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THE RISE OF THE CYBORGS— Melding humans and machines to help the paralyzed walk, the mute speak, and the near-dead return to life. by Sherry Baker published online September 26, 2008
“First we build the tools, then they build us.” —Marshal McLuhan
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.”
In 1996 the FDA gave Kennedy the go-ahead for human trials. His first great triumph came with test subject Johnny Ray, a 53-year-old drywall contractor and Vietnam veteran living in Douglasville, Georgia. One day in the fall of l997, while talking on the phone, Ray became one of more than 700,000 Americans each year who have a stroke.
In a coma for weeks, Ray finally woke up in the Atlanta VA Medical Center, his mind intact but his body unable to move or communicate except by the slightest quiver of a few muscles in his face, including his eyelids. He was what doctors call “locked-in.” Blinking twice for yes and once for no, he agreed to participate in Kennedy’s study.
Kennedy and Emory neurosurgeon Roy Bakay implanted a Neurotrophic Electrode near the part of Ray’s brain that controlled his left hand. The outer end was attached to an amplifier and radio transmitter on his skull under the scalp. In the months that followed, Kennedy encouraged Ray to think about moving a computer mouse with his hand.
As Ray imagined moving the mouse, there was an increase in electrical activity among the neurons that would have controlled that action if his hand could move. These brain impulses were transmitted to a receiver on his pillow, where they were deciphered and translated into digital commands sent to a nearby computer. Over time, the computer began to obey Ray’s neural signals. Within six months Ray was moving a cursor on the screen through intention alone, communicating by clicking on icons for phrases like “I’m cold.” Ray kept working with the researchers, although it clearly exhausted him. After more months of practice, he could spell words and hold brief conversations.
As Ray imagined moving the mouse, there was an increase in electrical activity among the neurons that would have controlled that action if his hand could move. These brain impulses were transmitted to a receiver on his pillow, where they were deciphered and translated into digital commands sent to a nearby computer. Over time, the computer began to obey Ray’s neural signals. Within six months Ray was moving a cursor on the screen through intention alone, communicating by clicking on icons for phrases like “I’m cold.” Despite a host of excruciating health problems, including infections (not related to the implant), Ray kept working with the researchers, although it clearly exhausted him. After more months of practice, he could spell words and hold brief conversations.
When Kennedy asked what he felt when he moved the cursor, Ray spelled “NOTHING.” It was a surprising, significant moment. Ray had learned to control the cursor without thinking about moving his paralyzed arm. Neural activity that had been linked to arm and hand movement had changed. Now his brain was communicating directly with the computer.
quadriplegic subjects will walk again—not in 10 or 20 years, but in just a few.
An international consortium based in Brazil called the Walk Again Project includes other participating nations include the United States, Israel, Switzerland, Germany, Japan, and France, as well as a country in the Arab world and one in Africa not yet announced. Together they are aiming to do what sounds miraculous: help paralyzed quadriplegics walk again, not by fixing their lesions or broken spines but by creating wearable robotic exoskeletons controlled by neural signals.
Today we are all in a sense locked-in, but we won’t be for long. “With these experiments we’ve accomplished something that nobody has noticed yet: We have freed the brain from the body. We have created a profound new paradigm for the brain—and not just the disabled brain—to enact its will without the limitations of the biological machinery that we call a body.
“My children probably will see the day when they can sit physically on a beautiful beach in Brazil but at the same time control a rover on Mars, experience Mars,” Nicolelis reflects. “Their bodies will be here, but their brains will be free.”
