Brain Implants Help 150+ People Speak and Move Again

Casey Harrell calls his brain implant "nothing short of revolutionary," and it's easy to see why. The climate activist, who has ALS and can't speak or move on his own, now talks to his daughter, connects with friends, and earns an income—all because of electrodes in his brain that decode his thoughts into speech.

For nearly three years, Harrell has used a brain-computer interface that translates his brain signals into words. He can surf the web, do his job, and live more independently than he ever thought possible after his diagnosis.

His device even includes a profanity filter so he can read to his daughter without accidentally swearing. The team at the University of California, Davis has continuously refined the technology, improving accuracy and adding features like privacy mode based on what Harrell needs in his daily life.

Harrell is part of a quiet revolution that's suddenly accelerating. Between 1998 and 2023, only 67 people worldwide had tried brain-computer interfaces in research studies. Since 2024 alone, that number has more than doubled to around 150 people.

The technology comes in different forms. Some devices, like Harrell's, plug into ports on the head. Others are fully wireless and implanted entirely inside the skull. Less invasive versions sit on the brain's surface or even work through electrode caps worn on the head.

Each approach involves trade-offs between signal quality and surgical risk, but all share the same goal: giving paralyzed people their independence back. Most users have spinal cord injuries that left them unable to move their arms and legs, and the devices help them control wheelchairs, computers, and other assistive technology.

China became the first country to approve a brain-computer interface for medical use this year. Companies like Neuralink have implanted 21 people in just two years, while Synchron, Neuracle, and Precision Neuroscience are all racing to expand their trials.

The Ripple Effect: Every volunteer who tests these devices helps researchers understand what works and what doesn't. When Harrell's team switched from cursor control to decoding speech, they opened new possibilities for people with ALS. His device now uses a voice clone based on recordings of his original voice, letting him sound like himself again.

Challenges remain. Scientists still don't fully understand why some devices that initially helped people with ALS eventually stopped working. The only way forward is through more research and brave volunteers willing to, as Harrell puts it, "pay it forward."

What started as experimental surgery for a few dozen people is becoming a real option for anyone facing paralysis. The future where thinking becomes doing is arriving faster than anyone expected.