Neuralink revealed last week that a tiny wire in its first patient’s brain had pulled out of its place, a problem Elon Musk has known about for years. Five people familiar with the matter said.
Three people familiar with the matter said the company knew from animal studies it conducted ahead of last year’s U.S. approval that the wires could be retracted, removing sensitive electrodes that read brain signals. It is said that
Neuralink determined the risks were low enough not to merit a redesign, the people added.
Neuralink is testing an implant that allows paralyzed patients to think independently and use digital devices, which it hopes will help people with spinal cord injuries.
The company announced last week that the implant’s tiny wires, which are thinner than a human hair, receded from patients’ brains in the first human trials, resulting in fewer electrodes that could measure brain signals.
The signals are translated into actions, such as moving a mouse cursor on a computer screen.
The company said it was able to restore the implant’s ability to monitor patients’ brain signals by making changes such as making the algorithm more sensitive.
The sources declined to be identified, citing confidentiality agreements signed with the company.
Neuralink and its executives did not respond to calls or emails seeking comment.
The Food and Drug Administration was aware of potential problems with the wires because the company shared animal test results as part of its application to begin human trials, one of the people said.
The FDA declined to comment on whether it was aware of the issue or its potential significance.
The agency told Reuters it would continue to monitor the safety of patients enrolled in Neuralink’s study.
If Neuralink continues testing without a redesign, it could face challenges if more wires are pulled and the algorithm proves poorly tuned, one of the people said. said.
However, thread redesign comes with its own risks.
For example, fixating it in the brain could damage brain tissue if the threads become dislodged or the company needs to remove the device, two of the people said.
Current and former employees say the company has worked hard to design the threads to be easily removable so that the implants can be updated over time as technology improves.
In January, Neuralink implanted the device into the brain of its first patient, Noland Arbaugh, who was paralyzed from the shoulders down after a 2016 diving accident.
In the weeks following the surgery, “numerous threads retracted from the brain,” Neuralink said in a blog update last week.
The post did not mention any negative health effects for Arbaugh or say how many of the device’s 64 threads had pulled or stopped collecting brain data.
So far, the device has allowed Arbaugh to play video games, browse the Internet, and think alone on his laptop as he moves the cursor, according to a company blog post and video. That’s what it means.
Immediately after surgery, Arbaugh broke the world record for the fastest time he could control a cursor using just his thoughts, according to Neuralink.
Outside researchers and sources who have worked for Neuralink and other medical device companies say that medical device companies often troubleshoot various designs during animal testing or encounter problems during animal testing or clinical trials. It is said that it is common for this to occur.
Experts who have studied brain implants say the issue of thread movement can be difficult to resolve, due in part to the mechanics of how the brain moves within the skull.
Robert Gaunt, a neuroengineer at the University of Pittsburgh, said the movement of the wire in the immediate aftermath of surgery was disappointing but not unexpected.
“The immediate weeks and months following an implant like this are probably the most vulnerable period,” he said.
pig heaving
In 2022, the FDA initially Neuralink application rejected It has begun human trials and raised safety concerns about the yarn, Reuters exclusively reported last year.
Neuralink conducted additional animal studies to address these concerns, and the FDA granted the company permission last year to begin human trials.
The company found that some pigs implanted with the device developed a type of inflammation called granulomas in the brain, according to three people familiar with the matter and records seen by Reuters. This raised concerns among Neuralink researchers that the threads could be the culprit.
A granuloma is an inflammatory tissue reaction that forms around a foreign object or infection.
In at least one case, the pig developed severe symptoms.
Company records reviewed by Reuters showed the pigs had a fever and were feeling heavy after the surgery.
Neuralink researchers didn’t realize the extent of the problem until they examined the pig brains post-mortem.
Inside Neuralink, researchers discussed ways to fix the problem and began a months-long investigation, people familiar with the matter said.
Ultimately, the company was unable to determine the cause of the granulomas, but concluded that the device and attached threads were not the culprit, one of the people said.
