Science News

Article originally written by Shawn Wei ’26.

The history of brain-computer interfaces (BCI) dates back to 1929, when German psychiatrist Hans Berger discovered brain waves, giving rise to speculation that these waves could be used for communication and control. The expression brain-computer interface was first introduced by Jacques Vidal in his paper titled: “Toward Direct Brain-Computer Communications” in 1973. This marked the official beginning of BCI research. In the 21st century, BCI research has drawn increasing attention, and many research institutes and companies have begun to develop and innovate in this field, with Elon Musk’s Neuralink being one prominent example. Neuralink’s first product, Telepathy, is an implantable device that allows people to control their mobile phones or computers directly through their thoughts.

How does this work? Neuralink has designed extremely thin electrode wires, known as threads,  that can be surgically implanted into specific brain areas. These threads collect neural activity data, which are the electrical signals of neurons, and transmit it through a small device installed on the skull. These electrical signals are then decoded to understand the meaning of neuronal activity using machine learning algorithms and subsequently converted into commands controlling external devices like computer programs and prosthetic limbs.

Neuralink conducted its first human trial on January 28, 2024. The participant, Noland Arbaugh, is a 29-year-old man who had been paralyzed from the shoulders down for eight years after a diving accident. At the time, he could only tap on a tablet with a mouth-held stick. However, after receiving the implant, Arbaugh could move the cursor, surf the Internet, play games, and post messages simply by thinking.

Following this success, Neuralink launched a second human trial. The participant, Alex, was able to play the game Webgrid using only his mind within five minutes of implantation. On the same day, he broke mission records, achieving speed and accuracy beyond any other assistive technology and setting a new world record for brain-computer interface cursor control. While Noland initially played simpler games like chess and Mario Kart, Alex was able to play more complex games like CSGO. Before the implant, Alex used a mouth-operated device called QuadStick, which allowed only one joystick input, limiting simultaneous actions like moving and aiming. Now, thanks to the BCI implant, Alex can aim and move simultaneously, significantly improving his gaming experience and allowing him to perform complex actions such as packing, unpacking, and reloading.

In addition to gaming, Alex has used Neuralink to develop 3D designs with CAD software. Before his injury, Alex was an automotive technician, repairing various vehicles and large machinery. He had always wanted to use computer-aided design (CAD) software to design 3D objects, but the technical limitations of his assistive tools made it impossible. However, with the help of Neuralink, his dream has become a reality. Alex used Fusion 360 CAD software to create a custom mount for the Neuralink charger.

Despite these successes, technical challenges remain significant. Connecting the brain directly to a computer is extremely complex and delicate, and any small mistake has serious consequences. About 85% of the threads connected to Noland retracted a few weeks after the first patient’s surgery, resulting in decreased BCI performance. In response, Neuralink developed several solutions, including reducing the formation of air pockets in the skull during surgery and implanting the device deeper into brain tissue. Fortunately, Alex’s implant has not experienced any thread retraction. 

Looking forward, Neuralink plans to continue expanding the available controls to enhance participants’ experience with digital devices. They are working on decoding multiple clicks and simultaneous movement intents to provide full mouse and video game controller functionality. Additionally, they are developing algorithms to recognize handwriting intent for faster text entry. Musk made a bold statement: “If all goes well, there will be hundreds of people with Neuralinks within a few years, possibly tens of thousands in five years, and millions in ten years.”

Sources:

Can You Invest in Elon Musk’s Neuralink? (Updated 2024) (Cover Image)
https://investingnews.com/invest-neuralink-stock/

PRIME Study Progress Update — Second Participant
https://neuralink.com/blog/prime-study-progress-update-second-participant/

PRIME Study Progress Update — User Experience
https://neuralink.com/blog/prime-study-progress-update-user-experience/

Brain–computer interface
https://en.wikipedia.org/wiki/Brain%E2%80%93computer_interface

Neuralink — Pioneering Brain Computer Interfaces
https://neuralink.com/

Summary of over Fifty Years with Brain-Computer Interfaces—A Review – PMC
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7824107/