Neuralink’s first human brain implant shows promise amid animal testing backlash

Neuralink’s first human brain implant delivered a visible milestone in January 2024, when the company implanted its device in Noland Arbaugh, a 29-year-old who was paralyzed below the shoulders after a diving accident. By March, Neuralink was showing Arbaugh using the implant to play chess and Civilization VI with his mind, a real demonstration that the company’s system could translate neural activity into action on a screen.

That progress marked a narrower achievement than Elon Musk once sold to the public. Musk had promoted Neuralink as a path to superhuman abilities and a merging of minds with AI, but the company’s early clinical work has instead tracked toward a more conventional medical goal: helping people with paralysis or speech disorders regain lost function. Neuralink received FDA clearance in May 2023 to begin its first-in-human study, called PRIME, and said it began recruiting that September. Its April 12, 2024 progress update said the participant’s neural signals were detected shortly after surgery and that he had used the end-to-end system for gaming and other applications.

The company’s human results arrived alongside a growing backlash over how Neuralink reached that point. Federal scrutiny had already begun in December 2022, when U.S. Department of Agriculture investigators were reported to be probing potential animal-welfare violations after internal complaints that testing was being rushed. In February 2024, FDA inspectors reportedly found quality-control and record-keeping problems in Neuralink’s California animal lab during a June 2023 inspection.

The animal record became a central part of the criticism because of the scale of the losses. Neuralink had killed about 1,500 animals since 2018, including more than 280 sheep, pigs and monkeys, according to the estimate that circulated in reporting on the company’s testing. That total was only approximate because Neuralink did not keep precise records. At least four experiments involving 86 pigs and two monkeys were marred by human errors, deepening questions about whether the pressure to move fast had come at the expense of basic lab discipline.

Neuralink’s first human success did not erase those concerns. It instead sharpened a larger policy question now facing the brain-computer-interface field: whether the real near-term value lies in restoring function for patients, or in the grander consumer-enhancement vision that Musk attached to the technology from the start. So far, the evidence points to the former, while the latter remains far beyond reach.