direct Current Stimualtion," chapter 26
of Transcranial Magnetic Stimulation and Transcranial Direct Current
Stimulation--supplements to Clinical Neurophysiology, vol. 56, Edited by W.
Paulus et al., Elsevier Science.

Other Reference Publication - OREF (89):
Fregni, Felipe et al., "Anodal Transcranial Direct Current Stimulation of
Prefrontal Cortex Enhances Working Memory," Experimental Brain Research vol.
166, No. 1, pp. 23-30 (Sep. 2005). cited by other

Other Reference Publication - OREF (103):
Lang, Nicolas et al., "Preconditioning with Transcranial Direct Current
Stimulation Sensitizes the Motor Cortex to Rapid-Rate Transcranial Magnetic
Stimulation and Controls the Direction of After-Effects," Biol Psychiatry
2004:56:634-639, 2004 Society of Biological Psychiatry. cited by other

Other Reference Publication - OREF (113):
Nitsche, M.A. and Paulus, W., "Excitability changes induced in the human
motor cortex by weak transcranial direct current stimulation," The Journal of
Physiology, vol. 527.3, pp. 663-639 (2000). cited by other

Other Reference Publication - OREF (115):
Nitsche, Michael A., et al. "Facilitation of Implicit Motor Learning by Weak
Transcranial Direct Current Stimulation of the Primary Motor Cortex in the
Human," Journal of Cognitive Neuroscience 15:4, pp. 619-626, 2003 Massachusetts
Institute of Technology. cited by other

Other Reference Publication - OREF (120):
Paulus, W, "Supplements to Clinical Neurophysiology," Transcranial Magnetic
Stimulation and Transcranial Direct Current Stimulation (Supplements to
Clinical Neurophysiology; vol 56), pp. 249-254, 2003 Elsevier Science, B.V.
cited by other

It would be interesting to experiment with modulating or "chopping" the DC stimulation source with a low frequencies that corresponds to alpha, beta, or delta cranial rhythms. Curiously, there seems to be much anecdotal evidence that the effect seems to evince sustained a alpha state.

Current & voltage limitation circuits are generically available and ubiquitous on the web.

hi, it seems some people will be selling a tDCS Kit.

flowstateengaged.com/

more info:
extremetech.com/extreme/121861-goflow-a-diy-tdcs-brain-boosting-kit

Also there is something called HD-tDCS which is like tDCS but has smaller electrodes for very focused brain zone action.

This topic is indeed very interesting cause it's safe (until proven the contrary) and the technology is cheap.
A brain booster sounds like the college student dream made a reality

Be sure to read all papers you can about this subject, it won't hurt taking a look at Neuroscience-For-Dummies or something (if you are not literate about biologics and stuff) before so you won't have the felling you are reading chinese. Just don't rush it, we are taking about our brains here...

And keep posting your experiences with this tech!

Does anyone have schematics or detailed information for this. Trying to make sure I have it right

I conducted a self test using current between 1uA and 2.5mA with the electrodes in various positions. Here are the results:

• A slight change in perception was first noticed around 40uA.
• Very slight tingling at around 50uA
• At around 100-200uA, the effect seemed to be slightly stronger.
• Tingling at the electrode sites was stronger but still mild and tolerable.
• Further increase in current beyond this point seemed to have little or no benefit.
• At around 1mA, the tingling changed to a slight burning.
• At around 1.5mA, the burning became intolerable for periods of more than a few minutes.
• Further increase in the current only made the burning worse.

Hypothesis: Different individuals may require different current levels to bring about the onset of the effects. Some may notice effects at lower currents. The effect will reach a maximum beyond which further increase in current is no longer beneficial, undesirable, and possibly even harmful.

I hope you find this information helpful.

interesting. Do any you ever dwell ?

You all are wild . Props

Hi,

You are being invited to participate in a research study conducted by the University of Pennsylvania. Your participation is voluntary which means you can choose whether or not you want to participate.

The Laboratory of Cognition and Neural Stimulation at the University of Pennsylvania is involved in research using transcranial direct current stimulation (tDCS). In recent years this technology has increased in popularity, and evidence suggests that some individuals may be constructing their own stimulators for personal use. We are interested in examining the reasons behind this. Please answer the questions below, and email them to braintdcs@gmail.com to give us insight into why people make their own tDCS machines.

Questions

1. Where did you first learn about tDCS?
2. Have you built your own tDCS machine?
3. Where did you get the information to build the machine?
4. Why did you want to try brain stimulation?
5. How long have you been using tDCS?
6. What were your experiences with this technology?
7. Did you ever experience any side-effects?

The research team may use information about you collected from your responses. By completing the questionnaire, you are giving your consent to participate in this study. Once you email us, your responses are not considered confidential since emails do not protect confidentiality.

Thanks,

Research Specialist
Laboratory of Cognition and Neural Stimulation
University of Pennsylvania

[FONT=Geneva][SIZE=1][COLOR=purple]
Using electrical contacts on skin, requires rather meticulous attention to the details of good solid contact.

That usually requires some sort of contact goop or pads wetted with saline solution, upon which the electrodes are placed: these pads or goop assist really good contact.
THAT can generally vastly decrease skin damage from direct contact with metal/electricity to the skin.
It can also change the quality of what one feels from the electricity applied--that tingling should be quite decreased [not impaired nor impeded], by use of good contact pads/goop.

Qs:
===Can tDCS be done using magnets?
===How does one know where to place electrodes? [U]

I definitely want to use something to assist the brain function!

People have used transcranial sound waves to stop migraines; used various configurations of electrostim blinking lights and sounds to quiet the mind and program it to operate better.

The simplest gizmo I ever saw, had what looked like a headset with very small tips, which were placed in an area behind each ear, and a transistor-size thing that ran on a 9v battery was turned on or off by hand.
Fancier gizmos had timers, or could be programmed to stim specific brain wave patterns.

These things have been around for a very long time.
===I wonder, how different this tDCS, differs or is similar, to some of the older gadgets that play with brain waves/function??