Brain-Computer Interface Trials Are Actually Taking Off Now

This week I read about Casey Harrell, a guy with ALS who researchers call “the first power user” of a brain implant. He’s been using a brain-computer interface (BCI) since July 2023, and it lets him speak, browse the web, and work as a climate activist mostly on his own. That’s three years of living with electrodes in his brain, connected to docking ports on his scalp that plug into a computer.

The UC Davis team behind his device has been iterating hard. They’ve dialed in accuracy, added a privacy mode, and even a “profanity filter” so he can talk to his daughter without accidentally dropping an F-bomb. Harrell himself calls it “nothing short of revolutionary”—it’s kept him employed, reconnected him with family, and let him read to his kid.

He’s one of a growing number of volunteers who, as he puts it, want to “pay it forward and do the scientific research” while getting some personal benefit. And that number is climbing fast.

Let me back up. BCIs aren’t all the same. Harrell’s setup is relatively invasive: electrodes embedded in his brain pick up speech-related electrical activity, connected to two ports on his head that plug into a computer. That computer runs software trained to decode his brain signals into phonemes—basic sound units—and predict what he wants to say. He uses an eye gaze tracker to correct errors before the speech plays out loud.

But there are less invasive options. Some BCIs are fully implanted and wireless, no plugging in. Others sit on the brain’s surface with wired electrodes, or even just a cap of electrodes on the scalp. The trade-off is brutal: the closer you get to the neurons, the better your signal, but the more invasive the surgery, the higher the complication risk.

Function varies too. Harrell has ALS, but most BCI users today have spinal cord injuries. They might be paralyzed from the neck down but can still speak and move their face. For them, BCIs control devices that help with mobility—like robotic arms or wheelchairs.

In 2024, researchers at the University of Houston published a roundup of all BCI trials from 1998 (when the first implant likely happened) through 2023. They found 21 research groups trialing BCIs in just 67 volunteers. That’s 25 years for 67 people.

Since then, the numbers have exploded. Mariska Vansteensel, a BCI researcher at University Medical Center Utrecht, told me it’s “increased a lot.” In January, Neuralink—Elon Musk’s BCI company—announced it had implanted 21 people in the past two years alone. That’s one-third of the historical total in a fraction of the time.

Synchron is running trials in North America and Australia. Shanghai-based Neuracle started a trial in November 2024 and recently got approval for use outside clinical trials. Precision Neuroscience, founded by a former Neuralink co-creator, is trialing a BCI that sits on the brain’s surface. Academic research hasn’t slowed either.

China became the first country to approve a BCI for medical use this year. That’s a big deal—regulatory approval opens the door for wider adoption, not just experimental setups.

So yeah, BCI research is properly taking off. The tech is improving, more people are volunteering, and the pipeline from trial to approval is shortening. But let’s not pretend it’s all smooth sailing. Invasive surgery still carries risks. The signal quality vs. invasiveness trade-off isn’t going away. And we’re still talking about dozens, not thousands, of users.

Still, for someone like Casey Harrell, it’s already life-changing. That’s not nothing.