Until recently a purely lab based technology, brainwave (electroencephalograph or EEG) headsets are trickling into the marketplace in a number of different guises. But what exactly do these devices do, how do they differ from each other and - with potential applications ranging from medicine to gaming and market research - who will use them and for what purpose?
There are at least four areas of applications for brainwave detection devices:
- Medical/clinical applications
- Assistive technology for people with disability i.e. to control, for example, a wheelchair or a mouse
- Hands-free gaming
- Market research - evaluating new ads or packaging by reading consumer brainwaves
Let's start with one of the latest headsets to be unveiled - the Mynd. Announced late March 2011, it is described as "the World's First Wireless Full-Brain EEG Headset". That description sounds impressive but who is it for?
The Mynd headset is primarily for market research. You can't buy one at this stage because it is the product of Neurofocus, a Nielsen backed market research company that uses Mynd to provide ad and pack testing services for advertisers. Neurofocus may decide to sell the headsets later but for the moment, the company is satisfied to claim a competitive advantage for its market research testing services.
The Mynd is wireless, uses dry, "smart" electrodes (thus eliminating the use of gels) and is claimed to provide full-brain coverage using "a dense-array" of EEG sensors, each one capturing brainwave activity at 2,000 times a second.
Number of sensorsOne of the key differentiating factors in brainwave headsets is the number of electrodes or sensors. The typical, medical EEG uses 19 electrodes, that is, 19 channels of information being read from the scalp. In some cases, very high densities of 250 or more are employed. More sensors means greater brainwave information and more "thought resolution" can be achieved. This is important as we will see later as some headsets use a very limited number of electrodes. Headsets that use just one or two electrodes for example, cannot be expected to give the "thought resolution" that 19 sensors can provide.
Dry v Wet technologyMeasurement of EEG brainwaves has traditionally had to use gel, paste or saline at the scalp terminals to ensure conductivity of the electrodes onto the scalp. The Mynd headset relies instead on natural skin-oils and sweat to create a sufficient connection and the company claims similar performance to that obtained by wet-based systems.
With dry technology and a Bluetooth enabled headset, Neurofocus boasts the convenience of its EEG testing for market research environments beyond the lab. That is, it can be used in consumers' homes, at movie theaters, in shopping malls as well as at outdoor venues. It enables consumer EEG data to be streamed via Bluetooth to any portable smart device, such as an iPad or iPhone.
Neuromarketing tests - are they valid?EEG is only one form of what is called "neuromarketing" evaluation testing ... but an important one. This type of testing has been attracting growing interest but it also has its critics who see it as junk science and suspect market research. Indeed, whether such studies produce valid, reliable, market research results is a question that is currently being addressed by a well-respected, independent body, the
Notably, Neurofocus was one of two key suppliers that declined to take part in this independent review process. Notable also is the fact that the other major company that declined to take part also uses dry headset technology. This is the Emband, a product of Emsense (a company partnered by the global market research giant, Millward Brown). Neither the Mynd or the Emband headset is available to buy at this stage, and you can draw your own conclusions as to why these two companies declined to take part. But since the dry technology players were missing, one has to conclude that dry technology is as yet unproven in the market research space.
If you are interested in what the ARF found, you can watch the presentation of its first-phase findings from March 2011 here. There is little detail except for one commercial tested - the Colgate Total toothpaste commercial. Most of the neuromarketing suppliers agreed the ad was good, but the detailed findings between the companies were disturbingly different. "Across eight vendors, there was not a whole lot of consistency," according to Colgate's director of strategic insights. Some companies, for example, said the characters in the ad were "inviting" while others thought the same characters did not resonate with the target audience. The ARF is expected to release a more extensive "white-paper" on this study around September 2011. But for now the review offers a very conservative position that neuromarketing testing has promise but is, at this stage, a supplement and not a replacement for more traditional market research.
Beyond neuromarketingEEG headsets for other uses, especially gaming, represent a somewhat less complex problem than market research testing. The emphasis here is on mapping a thought to an action. So for example, gross motor thoughts like imagining you are "pushing a ball away from you" can be mapped to moving a game character forwards, or a facial expression like raising your eyebrows can be mapped to firing a gun in the game. For this sort of purpose, there are a couple of dry technology headsets emerging that are quite cheap and seem to work OK for rather limited gaming application.
Neurosky's technology is making its way onto the market in products like the Star Wars Force Trainer and its US$100 headset called MindWave is aimed at gaming and simple video applications. It is a mass market version of the company's Bluetooth enabled, $200 MindSet. This headset has only one electrode (reading from the forehead where the signal is easier to detect because there is no hair). This single electrode is mainly designed to detect how attentive versus how "meditatively" relaxed the user is feeling as they interact with games, video and learning applications. As mentioned earlier, one electrode cannot give the "thought resolution" of 19 sensors so gaming applications like this have their limitations.
The Neural Impulse Actuator is another dry headset marketed primarily as a game controller and again uses very limited channels (it is not clear how many channels but it looks like 2 or 3). The sensors seems to be focused heavily on detecting facial movements as much as brainwaves. OCZ Technology sells the Neural Impulse Actuator for around US$100 but clearly, even for gaming, it is early days in the state of development for dry technology headsets.
The alternative to dryIf you want a serious headset with adequate electrode channels to provide for a broader range of applications, what alternatives are there?
The least invasive and most convenient alternative to dry technology is to use terminals with pre-moistened saline pads. After extended use, the sensors require re-hydration with new saline fluid but the technology is nevertheless, low cost and very usable.
An attractive and comparatively low-cost offering here is the EPOC headset by Emotiv that was demonstrated at TED in August 2010. It has 14 sensors plus an inbuilt two-axis gyroscope that also allows tracking of head movements.
If you only want it for approved games or applications designed specifically for the EPOC, the headset costs US$299. If you are a developer and want to use it more fully, the cost is $500 for the Developer headset.
The Developer version comes with a Brain Computer Interface (BCI) that while fairly simple, is nevertheless an order of magnitude cheaper than anything else comparable. On the basis of the 14 channel input, the EPOC BCI is easily able to translate brain activity to enable it to be mapped onto a wide variety of computer commands. For people with disability, I think Emotiv's corporate tagline says it brilliantly: "you think, therefore, you can."
This EPOC headset is currently being piloted for various gaming applications and disability enablement applications around the world. If a person cannot speak or cannot speak clearly, as is the case with many cerebral palsy sufferers, speech recognition technology to control smart devices is just not an option. Various organizations (like Thought-Wired for example) are exploring the potential of low cost headsets like this to enhance the lives of those suffering from a profound disability.
As well as attracting the attention of disabled gamers, by linking the headset and a BCI to smart-home appliances it can enable people to do things like control room lights, curtains, room temperature or alert carers to their needs. Eye tracking technology can do the same thing, but this turns out to be cheaper.
Emotive seems to be winning considerable respect for its Epoc headset as its claims have been cited by no less than the highly respected British Royal Society.
The EPOC headset can also detect a variety of facial expressions including smiling, laughing, and smirking as well as eyelid and eyebrow positions. This enables a user's facial expressions to be communicated in online communication through an avatar or converted into email in the form of emoticons.
What does the future hold?EEG headsets have broken out of the laboratory into the wild and while their numbers are still sparse, they can be expected to develop rapidly.
In the next few years we can expect some exciting applications to emerge, particularly in disability applications. In relation to gaming, they seem to be a solution looking for a problem at the moment, but they undeniably have novelty appeal. So the jury is still out. as it is in the market research arena where it will take some time to sort out the substance from the hype - as applies to neuromarketing more generally.