Just four months ago, Noland Arbaugh had a circle of bones removed from his skull and paper-thin sensory tendrils slithered into his brain. A computer the size of a small stack of coins was placed on top and the hole was sealed.
Paralyzed below the neck, Mr Arbaugh is the first patient to take part in the human clinical trial testing Elon Musk's Neuralink device, and his early progress has been greeted with enthusiasm.
Working with engineers, Mr. Arbaugh, 30, trained computer programs to translate the firing of neurons in his brain into the act of moving a cursor up, down and around. His mastery of the cursor soon became so agile that he could challenge his stepfather to Mario Kart and play an empire-building video game late into the night.
But as the weeks passed, about 85 percent of the device's tentacles slipped away from his brain. Neuralink staff had to retool the system to allow it to regain control of the cursor. Although he needed to learn a new method to click something, he can still slide the cursor across the screen.
Neuralink advised him against surgery to replace the wires, he said, adding that the situation has stabilized.
The setback became public earlier this month. And while the decline in business was initially difficult and disappointing, Arbaugh said it was worth it for Neuralink to move forward in a medical-tech field aimed at helping people regain speech, vision or movement.
“I just want to take everyone with me on this journey,” he said. “I want to show everyone how amazing he is. And it was so rewarding. So I'm really excited to move forward.”
From a small town in the Arizona desert, Arbaugh has emerged as an enthusiastic spokesperson for Neuralink, one of at least five companies leveraging decades of academic research to design a device that can help restore functionality in people with disabilities or degenerative diseases.
While Musk's presentations have focused on sci-fi ambitions like high-tech consumer telepathy, Arbaugh's experience shows the potential for progress in a medical field where federal authorities will allow such risky research.
Neuralink announced in the news this week that it has received permission from the Food and Drug Administration to continue testing the implants in additional patients. The company did not provide many details about the unexpected flaw and did not respond to requests for comment.
Mr. Arbaugh was paralyzed after a swimming accident in the lush hills of northeastern Pennsylvania, where he worked after college as a camp counselor. Diving into waist-deep water in a lake with a group of friends, he sank to the bottom.
“I was face down in the water and I thought, well, I can't move. So what do I do? I don't think anything,” Mr. Arbaugh said. “So I took a big drink and passed out.”
Mr. Arbaugh was paralyzed from the fourth vertebra in his neck down.
Adjusting to life as a person with quadriplegia was far from the future she had imagined. As a young man growing up in Yuma, Ariz., Mr. Arbaugh had pursued all that his community had to offer. If he wasn't playing soccer, football or golf, he was participating in an academic Decathlon competition or a chess tournament. Among the first in his family to go to college, he enrolled at Texas A&M University, where he smoked too much marijuana, spent a somewhat aimless semester in Australia and skipped too many classes to graduate his senior year.
In the years following the accident, he tried to adapt to a number of devices intended to help paralyzed people. For the most part it failed to function effectively for long periods, although Siri on his iPad has emerged as his most reliable assistant, allowing him to call and send messages to his friends.
Last year, a friend, Greg Bain, told him about Neuralink and urged him to apply for the company's first study in humans.
Mr. Arbaugh said he had no strong feelings about Musk, but felt he was driving progress and that “the things he touched turned to gold.”
After the implant was inserted in late January, he began working long days with Neuralink staff to connect the neuronal patterns detected in his brain to the actions he intended to take. He found the work boring and repetitive, but rewarding.
Once the training was completed, the engineers gave him cursor control on a computer. “I was like, once you take these restrictions off me, I'm just going to fly,” Mr. Arbaugh recalled.
On his first day of solo flight, Arbaugh broke a 2017 world field record for speed and accuracy of cursor control. “It was very, very good,” Mr. Arbaugh said.
Long days spent training computer models with Neuralink staff at his side have now been reduced to remote work in four-hour blocks, Arbaugh said. The team continues to work on tasks such as spelling words, while imagining creating letters in sign language or writing on a chalkboard.
But the Neuralink device continued to lose connection, the tendrils gradually slipping out of the brain tissue and presumably resting in the fluid surrounding it.
