During the World Cup next week, there may be 1 minute during the opening ceremony when the boisterous stadium crowd in São Paulo falls silent: when a paraplegic young person wearing a brain-controlled, robotic exoskeleton attempts to rise from a wheelchair, walk several steps, and kick a soccer ball. The neuroscientist behind the planned event, Miguel Nicolelis, is familiar with the spotlight. His lab at Duke University in Durham, North Carolina, pioneered brain-computer interfaces, using surgically implanted electrodes to read neural signals that can control robotic arms.
Symbolically, the project is a homecoming for Nicolelis. He has portrayed it as a testament to the scientific progress and potential of his native Brazil, where he founded and directs the International Institute of Neuroscience of Natal. The press has showered him with attention, and the Brazilian government chipped in nearly $15 million in support.
But scientifically, the project is a departure. Nicolelis first intended the exoskeleton to read signals from implanted electrodes, but decided instead to use a noninvasive, EEG sensor cap. That drew skepticism from Nicolelis’s critics—and he has a few—that the system wouldn’t really be a scientific advance. Others have developed crude EEG-based exoskeletons, they note, and it will be impossible to tell from the demo how this system compares. A bigger concern is that the event could generate false hope for paralyzed patients and give the public a skewed impression of the field’s progress.
As his team prepares for the 12 June kick, Nicolelis gives Science a hint of the technology under the hood, and defends his decision to arrange such a conspicuous debut for a tool still in the early stages of development. This interview has been edited for brevity and clarity.
Q: Getting down to the last few weeks before the kick, how is the project progressing?
A: The scientific, the clinical, and the technological milestones have been concluded, so we’re pretty happy. Our eight patients have all experienced walking in the exo[skeleton]. They all had sensations that made them report that they felt like they were walking by themselves.
Q: What’s your primary goal with this demonstration?
A: My primary goal is to disseminate the passion for science around the world. I want people to know that in a country like Brazil that is well known for football, you can also do high-level science, and that high-level science can be produced by a global collaboration, in a nonprofit consortium.
Q: Are you hoping to demonstrate anything to the scientific community?
A: Not in the stadium. We are going to demonstrate a very beautiful thing, but the demonstration for the scientific community will come in the papers that will come afterward. … But we are not preparing this for peer review. This is a show for the world.
Q: How does a person move the exoskeleton, and what can they control?
A: The person has to imagine movements, and these movements are translated into commands that enact the movements in the exo. It’s a concept that we published way back in 2002 called shared control. Part of the higher order decision is done by the brain, and the low-level movement is enacted by the robot. [High-order decisions include] “start walking,” “stop walking,” “accelerate,” “slow down,” “turn left,” “turn right,” “kick the ball.”
Q: How is this system different from other exoskeletons out there?
A: There are several differences. I don’t know any other exoskeleton that is taking commands from the patient’s brain to be activated, move and stop, kick a ball, turn.
Number two is this thing that we call artificial skin. … When the foot touches the ground, there is a wave of signals that are generated, and they are delivered to the arms of the subject through a shirt that contains small mechanical vibration devices. The patients’ brains, after a few sessions of training, associate these vibrations in the arms with either movements of the leg or touching the ground. So we documented plasticity in the brain of the patient.
That feedback creates a higher order control loop that allows them to perform much better than if they didn’t have the feedback. Besides the improvements in motor performance, they have a much more vivid sensation that instead of being carried by a machine, they are literally doing it themselves.
Q: What if the brain signals the person gives on the field, under pressure, are different from the signals in previous tests?
A: We created a virtual reality room in our lab here in São Paulo where a soccer stadium is simulated while they’re doing the task. So we put the noise of football fans celebrating, we put flashes of lights. … If you can do this EEG task while listening to Turkish football fans, like they did, which are the loudest fans in the world, this crowd in Brazil will look like an elementary school class in comparison. Even if they’re screaming with the full strength of their Brazilian lungs, it doesn’t get close to the Turkish guys, I can tell you. We measured.
Q: You originally intended to use implanted electrodes. Why the shift to EEG?
A: When I saw the results of other groups that published invasive technologies in humans, they were really mediocre and not worth the risks of implants. So I decided that it was good, in the case of locomotion, to start with the known phase of technology. We saw that we had a new algorithm for EEG that could do more than I thought we could do before.
Q: You have been critical of using EEG in neuroprosthetics.
A: Yes, I was—and I am—for upper limb control, if you want to reproduce every detail of the kinematics. That is a bogus debate, because I’m doing locomotion, which is a completely different movement.
For the upper limbs, everybody knows that if you’re inside the brain, you get much better results in terms of predicting the entire trajectory. I published tons of papers on this. I pioneered the field, so I know what this is about. Unfortunately, in the U.S. there is such a belligerent, competitive environment. Some neuroscientists cannot take the fact that we are doing something different.
Q: Some have expressed concern that a very high-profile demonstration might give the public an unrealistic expectations.
A: Francis Collins, the director of NIH [the National Institutes of Health], was visiting our lab 2 weeks ago. He was in Brazil and he made a point to come over here just to see that. And he loved it. He said it was a really great idea to profile science in a big sports event, to give something different to the public, for the entire world to see how well science can do and what great things we can expect in the future. So you can ask him directly. He was here, he gave a press conference to the entire Brazilian press lauding the effort and emphasizing that after 20-some years that NIH funded me in the United States, he was very proud and happy to see that a clinical application had come out of this.
We need to make kids love science, and we need to give back to society a feeling that we are doing something with the taxpayer’s’ money. So I think the complaints you get are from people that could not make it to this stage, because they didn’t have quite a good enough idea to make it. There’s a name for it, in English, too. You can find it in the dictionary. We have it in Portuguese here. It’s called sour grapes.
I wouldn’t have been able, perhaps, to do this in the United States today, because its hypercompetitive climate is basically killing basic science and the possibility of doing daring demonstrations like this. I’m trying to showcase the importance of science for society and what it can do for mankind.
Q: Are you concerned that people watching won’t understand how much control the person has over the movement of the exoskeleton?
A: No, because I have been very vocal and very open here in Brazil and all over, showing what is real, what is a possibility right now. This is just to raise awareness for the fact that we have 20 to 25 million people paralyzed around the world, and that science, if properly funded and supported, can do something about it. If we start now—this is just a symbolic first kick—we may be able to do something in the next few years.
Q: When the last game of the World Cup is played, what’s next for your team?
A: After we sleep for 2 weeks once we get this done, we’re going to go back to work. … We have mountains of data that nobody has ever seen. So we’ll be writing a lot of papers and then we’ll be working with the patients to perfect other details of the exoskeleton and to get more clinical data from them.
Q: Brazil will host the Olympics in 2016. Do you have any plans for a demonstration there?
A: Oh, sure. We have plans. Our good friends would love to know them, but we’ll tell them in due time. … I’ll let the critics have one more month of good sleep.
An abridged version of this interview appears in the 6 June issue of Science.