Whether foreign adversaries are about to engage in a brain race is unclear, but interest in such technology is on the rise. Darpa has another brain-computer interface project that looks at using the P300 to help intelligence analysts sort through satellite imagery, and the commercial sector is also moving ahead. Entertainment companies are already marketing EEG caps that allow players to use their thoughts to control an avatar in a video game, though the commercial technology is much less sophisticated than the military system.
The technology is also being used to help “locked-in people,” or the severely disabled, communicate by using their brain signals to pick out letters and type. This application works by flashing letters in front of the person, and then recording letters based on the person’s brain signals. The idea is that if the brain is looking for the letter K, then "when you see the letter K, it generates a P300," says Deniz Erdogmus, an engineering professor at Northeastern University in Boston, who builds these systems. Practical applications are still five to 10 years away, but Erdogmus says that in lab experiments trained test subjects are scoring as high as 98%. “We can actually do it right now, it’s just a mater of fine tuning and making it field worthy,” he says.
Though such work is still primarily lab-based, experts do think the commercial sector will eventually improve; at HRL, Khosla sees a number of applications for this sort of brain-machine interface device, pointing to research that’s already being done in everything from the medical field, which is looking to use EEG to control prosthetics, to the automotive industry, which hopes the brain’s ability to detect danger will make cars safer. “Of course the holy grail is, ‘can you decode higher level information in the brain,’ like what is the human thinking?” Khosla says.
Such work, however, is also drawing attention now from scientists concerned that such technology could, for example, allow even more novel use of armed drones. “The ability to control a machine directly with the human brain could, for example, provide the potential to remotely operate robots or unmanned vehicles in hostile territory,” said a recent report by the UK Royal Society.
Jonathan Moreno, a professor of bioethics at the University of Pennsylvania and the author of Mind Wars, says what people find troubling is that, like with drones, such technology expands the battlefield, allowing soldiers to fight remotely. “It’s the projection of human intelligence into a device,” says Moreno. “That’s what it’s about.”
For now, however, researchers are far away from that ‘holy grail’ of mind reading complex thoughts, or controlling drones with the brain; even interpreting basic EEG data is tricky because the human skull basically obstructs the signal. While there have been advances, the best signals are still generated by having dozens of sensors attached to a user’s head with conductive gel, something that is fine for a laboratory, but impractical on the battlefield (another problem: the entire Sentinel system currently weights 7kg (15lbs), too heavy to be used like regular binoculars, though the goal is to get it down to 2.5kg (5lbs)).
Indeed, HRL is still using gel-based sensors for its goggles, though they are working toward something that can be put on and taken off, like a helmet or cap. “The biggest challenge far and away is the sensor: the device or cap that you wear on your head that is sensing the electrical activity in the brain,” says Todd Hughes, a former Darpa official.
Whether the Sentinel goggles are a harbinger of armed drones controlled by soldiers’ minds, or merely a reminder of the limits of new-fangled technology, depends on how far you look into the future. The Darpa programme demonstrates that such brain-computer interfaces can work, and do have military applications, but the idea of machines that can tap into the inner most thoughts of a human being is another matter. “We’re generations away from that,” says Hughes.