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Category Transcranial direct-current stimulation (tDCS), Cranial electrotherapy stimulation (CES)
Developer Transcranial Ltd.
Released Developers: 13th November 2014 (V2 edition)[1]
Consumers: June 2013 [2], May 2015 (V2)[3]
Price 299 USD , 399 USD Lucid Dreaming Kit (November 2016)
Max output 2 mA2 T
0.002 A
Session duration 2400 s40 minute
Scalp location Fp1 (above the left eye on the forehead) Fp2 (above the right eye on the forehead) ( V1 stimulator)[5]
Weight g (unknown)

joystick, button, tablet, personal computer, smartphone [6]

Data available
Risk factor
Medical prescription No is a small transcranial direct-current stimulation (tDCS) device. It was developed by a London based company, Transcranial Ltd.[7] The first version of the device was focussed on video game players,[8] but the current version could be used for brain stimulation in general. In addition, the current version of V2-could also deliver different types of brain stimulation, namely cranial electrotherapy stimulation (CES), transcranial pulsed current stimulation (tPCS), transcranial random noise stimulation (tRNS), and double blind sham stimulation.[7] Transcranial Ltd. also sells the Focus Lucid Dreaming Kit that is supposed to provide its users with lucid dreaming.[9]

The first version of the device consists of a headset that includes four sponge electrodes and a battery,[10] and the device is controlled by buttons and an app. It is also shipped with a small bottle and a charging cable.[8] V2's package contains only a brain stimulator, recharging dock, a recharging cable, and a booklet. It does not include electrodes.[7] Its users can connect the device with electrodes that are sold by the company, or electrodes from a third party.[11] The Lucid Dreaming Kit includes a V2 brain stimulator, a sleeping mask, cables, and hydrogel.[9]

Main Characteristics is a standalone device, but its functions are enlarged when it is linked with PC, tablet, or smartphone. This device does not require a medical prescription. However, certain customers should avoid its use due to their specific health conditions such as a history of seizures.[12]

The first version of the device was presented as a headset for video-game players. The headset was made of hard plastic and contained four copper sponge electrodes. Due to construction of the device, the position of electrodes was settled to some extent.[13] However, also allowed a different placement of electrodes if the user purchased the accessory kit. The kit contained two separate electrodes that could be connect to the headset by cables.[14] There were buttons on the back side of the device that controlled the session.[15] The device was charged by the charging cable or the recharging station, and the power was stored in a 3.7 V lithium polymer type battery.[10] When the device was produced, the iOS and Android apps were not finished.[14] Afterwards, the iOS app was introduced, but the Android app was dependent on the upgrade of the Android system.[12] V1 in the recharging station

In contrast to V1, V2 does not contain a headset or even electrodes. The V2 brain stimulator is shipped just with a dock station for charging the device, cables, and the instruction booklet. For safety's sake, V2 also includes triple current regulation, voltage control, and misuse timers. The user could choose the session through the joystick and app. The app controls the device via Bluetooth. The device could provide various ways of stimulation, namely transcranial direct-current stimulation (tDCS), cranial electrotherapy stimulation (CES), transcranial pulsed current stimulation (tPCS), transcranial random noise stimulation (tRNS), and double-blind sham stimulation. Since the stimulation is regulated by the app, the developers claim that there could be some other types of stimulation added in future.[7] There are apps for Windows, OS X, and Ubuntu systems for V2.[16] provides three types of electrodes for V2 that however, have to be purchased separately. The Gamer headset and the Edge headset each cost 79 USD and contain sponge electrodes, while Moovs sticky electrodes are not available at the moment.[17] The Gamer headset has a similar purpose as the V1 device, namely, it focusses on gamers. However, its electrodes could be removed from the headset and used separately. The Edge headset should help athletes enhance their sports performance.[18] On 9 December 2016, manufacturers announced that the V2 device would be shipped with a free 10-20 headcap pack.[19]

Consumers could also purchase a Lucid Dreaming Kit that consists of a V2 brain stimulator, a sleep mask with electrodes, hydrogel, and cables.[9] The sleep mask could also be purchased separately for 9 USD.[20]

A session with the V2 device could take from 1 minute to 40 minutes, and the current can vary from 0.1 mA to 2 mA. There should be a 48-hour gap between each session. The device contains an overuse time prevention to 24 or 48 hours. The maximal voltage that could be delivered by V2 is 60 V, but a user could lessen it manually up to 15 V.[7] If the sponge electrodes are used, they have to be moistened before the start of the session by water or saline.[21] In cases where the sticky electrodes are used, the skin has to be clean in order to avoid burning of the skin.[22]

The first available tDCS device is GoFlow, which was developed in 2012 by two students at the University of Michigan named Matt Sornson and Nick Woodhams.[23] However, they were, unsuccessful, and therefore supported the project that was later developed by[24] The first available tDCS device was therefore V1. It was shipped in June 2013 when developers obtained FCC approval.[2] The new version of the V2 stimulator was unveiled in November 2014 for developers at first.[1] Customers could buy V2 stimulator starting in May 2015.[3]

Lucid Dreaming Kit


The main aim of the V1 stimulator was to enhance skills that are essential for gamers. The V2 stimulator focusses not only on gamers but also athletes and those who want to practise lucid dreaming.

