“First we build the tools, then they build us.” —Marshal McLuhan
Robot arm wit a gripper responds to monkey thoughts.
Courtesy Nicolelis Lab
It is a stiflingly hot summer day in Atlanta. Scientist and physician Philip Kennedy has a packed schedule, so he suggests that I interview him while he drives to the tiny town of Bowdon, Georgia, just east of the Alabama line. It’s a journey he takes every Memorial Day to a small cemetery.
We park behind the redbrick Sandy Flat Baptist Church. The sun is blazing overhead, the glare from the white gravel parking lot almost blinding. But Kennedy knows exactly where he’s going. He quickly walks through the simple graves carpeted by carefully tended grass, then stops and bends down. Visibly moved by private thoughts, the scientist touches a simple headstone and leaves beside it a tribute he wrote for the man buried here, a man he calls a hero.
Johnny Ray, who died on this date six years ago, was Kennedy’s patient, his research subject, and the world’s first human cyborg, fitted with brain implants that allowed him to communicate directly with a computer.
Kennedy is the chief scientist of Neural Signals, a company he founded in 1987 to develop a brain-computer interface, or BCI, though he prefers the term “neural prosthetics.”
By any name, the devices created by Kennedy and a handful of others can decode the conscious intentions conveyed by neural signals. For those who are missing a leg or who have a broken spine, the signals can control computers, wheelchairs, and prosthetic limbs. For those suffering from “locked-in syndrome,” their bodies so immobilized by catastrophic disorders like amyotrophic lateral sclerosis (ALS) or brain stem stroke that they are unable to speak or communicate their needs, the devices can translate neural signals to spell out words on a computer screen. Spoken language through a voice synthesizer is coming soon.
Although his current work is aimed at the severely disabled and locked-in, Kennedy believes neural prosthetics will have applications for the well-bodied, too. In fact, he awaits a new, technologically driven stage of evolution that will qualify cyborgs for a branch on the human family tree.
“By connecting intimately with computers, we will take the human brain to a new level,” he says. “If we can provide the brain with speedy access to unlimited memory, unlimited calculation ability, and instant wireless communication ability, we will produce a human with unsurpassable intelligence. We fully expect to demonstrate this kind of link between brain and machine.”
Getting Out
Originally a physician from County Limerick in Ireland, Kennedy was so intrigued by the workings of the brain he decided to go back to school and train as a neuroscientist. After earning a Ph.D., he made his way to Emory University in Atlanta, where, as a postdoc, he began recording and studying neural signals from rats’ brains.
He found the task daunting. Unreliable and laborious, his research required sticking electrodes through holes in the rats’ skulls, risking scarring and infection that could play havoc with data. If the animals moved, the electrodes often slipped out of place.
In l986 while running a lab at Georgia Tech, Kennedy learned that Canadian scientists were spurring neuron growth in rats’ brains by adding bits of sciatic nerve. An idea took shape: Why not create an implant that would spur the brain to grow into it? If the brain could meld with such a device, the nerve cells would hold it permanently in place and risks would drop.
To build his implant, Kennedy took a tiny glass cone, filled it with a mix of nerve growth factors, and ran two fine, coiled gold wires through. Then he inserted it into a rat’s skull, right over the motor cortex that controls movement. Soon neural cells had grown through the implant, keeping it in place and ensuring a solid electrical connection. The gold wires, meanwhile, conducted neural signals through the skull to the outside, where they could be amplified and analyzed.
Then Kennedy performed a simple study. He implanted rats with electrodes in the part of the brain that receives input from the animals’ long whiskers. When he tapped on certain whiskers, he “heard” neural activity via the electrode, but other whiskers didn’t produce these signals. The observation suggested, he says, that “specific neurons were connected to the movement of specific whiskers.” Next he snipped off the hooked-in whiskers and tapped on the alternate whiskers again. This time, to his surprise, the neurons previously assigned to the now-missing whiskers began to adapt, picking up the signals and even causing the remaining whiskers to move. The brain, apparently, was able to compensate for a loss and adapt to fill a need; in short, it was malleable and plastic.
Instructed by this discovery, Kennedy’s vision of a neural prosthesis took hold. If neural activity corresponding to one body part could adapt and move another body part—in this case, whiskers—then perhaps it would be possible to reroute nerve signals on a larger scale, around an injured spine or into a prosthetic limb. Moreover, if the brain’s intentions for movement or language could be deciphered, there might be a way to create an interface between these nerve patterns and the outside world.
Kennedy patented his device (called the Neurotrophic Electrode) in 1989 and spent years testing it in monkeys. Ultimately his increasingly sophisticated technology could amplify neural signals about 10,000 times, converting them to radio waves and transmitting them to an FM receiver. That receiver, in turn, could broadcast the signals as radio waves to a nearby computer.
In 1996 the FDA gave Kennedy the go-ahead for human trials. His first great triumph came with test subject Johnny Ray.
Photos reveal a man with smiling eyes set in a round, slightly chubby face. He was what Southerners call a “good ol’ boy,” a 53-year-old drywall contractor and Vietnam veteran living in Douglasville, Georgia, who liked to play jazz guitar, have a few beers, and hang out with the guys. But one day in the fall of l997, while talking on the phone, he became one of more than 700,000 Americans each year who have a stroke.
