Musk’s Neuralink to Start Human Trials of Brain Implant for Paralysis Patients

Trial will use a robot to surgically place a wireless brain-computer interface implant in a region of the brain that controls movement intention.

The Neuralink logo and Elon Musk are shown in an illustration from Dec. 19, 2022. Dado Ruvic/Illustration/Reuters

Elon Musk’s neurotechnology company Neuralink has received approval from an independent review board and hospital to begin recruiting for the first-ever human trials of its brain implant for paralysis patients.

In a statement, Neuralink announced that it has begun recruiting patients with quadriplegia because of a cervical spinal cord injury or amyotrophic lateral sclerosis (ALS) for the clinical trial.

The trial, known as the Precise Robotically Implanted Brain-Computer Interface study, or PRIME study, will use a robot to surgically place a wireless brain-computer interface (BCI) implant in a region of the brain that controls movement intention.

Once in place, the implant is “cosmetically invisible” and will “record and transmit brain signals wirelessly to an app that decodes movement intention,” the company stated.

San Francisco-based Neuralink, which was co-founded by Mr. Musk in 2016, aims to build “the first neural implant that will let you control a computer or mobile device anywhere you go,” according to its website.

The upcoming trial—expected to take roughly six years to complete—will test the safety and initial effectiveness of the implant, which will allow participants to control a computer cursor or keyboard using just their thoughts.

Neuralink’s study in humans is being conducted under the investigational device exemption (IDE) after it was granted approval from the Food and Drug Administration in May.

The company began testing brain implants in animals in 2019, and in 2020, it successfully implanted artificial intelligence microchips in the brain of a pig named Gertie.

Elon Musk, CEO of X, formerly known as Twitter, leaves a U.S. Senate bipartisan Artificial Intelligence (AI) Insight Forum at the U.S. Capitol in Washington on Sept. 13, 2023. Mandel Ngan/AFP via Getty Images

Concerns Over Animal Research

In April 2021, the startup published a video showing Pager, a 9-year-old macaque, playing computer games through a neural implant that was inserted into the monkey’s brain.

However, Neuralink’s animal research has also led to some concerns.

In February, the Department of Transportation announced that it was investigating the company over allegations of potential illegal movement of hazardous pathogens.

According to the department, Neuralink may have transported potentially dangerous pathogens when removing the chips from the monkeys’ brains without implementing proper measures to contain them. The implants may have carried infectious diseases in violation of federal law.

Separately, Reuters has reported that Neuralink is under investigation by the Department of Agriculture’s Office of Inspector General over potential violations of the Animal Welfare Act.

Mr. Musk has previously said that monkeys used by the company in animal trials enjoy doing the tasks and are happy, and that Neuralink “cares about animal welfare” amid concerns from animal rights groups.

According to a Neuralink brochure (pdf), the human trial will consist of a primary study, BCI research sessions, and a long-term follow-up. Participants will have nine at-home and in-person clinic visits for the first 18 months and will be asked to take part in the research sessions twice a week for one hour for the duration of the study. They will also need to complete 20 long-term follow-ups over five years.

Gert-Jan Oskam, 40, who was left paralyzed by a spinal cord injury, poses with his implants that allow him to walk naturally, during a news conference in Lausanne, Switzerland, on May 23, 2023. Fabrice Coffrini/AFP via Getty Images

Trial Eligibility

To be eligible for the study, participants must be at least 22 years old, have quadriplegia because of a spinal cord injury or ALS, and be at least one year post-injury “without improvement.”

They must also have a “consistent and reliable caregiver,” according to the company brochure.

Neuralink said on Sept. 19 that the study “represents an important step in our mission to create a generalized brain interface to restore autonomy to those with unmet medical needs.”

Mr. Musk’s startup is one of many that are testing implants to help people with paralysis.

In August, researchers at the University of California–San Francisco and the University of California–Berkeley revealed that a woman who was left severely paralyzed after suffering a stroke was able to communicate again thanks to a brain-computer interface that translates brain signals into modulated speech and facial expressions via AI.

Elsewhere, a paralyzed man was able to walk again for the first time in years thanks to an implant fitted in his brain and spinal cord by an international team of researchers led by Grégoire Courtine, professor Jocelyne Bloch, and others from the Swiss Federal Institute of Technology in Lausanne.

The implant has allowed the man to voluntarily move his legs and feet just by thinking about it.

Neuralink was valued at $5 billion in June.

Mimi Nguyen Ly and Reuters contributed to this report.