tDCS to Anterior Temporal Lobe

Out of the few electrode montages that I have tried, my favorite is the Anode to Right Anterior Temporal Lobe (RATL) and Cathode to LATL; it has the most noticeable effect for me. This was studied in Chi 2011(1).

The late evening is the most common time I give myself tDCS (I commonly use 1.0mA because of comfort). After treatments, I normally do not have trouble sleeping (but I normally have no sleep troubles), and in the last few minutes before sleep, my mind is alert and I am thinking of problems that need solutions.

Sometimes I have a noticeable difference the following day (particularly if I gave myself the ATL treatment): my mind is sharp, I am much more focused, and easily moving forward on the many projects at work and personal. Sometimes it gets a little manic; I may be obsessively concentrating on a task for hours and hours but not always. Sometimes I may have an unusually better ability and motivation to write, but not always.

I have been doing the ATL treatments described about twice a week for the two months or so. During that time I have been doing the schematic and layout of the PCB for the DC Stim (the schematic is the functioning of the circuit, the layout is how the ICs and components fit on the board); both very time consuming tasks. It is not my professional job, so I do the work here and there. When assessing effectiveness, of course, it is impossible to say if the treatments definitively helped,  but the product development is a mentally challenging tasks, and I welcome the advantage.

(1) Chi RP, Snyder AW, Facilitate insight by non-invasive brain stimulation. PLoS ONE 2011;6(2):1-7.

The DC Stim

The DC Stim is a medical device designed to provide three levels of regulated direct current for direct current therapies; particularly, the DC Stim has been designed for safe and easy-to-use tDCS applications. Generally, because of cultural bias (fears of media exagerated electroshock therapy and ubiquitous pharmaceutical inroads), people are comfortable ingesting powerful drugs that may have nasty side effects but are very hesitant about applying a small current to their brain! Hence the functioning of the DC Stim was carefully considered to minimize confusion and maximize success. Some of the main functions and features of the DC Stim:

• Three levels of regulated current (1.0mA, 1.5mA, and 2.0mA) selected with a simple slide switch on the front panel.
• A fourth position of the switch to a "Test" position, that will shine an LED when the resistance between the electrodes is low enough for the device to function properly (<10kohms)
• A ramp up and ramp down to minimize discomfort on turn on and turn off.
• A short circuit protection so the output will turn off if the electrodes are shorted together.
• A battery indicator when the two nine volt batteries need to be replaced.
• Small, easy-to-carry unit
• Retail price (when it finally can be sold) of $250 (including electrodes)

I have built a breadboard device (see below) that I use on myself, and eager friends, and I am currently designing the PCB for the manufactured prototype.

I was hoping to do a small run with crowdfunding money but the project was rejected by Techmoola. I have designed the whole unit with off the shelf parts in mind (no large up front engineering costs) hence I am planning now to build 2 - 5 devices to validate all the features and begin the safety testing. Another aim is to submit for IEC 60601 medical equipment safety certificate as a first step to sell abroad as the FDA process of regulating tDCS devices does not look imminent.

Above are two pictures of the breadboard model, of course the manufactured prototype will be all professional looking with fancy membrane switches and a low profile front panel.

I hope to have it complete, built, and tested in less than two months from today. Fingers crossed.

For those technically interested the design is based around switching in particular valued current regulating diodes (with all the safety features added) and is not microprocessor based. This keeps the cost down, but also I feel it is a more robust design (but I would say that since I definitely lean more as a hardware engineer). Keep looking at this blogpost, I plan on publishing the core regulating design.