So Many tDCS Devices – How to Choose?
Many individuals may be unaware of the fact that the consumer tDCS device industry is relatively new, with the first “commercial” tDCS device hitting the market in 2013. Over the past few years, interest in tDCS has exploded, and subsequently the market has been flooded with new companies producing tDCS devices. Many of the early companies are still around today, but there are also numerous tDCS devices that show up on the market, only to disappear a few months later.
With so many available options, how do you choose the right one? How can you make sure you’re getting a good quality tDCS device? What should you look for and what should you stay away from?
We hope to answer some of these questions for you. The following is not a complete guide by any means. In fact, it’s not really a guide at all! Below is a list of what we strongly believe should be included in every tDCS devices. Sadly, there are A LOT, and we mean a lot, of horribly produced, garage shop, crappy tDCS devices, that not only poorly assembled, but there are a few that we believe are downright dangerous.
The reason we’re calling this page “How to Choose A tDCS Device” is because we suggest you read, copy, print, or download the information below, and refer to it as you do research into purchasing a device. Read all company product descriptions, and if they don’t provide data to compare to the minimum standards located below, ASK THEM! We encourage you to send tDCS suppliers messages/emails/twitter messages etc. and ask them if their devices conform to these minimum standards of safety and operation.
Minimum Standards for Consumer tDCS Devices
The following is by no means an official set of tDCS device standards, however we strongly believe all tDCS companies should ensure their products meet or exceed these guidelines.
We welcome input and feedback from all sources, including tDCS companies, as we continue to build and refine this list of tDCS device standards.
- No Self Adhesive Electrodes – the device should not be sold/packaged with, or marketed to be used with, “adhesive” or “stick on” electrodes. Adhesive electrodes have been widely documented as a safety concern as they can cause burns or lesions at the site of the electrodes. (read more)
- Adjustable Current Output – The ability to adjust the device to a desired level of stimulation (ex: 1mA, 2mA), as opposed to only one current setting (ex: 2mA).
- Maximum Current Output of 2.2mA – The device should not be manufactured to output more than 2 milliamps of electrical current.1 However, due to the precision qualities of electronic components, an acceptable error tolerance of 0.2mA is included.
- Low Battery Indicator and/or Voltage Regulation
- Low Battery Indicator – A Low battery indicator should be included to alert the user when the battery has discharged to a predefined level at which it is no longer able to overcome an acceptable level of resistance (the distance between the electrodes on the body) while producing a constant level of current.
- Voltage Regulation – The implementation of boost voltage circuitry sets the variable voltage supplied by the battery to a constant voltage level used to power the tDCS device. With a constant power (voltage) supply, the device’s ability to overcome external resistance will not reduce as the battery(batteries) deplete over time. If Boost Conversion circuitry is implemented, the manufacturer should publicly state the maximum resistance the device can overcome, before it is unable to accurately produce constant voltage.
- Ability to produce 2mA with 4k External Resistance3
- At the very minimum, the device should be able to produce an accurate current level of 2mA with a montage resistance of 4k (4,000), ensuring the device can operate as intended at the most common tDCS electrode placement montages.
Work on this list is unfortunately taking longer than we had originally hoped. So in the meantime, we encourage individuals to contact us if they have any questions, or are unsure about a specific tDCS device.
Thank you for your patience!
1 2mA is recommended as the maximum limit due to the lack of substantial research into the utilization of current levels above 2mA.
2 If proper low battery detection is not included in a tDCS device, the user is not alerted when the battery reaches a level at which is it no longer effective in powering the device and overcoming external montage resistance. If the battery is not replaced appropriately, the user will be using a non functional device, potentially without realizing so. “many applications do not allow enough current to flow through a load when voltage decreases. This voltage decrease occurs as batteries become depleted, and is a characteristic of the ubiquitous alkaline battery.” -Wikipedia
3Thisis based on our preliminary testing