The Rise of the Cyborgs
Melding humans and machines to help the paralyzed walk, the mute speak, and the near-dead return to life
Interesting passage from the article:
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.” 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.
“The brain is very adaptable,” Kennedy says in the Irish accent he has kept after almost three decades in the United States. “The brain’s plasticity is the key thing to this whole field.”
And this passage offers new insight into language -- that it's less an abstract quality of consciousness and more a product of the muscles in the mouth and face moving.
His mind is fine but he cannot move, except for tiny eye gestures (up for yes, down for no) and occasional muscle spasms. I ask him if coming to the lab is fun. He looks down. Is it more like work? He looks up. He is an inner-space pioneer whose work holds the promise of freeing himself and others who are locked-in, at least to a degree, by eventually allowing them to have real-time conversations.
“Developing a neural prosthesis for speech is extremely important to me,” says Kennedy, who, as a neurologist, regularly sees patients with ALS and stroke. There are some 30,000 ALS patients in the United States alone. All will become locked-in eventually, and 5,000 to 6,000 each year are at the point where they must decide whether to spend the rest of their lives on a ventilator, unable to speak, or to refuse it and let themselves die. If they knew they could continue to communicate as their disease progressed, they would undoubtedly more often choose to live, and they could even be productive. “People call my office all the time about a loved one who has had a brain stem stroke, lying in bed, unable to speak,” Kennedy says. “I expect to be able to help these people with this research.”
In the effort to unlock the door, Ramsey is treading where no one has gone before. The brain’s precise speech center varies from person to person, so to find Ramsey’s target area—the place where an implant could discern the appropriate speech signals—Kennedy used a functional magnetic resonance imaging (fMRI) scan. Showing Ramsey pictures, he told the young man to say to himself phrases like “This is an elephant” and “This is a dog.”
As Ramsey “spoke” internally, the MRI pinpointed neurons associated with speech, but the results were surprising. The neural signals were not sparked by words or their meanings, per se, but instead by how the muscles of the lips, tongue, jaw, and larynx would move to produce the sounds—movements that Ramsey could only imagine.
Read the whole article.
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