Company & People was developed by Transcranial Ltd., which is based in London, UK. This company was founded by two engineers. They claim, however, that they cooperate with neuroscientist:[25]

  • Michael Oxley: Co-founder and CEO of
  • Martin Skinner: Co-founder of[25]

Important Dates

  • May 2013: Pre-orders of V1 began[26]
  • June 2013: V1 was approved by the FCC and could be shipped to customers[2]
  • 13th November 2014: The developers edition of the V2 stimulator was available for developers[1]
  • 15th May 2015: The V2 stimulator was available for regular customers[3]


The cognitive enhancement linked with the stimulator is based on neurostimulation, even though there are certain studies that claim it does not have the presumed effect.[27] This is the first device focussed primarily on transcranial direct-current stimulation (tDCS), which is non-invasive stimulation of brain neurons by a direct current. The current is delivered by hydrogel sticky electrodes or saline- or water-soaked electrodes. The current is not high enough to let the neurons fire, but it is supposed to make certain changes in their level of excitability. An anode makes the neurons more likely to fire for a certain amount of time, while a cathode impairs their excitability.[28] The V2 stimulator could also deliver cranial electrotherapy stimulation (CES), transcranial pulsed current stimulation (tPCS), and transcranial random noise stimulation (tRNS).

In contrast to tDCS, CES delivers an alternating current. The currents alternate in a certain amplitude (usually less than 4 mA). The precise mechanism of the stimulation has not been sufficiently investigated yet. It is suggested that the current alters the connectivity of neurons.[29] tPCS is based on the alternating current; hence, it is a specific type of CES. In order to provide tPCS the device has to deliver pulses in a rectangular amplitude.[30] tRNS is also a stimulation by the alternating current. Contrary to previously introduced stimulations, the current changes randomly in tRNS stimulation. It ranges within a chosen spectrum.[31]

The V1 device was developed primarily for the enhancement of cognitive abilities involved in playing video games. Certain reviewers reported in increase of a gaming performance.[12][8] However, research conducted by Laura Steenbergen and her colleagues suggest that V1 impairs working memory.[32] This paper caused great controversy in DIY tDCS community, and the relevance of the research was doubted. The controversy is exposed on DIY tDCS websites.[33]

The V2 with the EDGE headset is intended for the enhancement of sports performance. This enhancement is described in' blog posts.[34][35][36] Primarily, any enhancement of sports performance has to precede or be linked with a training. They claim that tDCS stimulation could enhance implicit motor learning. The session requires electrode placement at F3 (high on the left forehead) for cathode and at FP2 (just above the right eye on the forehead) for anode, regardless of whether the user is right- or left-handed.[37] It should take 15 minutes and the recommended current is 1.5 mA.[34] The design of the session was in accordance with research conducted the University of Hong Kong, even though the researchers used a different tDCS device.[38] Another enhancement consists in training longer. The session requires electrode placement on the left temple at T3 (anode) and the contralateral shoulder (cathode) and takes 20 minutes. The recommended current is 2 mA.[36] The session is based on previously conducted research.[39] Finally, the developers argue that tDCS stimulation could increase the intensity of training. In order to obtain these results, they recommend a 20-minutes stimulation with a current 2 mA. The electrodes should be placed at F3 (anode) and the contralateral shoulder (cathode). There is also a study where this setting was used previously.[40] claims that using their device during sleep could lead to lucid dreaming.[41] There is research that argues CES stimulation of gamma frequencies during sleep could induce a lucid dreaming during rapid eye movement (REM) phase of sleep.[42]

The developers clearly claim that the stimulator is not a medical device and hence it is not suitable for therapeutic treatment.[43] They attempted to avoid FDA concerns. However,' motto "take charge" could be considered as a kind of medical claim.[23]

Ethical & Health Issues

There are various health and ethical issues connected with different types of current stimulation. Some of them clearly apply to devices. There is also one health issue that was observed by users of the V1 stimulator, namely, skin burns.

