How brain-computer interfaces read your brainwaves
Premiering as part of Scotiabank Nuit Blanche 2013, My Virtual Dream will be an audiovisual celebration of the intersection of art, science and technology. Inside of a 60-foot dome set up at College Street and University Avenue, special headsets will allow the night’s “dreamer” participants to control a video game and shape the animated dream sequences being projected around them–all using only their brainwaves.
The powerful headsets making this possible are called brain-computer interfaces, or BCIs. BCIs record large-scale, naturally-occurring brain activity. During My Virtual Dream, certain brain activity (for example, states of relaxation or intense concentration) will trigger game actions or animations.
The BCI headsets we’re using have been generously supplied by InteraXon, a Toronto-based firm that creates unique experiences leveraging the ever-increasing power of brain-sensing technology. The MVD headsets are early prototypes of InteraXon’s upcoming Muse headset.
How does a brain computer interface work?
BCIs work by having individuals first try to maintain a particular brain state (for example, “imagine playing tennis” or “try to empty your mind and relax”) while the BCI tries to recognize patterns of brain activity associated with that mental action. When individuals want to use a BCI for a game or to communicate simple commands to a computer, they will try to produce the brain state that the BCI is training to recognize.
It’s important to note that a BCI does not record “thoughts” but rather activity that the brain produces when individuals try to maintain a specific brain state or complete a cognitive task (like, what is the capital of Poland?). When people complete a specific task or maintain a specific brain state, they tend to produce similar patterns of brain activity. The BCI needs to train itself to recognize these brain states, therefore, people should always remember that if the BCI does not work, it is just a limitation of the technology and not their mistake.
How new is this technology?
BCIs are based on brain-imaging technologies, such as electroencephalography (EEG) or magnetic resonance imaging (MRI). Essentially, a BCI is a brain-imaging technology with added software that looks for patterns of activity in real-time. EEG neurofeedback could be considered one of the first common uses of BCIs and has been in use by researchers and clinics for several decades. However, only in the past decade have technologies advanced to allow individuals to own and operate their own BCI at home. These commercial BCIs, similar to the devices used in My Virtual Dream, allow people to play simple games by controlling their brain activity.
What role are the headsets playing in My Virtual Dream (MVD)?
The BCI headsets we’re using for MVD are the sole means of participants interacting with the event’s game and art installation. Participants can compete with each other to see how well they can play a video game that requires either mental focus or relaxation. When they focus or relax in sync with one another, they’ll see a cool animation play out onscreen. During the dream, these same measures of focus and relaxation are used more abstractly to alter animations during the dream sequence. For instance, a scene may have a sky that appears to waver and shimmer, and this could be driven by the collective focus of one of the “pods” or groups of five volunteers. At the same time, another group of five may be altering the movement of a character in the background of the image with their level of relaxation.
Can you explain a bit about how the headset works? The headsets clip onto your ear and press against your forehead — why these points of contact?
Our BCIs use EEG (electroencephalography) and require unimpeded contact with skin. Essentially, large-scale activity from cortical tissue in the brain produces activity that is conducted outward through the skull and can be detected at the surface of the skin. Anything in the way, like hair, clothing, or make-up would interfere with recording this subtle activity. The sensors make contact at the forehead because this area is close to the brain and not covered by hair. The sensors at the ears are actually used as reference points because they pick up environmental noise that can be removed from the forehead sensor to help us get a more accurate measure of brain activity.
What are BCI headsets used for outside of My Virtual Dream?
Commercial BCIs can be used to play entertainment-oriented applications and games, supplement other mental training programs (for example, mindfulness meditation training), or can be used as a tool for implementing simple communication with a computer.
Clinical BCIs can be used to help individuals with diseases or disorders that interfere with verbal or non-verbal communication. Perhaps the most popular use of clinical or research grade BCIs has been by Dr Adrian Own at University of Western Ontario to help individuals with locked-in syndrome (essentially, complete paralysis of the entire body) to have simple communication with others. These patients appear completely non-responsive, but BCIs help them answer simple questions like, “Is your name Michael? Are you in pain right now?”
BCIs have also been in the spotlight lately thanks to work coming out of the lab of Dr. Miguel Nicolelis, for his plan to have a paralyzed child kick off the first game of the 2014 Football World Cup.