However, records obtained by PCRM and WIRED revealed that 12 previously healthy Rhesus macaques were euthanized by Neuralink due to problems with the company's implant. Health records offer no evidence that the 12 monkeys were terminally ill, as Musk claimed. Rhesus macaques commonly live around 20 years in captivity, with some reaching the age of 40. The average age of the 12 monkeys who died during Neuralink experiments was 7.25 years.
"It seems obvious to everyone but Elon Musk that Neuralink's device is unsafe and dangerous," PCRM research and advocacy director Ryan Merkley said in a statement. "Now he is deliberately misleading investors and the public by outright lying about the company's monkey experiments."
Veterinary records paint what WIRED called a "gruesome portrayal" of suffering endured by monkeys during Neuralink trials.
PCRM recounted the story of "Animal 15," a 6-year-old female Rhesus macaque assigned to Neuralink trials at the California National Primate Research Center (CNPRC) at the University of California, Davis in September 2017. The following spring, she began "task training," during which the animal is confined in a restraint device. She did not take well to the training and refused to eat. Then she and another monkey escaped from their cages.
On December 17, 2018, "Neuralink staff drilled holes into Animal 15's skull, removed part of her skull and skin to expose her brain, and implanted two electrodes, one in each hemisphere of her brain. The surgery lasted five hours."
According to research records, Animal 15 developed a host of medical problems, including excessive itching, bloody discharge, and loss of balance. She was repeatedly observed pulling on the port connector in her skull and was seen pressing her head against the floor, a possible sign of pain or neurological impairment.
On Christmas 2018, Animal 15 was seen "pulling and picking at the incision sites." Both of her eyes were swollen half-shut. By March, large quantities of discharge were observed coming from Animal 15's head; lab tests showed multiple bacterial infections on her implants. Her health declined until she was euthanized on March 21, 2019.
"A necropsy found that the Neuralink implants left parts of Animal 15's brain 'focally tattered,' that 'remnant electrode threads' were found in her brain, and there were indications of hemorrhaging," PCRM said.
In the case of "Animal 22," a monkey euthanized in March 2020, a necropsy report states that "the failure of this implant can be considered purely mechanical and not exacerbated by infection," an apparently direct contradiction of Musk's claim that no animals died from Neuralink implants.
A former Neuralink employee, who did not want to be named for fear of retaliation, told WIRED that Musk's claim is "ridiculous" and "straight fabrication."
A doctoral candidate currently researching at CNPRC—who also requested anonymity for similar reasons—told the outlet that "these are pretty young monkeys."
"It's hard to imagine these monkeys, who were not adults, were terminal for some reason," the researcher added.
As WIRED reported Wednesday:
If the SEC does investigate Musk's comments, it would mark at least the third federal probe linked to Neuralink's animal testing. In December 2022, Reuters reported that the U.S. Department of Agriculture's Office of Inspector General had launched a probe into Neuralink's treatment of some animal test subjects. In February 2023, the U.S. Department of Transportation opened an investigation into Neuralink over allegations of unsafe transport of antibiotic-resistant pathogens.
These investigations followed the U.S. Food and Drug Administration initially rejecting Neuralink's application, in early 2022, for approval to conduct in-human clinical trials. According to Reuters, the agency's major concerns involved the device's lithium battery, as well as the possibility that the implant's wires might migrate to other parts of the brain.
Despite this, the FDA in May gave Neuralink the green light to begin human trials. On Wednesday, the company announced it would start recruiting adults with quadriplegia due to vertical spinal cord injury or amyotrophic lateral sclerosis—ALS, or Lou Gehrig's disease—for trials.
Called the PRIME study, the trials will test Neuralink's ability to help people with paralysis control devices. The company said Wednesday that it aims to "grant people the ability to control a computer cursor or keyboard using their thoughts alone."
In 2018, the SEC charged Musk with securities fraud for a series of false and misleading posts on Twitter—which he later bought and rebranded as X—about potentially taking his electric car company Tesla private. In a settlement, Musk agreed to resign as Tesla's chairman and pay a $20 million penalty. The company was also hit with a $20 million fine.