Moovs:' sticky electrodes

In an open letter published in Annals of Neurology, Rachel Wurzman and her colleagues express various concerns regarding tDCS devices, primarily those used outside of laboratories. First, they claim that stimulation tends to influence more region than those users intend to stimulate, since electrodes extend the region to other areas affected by the stimulation. This could lead to unintended effects. Second, brain stimulation interferes with other activities, and therefore could have unintended effects. Third, the enhancement of one skill could lead to impairment of other skills. Fourth, a small difference in the design of the session could change the whole output of the session. Fifth, the brain of each person is unique, and placement of electrodes could differ. In addition, the excitability of each brain varies among tDCS users.[44]

As was mentioned in the previous paragraph, the correct design of a session and an accurate placement of electrodes is essential to the results of the session. Anna Wexler points out that people involved in the DIY tDCS community tends to be acquainted with the research,[45] and Anita Jwa stresses that the community regulates those who make dangerous mistakes and advises them.[28] However, since the device could be purchased by anyone the lack of information could be harmful.

From an ethical point of view, the use of tDCS devices in sports could be controversial. There is still a possibility that this treatment could be considered doping. However, WADA and the International Olympic Committee have not maintained any concerns regarding tDCS devices as of yet. They still monitor, however, their usage.[46]

Users also reported various injuries caused by the V1 device, especially skin burns, generating of current spikes,[47] and a loss of consciousness after using the device.[48] The debater named 'ohsnapitsnathan' argues that the complaints could be partially caused by the fact that the device is the most used tDCS device on Reddit. However, he also points out that V1's sponge electrodes are smaller than regular tDCS sponge electrodes and that the placement of electrodes that is used in the device has not been tested in laboratories.[49]

Moreover, it was deemed that the design of the V1 stimulator, namely, the placement of electrodes, could lead to an increase of aggression in its users.[50][12]

On their website warns that their device should not be used by anybody under 18, since his or her brain is still developing. They also point out the most common risks: skin burns, dizziness, and headaches.[43] The developers stress that the device should not be used by patients suffering from bipolar depression, epilepsy, seizures, severe heart disease, or brain lesions.[21]

Public & Media Impact and Presentation

The stimulator is usually well-evaluated by customers. For instance, the customer 'Labratoullie' argues:

My partner uses it for gaming and it actually does improve his reaction speeds and overall gaming. I use it for morning wake is better than 6 cups of coffee for me, I would know being an addict, and the jolt it gives me is fabulous! My brain processing speed is faster and multitasking is a breeze. For the entire day I'm focused and alert, can't really explain it but I LOVE THIS THING!![51]

However, there were also unsatisfied consumers. A consumer with the nick-name 'mH' complains:

You customer service is nonexistent, your software doesn't work, your website looks and functions like it was designed by a 3 year old throwing a temper tantrum. Of all of the companies I've ever done business with, you rand dead last on who I'd ever recommend![52]

Kate Murphy from The New York Times reported that the first production of the device was sold very soon:

Available online since May, the device was sold out of its first production run of 3,000 in less than a month. “The response has been overwhelming,” said Michael Oxley, a mechanical engineer who is the company’s founder and president.[26]

In the video produced by the BBC, Dr. Hannah Maslen claims that focussed on video game players in order to avoid FDA investigation.

If you were to make a treatment claim, that the device would alleviate symptoms or treat a recognised disease or illness, the device would automatically fall under the medical devices directive and the legislation associated with that.[53]

As was mentioned in the previous section, there were several complaints concerning health issues caused by V1 stimulators. For instance the user 'packmanta' reports:

Okay, I'm still kind of freaking out about this. The instant I put the electrodes to my forehead I saw a bright white flash that seemed to envelop my vision and then momentarily lost consciousness. When I came to, my heart was pounding and I was dizzy, nauseated, and had prickling sensations in my arms and fingers. I lay down and that seemed to help, but I'm still feeling a bit "out of body".[48]

However, the user later claims that the undesirable effects were caused by the fact that he or she used the device in an inappropriate way.[54]

Several customers reported dissatisfaction with' customer service.[55] However, from the recent posts on Reddit it seems that their customer service has improved.[56]

Public Policy was not approved by the FDA since it is not a medical device.[8]

It received FCC approval in June 2013.[2] FCC regulation relates to the amount of the radiation of the device. V2 obtained a CE certified to Medical Standard 60601:2.[7]

Related Technologies, Projects, or Scientific Research

The development of the tDCS stimulator was based on the research concerning tDCS. However, the manufactures are engineers and not neuroscientists.[25] They have not reported any independent research as so yet.

There is one paper that is focussed on the V1 stimulator:

Besides the paper mentioned above, research has not been conducted on the brain stimulator. However, it is mentioned in several papers as a device that could be purchased and that delivers brain stimulation.[23][28][57] also develops the Go Flow Pro tDCS device.


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