(NOTE: The retail packaging and pricing of the Go Flow has changed as of mid-March 2016. See http://www.foc.us for details. This is part 2 of my series on the Go Flow. See http://www.speakwisdom.com for more.)
So you are interested in buying a foc.us Go Flow tDCS* device? What accessories should you buy – and where can you find information on electrode placements and more? In this post I’ll review your options and make some suggestions based on my experience with tDCS and the Go Flow.
(Image from the http://www.foc.us web site.)
Decisions, Decisions – Electrodes First
Oddly, you first need to decide whether you will use sponge or stick-on electrodes in your Go Flow tDCS sessions. Visit www.tdcsplacements.com to see common tDCS electrode placement scenarios. If the one you select involves placing an electrode over hair, stick-on electrodes will not work and you will need to use sponge electrodes. Why this choice comes first will become clear now…
The Go Flow tDCS module can be purchased alone ($9.99) or in a kit including stick-on electrodes and wire. For $19.99 you can get a kit that includes standard hydro-gel stick-on pads or for $29.99 you can get the kit with “Pro” hydro-gel stick-on pads. See www.foc.us for details and ordering information. If you intend to use 3rd party sponge electrodes (like Amrex), you can buy either the $19.99 or $29.99 kit and modify the included cable.
(This is the $29.99 kit – complete and ready to go. It includes the module, wire, electrodes, and battery. Image from the foc.us web site.)
One subtle difference in the two types of stick-on pads is the use of silver as a conductor in the “Pro” pads. It’s important to note that stick-on pads are a “consumable” and must be periodically replaced (sold on the foc.us site.) You’ll need to keep in mind shipping delays in ordering replacements. Also, as mentioned above, stick-on pads won’t work over hair – only on bare skin. I personally prefer to use sponge-type wetted electrodes. Some consider them a hassle (getting them wet, making sure they are not too wet, cleaning them, etc.) However, they can be used on skin or hair and the sponges tend to last for many tDCS sessions.
3rd Party Electrodes
The foc.us Go Flow kits come with a nice connecting cable with magnetic ends designed to connect to specific stick-on type electrodes. If you choose to go 3rd party for electrodes (sponge or otherwise), you may need a different electrode connector. For example, connecting to Amrex sponge electrodes requires a 4mm banana plug. A simple solution is to cut the ends off of the supplied foc.us wire and put on whatever type of connectors you need. Banana plugs are widely available from Radio Shack, Amazon, Parts Express, etc.
(If you are a bit handy, you can cut the default ends off of the kit supplied Go Flow cable and attach your own ends. Here I’ve soldered banana plugs on one of my cables. Note: I fill the shell of the plug with silicon rubber to act as a strain relief.)
I’d love to see foc.us begin to sell preconfigured cables that include banana connectors and pin-type connectors for TENS electrodes (cheap and widely available.)
Going with Amrex Sponge Electrodes (instead of stick-on)
Amrex electrodes (and knock-offs) are widely available from medical supply companies (many online) and Amazon.com . I suggest purchasing the 3×3 size but other sizes are available (you will need two.) You can cut ordinary kitchen sponges to fit the Amrex shell as you need to do sponge replacement. Amrex 3×3 electrodes sell typically for $15 to $20 each depending on the supplier.
Another Cable/Adapter Option for Amrex Sponge Electrodes
If you choose to use Amrex sponge electrodes (or knock offs), you can follow the suggestion above and modify a foc.us supplied cable or purchase the following:
- An adapter that converts the unusual 2.5 mm 4 conductor jack of the Go Flow to a more common 3.5 mm 2 conductor jack. Source: http://www.foc.us/tdcs-tens-cable-adaptor $6 plus shipping
- A cable with a 3.5 mm 2 conductor plug, lead wire, and banana plugs that connect to the Amrex sponge electrodes. Source: http://www.bluemoonhealth.com/tens_supplies_pages/banana_wires.htm $7 plus shipping. This kind of cable can be ordered from a number of different suppliers.
One last possibility if you are handy with a soldering iron is to make your own cable from scratch. www.partsexpress.com is a good source for the needed 4 conductor 2.5 mm plug, banana plugs, and other needs.
Headband for Sponge Electrodes
You will need a headband to hold sponge-type electrodes in place during a tDCS session. A sweatband sold in discount and sporting goods stores will work nicely.
The foc.us Go Flow is a great tDCS device – providing great capability at a very low price. Making the proper selections for your needs is important. Remember, you need the Go Flow module, connecting wire, and electrodes (and perhaps a headband.) The Go Flow kits are a great bargain!
Feel free to post questions on this blog – or email me at firstname.lastname@example.org . What else would you like to know about tDCS by way of this blog?
If you haven’t already, please see part 1 of my series on the Go Flow at https://speakwisdom.wordpress.com/2016/01/20/the-brain-hacking-revolution-continues-introducing-the-foc-us-go-flow-part-1/
Anyone considering the use of tDCS or any brain stimulation technology should do their homework. It’s important to understand the technology, risks, and if you should be excluded based on seizure disorder or other complications. If you are unsure you should seek the advice of a doctor, preferably one using tDCS or similar technologies in their practice.
*tDCS is transcranial direct current stimulation