Elon Musk’s brain technology startup, Neuralink, said Wednesday that an issue cropped up with its first human brain implant weeks after it was inserted into a patient.
The company revealed in a blog post that in the weeks following the patient’s surgery in January, a number of the implant’s connective threads retracted from the brain, causing a reduction in the signals the device could capture.
Neuralink provided few other details about the problem and did not disclose what might have caused the threads to retract.
It did say, however, that it modified an algorithm “to be more sensitive to neural population signals,” meaning it was able to improve how the patient’s brain signals were detected and translated.
Neuralink’s first human patient, Noland Arbaugh, 29, lost all movement and sensation in his arms and legs after a diving accident in 2016.
Neuralink’s N1 device, about the size of a quarter, is designed to be fully implanted on the skull. It is connected to the brain’s motor cortex through 64 ultra-thin threads with tiny electrodes that pick up neural signals from the patient.
It’s not known whether the retracted threads posed any safety concerns for Arbaugh at the time.
In March, the company hosted a livestream during which Arbaugh moved a cursor across a laptop screen and played online chess using only his thoughts. In other videos released by the company, Arbaugh appeared to play the racing video game Mario Kart with the brain chip.
The latest update comes less than a week after a Neuralink co-founder, Dr. Benjamin Rapoport, suggested on an episode of The Wall Street Journal’s “The Future of Everything” podcast last Friday that he left the company because of safety concerns.
Rapoport, a neurosurgeon, co-founded Neuralink with Musk and other scientists in 2016. He later left to start a new company called Precision Neuroscience.
“I’ve pretty much devoted my entire professional life to bringing neural interfaces from the world of science to the world of medicine. But I’ve felt that in order to move to the world of medicine and technology, safety is paramount,” he said on the podcast.
It was not the first time the company has faced controversy. Activist groups and internal staff complaints have alleged that Neuralink mistreated some of the animals used in experiments. A federal investigation did not turn up evidence of any violations beyond an “adverse surgical event” in 2019 that the company reported itself, according to Reuters.
Neuralink won approval last year from the Food and Drug Administration to conduct its first human clinical study. It has been developing a brain implant that would allow people, including patients with severe paralysis, to control computers, phones or other external devices using their thoughts.
