What Is It Like to Regain a Sense of Touch, Only to Lose It Again?
A mind-controlled robotic arm might one day feel real, but for its first two paralyzed users, the sensation is only fleeting.
When Nathan Copeland came to, he knew he was paralyzed. Still in the driver’s seat, he looked at the fireman kneeling beside him and said, “I fucked my life up.” The fireman said, “Let’s get through right now.” A helicopter landed in the nearby baseball field. Copeland started crying. He hadn’t even wanted a driver’s license, but he needed one for the half-hour drive to Fayette, where he’d just started studying nanotechnology at a branch of Pennsylvania State University. He’d been rushing that night in the rain. He took a corner too fast. His tires hit mud, the car hit the guardrail.
Copeland was paralyzed from the chest down. He could move his arms, but his triceps didn’t work. He couldn’t move his fingers, so his therapists let them curl. This allowed him to pick stuff up—like a hooked cup—as long as it wasn’t too heavy. Over the years, he watched as his former friends hit all the milestones—graduate college, get jobs, marry, have kids. He participated in life as he could, often helping the Pittsburgh Japanese Culture Society with web work, since he can type with his pinky knuckles. But he sometimes felt useless.
All this changed in 2014, when at the age of 28 Copeland was selected to participate in a mind-controlled robotic-limb study at the University of Pittsburgh. This brain-computer interface works by hooking up the brain to an external robotic arm in a lab. Other people have controlled robotic arms with their brains, but Copeland was the first to receive signals back from the arm, enabling the sense of touch. In other words, Copeland is now able not just to move the arm, but feel with it.
The neurosurgeon Elizabeth Tyler-Kabara cut open Copeland’s head and placed microelectrodes on his motor and sensory cortices. After Copeland recovered from the surgery, a team of researchers got down to training his brain to interact with the robotic arm by hooking it up with thick cables three times a week, up to four hours at a time. Participating in the study has given Copeland’s life meaning and purpose, and even a little bit of fame. In 2016, he got to shake hands with, and fist bump, President Obama.
But there’s a catch. Copeland can only participate in the study for a maximum of five years. So what happens in two years, when his sense of touch—and purpose—is taken away?
* * *
Before Copeland, the Pitt researchers worked with Jan Scheuermann, now 57, for two-and-a-half years. It was the first time the team implanted the robotic arm’s microelectrodes in a brain. They do so with a device called a microelectrode array, which has a square base and about 100 needles. Each needle sends and records signals from an individual neuron.
The technology comes from research that found a monkey’s neurons fire in the same way when it thinks about moving as when it actually moves. The team realized they could bypass muscles (like those cut off from the brain by spinal cord injuries) and use the brain itself to move a robotic arm.
Scheuermann achieved 10 degrees of movement with the arm, what the researchers called 10 degrees of freedom: up/down, left/right, forward/back, and so forth. She loved every moment of the study. It got her out of her chair, out of her broken body. For part of the research, she flew a simulated plane with her mind: She took off from a beach in Hawaii, flew through the Eiffel Tower, buzzed past the pyramids.
Then her scalp around the two receptors on her head started to pull away. Tyler-Kabara and the physician Michael Boninger decided that it posed too much of a risk of infection and immediately removed them. Scheuermann was distraught. She didn’t get to fly one last time. She didn’t get to say goodbye to the community she’d been a part of at the lab.
Now, she keeps herself busy—writing her book, My Life as a Lab Rat, doing The New York Times crossword puzzle, corresponding with people on the internet, speaking to groups whenever she can. But Scheuermann is in a different situation than Copeland, whom she befriended after he underwent surgery. She’d already lived a full life by the time she was completely paralyzed neck-down in 2001, the result of Spinocerebellar ataxia, a degenerative disease somewhat similar to multiple sclerosis. She’d successfully run a murder-mystery dinner-party company. She had a husband and two children.
Scheuermann has an innate optimism that can’t be squashed. After surgery, she dressed up in mouse ears and whiskers, and told the researchers, “I’m a lab rat now.” She dressed up the receptors on her head, too. They were ghosts for Halloween, had Santa hats for Christmas. She gave the robotic arm a name: Hector. She made him walk a dog, work a marionette, pull a rabbit out of a hat.
By contrast, Copeland was fairly withdrawn before the study, says Tyler-Kabara. “Now he gets to hang out with people doing the things he wanted to do [in school].” Copeland is excited about being involved in something bigger than him, and he’s the first to admit that it will be tough when the study is over. He knows he’ll go through a depression.
Copeland and Scheuermann don’t gain a robotic arm, they only borrow one sometimes in the lab. And the process isn’t without risk. That’s why the study uses only paralyzed subjects; brain surgery that might result in loss of function can’t ethically be conducted on a healthy, mobile person. (Although there was one researcher in such desperate need of a subject that he went to Central America and had surgeons implant microelectrodes in his own brain, but that’s a whole other story.) Technically, all Copeland and Scheuermann really get is surgery and a job for one to five years—the Food and Drug Administration limits the implant time for patient safety. Boninger, the study’s principal investigator, explains that in ethical review paperwork, “We say there really is no benefit [for patients].”
But Boninger insists “that couldn’t be further from the truth.” Both Scheuermann and Copeland see the experience as life-changing, considering themselves explorers. Scheuermann even named the two ports on her head Lewis and Clark.
* * *
At a recent lab session, Copeland sat in his wheelchair in a room that contained thousands of dollars of equipment, but looked just like any room in an office building. A grad student cleaned the receptors sticking out of his head. Copeland says they’re a little weird, but not painful. “Fashion is another thing. I could comb my hair to the side.” The first two hours were devoted to basic pick-up-and-move-things tasks to record data for one of the grad students. The mood was sleepy and monotonous; everyone was on their phones. Copeland drank a Gridlock energy drink.
The second part of the day was more energized. The researchers whispered in the corner and then talked to Copeland, telling him what to do. At the end, a researcher explained to Copeland what they were hoping to do: make the sensation of touch feel like it lasted longer, because it fades quickly even when they continue stimulation.
The researchers like to think of Scheuermann and Copeland as partners, collaborators, even though Scheuermann is no longer a part of the study. They stay in contact with Scheuermann; she got to be there for Obama’s visit, when not all the researchers were invited. Copeland’s time in the study will come to an end, too. But the scientists will continue with new participants and new studies. The non-human primate lab, which does the research on the monkey brains, is currently experimenting with optogenetics, using light rather than electric shock to control neurons. This technique is more precise and doesn’t fatigue or damage the nerves like electrical stimulation.
When they no longer get to experience what it’s like to feel things again, the robot-arm subjects have to go back to normal life—a limited life—and try to make the best of what’s left. Copeland wants to participate in more brain-computer interface studies, but having done this one probably excludes him from everything except privately funded experiments. He thinks about doing motivational speaking like Scheuermann, but he doesn’t have much faith in his public-speaking abilities. He’ll certainly continue his volunteer computer work with the Pittsburgh Japanese Culture Society. He’d love a paying job.
“Someone needed to do it, and I was able to,” Copeland says of the study. “I don’t even need people to remember me as the guy who made this possible. I truly hope for a future where this isn’t even awesome, where it’s just an everyday thing.”