For years, researchers have explored the potential of brain-computer interfaces (MCIs) – systems that connect the human brain to external technology – to restore movement in people with paralyzed limbs, using arrays of electrodes implanted directly into the body. the surface of the brain.
In the future, however, research supported by the US government may allow the use of ICMs without any surgery – and they may first consider their use as a way to give soldiers an edge on the battlefield.
DARPA, the U.S. Army’s research and development unit, which launched its Next Generation (N3) nonsurgical neurotechnology program in 2018, seeks to create non-invasive, or minimally invasive, brain-computer interfaces that could allow troops to communicate with systems from air vehicles or cyber defense systems more quickly than with voice or keyboards. Additionally, soldiers could potentially pilot drones or tanks with their only thought.
Six funded projects
“DARPA is preparing for a future in which a combination of unmanned systems, artificial intelligence and cyber operations could cause conflicts in too short a time frame for humans to effectively manage with current technology alone,” says Al Emondi, responsible for the N3 program last year when funding for six projects was announced. “By creating a more accessible brain-machine interface, which does not require surgery to be used, DARPA could provide tools that allow mission commanders to remain meaningfully involved in dynamic operations that unfold at rapid speed. . ”
The research agency has awarded funding to six groups under the N3 program, each studying a different method for allowing humans and machines to communicate at the speed of thought, but without involving surgery. The different groups are looking at a whole range of approaches. Ultrasound, magnetic fields, light, electric fields, and optical coherence tomography (OCT) are among the technologies being researched.
Ohio-based Battelle R & D is one of six groups to receive DARPA funding for a minimally invasive system that should eventually be able to collect and transmit information to soldiers’ brains. . “Imagine this: a soldier puts on a helmet and uses his only thoughts to control multiple unmanned vehicles or a demining robot,” as the company described it last year .
The objective of the project is “to improve the capacity of our soldiers and our fighters – to learn faster, to do things better”, specifies Patrick Ganzer, principal researcher at Battelle, to ZDNet. The Battelle system is based on nanoparticles and uses their electromagnetic properties to collect and communicate data to the wearer.
Challenges to overcome
According to DARPA, the main challenges in developing non-invasive, or minimally invasive MCIs, are overcoming the signal-to-noise ratio and “the complex physics of scattering and weakening of signals as they pass through the skin,” the skull and the brain tissue ”. Battelle believes that using electromagnetic waves, rather than light or ultrasound, should overcome the problem.
Once L3 participants figure out how to process the physics of ICM, says DARPA, they can proceed to codify and decode neural signals, create a unique sensing and stimulation device, and test safety and efficacy. systems in animals, then move on to experimenting with human volunteers. Although it is not yet clear how the brain might react to the introduction of thousands of nanoparticles, the use of other nanoparticles in medicine may provide some clues. Nanoparticles are already used in hospitals as a contrast medium, a substance that is injected or swallowed by patients to make certain parts of the body more clearly appear on a CT or MRI scan.
DARPA estimates that ICMs should be able to be used for two hours, but it is conceivable that real-world systems will have to be in situ for much longer to cope with long missions, possibly being re-injected or re-magnetized in order to maintain them. in place for longer term use.
Medical applications
Creating a system capable of operating in the harsh environment of the human body is one thing, but creating an ICM capable of handling the complexity of human thought is another. The development of the interface of a minimally invasive system is a real challenge because if you make it too simple, and it is not useful, but if it is too complex, it is difficult to handle by the user.
“There is a trade-off between the complexity of feedback and how quickly you feel it intuitively. Imagine you have a very simple feedback system. Let’s say there are four places, and each of them means something different that you learn over time. If I increase that number to eight or twenty, or something more complex, I start to put a heavy load on the user. There’s an operational hotspot where it’s easy to use, doesn’t have to learn a lot, and you don’t have to think about it – it has that natural side. Like all good technology, it simply works, ”explains Patrick Ganzer.
Much of the groundbreaking research on brain-computer interfaces is focused on medical applications. By bypassing broken connections in the pathways that lead from the brain to muscles and skin, MHIs could help overcome the paralysis and loss of sense of touch that result from strokes and spinal cord injury.
This work typically involves invasive ICMs – systems that require surgery to implant electrode arrays into the brain – but the new wave of non-invasive or minimally invasive systems may offer a non-surgical alternative in the future. The prospect of a non-surgical alternative could also make it possible to use this type of interface in a greater number of cases. According to Patrick Ganzer, besides spinal injuries and strokes, minimally invasive systems could potentially be used for epilepsy and depression.