Electrode Wars! (Well Not Quite)


I’ve written a ton about all the great potential of brain stimulation and particularly tDCS. There are many studies and plenty of anecdote related to improving memory and creativity, reducing chronic pain, treating depression, etc. More about all of that later.

The National Center for Health Statistics just announced that the U.S. suicide rate has climbed to a 30-year high. This coupled with data that we have long had in hand – about 10% of the U.S. population is clinically depressed, that there are about 40,000 suicides in the U.S. every year, and that only about 20% of the people needing depression related treatment actually get it – tells you that our national mental health system is a failure.

tDCS* has emerged as a treatment method that is inexpensive, simple, safe, and has good effect for many of those who use it for depression related symptoms. tDCS use by professionals continues to grow and certainly the do-it-yourself (DIY) community is enthusiastic about it. tDCS requires placing electrodes on the head and passing a very tiny current between them in order to nudge the brain towards proper functioning (or enhancement.)

There are two popular kinds of electrodes, stick-on and sponge. Stick-on electrodes are simple and very useful when hair won’t get in the way. They are used once (or a few times for some) and discarded.  Sponge electrodes are preferred by most using tDCS as it can be used on skin or over hair, can be reused many times, and has a low cost per use.

Amrex has been the big dog in sponge electrodes for the tDCS world for a long time but competitors are emerging and I’d like to cover two of them here. First, Caputron (www.caputron.com) introduced a nice “clone” of the Amrex electrode some time ago and continues to offer it today.  It is available as a 3×3 (typical size used in tDCS) or 2×2 shell (about 2×2 and 1.1 x 1.1 sponge contact dimension). The Caputron electrode does have two distinct advantages – first they are more flexible and conform to curves of the skull more easily, and second they are much less expensive! A 3×3 electrode is only $12! They, like the Amrex electrodes have a banana jack for connection and a stainless steel screen behind the sponge for even current distribution. Also like Amrex electrodes, you can buy replacement sponges from Caputron (about $1 each) – or make your own from kitchen sponges.

(The Caputron shell – orange – with the sponge removed. Note the stainless screen and banana jack. An Amrex shell is shown too – gray.)

Caputron also offers a nice, general purpose strap system that can be used with any brand of sponge electrodes. It’s called the Caputron Universal Strap System and is made of rubber (not latex). There are two independent straps that are marked with a centimeter scale that makes accurate placement of electrodes easy. The system is stretchy and very adjustable for position and head size. I really like this strap system and you will too – if you don’t mind the $75 price.

(The Caputron Universal Strap on my much abused “test head”. The strap is versatile and easy to use.)

foc.us (famous for the foc.us V2 brain stimulation device and the new Go Flow tDCS device) is just releasing a new sponge electrode system  for the V2 and Go Flow that is very interesting! It consists of a rubber-like shell (about 2×2) and sponges that when inserted result in a 1.25 x 1.25 inch sponge contact area. To connect to the foc.us sponge electrodes, you need a special V2/Go Flow cable that attaches magnetically to the electrode shell. That means the problem of having an electrode jerked off of your head should you become tangled somehow goes away. This is a vastly better connection technology than the banana plug and socket used by many manufactures.

(The new foc.us electrode shell and sponge. Note the magnetic ends on the wires for easy attachment to the electrode shells. A new production white Go Flow and 9 volt battery are also shown.)

foc.us is also releasing a companion head strap with strategically placed cutouts that allows easy and repeatable placement of the electrodes on your head. This new strap ships as part of the “Go Flow Pro” which includes the tDCS device, wires, strap, electrode shells (and sponges) and will be available for separate purchase too.

(The new electrode shells, strap, and Go Flow with battery. Note: some electrode setups may require two straps.)

All of the items mentioned in this blog post (including Amrex and foc.us) can be purchased from Caputron (www.caputron.com).  It’s great to have a dealer here in the U.S. that is carrying a huge variety of devices and accessories. I suggest you visit their web site and have a look.

There are many articles about tDCS available on my blog ( www.speakwisdom.com ) and via www.diytdcs.com .

*transcranial direct current stimulation



#4 in the YouTube Series: Treating Depression with tDCS

(Image from the web)


Depression is a significant national problem affecting individuals and their families and friends.  tDCS has been show to have a positive effect in the treatment of depression. The tDCS treatment is very simple and has trivial side effects.

In this YouTube video, the forth in a series, I present information about treating depression with tDCS.  I hope you will find it useful and pass along what you learn.