Every human computer interface is in fact a brain computer interface; it is just a matter of degree. Our intentions may be sent from our brain to computer through our fingers and a keyboard, throughout a camera which tracks eye movement or from sensors that read signals from surface of scalp or from individual neurons.
However, when we talk about brain-computer interfaces (BCIs) today, we are talking about capturing signals directly from brain and using them to control an electronic device. This can be done in a few ways, such as through electroencephalography (EEG) sensors which record electrical impulses from brain or functional near infrared spectroscopy (fNIR) which uses light to monitor blood flow in brain. However sensors can also be implanted these less invasive technologies will work if sensors are worn on headsets which keep them in contact with scalp.
These technologies are not mind readers just yet but they can be trained to recognize patterns in controlled scenarios. We are very far away from me putting an EEG cap on your head and while you think red car, I am able to know that you are thinking about this red car. What we are able to do now, for example: is train system to recognize a choice of four icons or to know that you are thinking red car versus playing tennis.
Thus, a patient with locked-in syndrome might train a BCI to distinguish between two thoughts like playing tennis versus walking down street and these could become their ‘yes' and ‘no' signals. To an extent, it doesn't matter what two thoughts are. We cannot say which neuron in brain fires when you think about playing tennis but we can train a BCI to distinguish between that electrical pattern and another pattern.
Just as everyone walks in much same way but with differences in gait, pace and so on, so we use same types of brainwaves for same kinds of mental activities though there will still be differences between individuals.
As BCIs have advanced we have built up a "library" of signals, so that we can create devices that have ability to track three, four or five patterns. We already have robust technology tools that enable us to obtain clean signals from brain. It used to be essential to wear 128 or even 256 leads on your head to acquire any useful information. Now we can get meaningful data with 16, eight or even four leads, depending on task and signal of interest. Now magic will be in software and what it can do with those signals.
In time we will be able to utilize these types of devices seamlessly for tasks such as controlling cursor on a computer screen or interacting, hands-free, with mobile phones. One of projects that we are currently working on with U.S. Navy is how to utilize both BCIs as well as physiological sensing to optimize individual and team training.
For example, to make training as effective as possible, you could have a BCI that monitors whether you are paying attention properly. If your attention wanders, computer could alert you or ask you to explain material that was just covered. It would be part of an intelligent tutor that paces learning and content to match your focus and attention.
BCIs could also be used to monitor employees in high-stress environments like air traffic controllers or to identify post-traumatic stress disorder in military personnel or concussion in players of contact sports. Given advances in BCIs it seems crazy that every time you visit doctor your blood pressure, temperature, height and weight are checked but not your brain vital signs. You don't need a sophisticated BCI to track brain health even things like reaction time tests can be a good indicator of your brain's processing speed.
EEGs are now just passive monitoring but it is easy to imagine a future where energy can be directed into brain. Preceding year, scientists at MIT used light to stimulate cells in genetically modified mice to implant a false memory into their brains. We are a long way from being able to do that with human beings but we could see an extension of EEG technology to determine when your brain was in a state where it was most receptive to learning.
One profound application for BCIs will be awareness of other people's emotions and brain states. Scientists at Princeton University have looked at speaker-listener pairs with both EEG and brain imaging and have shown that when two people are communicating, speaking and understanding each other, their brains are literally on same wavelength. Not only have that, listener's brain wave patterns start to precede speaker's brain wave patterns. You start to actually anticipate other person's brain waves.
That type of data will have a profound impact on way people interact. Imagine going into every meeting knowing exactly whose paying attention to you, who's on same wavelength as you, literally. Visualize having that kind of information. It will change every single dynamic that you encounter.