Last week, the Elon Musk-backed brain-computer interface (BCI) maker reported that several threads retracted from the brain in the weeks following the implant procedure. The retraction led to a net decrease in the number of effective electrodes and a reduction in data bits-per-second (BPS). This metric measures the speed and accuracy of the patient’s ability to use the BCI technology to control a computer mouse cursor.
Neuralink declined to disclose why the threads retracted.
Reuters said today that people familiar with the matter say Neuralink knew of this issue for years. The company reportedly knew from animal testing performed ahead of FDA approval for the first-in-human trial in May 2023. However, Reuters said the company felt the issue was not enough of a risk to require a redesign effort.
One source told Reuters that the FDA was aware of the wiring issue because of the animal testing required to kick off human trials. The report said the “FDA declined to comment on whether it was aware of the issue or its possible significance.”
According to the report, redesigns could bring risks like brain tissue damage if Neuralink decided to anchor the wires to the brain. The current design is supposed to make thread removal seamless to enable updates over time, Reuters said.
Background on the first human implant
In September 2023, Neuralink opened up recruitment for its first-in-human clinical trial after the FDA OK’d it.
Musk said in January that the first patient received their implant, which he plans to call “Telepathy.” Remotely rechargeable, the implant goes along with electrode-laced threads that go further into the brain. Neuralink also has an R1 robot meant to implant the BCI system while avoiding vasculature.
A nine-minute livestream demonstration on Musk’s “X” social media platform (formerly known as Twitter) showed Noland Arbaugh using the Neuralink BCI to move a computer cursor and play chess online.
Arbaugh, a quadriplegic, said he was paralyzed below the shoulders in a diving accident eight years ago. His use of the Neuralink BCI to play chess marked the first public demonstration of the potential of the brain implant in humans.
Another hurdle for Neuralink?
The latest hurdle for Neuralink is far from the first. Earlier this year, questions arose around animal practices at the company. Additionally, some neuroscientists have frustrations about the lack of detailed information besides Musk’s social media posts.
Reuters reported about a year ago that the U.S. government would look into Neuralink after reports of errors resulting in repeated experiments, with more animals losing their lives as a result.
Now, following a letter from U.S. lawmakers urging the SEC to look into Neuralink’s monkey deaths (reported by Wired in November), Musk denied the allegations of gruesome deaths as a result of the BCI implant. Lawmakers also questioned the FDA’s inspection practices related to Neuralink earlier this year.
Business Insider reported that, at The New York Times Dealbook conference, Musk said the test monkeys live in “monkey paradise.” He went on to say that the implant set for first-in-human testing never directly caused a monkey’s death.
Neuralink was also reportedly fined for violating rules related to the movement of hazardous materials.
