Elon Musk’s successful bid of $44 billion to buy Twitter defied Wall Street pundits and social media wisdom. But it wasn’t brain surgery.

That will be much more difficult.

Viewed against the spotlight-basking Tesla or SpaceX, Musk’s private neurotech startup Neuralink, which aims to cut small holes in patients’ skulls and insert brain implants in them, often fades into the background. Yet it is the moonshot firm that has prompted some of the entrepreneur’s biggest boasts — and might yield some of his strongest head winds.

“I think he’s ultimately going to have a much harder time with Neuralink than he’ll have with all his other companies, including Twitter,” said Anna Wexler, a close observer of Neuralink and principal investigator of the University of Pennsylvania’s Wexler Lab, which focuses on emerging technology. “Medicine just has so many obstacles you don’t have in other areas, and it’s not clear he recognizes that.”

Neurotech is fraught enough that Meta bailed on its long-running investment in a mind-reading device last year, before its first implant.

Even as he was cranking the volume on his Twitter interest in April, Musk was touting the epic-ness of his “brain-machine interface,” or BMI — the tantalizing idea of a brain sending instructions directly to a computer. Musk said at Ted2022 that for much of the next decade, Neuralink will produce a medical wonder-tool that can cure paralysis and also “solve a very wide range of brain injuries including severe depression, morbid obesity, sleep, potentially schizophrenia — a lot of things that cause great stress to people.”

Scientists not only eye-roll such talk as standard Muskian hype but say that it deliberately ignores highly specific challenges not found in any of his other businesses. Wexler and others note that ethical and publicity pitfalls, the slow pace of trials, scientific uncertainty and even a 14-year-old competitor named Blackrock Neurotech could ensure it’s nearly a decade before any Neuralink product is mass-distributed, let alone effectively cures the ills Musk describes. They also look askance at the idea that a tech magnate who’s clashed with agencies such as the Securities and Exchange Commission is going to fit comfortably in the regulation-heavy business of medical treatments.


Yet the story is instructive not only for what it says about a freewheeling executive confronting a safeguard-heavy system but for what happens when a niche corner of science has a light thrown on it by a social media celebrity. All that wattage has created a divide within the neuro community. Is Musk a strange bedfellow they can live with to save people? Or a distraction whose hype will undermine critical research?

“The simple truth is, whether academics or entrepreneurs want to accept this, a lot of people would not be talking about neurotech had Elon not made this his focus,” said Marcus Gerhardt, chief executive and co-founder of the Utah-based Blackrock.

But, he added, the hype was also dangerous. “If you send a sporadic message, on the spur of the moment, to patients and get their hopes up, it’s irresponsible no matter how you try to turn it.”

BMI tech works by “recording” brain signals via electrodes implanted in the brain. That recording then allows an algorithm to combine all the signals and transmit them to a computer — potentially allowing paralyzed people to walk again via a robotic limb, or ALS patients who can’t speak to type instructions for a computer-generated voice.

While meaningful signals are generated by 100-200 electrodes (Blackrock’s amount, via the “Utah Array” approach), Neuralink captures 1,024 electrodes per implant, via a breakthrough “sewing” technique. Licensed from University of California, San Francisco, research, it involves the stitching together of many electrodes in a polymer thread. An implant is the diameter of a quarter, but five times thicker.

Neuralink was founded in 2016 but little publicized until a streaming event three years ago. Musk’s current boasts that he could make tetraplegics walk again are in fact a reining in of his promises then; at that presentation, he went far beyond medical uses to pledge that Neuralink’s devices could “achieve a sort of symbiosis with artificial intelligence” and “ultimately help secure humanity’s future as a civilization relative to AI.”


Musk has talked less about AI-melding recently (scientists say it is, at best, many decades away) but has kept the hype machine churning. “Short-term: solve brain/spine injuries. Long-term: human/AI symbiosis,” he tweeted in January 2021. In April 2021, Neuralink released a viral video that showed a monkey playing Pong with its mind. It set the internet ablaze with 6 million views and dozens of awed news articles.

Musk initially said he would start human trials by the end of 2020, then postponed to 2021. In January, he said he was hiring a director of those trials to begin this year; no such director has yet been announced.

And while 1,024 electrodes implanted in the brain instead of a couple hundred is an advance, neuroscientists say, it offers no demonstrable edge in human-mobility applications; Blackrock’s decade-old tech can basically do the same thing. That company already has FDA-approved devices implanted in 31 patients in trials around the world.

“It feels like there are two companies basically doing the same thing. One is doing it the right way and Elon Musk is doing it the wrong way,” said Laura Cabrera, an associate professor of engineering science and mechanics at Pennsylvania State University who follows neurotech companies.

Musk has undeniably propelled a wave of capital so far. Neuralink has raised at least $363 million in venture investment, including $100 million from Musk and an undisclosed sum from Google Ventures. Shortly after the MindPong video, Blackrock announced a $10 million venture round, its first, including an infusion from the venture-capital provocateur Peter Thiel. Two months later, Musk, Thiel’s PayPal co-founder, announced Thiel had also invested in Neuralink.

The Washington Post’s Jeremy B. Merrill contributed to this report.