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Mind Control
It started with a game of Pong. Now the science of brain implants promises a future in which blindness and paralysis can be conquered.
By John Carroll. Illustration by Daniel Bejar.
When a knife wound permanently damaged his spinal cord and left him paralyzed from the neck down in 2001, Matthew Nagel found his world reduced to a keyhole view, to what he could hear and see from his wheelchair.
But after two seemingly hopeless years, scientists wired his thoughts to a computer, and he began to do things quadriplegics were once only able to dream about.
A sensing device in Nagel’s brain gave him the power to do simple tasks like playing computer games and sending e-mails. By thinking about where he wanted to place and move the cursor on a computer monitor, Nagel could do so. In a separate exercise, his thoughts were wired to an artificial hand that opens and closes on his order, flexing in ways his own hands no longer can.
“It was easy,” says Nagel in a weak but confident voice, adding that he had the basics down pat after just a few days of trial and error.
“This is really the first time that human thoughts have been linked to a computer,” says Ali Rezai, MD, director of the Center for Neurological Restoration at the Cleveland Clinic, who has been following the development of the BrainGate Neural Interface System being used in Nagel’s trial. And the education that scientists have gained by working with Nagel is giving hope to people with a host of medical problems. It’s possible that the same technology can give them a future to look forward to as well.
The system, with its big computer cord that’s attached to a computer post implanted in the skull, is still somewhat crude and requires more testing before it can be rolled out, but Nagel is a living example of what BrainGate technology can do for quadriplegics. Drop the wires, enhance the software, and add some new tech accessories, and the simple brain games that trial volunteers are playing today will be replaced by a system that offers new ways to have fun, new worlds of communication, and new opportunities to work and to be creative again.
But that’s just the launch phase for this science program.
Connect these devices to ongoing research efforts that use deep-brain stimulation techniques to manage epilepsy and other neurological disorders, and they can start to predict and manage the electrical storms that afflict the brain. Go even further, out to a point where scientists really understand the way the brain communicates, and sensors can be designed to begin feeding back information in ways that can offer a radically new method of sensory input, one which eventually could provide sight for the blind.
TO UNDERSTAND WHAT scientists are doing and where they’re headed, you have to start in the motor-cortex zone of the brain.
This complex group of brain cells is the central command post for turning thought into action, and it works through a form of mental Morse code. Every time you move your arm or leg, neurons inside the motor cortex emit bursts of electronic signals that direct the action. By placing a miniaturized sensor that sends out 100 hair-thin electrodes into this crossroad of brain cells, scientists can tap into that communication stream. A small computer attached to a wheelchair wirelessly transmits the data to a computer that can mathematically translate the electronic pulses into the cursor movements on the screen.
“It’s the rate of firing of individual cells that seems to carry this information,” says Tim Surgenor, president and CEO of Cyberkinetics Neurotechnology Systems, which developed BrainGate and has been testing the neurotechnology in its first human trials.
Whatever the source of their affliction, the four people who’ve participated in clinical tests so far, including Nagel, had lost the ability to move their arms and legs. But their brains have retained the fully functioning signaling system that is needed to communicate with the computer, even though that system’s connection with their muscles has been severed.
The first tests revolve around the simplest of tasks: playing a game of Pong by changing the position of the paddle bar on the screen, communicating by selecting and clicking on words and phrases, and operating a wireless wheelchair or a robotic device. But completing these objectives is a radical step forward for a group of people who had lost all ability to control their surroundings. And it’s been a remarkably easy mental leap for the volunteers to make.
“When using the mouse on your computer, you don’t think about moving your hand — just think about where the cursor is,” says Surgenor. “Soon, they’re just thinking of where the cursor goes.”
And off it goes.
“For someone who can’t speak, can’t breathe, and can’t move to be able to affect their environment through their thoughts is just magic,” says James Allen Heywood, CEO and d’Arbeloff founding director of the ALS Therapy Development Institute. Heywood’s brother, Stephen Heywood, tried the BrainGate technology, signing up early in 2006 after he, formerly an architectural designer, had been completely paralyzed and silenced by amyotrophic lateral sclerosis (ALS), also called Lou Gehrig’s disease.
Stephen was able to go beyond just dreaming about designing homes again — the technology was allowing him to take real steps in that direction. But he suddenly died following a respiratory failure unconnected to BrainGate and thus was unable to further test the new technology.
For Stephen, BrainGate was a way to talk to his wife and children after all communication had gone silent. “It gives you a reason for living,” says Surgenor. “If they can’t communicate, many patients decide not to continue on a respirator.”
SCIENTISTS HAVE KNOWN for more than a century where to find the communications hub in the brain. Having the capability to use that knowledge, though, has been a long time coming.
More than 15 years ago, a group of academics around the country, including John Donoghue, a professor of neuroscience at Brown University, began to wire the brains of primates to computers. Those early primate studies opened the window on what they needed to do to make the technology work with people. But new advances in microelectronics, mathematical code deciphering, and software were needed in order for them to be able to make it work in any practical sense.
“We’re able now to pick up a surprising amount of information,” says Donoghue, whose research was the foundation of Cyberkinetics, the company he cofounded in 2001, where he works one day a week as chief scientific officer. “But it’s a tiny sample of what’s going on. Just reaching for a cup of coffee uses tens or hundreds of millions of neurons. We’re picking up close to 100.”
To make the technology accessible to all quadriplegics, Donoghue is working to replace the wiring with wireless communications. He’s also using more sophisticated sensors, which pick up even more information, so that patients can refine their control of prosthetic devices and robotics. And the professor is seeing the research gain speed as his team gains new knowledge with every new patient and as other researchers leap into the fray.
“It’s coming very quickly,” he says. “A number of groups have miniaturized essential components. The challenge is sealing it to withstand a harsh environment.”
“The ability to link brain signals to a computer or an artificial arm is just the beginning,” says Dr. Rezai, who has been pushing the envelope on deep-brain stimulation, implanting devices in the brain that emit gentle pulses of electrical stimulation to keep the body’s command-and-control unit humming. Ultimately, researchers will be able to detect other electrical storms in the brain, including ones associated with Parkinson’s disease, depression, and anxiety. “The Cyberkinetics system and others are giving us snapshots of the nervous system,” he says.
Right now, the system is used to detect the normal signals associated with movement. Donoghue and others, though, are working on other ways to utilize the technology.
“There’s a lot of blue-sky thinking,” says Surgenor. “There’s interest in providing information to the brain that would augment feeling and hearing.”
One group of researchers, led by Mark Humayan, a retinal surgeon and biomedical engineer at the Doheny Eye Institute at the University of Southern California, has been using the technology to translate camera images into the brain’s electronic language of sensory perception and is beginning to gain some fuzzy images, which the researchers hope to gradually refine into sight.
This kind of technology, says Heywood, can transform lives, possibly even society. On a recent flight back from Los Angeles, Heywood was reading iWoz, the memoir of computer legend Steve Wozniak, and he reached the page where the software whiz described himself as being the first person to type a word on a computer keyboard and have it appear on a screen.
“Stephen and [Matt Nagel] were the first people to think without typing and have their words come up on-screen,” he says. “This is world-changing technology.”
JOHN CARROLL is based in Texas and is a contributing editor to American Way.
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