This interface has for a full decade used brain-derived signals to generate movements of robotic arms, hands and legs in animal experiments. A critical breakthrough occurred last year when two monkeys in our lab learned to exert neural control over the movements of a computer-generated avatar arm that touched objects in a virtual world but also provided an “artificial tactile” feedback signal directly to each monkey's brain. The software allowed us to train the animals to feel what it was like to touch an object with virtual fingers controlled directly by their brain.
The Walk Again consortium—assisted by its international team of neuroscientists, roboticists, computer scientists, neurosurgeons and rehabilitation professionals—has begun to take advantage of these animal research findings to create a completely new way to train and rehabilitate severely paralyzed patients in how to use brain-machine interface technologies to regain full-body mobility. Indeed, the first baby steps for our future ceremonial kicker will happen inside an advanced virtual-reality chamber known as a Cave Automatic Virtual Environment, a room with screens projected on every wall, including the floor and ceiling. After donning 3-D goggles and a headpiece that will noninvasively detect brain waves (through techniques known as electroencephalography—EEG—and magnetoencephalography), our candidate kicker—by necessity a lightweight teenager for this first iteration of the technology—will become immersed in a virtual environment that stretches out in all directions. There the youngster will learn to control the movements of a software body avatar through thought alone. Little by little, the motions induced in the avatar will increase in complexity and will ultimately end with fine-motor movements such as walking on a changing terrain or unscrewing a virtual jelly jar top.
Plugging into Neurons
The mechanical movements of an exoskeleton cannot be manipulated as readily as those of a software avatar, so the technology and the training will be more complicated. It will be necessary to implant electrodes directly in the brain to manipulate the robotic limbs. We will need not only to place the electrodes under the skull in the brain but also to increase the number of neurons to be “read” simultaneously throughout the cortex. Many of the sensors will be implanted in the motor cortex, the region of the frontal lobe most readily associated with the generation of the motor program that is normally downloaded to the spinal cord, from which neurons directly control and coordinate the work of our muscles. (Some neuroscientists believe that this interaction between mind and muscle may be achieved through a noninvasive method of recording brain activity, like EEG, but that goal has yet to be practically achieved.)
Gary Lehew in my group at Duke has devised a new type of sensor: a recording cube that, when implanted, can pick up signals throughout a three-dimensional volume of cortex. Unlike earlier brain sensors, which consist of flat arrays of microelectrodes whose tips record neuronal electrical signals, Lehew's cube extends sensing microwires up, down and sideways throughout the length of a central shaft.
The current version of our recording cubes contains up to 1,000 active recording microwires. Because at least four to six single neurons can be recorded from each microwire, every cube can potentially capture the electrical activity of between 4,000 to 6,000 neurons. Assuming that we could implant several of those cubes in the frontal and parietal cortices—areas responsible for high-level control of movement and decision making—we could obtain a simultaneous sample of tens of thousands of neurons. According to our theoretical software modeling, this design would suffice for controlling the flexibility of movement required to operate an exoskeleton with two legs and to restore autonomous locomotion in our patients.
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11 Comments
Add CommentMr. Nicolelis is someone who prides Brazilians. Unfortunately, most of the technology which he helps to develop isn't Brazilian owned. In the future, we'll have to pay high royalties to use it.
Reply | Report Abuse | Link to thisSeems a small price to pay to regain mobility.
Reply | Report Abuse | Link to thisI sure would like to volunteer. C-7 incomplete SCI since 1/08. David Morgan, 424 North Tenth Street, Albemarle, NC 28001 davidmorgan@ctc.net
Reply | Report Abuse | Link to thisA fantastic new technology with exciting exciting prospects for the disabled true enough.
Reply | Report Abuse | Link to thisSo ... "2014" ? oh no ... "perhaps by the next decade" ? .... or as the headline says ".....soon" ?
All sounds a bit confused if you ask me.
The science is exciting, but this article is over the top. As with the much-ballyhooed DEKKA arm that appears frequently on TV, whatever is demonstrated at the World Cup (and I hope the developers meet their deadline) will not be available to the average amputee or brain-injured individual for at least a decade afterward. It turns out that the engineering is as difficult as the science. It's one thing to produce a prototype; it's another thing entirely to produce a supply of devices that are practical in daily life. I wish the scientists all the best, but I urge caution in making predictions. The many men and women who need this science get their hopes up only to find out that the whiz bang stuff is probably not going to be available to them in any meaningful timeframe.
Reply | Report Abuse | Link to thisThe article admits: "We are on our way, perhaps by the next decade, to technology that links the brain with mechanical, electronic or virtual machines.". Let's give those scientists and engineers credit for what they've achieved and wish them luck. DARPA is funding research in this area to help the amputees from Afganinstan gain mobility.
Reply | Report Abuse | Link to thisI would like to preface this by saying that I'm in full support of restoring the quality of life of the disabled. However, I am wary of some of these visions surrounding brain-machine interfaces. We have enough trouble protecting precious banking information that's stored on our computers today, so what would be keeping a skilled hacker from accessing my thoughts, dreams, and memories in the future? We're heading into an age that will be filled to the brim with ethical debates surrounding technological progress.
Reply | Report Abuse | Link to thisScientific progress is necessary for human survival, but sometimes we need to stop, take a breath, and look around us.
"I hope we never fully understand the human brain because somebody will just abuse it." (to that effect) - Theodore Dalrymple.
Technology is moving so fast that anything can happen. Throughtout history, men have been under pressure by the circumstances.And when such scenarios come along the way, we usually come with gib stuff. The cold war has proven this. We never know what event will happen and give emergence to higher technologies. We can even go above the expectations. I believe it's just a matter of time, though no one knows exactly when.
Reply | Report Abuse | Link to thisTechnology is moving so fast that anything can happen. Throughtout history, men have been under pressure by the circumstances.And when such scenarios come along the way, we usually come with big stuff. The cold war has proven this. We never know what event will happen and give emergence to higher technologies. We can even go above the expectations. I believe it's just a matter of time, though no one knows exactly when.
Reply | Report Abuse | Link to thisDARPA funds lots of exciting research into science and technology to aid wounded soldiers, including the DEKKA arm and the work described in this article. I give them and the researchers they fund all the credit in the world -- my son is one of the soldiers waiting eagerly for their work to be deployed and has participated in DARPA funded trials. My problem with this overly optimistic report stems from watching him and other "wounded warriors" gradually and painfully come to grips with the reality that, despite wildly optimistic reports and claims and misleading Today Show appearances, the new technologies will not be available in any timeframe relevant to their recovery and reintegration into civilian life. I would contrast this over-the-top report with the more responsible caution shown by the scientists who recently unveiled their findings re: "junk" DNA.
Reply | Report Abuse | Link to thisI'm the one. I look like the picture At top! I'm in top physical condition and have been a complete C6 quadriplegic for only a year and a half. I am determined like no one else and will fight till my last breath. I have real passion for the beautiful game; before my accident was on two soccer teams and won state in cross-country. I will make the world proud. Contact-801-864-1124 or 801-450-2803 kendra.jean17@gmail.com
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