­By: Ugor Benedict

Early January this year, Neuralink, an American neurotechnological company owned by Elon Musk successfully implanted a brain chip in a 29-year-old volunteer patient, Noland Arbaugh. The event, which involved a surgical procedure of inserting a small chip in the brain, allowed Arbaugh, a quadriplegic paralyzed from shoulders down after a diving accident, to control a computer cursor with his brain.

Neuralink claimed that the surgery went extremely well and Arbaugh was able to go home the following day. It added that recovery was smooth after the surgery, and, a few weeks later, reported that Arbaugh could control a computer cursor with his brain, and even showcased him playing chess in a live video in March.

Fig. 1: Noland Arbaugh, the first human clinical trial for the Neuralink device. © The New York Times

What is this technology, and how does it work?

The Neuralink implant is a wireless, small, coin-sized, battery-powered, processing chip with fine threads that connect with the brain tissue to transmit brain signals. The major aim is to create a Brain-Computer Interface (BCI) that allows people with quadriplegia—paralysis of all four limbs—to control digital devices like computers, phones, gamepads, keyboards, and mouse cursors, with their thoughts alone.

The current version of the device called the ‘NI Implant’ is an intracortical BCI that records brain activity using 1,024 electrodes distributed across 64 fine threads, each of which is thinner than a human hair and can be independently placed in the brain.

Fig. 2: A disassembled view of the N1 Implant. © Neuralink Blog

The fine and flexible nature of the threads is designed to minimize risk and increase device functionality. Because these threads are impractical to manipulate by hand, a surgical robot was also built to efficiently insert them into the brain, so that the 1,024 electrodes can be correctly placed in the intracortical region of the brain.

Brain signals received by the electrodes are sent to electronics contained in the enclosure of the Implant, which processes and wirelessly transmits the signals to a Neuralink Application running on an external device, such as a computer or phone. The Application then decodes and translates the neural data into actions, such as the movement of a cursor on a computer screen.

The battery of the N1 Implant is inductively or wirelessly recharged by an N1 Charger, and this ability to both communicate and charge wirelessly makes it cosmetically invisible and usable without any physical connectors.

Fig. 3: High-level representation of how the N1 Implant, N1 Charger, Neuralink Application, and R1 Robot interact (objects in diagram not drawn to scale). © Neuralink Blog

How the PRIME Study led to the First-in-human Clinical Trial

The PRIME study, short for “Precise Robotically Implanted Brain-Computer Interface”, is an investigational medical device trial used by Neuralink to evaluate the safety and functionality of the Neuralink implant and surgical robot.

Neuralink began this study in 2017 with extensive research and experimentation with animals, such as sheep, pigs, and monkeys. Although the outcomes of animal testing yielded both success and failure for Neuralink, it was heavily criticized with accusations of animal abuse and animal rights violations. In April 2021, Neuralink demonstrated a monkey playing the game “Pong” using its brain implant.

The PRIME study began human trials after the company received the Food and Drug Agency (FDA) clearance for human clinical trials in May 2023 (FDA had initially rejected its proposals in 2022), and Neuralink started recruiting volunteer patients with quadriplegia. As a disclaimer, the company said that it does not guarantee any benefit for volunteers participating in the PRIME Study.

Noland Arbaugh then became Neuralink’s first human trial patient. But, while the surgery was a success and Arbaugh controlled a mouse cursor with his brain, there were later complications as 85% of the threads from the device completely detached and Arbaugh’s brain shifted about three times the amount of what the company expected.

In response to the complication, Neuralink made efforts to correct the error by modifying the algorithm to improve the conversion of signals to cursor movements and claimed that the changes made have improved Arbaugh’s performance with the device.

What will happen Next?

The world is eagerly watching out for what will happen to Noland Arbaugh, and the FDA is poised to take necessary actions from the outcome of the Neuralink’s human trial as to whether or not the trials should continue. Neuralink is, however, still recruiting volunteer patients and already planning its next human trial.

On the bright side, there is a glimmer of hope for advancement in medicine if the technology proves successful because quadriplegics will be able to control digital devices, thereby improving their health and well-being.

On the downside, MIT Technological Review, and many other groups, have accused Elon Musk and his Neuralink company of trying to stir up excitement rather than a genuine intent to solve health problems. Neuralink refused this accusation, reiterating that its major goal is to help quadriplegics live normal lives.

Of course, there is more to know about Neuralink but let’s part ways for now, after which I will be back to tell you about another new technology. The Neuralink Implant is indeed exciting and sparks curiosity; however, it is safe and cautious that we raise questions like: what are the ethical dilemmas involved? Will it eventually become a powerful exploitative tool used by scientists and the rich? Will merging humans and AI with it lead to a catastrophe? Will something strange happen that we yet know nothing about or even can imagine? All these and many more are troubling questions we need to answer.