A First Step
Nagle is not the first human to operate an implanted BCI. In the late 1990s, neuroscientist Philip Kennedy, the cofounder and chief executive of an Atlanta-based neuro-prosthetics company, Neural Signals, implanted electrodes in the brains of patients. But Kennedy implanted only two glass electrodes, so far fewer neural signals were picked up than is possible with Nagle’s array. Kennedy’s subjects could only move a cursor up and down on a computer screen. Donoghue hopes to make the technology much more functional. In addition to being a professor of neuroscience at Brown, Donoghue is the cofounder and chief scientific officer of Cyberkinetics Neurotechnology Systems of Foxborough, MA, which owns the technology and is running the trial. Cyberkinetics hopes to sell its Braingate Neural Interface System within five years to patients suffering from quadriplegia and other debilitating conditions, including some types of stroke and amyotrophic lateral sclerosis (Lou Gehrig’s disease), says company president and CEO Timothy Surgenor. Surgenor envisions a version of Braingate that would allow patients, with the power of thought alone, to control wheelchairs outfitted with artificial arms and hands, close the blinds in a sunny room, and perform other similar tasks.
The idea of starting a company came to Donoghue in 2000 during a conversation with postdoc Nicholas Hatsopoulos. Originally, says Hatsopoulos, who is now an assistant professor of neuroanatomy at the University of Chicago, the research was solely to study how neurons control movements in monkeys. Then, one day in a hallway in the lab, Donoghue said, “Why don’t we start a company and take this to humans?” Hatsopoulos readily agreed. Since its founding in May 2001, Cyberkinetics has raised more than $15 million and spent about $10 million, and it will need $40 million to $50 million more to keep operating over the next three to five years, until Braingate is approved and can be sold. The device must still be streamlined and made wireless, Surgenor says, and automated so that Nagle and others can use it on their own.
The scientists collaborating with Donoghue at Brown and Cyberkinetics are among the many around the world working on the next generation of neural prosthetics – that is, prosthetic devices animated by human thought alone. Donoghue says this research may one day allow the disabled to walk, and it will perhaps permit Nagle to use his own hands again, by supplementing a damaged, organic nervous system with a functional cybernetic system. Such claims would have seemed fanciful just a few years ago, but other scientists find them plausible. “It’s a very strong possibility that we can do this,” says University of Pittsburgh neuroscientist Andrew Schwartz.
At the same time, however, Schwartz is skeptical that Donoghue’s current device works as well as advertised. “The movements they’re getting are crude,” he says. “It’s not clear how good the human recordings [of the neural signals] are; they haven’t told us this yet.” Schwartz also wonders if playing games, sending e-mail, and turning on the television will really improve the patient’s quality of life unless the patient is “shut in” – that is, so totally paralyzed that he or she can neither talk nor blink and is thus unable to use computer interfaces that are voice and eye activated. “To be useful, it will have to be much better, to do more things,” he says. Schwartz’s own lab has developed a BCI for monkeys that moves an arm with humanlike range and dexterity in a three-dimensional space.
Neuroscientist Miguel Nicolelis of Duke University, another expert in the field of BCI, dismisses the Nagle trial as a “stunt.” “There are other prosthetic devices and interfaces that can do these things,” he says. “To go with surgical intervention, you need to do something more profound. I think they skipped a couple of steps to make this ready for humans.” The electrodes, for instance, are susceptible to clogging with organic matter, he says. Indeed, to work properly, Nagle’s implant may have to be surgically replaced periodically. Nicolelis worries about setbacks for the field if something goes wrong, like an infection following surgery. Nicolelis plans to implant his own sensors in humans in the near future, but only for the purposes of academic research. He is critical of Cyberkinetics’ commercial motivations: he fears that the company is more concerned about cash and promoting its work than about delivering the greatest benefit to patients.
Other neuroscientists support Donoghue. “I think the time has come to do this in humans,” says Richard Andersen, a leading neuroscientist at the California Institute of Technology who is also about to conduct human research using implanted electrode devices developed by his lab. Neuroscientist Bill Heetderks, who headed the neural-prosthetics programs at the National Institute of Neurological Disorders and Stroke until 2003 and oversaw grants to Donoghue, Nicolelis, and other major researchers, points out that the FDA approved the Cyberkinetics trials as safe and promising. He says that Donoghue’s experiments have answered a crucial question that could not have been addressed in an animal study: would human motor neurons still fire up as they would in a healthy person after prolonged paralysis of the limbs? “This was an important reason to do this experiment in a human,” he says. “Now we know the cells still work.”
Donoghue says that every precaution is being taken to protect patients but agrees that Nagle is not able to execute commands very ably. “It’s not like an able-bodied person controlling a mouse,” he says. He argues that even a limited ability is better than none for a quadriplegic.
To potential critics of Braingate, Nagle says, “Have them come down and take a look.” Glancing at his room and his motionless body, Nagle says, “This is my life. I volunteered to do this.”
Nagle says that Braingate is of limited help to him now because he can use it only when the technician is there, and it must be recalibrated each time. “Hey, I want to walk again, or to be able to use this to operate my wheelchair. But this is a first step.” Asked whether he thinks that Cyberkinetics might have rushed to early trials because of its commercial ambitions, Nagle says he’s not bothered. “I think they needed this to get funding, and thank God they got the funding. If they can [help me] make this wheelchair go and sell [that capability to others], then I’m all for it.”