When only about 15 percent of the threads remained in place, Mr. Arbaugh lost control of the cursor altogether. Engineers recalibrated the computer programs to perform most of the tasks it had been able to do before. Since he can no longer make the system perform mouse clicks, he is using a new tool that allows him to click by placing the cursor on the item he wants to select.
The faulty implant highlights the concerns of some experts in the field of brain-computer interface. The small round device implanted in the skull is supposed to hold the thin electrode tendrils in place. But like a finger in a wobbly pie, wires can come loose.
Mr. Arbaugh said his brain moved more than the engineers expected and they revised the surgical plan to implant the wires deeper into the next patient's brain.
Neuralink is reviewing requests from others interested in taking part in the trials. Their expenses, such as travel, are covered by the company, according to Neuralink.
This first Neuralink experiment also highlights how complicated the mechanics of the connection between the brain and a device are.
Lee Miller, a professor of neuroscience and rehabilitation medicine at Northwestern University, described the difficulties of working with the brain. It is bathed in salt water, moves as its head turns and bobs, and has immune defenses designed to block invaders. The researchers observed that the brain formed scar tissue around the sensors and even rejected an entire sensing unit that used a grid of tiny needles.
Cristin Welle, a University of Colorado neurophysiologist who started the neural interfaces program at the Food and Drug Administration, which approves medical devices such as implants, said the first Neuralink case suggests the company still faces development hurdles of a durable device.
If the wires were implanted deeper, they could still loosen and leave fibers rubbing on the surface of the brain, possibly increasing the amount of scarring — and signal loss — in the area, he said.
“It's hard to know if it would work,” Dr. Welle said. “It may be that a fully flexible device is not a long-term solution.”
Mr. Arbaugh said his team expected his brain to form scar tissue around the wires at the base of the brain, which they said would help keep them in place. He said he will have the option to leave the firm after a year, but plans to continue working with the company longer. Neuralink said the initial study will take about six years to complete.
Other major trading firms have taken different approaches.
Brooklyn-based Synchron bypassed the brain's delicate tissue by going through a vessel to implant a tiny metal tube near the brain's motor cortex. However, the device doesn't detect as much subtle neural activity as others that penetrate brain tissue, according to industry researchers. It registers stronger signals, so to speak, such as the intent to select an option from an on-screen menu. The company has ongoing human trials.
Manhattan-based Precision Neuroscience has implanted a flexible strip equipped with sensors on the surface of people's brains and is examining data collected from patients with the strip temporarily placed, said Michael Mager, the company's chief executive.
Researchers have been studying brain-computer devices for decades. The standard was a grid of 96 pins, called the Utah Array, which rests on the top of the brain and detects activity up to 1.5 millimeters below the surface. It tends to be connected via a wire in the skull to a small box mounted on the head during ongoing human trials. However, the hole in the skull that lets the wire pass through is prone to infection, and Blackrock Neurotech in Salt Lake City is working on a fully implantable upgrade.
Paradromics, which also uses a grid device based on the Utah Array, is testing its implantable device in sheep and plans to test it in humans in about a year, according to Matt Angle, the company's chief executive.
All work is strictly regulated by the FDA, which evaluates the risks and benefits of the procedures and is expected to first consider the use of these devices in people with severe disabilities or degenerative diseases. (The agency did not comment specifically on Neuralink, but said it requires routine reporting of expected and unexpected events in such studies.)
Beyond that, researchers are divided over the prospect of widespread use by people without disabilities, who might want an implant to communicate without speaking or to download a language, as Musk has mused. Some researchers predict that availability for general consumers will occur decades from now. Others argue that activities such as surfing in the shower will never be allowed, given the risk of contagion resulting from repeated brain surgery throughout life.
Mr Angle, of Paradromics, said he could imagine a progression from use in people without the ability to speak or walk to those with serious mental health problems who resisted treatment.
From there, he said, consumer use could be a decade away. After all, she said, the idea of Botox went from absurd to mainstream in just as much time.
“If 100 years ago you said, 'Hey, rich people are going to inject botulism into their faces,' that sounds totally absurd,” he said. “Once you understand the risks and people can make informed decisions, then everything becomes reasonable.”
Mr Arbaugh hopes to see the technology used first to restore functionality to those who have lost it.
“And then you can allow people to improve their skills,” he said, adding, “as long as we don't give up our humanity along the way.”